Novel Cu(II)-based metal-organic framework STAM-1 as a sulfur host for Li-S batteries

Due to the increasing demand for energy storage devices, the development of high-energy density batteries is very necessary. Lithium-sulfur (Li-S) batteries have gained wide interest due to their particularly high-energy density. However, even this type of battery still needs to be improved. Novel Cu(II)-based metal-organic framework STAM-1 was synthesized and applied as a composite cathode material as a sulfur host in the lithium-sulfur battery with the aim of regulating the redox kinetics of sulfur cathodes. Prepared STAM-1 was characterized by infrared spectroscopy at ambient temperature and after in-situ heating, elemental analysis, X-ray photoelectron spectroscopy and textural properties by nitrogen and carbon dioxide adsorption at - 196 and 0 °C, respectively. Results of the SEM showed that crystals of STAM-1 created a flake-like structure, the surface was uniform and porous enough for electrolyte and sulfur infiltration. Subsequently, STAM-1 was used as a sulfur carrier in the cathode construction of a Li-S battery. The charge/discharge measurements of the novel S/STAM-1/Super P/PVDF cathode demonstrated the initial discharge capacity of 452 mAh g-1 at 0.5 C and after 100 cycles of 430 mAh g-1, with Coulombic efficiency of 97% during the whole cycling procedure at 0.5 C. It was confirmed that novel Cu-based STAM-1 flakes could accelerate the conversion of sulfur species in the cathode material.

Challenges with hippocampal MR spectroscopy as a surrogate for pre-radiotherapy assessment of neurocognitive impairment in patients with brain metastasis

AIM

Patients with multiple brain metastases (BM) benefit from hippocampal-avoiding whole brain radiotherapy (HA-WBRT), the challenging and less available form of WBRT. This study explores potential of pre-radiotherapy (pre-RT) hippocampal magnetic resonance spectroscopy (MRS) measuring hippocampal neuronal density as an imaging surrogate and predictive tool for assessing neurocognitive functions (NCF).

METHODS

43 BM patients underwent pre-RT hippocampal MRS. N-acetyl aspartate (NAA) concentration, a marker for neuronal density (weighted by creatine (Cr) and choline (Cho) concentrations), and neurocognitive function (NCF) tests (HVLT and BVMT) performed by certified psychologists were evaluated. Clinical variables and NAA concentrations were correlated with pre-RT NCFs.

RESULTS

HVLT and BVMT subtests showed pre-RT deterioration except for BVMT recognition. Significantly better NCFs were observed in women in HVLT subsets. Significantly higher NAA/Cr + Cho was measured in women (median 0.63 vs. 0.55; P=0.048) in the left hippocampus (no difference in the right hippocampus). In men, a positive correlation (0.51, P=0.018) between total brain volume and HVLT-TR, between left hippocampal NAA/Cr + Cho and HVLT-R (0.45, P=0.063), and between right hippocampal NAA/Cr + Cho and BVMT-recognition (0.49, P=0.054) was observed. In women, a borderline significant negative correlation was observed between left hippocampal NAA/Cr + Cho and BVMT-TR (-0.43, P=0.076) and between right NAA/Cr + Cho and HVLT-DR (-0.42, P=0.051).

CONCLUSION

Borderline statistically significant correlations were observed with speculative interpretation underlying the challenges of hippocampal MRS as a surrogate for neurocognitive impairment. Further studies need to be done to ascertain the opportunities for imaging predictors of benefit from memory sparing radiotherapy.

Toxicity of external beam accelerated partial-breast irradiation (APBI) in adjuvant therapy of early-stage breast cancer: prospective randomized study

BACKGROUND

Accelerated partial breast irradiation (APBI) is an alternative breast-conserving therapy approach where radiation is delivered in less time compared to whole breast irradiation (WBI), resulting in improved patient convenience, less toxicity, and cost savings. This prospective randomized study compares the external beam APBI with commonly used moderate hypofractionated WBI in terms of feasibility, safety, tolerance, and cosmetic effects.

METHODS

Early breast cancer patients after partial mastectomy were equally randomized into two arms- external APBI and moderate hypofractionated WBI. External beam technique using available technical innovations commonly used in targeted hypofractionated radiotherapy to minimize irradiated volumes was used (cone beam computed tomography navigation to clips in the tumor bed, deep inspiration breath hold technique, volumetric modulated arc therapy dose application, using flattening filter free beams and the six degrees of freedom robotic treatment couch). Cosmetics results and toxicity were evaluated using questionnaires, CTCAE criteria, and photo documentation.

RESULTS

The analysis of 84 patients with a median age of 64 years showed significantly fewer acute adverse events in the APBI arm regarding skin reactions, local and general symptoms during a median follow-up of 37 months (range 21-45 months). A significant difference in favor of the APBI arm in grade ≥ 2 late skin toxicity was observed (p = 0.026). Late toxicity in the breast area (deformation, edema, fibrosis, and pain), affecting the quality of life and cosmetic effect, occurred in 61% and 17% of patients in WBI and APBI arms, respectively. The cosmetic effect was more favorable in the APBI arm, especially 6 to 12 months after the radiotherapy.

CONCLUSION

External APBI demonstrated better feasibility and less toxicity than the standard regimen in the adjuvant setting for treating early breast cancer patients. The presented study confirmed the level of evidence for establishing the external APBI in daily clinical practice.

TRIAL REGISTRATION

NCT06007118.

Unilateral hippocampal sparing during whole brain radiotherapy for multiple brain metastases: narrative and critical review

Background

The landscape of brain metastases radiotherapy is evolving, with a shift away from whole-brain radiotherapy (WBRT) toward targeted stereotactic approaches aimed at preserving neurocognitive functions and maintaining overall quality of life. For patients with multiple metastases, especially in cases where targeted radiotherapy is no longer feasible due to widespread dissemination, the concept of hippocampal sparing radiotherapy (HA_WBRT) gains prominence.

Methods

In this narrative review we explore the role of the hippocampi in memory formation and the implications of their postradiotherapy lateral damage. We also consider the potential advantages of selectively sparing one hippocampus during whole-brain radiotherapy (WBRT). Additionally, by systematic evaluation of relevant papers published on PubMed database over last 20 years, we provide a comprehensive overview of the various changes that can occur in the left or right hippocampus as a consequence of radiotherapy.

Results

While it is important to note that various neurocognitive functions are interconnected throughout the brain, we can discern certain specialized roles of the hippocampi. The left hippocampus appears to play a predominant role in verbal memory, whereas the right hippocampus is associated more with visuospatial memory. Additionally, the anterior part of the hippocampus is more involved in episodic memory and emotional processing, while the posterior part is primarily responsible for spatial memory and pattern separation. Notably, a substantial body of evidence demonstrates a significant correlation between post-radiotherapy changes in the left hippocampus and subsequent cognitive decline in patients.

Conclusion

In the context of individualized palliative radiotherapy, sparing the unilateral (specifically, the left, which is dominant in most individuals) hippocampus could expand the repertoire of strategies available for adapted WBRT in cases involving multiple brain metastases where stereotactic radiotherapy is not a viable option. Prospective ongoing studies assessing various memory-sparing radiotherapy techniques will define new standard of radiotherapy care of patients with multiple brain metastases.

Hippocampal subfield volumetric changes after radiotherapy for brain metastases

Background

Changes in the hippocampus after brain metastases radiotherapy can significantly impact neurocognitive functions. Numerous studies document hippocampal atrophy correlating with the radiation dose. This study aims to elucidate volumetric changes in patients undergoing whole-brain radiotherapy (WBRT) or targeted stereotactic radiotherapy (SRT) and to explore volumetric changes in the individual subregions of the hippocampus.

Method

Ten patients indicated to WBRT and 18 to SRT underwent brain magnetic resonance before radiotherapy and after 4 months. A structural T1-weighted sequence was used for volumetric analysis, and the software FreeSurfer was employed as the tool for the volumetry evaluation of 19 individual hippocampal subregions.

Results

The volume of the whole hippocampus, segmented by the software, was larger than the volume outlined by the radiation oncologist. No significant differences in volume changes were observed in the right hippocampus. In the left hippocampus, the only subregion with a smaller volume after WBRT was the granular cells and molecular layers of the dentate gyrus (GC-ML-DG) region (median change -5 mm3, median volume 137 vs. 135 mm3; P = .027), the region of the presumed location of neuronal progenitors.

Conclusions

Our study enriches the theory that the loss of neural stem cells is involved in cognitive decline after radiotherapy, contributes to the understanding of cognitive impairment, and advocates for the need for SRT whenever possible to preserve cognitive functions in patients undergoing brain radiotherapy.

Dosimetric patterns of failure in the era of novel chemoradiotherapy in newly-diagnosed glioblastoma patients

BACKGROUND

Patterns of failure (POF) may provide an alternative quantitative endpoint to overall survival for evaluation of novel chemoradiotherapy regimens with glioblastoma.

MATERIALS AND METHODS

POF of 109 newly-diagnosed glioblastoma patients per 2016 WHO classification who received conformal radiotherapy with concomitant and adjuvant temozolomide were reviewed. Seventy-five of those patients also received an investigational chemotherapy agent (everolimus, erlotinib, or vorinostat). Recurrence volumes were defined with MRI contrast enhancement. POF at protocol (POFp), initial (POFi), and RANO (POFRANO) progression timepoints were characterized by the percentage of recurrence volume within the 95% dose region. POFp, POFi, and POFRANO of each patient were categorized (central, non-central, or both).

RESULTS

POF of the temozolomide-only control cohort were unchanged (79% central, 12% non-central, and 9% both) across protocol, initial, and RANO progression timepoints. Unlike the temozolomide-only cohort, POF of the collective novel chemotherapy cohort appeared increasingly non-central when comparing POFi with POFp, with a non-central component increasing from 16% to 29% (p = 0.078). POF did not correlate with overall survival or time to progression.

CONCLUSION

POF of patients receiving a novel chemotherapy appeared to be influenced by the timepoint of analysis and were increasingly non-central at protocol progression as compared with initial recurrence, suggesting that recurrence originates from the central region. Addition of everolimus and vorinostat appeared to influence POF, despite similar survival outcomes with the temozolomide-only control group. In studies dealing with novel therapeutic agents, robust and properly-timed dosimetric POF analysis may be helpful to evaluate biologic aspects of novel agents.

Effects of Reoperation Timing on Survival among Recurrent Glioblastoma Patients: A Retrospective Multicentric Descriptive Study

Glioblastoma inevitably recurs, but no standard regimen has been established for treating this recurrent disease. Several reports claim that reoperative surgery can improve survival, but the effects of reoperation timing on survival have rarely been investigated. We, therefore, evaluated the relationship between reoperation timing and survival in recurrent GBM. A consecutive cohort of unselected patients (real-world data) from three neuro-oncology cancer centers was analyzed (a total of 109 patients). All patients underwent initial maximal safe resection followed by treatment according to the Stupp protocol. Those meeting the following criteria during progression were indicated for reoperation and were further analyzed in this study: (1) The tumor volume increased by >20-30% or a tumor was rediscovered after radiological disappearance; (2) The patient's clinical status was satisfactory (KS ≥ 70% and PS WHO ≤ gr. 2); (3) The tumor was localized without multifocality; (4) The minimum expected tumor volume reduction was above 80%. A univariate Cox regression analysis of postsurgical survival (PSS) revealed a statistically significant effect of reoperation on PSS from a threshold of 16 months after the first surgery. Cox regression models that stratified the Karnofsky score with age adjustment confirmed a statistically significant improvement in PSS for time-to-progression (TTP) thresholds of 22 and 24 months. The patient groups exhibiting the first recurrence at 22 and 24 months had better survival rates than those exhibiting earlier recurrences. For the 22-month group, the HR was 0.5 with a 95% CI of (0.27, 0.96) and a p-value of 0.036. For the 24-month group, the HR was 0.5 with a 95% CI of (0.25, 0.96) and a p-value of 0.039. Patients with the longest survival were also the best candidates for repeated surgery. Later recurrence of glioblastoma was associated with higher survival rates after reoperation.

Eighteen years' experience with tumor treating fields in the treatment of newly diagnosed glioblastoma

Introduction

The prognosis of glioblastoma remains unfavorable. TTFields utilize low intensity electric fields (frequency 150-300 kHz) that disrupt cellular processes critical for cancer cell viability and tumor progression. TTFields are delivered via transducer arrays placed on the patients' scalp. Methods: Between the years 2004 and 2022, 55 patients (20 female), aged 21.9-77.8 years (mean age 47.3±11.8 years; median 47.6 years) were treated with TTFields for newly-diagnosed GBM, and compared to 54 control patients (20 females), aged 27.0-76.7 years (mean age 51.4±12.2 years; median 51.7 years) (p=0.08). All patients underwent gross total or partial resection of GBM. One patient had biopsy only. When available, MGMT promoter methylation status and IDH mutation was detected.

Results

Patients on TTFields therapy demonstrated improvements in PFS and OS relative to controls (hazard ratio: 0.64, p=0.031; and 0.61, p=0.028 respectively). TTFields average time on therapy was 74.8% (median 82%): median PFS of these patients was 19.75 months. Seven patients with TTFields usage ≤60% (23-60%, mean 46.3%, median 53%) had a median PFS of 7.95 months (p=0.0356). Control patients with no TTFields exposure had a median PFS of 12.45 months. Median OS of TTF patients was 31.67 months compared to 24.80 months for controls.

Discussion

This is the most extensive study on newly-diagnosed GBM patients treated with TTFields, covering a period of 18 years at a single center and presenting not only data from clinical trials but also a group of 36 patients treated with TTFields as a part of routine clinical practice.

Case report: radiation-induced lumbosacral plexopathy - a very late complication of radiotherapy for cervical cancer

BACKGROUND

Lumbosacral plexopathy caused by radiotherapy is a rare but severe consequence of cancer treatment. This condition often leads to varying degrees of sensory and motor impairment. Neurological complications, which are typically permanent, manifest a long period after irradiation.

CASE PRESENTATION

We describe a case of progressive lower extremity weakness and sensory impairment in a woman who had been effectively treated with radiotherapy for cervical cancer with development 36 years after irradiation. The electrophysiological assessment revealed a subacute bilateral axonal lesion of the lumbosacral plexus. None of the clinical manifestations, serology, cerebrospinal fluid or imaging data discovered an explanation other than radiation-induced lumbosacral plexopathy (RILP).

CONCLUSIONS

This case demonstrates that RILP may emerge more than 30 years after the radiotherapy.

SURG-08. COMBINED LOCAL TREATMENT OF BRAIN METASTASES: SURGERY AND POSTOPERATIVE STEREOTACTIC RADIOTHERAPY

INTRODUCTION

Modern comprehensive local treatment of BM provides the possibility of adequate local control while maintaining a satisfactory quality of life.

METHODS

Patients after metastasectomy and postoperative radiotherapy treated between 2007-2020 were evaluated. Local control was assessed separately at the site of the operated MM (localPFS) and separately in other parts of the brain (distalPFS).

RESULTS

A total of 118 patients were enrolled (70 with WBRT), 54% were women, the median age was 60 years, the median performance status Karnofsky 80%. The most common primary tumor was lung carcinoma (39/118, 33%). Targeted stereotactic radiotherapy was significantly more often indicated in operations performed after 2016 (p < 0.001). In the period 2013-2019, gross total resection was achieved significantly more often (83 vs 64%; p = 0.061). The median follow-up is 49 months. The median overall survival (OS) is 9 months (6.2 - 12), the median localPFS 22 months (14 - unattainable), median distPFS 11 months (6.8 - 27 months), median extracranialPFS 11 months (5.9 - 15). Stratification of patients according to the prognostic index brainmetgpa.com led to significant separation of patients for OS (p = 0.00017). In a multivariate analysis, stereotactic radiotherapy was statistically significant positive prognostic factor for OS compared to WBRT (median OS 17 vs. 5.6 months, HR 0.59, p = 0.018) with no effect on localPFS.

CONCLUSION

Our results of comprehensive local treatment of BM are comparable with the results presented by important foreign studies from prestigious oncology centers. We described targeted stereotactic postoperative radiotherapy as an independent positive prognostic factor after brain metastasectomy. The study was supported by the programme project of the Ministry of Health of the Czech Republic with reg. no. NV18-03-00398, NV19-03-00501 and NV19-03-00559 and Supported by Ministry of Health, Czech Republic-conceptual development of research organization (FNBr, 65269705).

PATH-02. ANALYSIS OF MICRORNA EXPRESSION IN BRAIN METASTASES USING NEXT-GENERATION SEQUENCING

BACKGROUND

Brain metastases (BMs) are intracranial tumors that frequently occur in adult cancer patients. Because the prognosis of patients with BM individually varies, it would be useful to improve prognostic scoring tools by including new high-performance biomarkers. MicroRNAs (miRNAs) appear to be promising in this regard as they are highly stable and, thus, suitable for both next-generation sequencing (RNA-Seq) and retrospective analyses in formalin-fixed and paraffin-embedded (FFPE) tissues.Material and

METHODS

Total RNA enriched for miRNAs was isolated from 71 freshly frozen histopathologically confirmed BMs with origin in 5 tumor types (ca lung - 37%, melanoma - 23%, ca breast - 18%, RCC - 15%, CRC - 7%) using mirVana miRNA Isolation Kit (Thermo Fisher Scientific). Sequencing libraries were prepared from RNA using the QIAseq miRNA Library Kit (Qiagen) and sequenced using the NextSeq 500 platform (Illumina). The miRNA molecules were subsequently transcribed from total RNA samples isolated from a retrospective set of 119 FFPE tissues using the TaqMan Advanced miRNA cDNA Synthesis Kit, and the expression of selected miRNAs was validated in a pilot experiment by qPCR using TaqMan Fast Advanced Master Mix and appropriate TaqMan MicroRNA Assays (all from Thermo Fisher Scientific).

RESULTS

The differential analysis identified 373 miRNAs with significantly different expression among the 5 BMs groups (p< 0.001). A molecular classifier based on the expression of 32 miRNAs was able to classify all samples correctly. Out of these, seven, including miR-122-5p, miR-141-3p, miR-146a-5p, miR-194-5p, miR-200c-3p, miR-211-3p, and miR-215-5p, were chosen for subsequent validation and their significantly different expression in 5 BMs groups was validated.

CONCLUSIONS

Presented results confirm the importance of studying dysregulated miRNA expression in BM and the diagnostic potential of validated miRNAs. The study was prepared with the grant support of the Ministry of Health of the Czech Republic - grant No. NV18-03-00398.

CNSC-13. TUMOR INFILTRATION OF GAMMA-DELTA T CELLS IN GLIOBLASTOMA

Gamma-delta (γδ) T cells are innate immunity effector lymphocytes with known prominent anti-tumor reactivity against aggressive glioblastoma (GBM). However, therapeutic approaches have had limited success due to the protective blood-brain-barrier and the immunosuppressive GBM tumor microenvironment. In this study, we determined Vδ1 a Vδ2 γδ T cell populations in peripheral blood and paired tumor tissue samples in patients (n=40) following the resection and throughtout the therapy follow-up. Tumor samples were processed using enzymatic kits and gentleMACSTM Dissociator (Miltenyi Biotec Inc.) and tumor-infiltrating γδ T lymphocytes (TILs) were analyzed by flow cytometry.We found infiltration of both intratumoral CD3+ γδ T cell subsets in 68% tumor samples. We detected Vδ1 γδ T cells in the range 0-0.8% (median 0.26%). Majority of GBM patients presented the Vδ2 subset among TILs in the range 0-13.8% (median 1.5%). Functional studies showed prominent cytotoxicity of magnetically sorted Vδ1 a Vδ2 γδ T cells against GBM cell lines and more importantly against primary tumors. Detailed phenotypic profiling and single-cell sequencing of Vδ2 γδ T cells is currently underway. Next, we identified the EphA2 receptor as one of the targets for tumor-reactive Vδ1 γδ T cells. Specifically, we found that blocking of EphA2 expression resulted in significant inhibition of GBM killing mediated by Vδ1 γδ T cells. Furthermore, Luminex xMAP technology identified significantly elevated levels of stress ligand MICA and check-point inhibitor ligands PD-L1 (B7-H1, CD274) and B7-H3 (CD276) and galectin-9 in patients‘ plasma samples at diagnosis compared to age-matched controls.The patient’s clinical course and therapeutic protocols will be discussed.This study was supported by Ministry of Health, Czech Republic (grant NV19-05-00410 to AK) by Ministry of Health, Czech Republic-conceptual development of research organization (FNBr, 65269705). All rights reserved.

Human Papillomavirus-Related Non-Metastatic Oropharyngeal Carcinoma: Current Local Treatment Options and Future Perspectives

Over the last two decades, human papillomavirus (HPV) has caused a new pandemic of cancer in many urban areas across the world. The new entity, HPV-associated oropharyngeal squamous cell carcinoma (OPSCC), has been at the center of scientific attention ever since, not only due to its distinct biological behavior, but also because of its significantly better prognosis than observed in its HPV-negative counterpart. The very good treatment outcomes of the disease after primary therapy (minimally-invasive surgery, radiation therapy with or without chemotherapy) resulted in the creation of a separate staging system, reflecting this excellent prognosis. A substantial proportion of newly diagnosed HPV-driven OPSCC is diagnosed in stage I or II, where long-term survival is observed worldwide. Deintensification of the primary therapeutic methods, aiming at a reduction of long-term toxicity in survivors, has emerged, and the quality of life of the patient after treatment has become a key-point in many clinical trials. Current treatment recommendations for the treatment of HPV-driven OPSCC do not differ significantly from HPV-negative OPSCC; however, the results of randomized trials are eagerly awaited and deemed necessary, in order to include deintensification into standard clinical practice.

P17.14.B Strategy of the recurrent Glioblastoma treatment. Three neuro-oncology centers study

Background

The prognosis for patients with Glioblastoma (GBM) remains dismal. The most aggressive multimodal therapy (maximally radical and safe tumor resection, followed by the Stupp protocol oncotherapy) has yielded the best treatment outcomes. Notwithstanding the slowly prolonged patient′s overall survival, this tumor inevitable recurs. An optimal therapy of the recurrent GBM is still a controversial theme.The aim of our study is to evaluate our treatment strategy of recurrent GBM.

Material and Methods

For this study, we retrospectively selected a group of resected recurrent GBM patients in a period from June 1, 2009 to December 31, 2019, which were treated in tree Czech neuro-oncologic centers. All patients underwent early post-surgical MRI (within 72 h) to determine resection radicality. Following resection, patients received periodic checkups with MRI every 3 months until death. Patients with psedoprogession were excluded. Information about all surgeries, oncotherapies, patient clinical condition, MRI, PET/CT, and results of histological, immunohistochemical, molecular genetic, and cytogenetic investigations was gathered.We consider surgery for recurrent GBM in case, if:

1.The tumor volume increasing > 20-30% or tumor rediscovery after radiologic disappearing.

2.Clinic condition - Karnofsky score (KS) ≥ 70% and Performance status (PS) WHO ≤ gr. 2.

3.Localized tumor, without multilfocality.

4.Assumed the least tumor volume reduction > 80%.

Results

We gathered 122 patients with recurrent GBM, 98,9% of tumors was determined as wild-type, age median was 53,36 years. All patients underwent Stupp protocol oncotherapy after prime surgery. Median of OS from prime surgery was 21 months (15.8, 29.6). The best results proved a surgery of GBM recurrency proceeding more than 6 months after diagnosis. OS2 (from redo up to the death) was 7.4 months (6.41, 11.3). 43.3% of patients recalled temozolomide chemotherapy. We confirmed positive link between OS and resection radicality, negative relations between OS and a postoperative neurologic deficits. Only limited relation was presented between OS and repeated oncotherapy. Relation to the further histologic, imunohistochemic, cytogenetic and molecular markers will be discussed.

Conclusion

Due to the common unfavorable outcomes of GBM therapy, out of despair, we often decided for repeated surgery. The aim of our study was avoid ineffective surgical overtreatment. The best results of surgery yield right selected recurrent GBMs. Surgery of GBM regrown during initial oncotherapy (6 months after prime surgery) presented unsatisfactory effects. Positive effect of the surgical radicality and clinic status were confirmed. Again, necessity of second-line oncotherapy has been emerged. Supported by Ministry of Health of the Czech Republic, grant nr. NV19- 04-00281 and grant nr. NU21-03-00195

P11.57.B Combined surgery and radiotherapy for brain metastases. Retrospective analysis of a consecutive cohort of 118 patients

Background

Despite current advances in systemic therapy for brain metastases, neurosurgery remains the preferred method of choice in patients with limited brain metastases. Postoperative radiotherapy indicated to reduce the risk of local recurrence is recommended in all patients after surgery. The aim of this retrospective study is to describe clinical characteristics and survival outcomes in consecutive cohorts of patients treated by this combined local treatment.

Material and Methods

Clinical data were retrieved from electronic medical records for consecutive patients who underwent surgery for brain metastases between 2007 and 2019. All patients underwent postsurgery radiotherapy. Local progression free survival (localPFS) evaluated the local control at the operated site. DistalPFS at the other parts of the brain. Univariable and multivariable analysis of survival characteristics was performed. The Median follow-up was 49 months.

Results

A total of 118 patients were included (54% women, median age 60 years, median Karnofsky index 80% at the time of radiotherapy). Single metastasis was treated in 66%, while 11% presented with more than 3 metastases. The most common primary diagnosis was lung cancer (33%) and breast (20%). Radical surgery was achieved in 92/117 (79 % of patients). In total, only 48/118 (41%) of patients underwent targeted radiotherapy (mostly fractionated stereotactic radiotherapy of 25Gy in 5 fractions). Significantly more patients (p<0.001) underwent targeted radiotherapy during 2016-2019 (45/48) compared to 2007-2015 period (3/48). A total of 20% of those who underwent postsurgery whole brain radiotherapy (WBRT) had a special technic of hippocampal sparing WBRT of WBRT with simultaneous integrated boost to remaining brain metastases. Median overall survival (OS) for all patients was 9 months (6.2 - 12), median localPFS 22 months (14 - not reached), median distalPFS 11 months (6.8 - 27) and median extracranialPFS 11 months (5.9 - 15). A significant (p=0.00017) difference in OS was while grouping patients according to Graded prognostic assessment (brainmetgpa.com). Significantly better OS was in the cohort of patients with targeted stereotactic radiotherapy (17months) vs. WBRT (5.6 months; p=0.00069) with no difference in local PFS, distal PFS or extracranialPFS. Multivariable analysis revealed type or radiotherapy, control of primary tumor, number of brain metastases 1-2 and the possibility to discontinue corticosteroids to be independent variables for OS.

Conclusion

Targeted fractionated stereotactic radiotherapy to tumor bed after metastasectomy was associated with improved survival compared to postsurgery WBRT in our cohort. Stereotactic radiotherapy should be preferred in all workplaces with adequate radiotherapy technology. Supported by Ministry of Health of the Czech Republic AZV, NV18-03-00469 and NV18-03-00398.

FMISO-Based Adaptive Radiotherapy in Head and Neck Cancer

Concurrent chemoradiotherapy represents one of the most used strategies in the curative treatment of patients with head and neck (HNC) cancer. Locoregional failure is the predominant recurrence pattern. Tumor hypoxia belongs to the main cause of treatment failure. Positron emission tomography (PET) using hypoxia radiotracers has been studied extensively and has proven its feasibility and reproducibility to detect tumor hypoxia. A number of studies confirmed that the uptake of FMISO in the recurrent region is significantly higher than that in the non-recurrent region. The escalation of dose to hypoxic tumors may improve outcomes. The technical feasibility of optimizing radiotherapeutic plans has been well documented. To define the hypoxic tumour volume, there are two main approaches: dose painting by contour (DPBC) or by number (DPBN) based on PET images. Despite amazing technological advances, precision in target coverage, and surrounding tissue sparring, radiation oncology is still not considered a targeted treatment if the “one dose fits all” approach is used. Using FMISO and other hypoxia tracers may be an important step for individualizing radiation treatment and together with future radiomic principles and a possible genome-based adjusting dose, will move radiation oncology into the precise and personalized era.

The Significance of MicroRNAs in the Molecular Pathology of Brain Metastases

Brain metastases are the most frequent intracranial tumors in adults and the cause of death in almost one-fourth of cases. The incidence of brain metastases is steadily increasing. The main reason for this increase could be the introduction of new and more efficient therapeutic strategies that lead to longer survival but, at the same time, cause a higher risk of brain parenchyma infiltration. In addition, the advances in imaging methodology, which provide earlier identification of brain metastases, may also be a reason for the higher recorded number of patients with these tumors. Metastasis is a complex biological process that is still largely unexplored, influenced by many factors and involving many molecules. A deeper understanding of the process will allow the discovery of more effective diagnostic and therapeutic approaches that could improve the quality and length of patient survival. Recent studies have shown that microRNAs (miRNAs) are essential molecules that are involved in specific steps of the metastatic cascade. MiRNAs are endogenously expressed small non-coding RNAs that act as post-transcriptional regulators of gene expression and thus regulate most cellular processes. The dysregulation of these molecules has been implicated in many cancers, including brain metastases. Therefore, miRNAs represent promising diagnostic molecules and therapeutic targets in brain metastases. This review summarizes the current knowledge on the importance of miRNAs in brain metastasis, focusing on their involvement in the metastatic cascade and their potential clinical implications.

Abstract 908: Small RNA-seq analysis of PIWI-interacting RNAs in glioblastoma stem cells: Identification of new therapeutic targets in glioblastoma patients

Introduction: Glioblastoma (GBM) is the most common malignancy affecting the CNS. Despite radical therapy, recurrence of GBM is a frequent and relatively early event in the course of the disease. One of the putative mechanisms of early recurrence of GBM is the existence of glioblastoma stem cells (GSCs) that can resist therapy and subsequently establish new GBM foci. PIWI-interacting RNAs (piRNAs), responsible for maintaining genome stability, may play a key role not only in the biology of germ and stem cells but also GSCs since their dysregulated expression has been described in several cancers, including GBM. Thus, the identification of specific piRNAs in GSCs could allow the distinction of these cells from other GBM cells and their eventual targeting. Some piRNAs could also be promising biomarkers useful for prognosis and prediction of disease progression.

Material and Methods: Native GBM tissues dissociated using the Papain Dissociation System were used for culturing of paired cell primary cultures. Cells were divided into two aliquots with different culture conditions. GSCs were cultured in DMEM/F12 medium supplemented with bFGF and EGF growth factors. DMEM medium containing 10% fetal bovine serum (FBS) was used to culture non-stem GBM cells. Subsequently, the presence of neural stem cell markers CD133 and SOX2, the ability of GSCs to establish tumors in immunodeficient mice, and the ability to differentiate into more mature cell types were analyzed. RNA isolated from the paired primary cultures was used for small-RNA sequencing (RNA-seq). QIAseq miRNA Library Kit was used for the preparation of cDNA libraries. Sequencing analysis was performed using the NextSeq 500/550 High Output v2 Kit (75 cycles) and the NextSeq 500 sequencer.

Results: Twelve paired primary cultures were prepared to global piRNA expression profiling. Small RNA-seq bioinformatics analysis identified between 3.45 and 5.51% of unique mapped piRNA reads in all samples; GSCs expressing higher levels of piRNA molecules in comparison with paired GBM cells. Subsequently, we identified a set of significantly differentially expressed piRNAs in GSCs. Expression of selected piRNAs was then artificially regulated in primary GSCs in vitro, and the effect of these molecules on neurosphere formation, viability, and cell genome stability was analyzed. Finally, we also observed an association of piR-23231 with overall survival of GBM patients. All results will be presented at the AACR Annual Meeting 2022.

Conclusion: Based on the results so far, piRNAs seem to play an important role in GSCs as well as GBM biology and their targeting may be a promising tool for therapy of GBM patients. The study was supported by the programme project of the Ministry of Health of the Czech Republic with reg. no. NV19-03-00501 and NV19-03-00559.

Citation Format: Jiri Sana, Frantisek Siegl, Marek Vecera, Pavel Fadrus, Jaroslav Juracek, Petra Pokorna, Karolina Trachtova, Tomas Kazda, Ondrej Slaby. Small RNA-seq analysis of PIWI-interacting RNAs in glioblastoma stem cells: Identification of new therapeutic targets in glioblastoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 908.

HLA-E and HLA-F Are Overexpressed in Glioblastoma and HLA-E Increased After Exposure to Ionizing Radiation

BACKGROUND/AIM

Glioblastoma (GBM) is one of the deadliest human cancers responding very poorly to therapy. Although the central nervous system has been traditionally considered an immunologically privileged site with an enhanced immune response, GBM appears to benefit from this immunosuppressive milieu. Immunomodulatory molecules play an important role in immune tumor-host interactions. Non-classical human leukocyte antigens (HLA) class Ib molecules HLA-E, HLA-F, and HLA-G have been previously described to be involved in protecting semi-allogeneic fetal allografts from the maternal immune response and in transplant tolerance as well as tumoral immune escape. Unfortunately, their role in GBM remains poorly understood. Our study, therefore, aimed to characterize the relationship between the expression of these molecules in GBM on the transcriptional level and clinicopathological and molecular features of GBM as well as the effect of ionizing radiation.

MATERIALS AND METHODS

We performed the analysis of HLA-E, HLA-F, and HLA-G mRNA expression in 69 GBM tissue samples and 21 non-tumor brain tissue samples (controls) by reverse transcription polymerase chain reaction. Furthermore, two primary GBM cell cultures had been irradiated to identify the effect of ionizing radiation on the expression of non-classical HLA molecules.

RESULTS

Analyses revealed that both HLA-E and HLA-F are significantly up-regulated in GBM samples. Subsequent survival analysis showed a significant association between low expression of HLA-E and shorter survival of GBM patients. The dysregulated expression of both molecules was also observed between patients with methylated and unmethylated O-6-methylguanine-DNA methyltransferase (MGMT) promoter. Finally, we showed that ionizing radiation increased HLA-E expression level in GBM cells in vitro.

CONCLUSION

HLA-E and HLA-F play an important role in GBM biology and could be used as diagnostic biomarkers, and in the case of HLA-E also as a prognostic biomarker.

PATH-01. SMALL RNASEQ ANALYSIS OF MICRORNAS IN BRAIN METASTASIS

MicroRNAs (miRNAs) are a well-known subclass of short non-coding RNAs responsible for posttranscriptional gene silencing and have been described as dysregulated in many cancers. They have also been shown to be both specific diagnostic, prognostic, and predictive biomarkers as well as therapeutic targets. Therefore, specific miRNA expression patterns of BMs of various origins could serve as a promising diagnostic tool for determining both the original tumor and the prognosis in patients with BMs of unknown origin. For identifying significantly dysregulated miRNAs among BMs (n=90) with various origin and non-tumor brain tissues (n=12), small RNAseq analyses were used. cDNA libraries were prepared using QIAseq miRNA Library Kit and purified by Qiaseq beads. The final sequencing analyses were performed by Next 500/550 High Output v2 Kit-75 cycles using the NextSeq 500 instrument. For miRNA mapping and analysis, Miraligner and MirBase were used. Bioinformatic analysis of obtained sequencing data identified 472 significantly dysregulated miRNAs (logFc >2, adj.p-value< 0.05) between BM and non-tumor samples. The comparison of BMs origin from lung BMs (n = 26) with other BMs revealed 132 significantly dysregulated miRNAs, mainly miR-4662a-5p, miR-1179, miR-211-5p, miR-146a-5p, and miR-194-5p. The most significantly dysregulated miRNAs in breast BMs were miR-4728-3p, miR-211-5p, miR-184, miR-365b-5p, and miR-2115-3p. In BMs originating from melanoma, miR-200c-3p, miR-141-5p, miR-200b-5p, miR-514a-3p, and miR-200b-3p showed the most aberrant expression. We have demonstrated that miRNA profiling could be a potent tool for the partition of brain metastases based on their origin. We found that miRNA signatures corresponding to particular origins are rather distinct from the profiles of the rest of BMs. Our results suggest that after validation, miRNA profiling can be used to identify the origin of brain metastases and potentially for the refinement of the diagnosis. Supported by the Ministry of Health of the Czech Republic, grant nr. NV18-03-00398.

P14.59 Rapid early progression of glioblastoma is not related to cortical/neural stem cells regions

BACKGROUND

Rapid early progression (REP) of glioblastoma after surgery observed on pre-radiotherapy MRI scan is common. Subventricular zone (SVZ) and hippocampal regions are supposed to harbor astrocyte-like neural stem cells (NSC) with tumors arising from these transformed stem cells threatening of higher risk of REP. REP is defined as a new enhancing tumor or >25% increase in enhancement before radiotherapy. Lim′s classification of initial glioblastoma location related to these NSC regions predicts invasive and multifocal tumor phenotype. Glioblastomas are classified preoperatively into four groups by the spatial relationship of the contrast-enhancing lesion with the SVZ and cortex. The aim of this retrospective single-institutional study is to evaluate the relations of this Lim classification on REP in unselected cohort of glioblastoma patients.

MATERIAL AND METHODS

Patients receiving radiotherapy between 2014–2017 were analyzed, 95 were evaluable. 47 patients (30.5%) were treated with the Stupp regimen. Lim1 classification (contact with cortex as well as SVZ) was presented in 74(48%) patients, Lim2 (contact with SVZ only) in 22(14.3%), Lim3 (contact with cortex only) in 50(32.5%) and Lim4 in 8(5.2%) patients. A total of 52% of patients developed REP.

RESULTS

Significantly better overall survival was with Stupp regimen (23.3 vs. 8.6 months, p<0.001) and without REP (18.5 vs. 10.2 months, p=0.001). There was no significant impact of time to start of radiotherapy. No significant relation between REP and Lim classification was observed.

CONCLUSION

The initial location is not predictive for REP. Patients experiencing REP have significantly worse overall survival and modification of their management represents an urgent unmet clinical need. Molecular and clinical biomarkers indicating an increased risk of REP are needed.Presented will also be an already published analysis of clinical factors associated with REP in glioblastoma and the effect of REP and treatment on survival outcomes. Newly, we will introduce the investigator-initiated prospective academic clinical trial (GlioMET) focused on optimization of glioblastoma radiotherapy by 11C-Methionine PET scan in patients with REP. Supported by Ministry of Health of the Czech Republic AZV, No.18-03-00469 and AZV NU20-03-00148.

Small RNA Sequencing Identifies PIWI-Interacting RNAs Deregulated in Glioblastoma-piR-9491 and piR-12488 Reduce Tumor Cell Colonies In Vitro

Glioblastoma (GBM) is the most frequently occurring primary malignant brain tumor of astrocytic origin. To change poor prognosis, it is necessary to deeply understand the molecular mechanisms of gliomagenesis and identify new potential biomarkers and therapeutic targets. PIWI-interacting RNAs (piRNAs) help in maintaining genome stability, and their deregulation has already been observed in many tumors. Recent studies suggest that these molecules could also play an important role in the glioma biology. To determine GBM-associated piRNAs, we performed small RNA sequencing analysis in the discovery set of 19 GBM and 11 non-tumor brain samples followed by TaqMan qRT-PCR analyses in the independent set of 77 GBM and 23 non-tumor patients. Obtained data were subsequently bioinformatically analyzed. Small RNA sequencing revealed 58 significantly deregulated piRNA molecules in GBM samples in comparison with non-tumor brain tissues. Deregulation of piR-1849, piR-9491, piR-12487, and piR-12488 was successfully confirmed in the independent groups of patients and controls (all p < 0.0001), and piR-9491 and piR-12488 reduced GBM cells’ ability to form colonies in vitro. In addition, piR-23231 was significantly associated with the overall survival of the GBM patients treated with Stupp regimen (p = 0.007). Our results suggest that piRNAs could be a novel promising diagnostic and prognostic biomarker in GBM potentially playing important roles in gliomagenesis.

BSCI-01. Small RNAseq analysis of microRNAs in brain metastasis

MicroRNAs (miRNAs) are a well-known subclass of short non-coding RNAs responsible for posttranscriptional gene silencing and have been described as dysregulated in many cancers. They have also been shown to be both specific diagnostic, prognostic, and predictive biomarkers as well as therapeutic targets. Therefore, specific miRNA expression patterns of BMs of various origins could serve as a promising diagnostic tool for determining both the original tumor and the prognosis in patients with BMs of unknown origin.

For identifying significantly dysregulated miRNAs among BMs (n = 90) with various origin and non-tumor brain tissues (n = 12), small RNAseq analyses were used. cDNA libraries were prepared using QIAseq miRNA Library Kit and purified by Qiaseq beads. The final sequencing analyses were performed by Next 500/550 High Output v2 Kit-75 cycles using the NextSeq 500 instrument. For miRNA mapping and analysis, Miraligner and MirBase were used.

Bioinformatic analysis of obtained sequencing data identified 472 significantly dysregulated miRNAs (logFc>2, adj.p-value<0.05) between BM and non-tumor samples. The comparison of BMs origin from lung BMs (n = 26) with other BMs revealed 132 significantly dysregulated miRNAs, mainly miR-4662a-5p, miR-1179, miR-211-5p, miR-146a-5p, and miR-194-5p. The most significantly dysregulated miRNAs in breast BMs were miR-4728-3p, miR-211-5p, miR-184, miR-365b-5p, and miR-2115-3p. In BMs originating from melanoma, miR-200c-3p, miR-141-5p, miR-200b-5p, miR-514a-3p, and miR-200b-3p showed the most aberrant expression.

We have demonstrated that miRNA profiling could be a potent tool for the partition of brain metastases based on their origin. We found that miRNA signatures corresponding to particular origins are rather distinct from the profiles of the rest of BMs. Our results suggest that after validation, miRNA profiling can be used to identify the origin of brain metastases and potentially for the refinement of the diagnosis.

Supported by the Ministry of Health of the Czech Republic, grant nr. NV18-03-00398.

Drug interaction profile of TKI alectinib allows effective and safe treatment of ALK+ lung cancer in the kidney transplant recipient

ALK targeting with tyrosine kinase inhibitors (TKIs) is a highly potent treatment option for the therapy of ALK positive non-small cell lung cancer (NSCLC). However, pharmacokinetics of TKIs leads to clinically significant drug interactions, and the interfering co-medication may hamper the anti-cancer therapeutic management. Here, we present for the first time a drug interaction profile of ALK-TKIs, crizotinib and alectinib, and immunosuppressive agent cyclosporine A in kidney transplant recipients diagnosed with ALK+ lung cancer. Based on therapeutic drug monitoring of cyclosporin A plasma level, the dose of cyclosporine A has been adjusted to achieve a safe and effective therapeutic level in terms of both cancer treatment and kidney transplant condition. Particularly, 15 years upon the kidney transplantation, the stage IV lung cancer patient was treated with the 1st-line chemotherapy, the 2nd-line ALK-TKI crizotinib followed by ALK-TKI alectinib. The successful therapy with ALK-TKIs has been continuing for more than 36 months, including the period when the patient was treated for COVID-19 bilateral pneumonia. Hence, the therapy of ALK+ NSCLC with ALK-TKIs in organ transplant recipients treated with cyclosporine A may be feasible and effective.

Integrated dia-gnostics of diffuse gliomas

Recently, the World Health Organization (WHO) classification of tumours of the central nervous system (CNS) has brought essential changes. The currently valid revised WHO 2016 classification of CNS tumours introduced the concept of integrated dia-gnostics, which incorporated not only histopathological morphological finding and immunophenotype but also molecular-genetic characteristics of the tumour. Thus, the final integrated dia-gnosis comprises the traditional morphological and growth pattern characteristics of a tumour including histopathological grade and also specific molecular bio-markers. The classification of tumour based on a combination of both tumour phenotype and genotype enables more precise prognostic stratification, increases the objectivity of dia-gnostics and prediction of response to treatment. In 2017, an international platform, The Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy - not official WHO (cIMPACT-NOW), was established to create and formulate practical recommendations for integrated dia-gnostics of CNS tumours and upcoming WHO classification. The incorporation of molecular bio-markers into the integrated dia-gnostics radically changed the classification of diffuse gliomas, which include entities with different morphological characteristics, genetic alterations and bio-logical behaviour. This review article summarizes essential morphological, immunophenotypical and molecular genetic characteristics of diffuse gliomas within the scope of integrated dia-gnostics according to the valid WHO classification of tumours of the CNS and subsequent recommendations of dia-gnostic approaches. This work was supported by grant of the Ministry of Health of the Czech Republic - Conceptual Development of a Research Organization (MMCI 00209805) and Grant Agency of Masaryk University (MUNI/A/1562/2018). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.

The use of cisplatin in patients after kidney transplantation with chronic renal insufficiency: Is the benefit higher than potential risks in therapy of non-seminomatous germ cell tumors?

RATIONALE

The use of cisplatin in patients with chronic kidney disease (CKD) is risky and depends on a number of factors. The optimal procedure in stage I of a non seminomatous germ cell tumor without proven lymphangioinvasion after orchiectomy is controversial and is the subject of a number of discussions due to the lack of randomized studies assessing individual treatment options. The adjuvant method of choice is surveillance or application of cisplatin-based chemotherapy with the risk of treatment related nephrotoxicity. Information about cisplatin safety in renal transplant patients is particularly limited. The aim of this paper is to share the experience with the application of adjuvant chemotherapy Bleomycin, Etoposide, Cisplatin (BEP) in high-risk patient with nonseminoma after kidney transplantation.

PATIENT CONCERNS

We report a case report of rare group of high-risk patient with non-seminomatous germ cell testicular tumor (NSGCT) after kidney transplantation before application of adjuvant chemotherapy BEP. Patient presented with month-long discomfort in the scrotal area. Previously, he was treated with chronic kidney disease based on chronic glomerulonephritis, which was treated with repeated kidney transplantation.

DIAGNOSIS

The ultrasound examination for a month-long discomfort in the scrotal area found a solid mass of the left testis. Radical inguinal orchiectomy confirmed NSGCT with the presence of lymphovascular invasion (LVI). Postoperative staging with computed tomography of the chest and abdomen did not show obvious dissemination of the disease.

INTERVENTIONS

Reducing original dose of chemotherapeutics according to the recommendations of the summary of product characteristics led to only a transient increase in creatinine levels.

OUTCOMES

The 5-year risk of relapse in surveillance was reduced to around 3% by applying cisplatin-based chemotherapy.

LESSONS

Application of cisplatin-based chemotherapy is safe and effective in patients with CKD and in patients with a kidney transplant.

Radical external beam reirradiation of recurrent head and neck cancer

BACKGROUND

Recurrent head and neck carcinomas represent a therapeutic challenge for the surgeons as well as for the treating radiation oncologists. Despite advances in the treatment of newly dia-gnosed head and neck carcinomas, relapses occur very frequently and contribute significantly to patient mortality. External beam reirradiation is still considered to be a controversial therapeutic intervention. Historically, in the era of 2- and 3-dimensional conformal radiotherapy, its narrow therapeutic ratio has long led to a general concern that the potential benefit could not sufficiently outweigh the high risk associated with the treatment. The unfavorable therapeutic ratio, however, could be positively influenced by the use of modern techniques of intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), stereotactic body radiation therapy (SBRT) and heavy-ion radiotherapy (protons, carbon ions).

PURPOSE

The purpose of this review is to create a practical tool for clinical decision-making on the type of patient suitable for reirradiation and the exact type of radiotherapy technique with respect to its expected therapeutic effect, toxicity profile and availability throughout the institutions. In the introductory section, selection of patients is defined with an emphasis on factors that significantly affect overall survival and may be particularly useful in shared decision-making approach within multidisciplinary teams. Furthermore, the text deals with the individual types of external beam radiotherapy techniques (IMRT, SBRT, heavy-ion radiotherapy) with a clear summary of therapeutic outcomes and toxicity from published scientific evidence that had a significant impact on clinical practice.

Penis as a primary site of an extraskeletal Ewing sarcoma: A case report

RATIONALE

The Ewing sarcoma family of malignant tumors is a group of tumors characterized by morphologically similar round-cell neoplasms and by the presence of a common chromosomal translocation; Ewing sarcoma family of tumors typically occur in children and young adults between 4 to 15 years of age. The primary tumor usually originates in the bone, extraskeletal localization is rare.

PATIENT CONCERN

We present a case report concerning a 32-year-old male patient with a primary involvement of the penis.

DIAGNOSIS

The histopathology from the first penile biopsy showed a small-cell neuroendocrine carcinoma; however, that result was based on a sample obtained at a different facility than the Sarcoma Center, where the investigating pathologist did not have the adequate expertise. The patient then underwent a radical penectomy and a second reading of the histology was demanded after a radical penile amputation when Ewing sarcoma with R1 resection was confirmed.

INTERVENTIONS

The patient was referred to the national Sarcoma Center, where - using a multidisciplinary approach - the treatment was started with curative intent. However, it was preceded by a non-standard initiation of the therapy due to the poor primary diagnosis.

OUTCOMES

The non-standard therapy at the onset of the disease caused a poor prognosis of an otherwise curable diagnosis. Despite all that, the patient survived for a relatively long time.

LESSONS

The treatment of sarcomas with atypical localizations should be conducted by an experienced multidisciplinary team in a center with experience in sarcoma treatment.

Effect of Acupuncture in Pain Management of Head and Neck Cancer Radiotherapy: Prospective Randomized Unicentric Study

This prospective randomized open-label trial aimed to evaluate the role of acupuncture in the treatment of pain related to curative and adjuvant (chemo)radiotherapy of head and neck cancer. Patients in two arms (30 patients in each arm) underwent standard oncology therapy and standard supportive care with or without acupuncture. The stratification factors were the type of treatment and chemotherapy indication. The toxicity assessed was represented by pain rated on a 10-point pain scale and analgesic use. Average pain (AP) and the worst pain during the day (WP) were significantly lower in the acupuncture arm during radiotherapy (AP median 0.16 vs. 1.36, p < 0.001; WP median 0.90 vs. 1.96, p < 0.001) and three months after radiotherapy (AP median 0.07 vs. 0.50, p < 0.001; WP median 0.30 vs. 0.83, p = 0.002). The analgesic consumption between arms was statistically significantly different. A median of the proportion of days when the patients used analgesics was 8% and 32.5% during radiotherapy (p = 0.047) and 0% and 20.8% during three months after radiotherapy (p = 0.006) for the acupuncture and control arm, respectively. Results point out lower analgesic consumption and milder pain in acupuncture arm. Acupuncture consequently offers another alternative to standard treatment leading to a reduction in the toxicity of oncological treatment.

Stereotactic Body Radiotherapy for Lymph Node Oligometastases: Real-World Evidence From 90 Consecutive Patients

AIMS

To evaluate the efficacy and toxicity of extracranial stereotactic body radiotherapy (SBRT) in the treatment of oligometastatic lymph node involvement in the mediastinum, retroperitoneum, or pelvis, in a consecutive group of patients from real clinical practice outside clinical trials.

METHODS

A retrospective analysis of 90 patients with a maximum of four oligometastases and various primary tumors (the most common being colorectal cancers). The endpoints were local control of treated metastases (LC), freedom from widespread dissemination (FFWD), progression-free survival (PFS), overall survival (OS), and freedom from systemic treatment (FFST). Acute and delayed toxicities were also evaluated.

RESULTS

The median follow-up after SBRT was 34.9 months. The LC rate at three and five years was 68.4 and 56.3%, respectively. The observed median FFWD was 14.6 months, with a five-year FFWD rate of 33.7%. The median PFS was 9.4 months; the three-year PFS rate was 19.8%. The median FFST was 14.0 months; the five-year FFST rate was 23.5%. The OS rate at three and five years was 61.8 and 39.3%, respectively. Median OS was 53.1 months. The initial dissemination significantly shortened the time to relapse, death, or activation of systemic treatment-LC (HR 4.8, p < 0.001), FFWD (HR 2.8, p = 0.001), PFS (HR 2.1, p = 0.011), FFST (HR 2.4, p = 0.005), OS (HR 2.2, p = 0.034). Patients classified as having radioresistant tumors noticed significantly higher risk in terms of LC (HR 13.8, p = 0.010), FFWD (HR 3.1, p = 0.006), PFS (HR 3.5, p < 0.001), FFST (HR 3.2, p = 0.003). The multivariable analysis detected statistically significantly worse survival outcomes for initially disseminated patients as well as separately in groups divided according to radiosensitivity. No grade III or IV toxicity was reported.

CONCLUSION

Our study shows that targeted SBRT is a very effective and low toxic treatment for oligometastatic lymph node involvement. It can delay the indication of cytotoxic chemotherapy and thus improve and maintain patient quality of life. The aim of further studies should focus on identifying patients who benefit most from SBRT, as well as the correct timing and dosage of SBRT in treatment strategy.

Second primary malignancies in colorectal cancer patients

The prevalence of second primary malignancies (SPMs) in the western world is continually increasing with the risk of a new primary cancer in patients with previously diagnosed carcinoma at about 20%. The aim of this retrospective analysis is to identify SPMs in colorectal cancer patients in a single-institution cohort, describe the most frequent SPMs in colorectal cancer patients, and discover the time period to occurrence of second primary tumors. We identified 1174 patients diagnosed with colorectal cancer in the period 2003–2013, with follow-up till 31.12.2018, and median follow-up of 10.1 years, (median age 63 years, 724 men). A second primary neoplasm was diagnosed in 234 patients (19.9%). Older age patients, those with early-stage disease and those with no relapse have a higher risk of secondary cancer development. The median time from cancer diagnosis to development of CRC was 8.9 years for breast cancer and 3.4 years for prostate cancer. For the most common cancer diagnosis after primary CRC, the median time to development was 0–5.2 years, depending on the type of malignancy. Patients with a diagnosis of breast, prostate, or kidney cancer, or melanoma should be regularly screened for CRC. CRC patients should also be screened for additional CRC as well as cancers of the breast, prostate, kidney, and bladder. The screening of cancer patients for the most frequent malignancies along with systematic patient education in this field should be the standard of surveillance for colorectal cancer patients.

The Impact of Diabetes Mellitus on the Second Primary Malignancies in Colorectal Cancer Patients

Introduction

All colorectal cancer (CRC) survivors have an increased risk of developing second primary malignancies (SPMs). The association between diabetes mellitus (DM) and the risk of cancer is well known. However, the role of DM and its therapy in the development of SPMs in CRC patients is not well described.

Methods

In this single-institutional retrospective analysis we identified 1,174 colorectal carcinoma patients, median follow-up 10.1 years, (median age 63 years, 724 men). All patients over 18 years with histologically confirmed CRC who were admitted in the period 1.1. 2003- 31.12.2013 and followed-up till 31.12. 2018 at the Masaryk Memorial Cancer Institute (MMCI) were screened for eligibility. The exclusion criteria were CRC diagnosed at autopsy, lost to follow-up and high risk of development of SPMs due to hereditary cancer syndrome. Tumours are considered multiple primary malignancies if arising in different sites and/or are of a different histology or morphology group. Comparisons of the basic characteristics between the patients with SPM and the patients without SPM were performed as well as comparison of the occurrence of SPMs by the site of diagnosis between the DM and non-DM cohorts and survival analyses.

Results

A SPM was diagnosed in 234 (20%) patients, DM in 183 (15%) patients. DM was diagnosed in 22.6% of those with SPM vs. in 13.8% of those without SPM (p=0.001). The most common types of SPMs in DM patients were other CRC, kidney, lung, bladder and nonmelanoma skin cancer, but only carcinoma of the liver and bile duct tracts was significantly more common than in the group without DM. Although breast cancer was the second most common in the group with DM, its incidence was lower than in the group without DM, as well as prostate cancer. A significantly higher incidence of SPMs was found in older CRC patients (≥ 65 years) and in those with lower stage colon cancer and DM. No significant difference in DM treatment between those with and without a SPM was observed including analysis of type of insulin.

Conclusion

CRC patients with diabetes mellitus, especially those with older age, and early stages of colon cancer, should be screened for second primary malignancies more often than the standard population. Patients without DM have longer survival. According to the occurrence of the most common second malignancies, a clinical examination, blood count, and ultrasound of the abdomen is appropriate, together with standard breast and colorectal cancer screening, and lung cancer screening under certain conditions, and should be recommended in CRC survivors especially in patients with intercurrent DM, however the necessary frequency of screening remains unclear.

Recurrent Nasopharyngeal Cancer: Critical Review of Local Treatment Options Including Recommendations during the COVID-19 Pandemic

Simple Summary

Options for the curative treatment of locally recurrent nasopharyngeal carcinoma include surgery or re-irradiation. Both approaches have been scientifically explored, yet there is no consensus on the indication or definitive preference of the above two salvage treatments. The aim of this review is to summarize the current evidence on the local treatment of recurrent nasopharyngeal carcinoma. The feasibility, safety, and efficacy of salvage surgery and radical re-irradiation are discussed. Recommendations on treatment modifications during the coronavirus disease 2019 pandemic are included as well.

Abstract

Recurrent nasopharyngeal carcinoma represents an extremely challenging therapeutic situation. Given the vulnerability of the already pretreated neurological structures surrounding the nasopharynx, any potential salvage retreatment option bears a significant risk of severe complications that result in high treatment-related morbidity, quality of life deterioration, and even mortality. Yet, with careful patient selection, long-term survival may be achieved after local retreatment in a subgroup of patients with local or regional relapse of nasopharyngeal cancer. Early detection of the recurrence represents the key to therapeutic success, and in the case of early stage disease, several curative treatment options can be offered to the patient, albeit with minimal support in prospective clinical data. In this article, an up-to-date review of published evidence on modern surgical and radiation therapy treatment options is summarized, including currently recommended treatment modifications of both therapeutic approaches during the coronavirus disease 2019 pandemic.

Management of Immune-Related Endocrinopathies in Anticancer Treatment with Checkpoint Inhibitors

Modern immunotherapy with checkpoint inhibitors has become the backbone treatment for many cancers. However, it is often accompanied by immune-related side effects, which may differ depending on the nature of the treatment. The frequency of adverse reactions increases with the number of patients receiving immunotherapy. The situation has become even more difficult with the advent of combination immunotherapy. Although the kinetics of the onset and duration of toxicity have been well described, caution should be exercised. In clinical practice, cases with atypical courses often occur. Ignorance of the problem can lead to underestimation of symptoms and damage to the patient. Immune-related side effects are variable and any organ can be affected. In addition to skin, intestinal and liver toxicity, immune-related endocrinopathy is another relatively frequent toxicity. Thyroid, pituitary and adrenal glands are most commonly affected. Symptoms of endocrinopathy are often nonspecific, which may complicate a differential diagnosis. Fortunately, most toxicities are grade 1 and 2; however, in routine clinical practice, care must be exercised to detect the onset of life-threatening toxicity such as an adrenal crisis or type 1 diabetes mellitus with ketoacidosis. It is unclear whether high doses of corticosteroids are effective in preserving endocrine gland function. Long-term hormone replacement therapy is essential because immune-related endocrinopathy is often irreversible, unlike other immune-related toxicities. Close cooperation with an endocrinologist is therefore very important. This work was supported by MH CZ - DRO (MMCI, 00209805). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.

Everolimus-related unilateral abdominal lymphedema in a renal cancer patient: A case report

RATIONALE

Unilateral manifestation of lymphedema during everolimus therapy has been described only rarely, mostly in transplant recipients.

PATIENT CONCERNS

We report the first case of a patient who developed unilateral abdominal lymphedema, during a short period of everolimus treatment for renal cancer.

DIAGNOSIS

The abdominal asymmetry occurred only on the right side of the abdomen, neither ultrasound nor CT scan detected ascites but showed enlargement of the abdominal wall. The Naranjo Adverse Drug Reaction Probability scale was evaluated, in this case, a score of 6 indicated a probable adverse reaction to everolimus.

INTERVENTIONS

Discontinuation of everolimus therapy led to immediate alleviation and reduction of the lymphedema, with worsening once again after initiating retreatment with everolimus at a reduced dose.

OUTCOMES

The patient's lymphedema recovered after discontinuation of everolimus.

LESSONS

This rare case demonstrates the importance of the selection of mammalian target of rapamycin inhibitors using caution, especially for patients with a high risk of developing lymphedema.

Radical external beam re-irradiation in the treatment of recurrent head and neck cancer: Critical review

Management of patients with recurrent head and neck cancer remains a challenge for the surgeon as well as the treating radiation oncologist. Even in the era of modern radiotherapy, the rate of severe toxicity remains high with unsatisfactory treatment results. Intensity-modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), and heavy-ion irradiation have all emerged as highly conformal and precise techniques that offer many radiobiological advantages in various clinical situations. Although re-irradiation is now widespread in clinical practice, little is known about the differences in treatment response and toxicity using diverse re-irradiation techniques. In this review, we provide a comprehensive overview of the role of radiation therapy in recurrent or second primary head and neck cancer including patient selection, therapeutic outcome, and risk using different re-irradiation techniques. Critical review of published evidence on IMRT, SBRT, and heavy-ion full-dose re-irradiation is presented including data on locoregional control, overall survival, and toxicity.

Real-World Evidence in Glioblastoma: Stupp's Regimen After a Decade

The aim of this retrospective study is to provide real-world evidence in glioblastoma treatment and to compare overall survival after Stupp's regimen treatment today and a decade ago. A current consecutive cohort of histologically confirmed glioblastoma irradiated from 1/2014 to 12/2017 in our cancer center was compared with an already published historical control of patients treated in 1/2003-12/2009. A total of new 155 patients was analyzed, median age 60.9 years, 61% men, 58 patients (37%) underwent gross total tumor resection. Stupp's regimen was indicated in 90 patients (58%), 65 patients (42%) underwent radiotherapy alone. Median progression-free survival in Stupp's regimen cohort was 6.7 months, median OS 16.0 months, and 2-year OS 30.7%. OS was longer if patients were able to finish at least three cycles of adjuvant chemotherapy (median 23.3 months and 43.9% of patients lived at 2 years after surgery). Rapid early progression prior to radiotherapy was a negative prognostic factor with HR 1.87 (p = 0.007). The interval between surgery and the start of radiotherapy (median 6.7 weeks) was not prognostically significant (p = 0.825). The median OS in the current cohort was about 2 months longer than in the historical control group treated 10 years ago (16 vs. 13.8 months) using the same Stupp's regimen. Taking into account differences in patient's characteristics between current and historical cohorts, age, extent of resection, and ECOG patient performance status adjusted HR (Stupp's regimen vs. RT alone) for OS was determined as 0.45 (p = 0.002).

The tumor immune microenvironment and its implications for clinical outcome in patients with oropharyngeal squamous cell carcinoma

BACKGROUND

We examined PD-L1 expression on tumor cells (TCs) and immune cells (ICs) and density of CD3⁺ and CD8⁺ tumor-infiltrating lymphocytes (TILs) in patients with oropharyngeal squamous cell carcinoma (OPSCC) and investigated their significance on clinicopathological characteristics and clinical outcomes.

METHODS

In a cohort of 65 patients treated by definitive intensity-modulated radiotherapy (IMRT) with curative intent, immunohistochemical analysis of PD-L1 expression on TCs and ICs, and TIL subtyping was performed on primary biopsy tumor tissues, followed by prognostic evaluation of these immune response-related parameters including classification into four tumor immune microenvironment (TIM) types. To evaluate HPV status, p16 immunohistochemistry was performed.

RESULTS

Densities of CD3⁺ and CD8⁺ TILs and PD-L1 expressions on TCs and ICs were significantly higher in p16+/HPV-mediated OPSCC. Patients with high densities of stromal CD8⁺ TILs displayed significantly better overall survival (OS) and progression-free survival (PFS). PD-L1 expression neither on tumor cells nor on immune cells affected survival outcomes. Distribution of TIM types based on the combination of PD-L1 expression on TCs and densities of CD8⁺ TILs is significantly different in p16+ compared with p16- OPSCC. In type III TIM (TC-PD-L1+/low CD8⁺ TIL density), significantly better OS was shown in p16+ group compared with p16- OPSCC.

CONCLUSION

The prognostic and predictive role of tumor immune microenvironment was confirmed for patients with OPSCC. Combining HPV status with the evaluation of densities of CD8⁺ TILs and PD-L1 expression including TIM classification might be of high clinical interest and warrants further prospective evaluation.

Acupuncture in the treatment of acute toxicity during and after head and neck cancer radiotherapy: Interim analysis of randomized prospective open-label trial

AIMS

The aim of this investigator-initiated prospective randomized open-label single institutional trial is to evaluate the role of acupuncture in the treatment of acute skin and mucosal toxicity, xerostomia, and perception of taste, pain, and nausea related to curative and adjuvant (chemo)radiotherapy of head and neck cancer. This paper reports pilot data of the first 30 enrolled patients.

METHODS

Patients were randomized to undergo standard of care radiotherapy ± chemotherapy and support care defined by our institutional standard operating procedures alone or in the combination with acupuncture which was initiated with the first signs of any toxicity.

RESULTS

Fifteen patients were enrolled in both arms and all finished the treatment as planned.The median pain was significantly lower in the acupuncture arm (median 1.6 points vs. 2.5 points on a 10-item Likert scale; P=0.035) as well as duration of acute pain (median 31 days vs. 54 days; P=0.031). Patients with acupuncture had significantly shorter duration of acute skin (median 44 days vs. 109 days; P<0.001) and mucosal toxicity (median 34 days vs. 109 days; P<0.001) with no difference in grading of toxicity (median grade 1.6 vs. 1.5; P=0.701 and median grade 1.4 vs. 1.6; P=0.204 for skin and mucosa, respectively). No significant difference was found for other toxicity domains, with the exception of salivation toxicity which was significantly lower in acupuncture arm (median grade 1.3 vs. 1.7; P=0.048).

CONCLUSION

In this interim analysis, acupuncture leads to lower pain andfaster disappearance of skin and mucosal toxicity after (chemo)radiotherapy of head and neck cancer. Description and validation of acupuncture using scientific approaches will further enhance acceptance of this method by both patients and health care providers.

TRIAL REGISTRATION

Clinicaltrials.gov - NCT03751566.

Prospective evaluation of contrast-enhanced ultrasound of breast BI-RADS 3-5 lesions

BACKGROUND

To determine the benefit of contrast-enhanced ultrasound (CEUS) in the assessment of breast lesions.

METHODS

A standardized contrast-enhanced ultrasound was performed in 230 breast lesions classified as BI-RADS category 3 to 5. All lesions were subjected to qualitative and quantitative analysis. MVI (MicroVascular Imaging) technique was used to derive qualitative analysis parameters; blood perfusion of the lesions was assessed (perfusion homogeneity, type of vascularization, enhancement degree). Quantitative analysis was conducted to estimate perfusion changes in the lesions within drawn regions of interest (ROI); parameters TTP (time to peak), PI (peak intensity), WIS (wash in slope), AUC (area under curve) were obtained from time intensity (TI) curves. Acquired data were statistically analyzed to assess the ability of each parameter to differentiate between malignant and benign lesions. The combination of parameters was also evaluated for the possibility of increasing the overall diagnostic accuracy. Biological nature of the lesions was verified by a pathologist. Benign lesions without histopathological verification (BI-RADS 3) were followed up for at least 24 months.

RESULTS

Out of 230 lesions, 146 (64%) were benign, 67 (29%) were malignant, 17 (7%) lesions were eliminated. Malignant tumors showed statistically significantly lower TTP parameters (sensitivity 77.6%, specificity 52.7%) and higher WIS values (sensitivity 74.6%, specificity 66.4%) than benign tumors. Enhancement degree also proved to be statistically well discriminating as 55.2% of malignant lesions had a rich vascularity (sensitivity 89.6% and specificity 48.6%). The combination of quantitative analysis parameters (TTP, WIS) with enhancement degree did not result in higher accuracy in distinguishing between malignant and benign breast lesions.

CONCLUSIONS

We have demonstrated that contrast-enhanced breast ultrasound has the potential to distinguish between malignant and benign lesions. In particular, this method could help to differentiate lesions BI-RADS category 3 and 4 and thus reduce the number of core-cut biopsies performed in benign lesions. Qualitative analysis, despite its subjective element, appeared to be more beneficial. A combination of quantitative and qualitative analysis did not increase the predictive capability of CEUS.

Targeted Radiotherapy of the Tumor Cavity after Surgical Resection of Aggressive Recurrent Brain Metastasis: A Case Report

Postoperative management of patients with brain metastases is controversial. Besides local control, cognitive function and quality of life are the most important outcomes of postoperative radiotherapy. In this case report, we introduce a patient with aggressive recurred solid metastasis treated with repeated surgery and an individual radiotherapy approach in order to highlight that close mutual collaboration leads to a clear benefit for our patients. The local targeted radiotherapy with 35 Gy in 10 fractions was performed with the volumetric modulated arc technique, leading to more than 2.5 years of local control and survival without any of the side effects usually attributed to whole brain radiotherapy.

Salivary microRNAs identified by small RNA sequencing as potential predictors of response to intensity-modulated radiotherapy in head and neck cancer patients

PURPOSE

Progress in radiation therapy of head and neck squamous cell carcinomas (HNSCCs) is logically linked to the development of molecular predictors that would help to enhance individually tailored treatment. MicroRNA (miRNA) expression profiles in tumors have repeatedly been tested to optimize the molecular diagnostics of HNSCC. In addition to tumor tissues, miRNAs are stably present in body fluids, including saliva, and can thus be collected non-invasively. The aim of our current study was to evaluate whether salivary miRNAs have potential as response predictors in HNSCC patients treated with intensity modulated radiation therapy (IMRT).

METHODS

In total 48 HNSCC patients treated by definitive IMRT were enrolled in our prospective study. To identify predictive salivary miRNAs, we used small RNA sequencing in 14 saliva samples of HNSCC patients and qRT-PCR validation of selected miRNA candidates in an independent set of 34 patients.

RESULTS

We found that salivary miR-15a-5p and miR-15b-5p exhibited differential levels between patients with and without complete remission (p = 0.025 and p = 0.028, respectively). Subsequent Kaplan-Meier analysis confirmed that patients with higher levels of miR-15a-5p reached a significantly longer locoregional progression-free survival (LPFS) than those with low levels (p = 0.024). Finally, multivariate Cox regression analysis revealed that miR-15a-5p may serve as an independent predictive biomarker of LPFS in HNSCC patients treated with IMRT (HR 0.104; 95% CI 0.004-0.911; p = 0.04).

CONCLUSIONS

We conclude that salivary miR-15a-5p may represent a potential biomarker for individualized treatment decision-making in HNSCC patients.

Uncommon EGFR Mutations in Non-Small Cell Lung Cancer and Their Impact on the Treatment

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations play an important role in the pathogenesis of non-small cell lung cancer. Because these alterations are so-called targetable mutations, their identification is important in daily clinical practice. The diagnostic standard of EGFR mutations is currently based on polymerase chain reaction methods, particularly the quantitative real-time polymerase chain reaction. In recent years, new generation sequencing has become increasingly important. In patients with EGFR mutations, a significant improvement in therapeutic outcomes was achieved with the administration of targeted therapy using tyrosine kinase inhibitors. EGFR is composed of four domains: extracellular with a ligand binding site, a transmembrane domain, a cytoplasmic tyrosine kinase catalytic domain, and a C-terminal domain. The key structures of the tyrosine kinase domain responsible for signal activation and transmission are encoded within exons 18-21 on chromosome 7. EGFR mutations are highly heterogeneous. About 90% of EGFR mutations are deletions of exon 19 and point mutation L858R in exon 21. These are referred to as classic mutations. Approximately 10% of the total number of EGFR mutations is attributable to less frequent alterations in the EGFR gene. Due to the low incidence of non-small cell lung cancer with less frequent EGFR mutations, information on their predictive significance is still incomplete. Most of the data for the treatment of cases with uncommon mutations were gathered from retrospective analyses and evaluations of small cohorts.

PURPOSE

The aim of this review is to summarise the current options for diagnosing and treating non-small cell lung cancer patients with uncommon EGFR mutations. This work was supported by the MEYS - NPS I - LO1413 and MH CR - DRO (MMCI, 00209805). The authors declare they have no potential conflicts of interest concerning drugs, products, or&#8239;services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 2. 6. 2019 Accepted: 26. 8. 2019.

In silico study of pseudoprogression in glioblastoma: collaboration of radiologists and radiation oncologists in the estimation of extent of high dose RT region

BACKGROUND AND AIM

Oncologists play a vital role in the interpretation of radiographic results in glioblastoma patients. Molecular pathology and information on radiation treatment protocols among others are all important for accurate interpretation of radiology images. One important issue that may arise in interpreting such images is the phenomenon of tumor "pseudoprogression"; oncologists need to be able to distinguish this effect from true disease progression.Exact knowledge about the location of high-dose radiotherapy region is needed for valid determination of pseudoprogression according to RANO (Response Assessment in Neuro-Oncology) criteria in neurooncology. The aim of the present study was to evaluate the radiologists' understanding of a radiotherapy high-dose region in routine clinical practice since radiation oncologists do not always report 3-dimensional isodoses when ordering follow up imaging.

METHODS

Eight glioblastoma patients who underwent postresection radiotherapy were included in this study. Four radiologists worked with their pre-radiotherapy planning MR, however, they were blinded to RT target volumes which were defined by radiation oncologists according to current guidelines. The aim was to draw target volume for high dose RT fields (that is the region, where they would consider that there may be a pseudoprogression in future MRI scans). Many different indices describing structure differences were analyzed in comparison with original per-protocol RT target volumes.

RESULTS

The median volume for RT high dose field was 277 ccm (range 218 to 401 ccm) as defined per protocol by radiation oncologist and 87 ccm (range 32-338) as defined by radiologists (median difference of paired difference 31%, range 15-112%). The Median Dice index of similarity was 0.46 (range 0.14 - 0.78), the median Hausdorff distance 25 mm.

CONCLUSION

Continuing effort to improve education on specific procedures in RT and in radiology as well as automatic tools for exporting RT targets is needed in order to increase specificity and sensitivity in response evaluation.

P14.101 Glioblastoma survival outcomes related to cortical/neural stem cells regions

BACKGROUND

Subventricular brain zone (SVZ) and hippocampal regions are supposed to harbor astrocyte-like neural stem cells. While some tumors may arise from transformed SVZ stem cells, other may be initiated by neo-plastic transformation of non-SVZ progenitor cells or mature glial cells. Lim′s et al classification (Neuro-Oncology 2007) of initial glioblastoma location, related to these neural stem cells regions, was predictive for invasive and multifocal tumor phenotype. The aim of this retrospective single-institutional study is to evaluate the relations of this Lim classification on survival parameters in unselected cohort of glioblastoma patients.

MATERIAL AND METHODS

Patients treated between 2014–2017 were grouped according to initial location of their contrast enhancing lesion as follows: Lim1 (SVZ+⋯SVZ/hippocampal involvement and Cortex+⋯cortex involvement), Lim2 (SVZ+ and Cortex-), Lim3 (SVZ- and Cortex+) and Lim4 (SVZ- and Cortex-). All patients underwent radiotherapy, some patients were indicated to full treatment according to Stupp regimen (at least 3 cycles of adjuvant chemotherapy after postsurgery chemoradiotherapy).

RESULTS

In total, 144 patients were analyzed (94 men, mean age 59 years). 47 patients (30.5%) were treated according to Stupp regimen. Lim1 classification was presented in 74 (48%) patients, Lim2 in 22 (14.3%), Lim3 in 50 (32.5%) and Lim4 in 8 (5.2%) patients. Cortical structures (Lim1 and Lim3) were involved in 124 (80.5%) patients. Median overall survival was significantly better in patients treated according to Stupp regimen (23.3 vs. 8.6 months, p<0.001). Median overall survival differs in respective Lim groups: 12.3, 5.6, 11.8 and 6.6 months (p=0.07). Better survival was in patients with cortical involvement (Lim1+Lim3): 12.3 vs. 6.4 months (p=0.02), especially in subgroup of patients who were not treated according to Stupp regimen (8.9 vs. 4.4 months, p=0.02) vs. those after Stupp regimen (23 vs. 23.4 months, p=0.7).

CONCLUSION

Initial location of enhancing glioblastoma was prognostic for overall survival, with better outcomes in patients presented by involvement of cortical structures comparing to subventricular/hippocampal zones. Molecular patterns may further clarify potential effects of neural stem cells in glioma genesis mirrored in different clinical behavior and location of initial tumor. Supported by Ministry of Health of the Czech Republic, grant No. 18-03-00469

P14.107 Rapid early progression of glioblastoma is not related to cortical/neural stem cells regions

BACKGROUND

Rapid early progression (REP) of glioblastoma after surgery is quite often observed on pre-radiotherapy MR scan. Clinical and molecular biomarkers indicating increased risk of this REP may be of high clinical need. Subventricular brain zone (SVZ) and hippocampal regions are supposed to harbor astrocyte-like neural stem cells with tumors arising from these transformed SVZ stem cells dreaded to be of higher risk of REP. Lim′s et al classification of initial glioblastoma location related to these neural stem cells regions was predictive for invasive and multifocal tumor phenotype. The aim of this retrospective single-institutional study is to evaluate the relations of this Lim classification on REP in unselected cohort of glioblastoma patients.

MATERIAL AND METHODS

Patients treated by radiotherapy between 2014–2017 were grouped as follows: Lim1 (SVZ+⋯SVZ/hippocampal involvement and Cortex+⋯cortex involvement), Lim2 (SVZ+ and Cortex-), Lim3 (SVZ- and Cortex+) and Lim4 (SVZ- and Cortex-). Some patients were indicated to Stupp regimen. REP was defined on pre-radiotherapy MR as new distant lesion, progression of residuum, or new enhancement in postsurgery cavity.

RESULTS

In total, 144 patients were analyzed (94 men, mean age 59 years). 47 patients (30.5%) were treated according to Stupp regimen. Lim1 classification was presented in 74 (48%) patients, Lim2 in 22 (14.3%), Lim3 in 50 (32.5%) and Lim4 in 8 (5.2%) patients. Cortical structures (Lim1 and Lim3) were involved in 124 (80.5%) patients. Median overall survival was significantly better in patients treated according to Stupp regimen (23.3 vs. 8.6 months, p&lt;0.001) and in those without REP (18.5 vs. 10.2 months, p=0.001). REP was presented in 52% of 95 evaluable patients who underwent both post-surgery and pre-radiotherapy MR scans and there was no significant impact of time to start of radiotherapy. No significant relation between REP and Lim classification was observed (REP in 23/47 Lim1, in 8/13 Lim2, in 16/31 Lim3 and in 2/4 Lim4 patients).

CONCLUSION

Initial location of enhancing glioblastoma is not predictive for REP. Patients experiencing REP have significantly worse overall survival and modification of their management represents urgent unmet clinical need. Molecular and clinical biomarkers indicating increased risk of REP are needed. Supported by Ministry of Health of the Czech Republic, grant No. 18-03-00469.

MicroRNA-15b-5p Predicts Locoregional Relapse in Head and Neck Carcinoma Patients Treated With Intensity-modulated Radiotherapy

BACKGROUND/AIM

Head and neck cancers are a heterogenous group of epithelial tumors represented mainly by squamous cell carcinomas (HNSCC), which are the sixth most common type of cancer worldwide. Surgery together with radiotherapy (RT) is among the basic treatment modalities for most HNSCC patients. Various biomarkers aiming to predict patients' response to RT are currently investigated. The reason behind this effort is, on one hand, to distinguish radioresistant patients that show weak benefit from RT and, on the other hand, reduce the ionizing radiation dose in less aggressive radiosensitive HNSCC with possibly less acute or late toxicity.

MATERIALS AND METHODS

A total of 94 HNSCC patients treated by definitive intensity-modulated radiotherapy were included in our retrospective study. We used a global expression analysis of microRNAs (miRNAs) in 43 tumor samples and validated a series of selected miRNAs in an independent set of 51 tumors.

RESULTS

We identified miR-15b-5p to be differentially expressed between patients with short and long time of locoregional control (LRC). Kaplan-Meier analysis confirmed that HNSCC patients with higher expression of miR-15b-5p reach a significantly longer locoregional relapse-free survival compared to patients expressing low levels. Finally, multivariable Cox regression analysis revealed that miR-15b-5p is an independent predictive biomarker of LRC in HNSCC patients (HR=0.25; 95% CI=0.05-0.78; p<0.016).

CONCLUSION

miR-15b-5p represents a potentially helpful biomarker for individualized treatment decisions concerning the management of HNSCC patients.

Stereotactic Body Radiotherapy - Current Indications

BACKGROUND

Stereotactic body radiotherapy (SBRT) is used to treat localized tumor lesions and consists of applying high doses of radiation to a small number of fractions using specially equipped linear accelerators, modern immobilization devices, and imaging methods, which are considered special, advanced techniques in modern day radiotherapy. SBRT is a very well tolerated, non-invasive, short-term treatment that does not require hospitalization or any complicated preparation. Compared to standard radiotherapy techniques, SBRT allows, due to its precision, significantly higher doses to be applied to the target with less damage to surrounding healthy tissues. If dose constraints are not exceeded, the risk of damage to tissues and organs around the irradiated volume is reduced to minimum. The principle of SBRT is the application of ablative doses of radiation that cause necrosis of the irradiated tissue.

PURPOSE

The aim of this review is to provide a basic overview of SBRT indications, radiation doses used, and potential side effects. It is not intended to be a detailed description of treatment itself (such as discussion of patient fixation systems, management of respiratory movements, or image guided strategies of treatment). This review also discusses rarer indications for SBRT, such as pancreatic carcinoma or hepatocellular carcinoma.

CONCLUSION

Advances in image navigation, radiation planning, and dose application have enabled successful introduction of SBRT as a treatment regimen for many primary tumors and oligometastatic disease. If surgery is not possible or the patient refuses surgery, it is always reasonable to consider SBRT. SBRT has curative potential for the treatment of primary lung or prostate tumors. High-dose irradiation of oligometastases of various primary tumors can lead to long-term survival without disease symptoms, delay administration of toxic systemic therapies, and improve the quality of life of oncological patients. Key words radiotherapy - stereotactic body radiotherapy - review - ablative radiotherapy - lung cancer - prostate cancer - oligometastatic disease This work was supported in part by the Ministry of Health, Czech Republic - Conceptual Development of Research Organization (MMCI 00209805). The results of this research have been acquired within CEITEC 2020 (LQ1601) project with the financial contribution made by the Minis-try of Education, Youths and Sports of the Czech Republic within special support paid from the National Programme for Sustainability II funds. The authors declare they have no potential conflicts of interest concerning drugs, products, or&#8239;services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 30. 10. 2018 Accepted: 4. 11. 2018.