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Circulating cell-free DNA as predictor of pathological complete response in locally advanced rectal cancer patients undergoing preoperative chemoradiotherapy. Clin Transl Radiat Oncol 2022; 36:9-15. [PMID: 35733829 PMCID: PMC9207192 DOI: 10.1016/j.ctro.2022.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 11/28/2022] Open
Abstract
cfDNA could be a biomarker for tailored follow-up in locally advanced rectal cancer. Circulating cell-free DNA can be quantified by a rapid, and feasible DFA method. Low cfDNA levels at end of therapy were related to pathological complete response. ‘cfDNA responders’ with descending levels during therapy were associated with pCR. We propose cfDNA as a complimentary tool for patient selection for a W&W strategy.
Background The watch and wait (W&W) strategy is proposed for patients with locally advanced rectal cancer (LARC) achieving clinical complete response (cCR) after neoadjuvant radiotherapy. cCR is only in partial concordance with pathological complete response (pCR) due to persisting viable tumour cells. The aim was to investigate circulating-free-deoxyribonucleic-acid (cfDNA) as a biomarker for prediction of pCR. Materials and methods Patients treated with neoadjuvant radiotherapy for LARC, were included in a prospective biomarker study in Aarhus, Denmark from 2017 to 2020. Plasma cfDNA levels were analysed by a direct fluorescent assay (DFA). Surgical specimens were reviewed by pathologists to categorize response to cytotoxic therapy. Results In total, 76 patients were included with plasma available at baseline (n = 70), mid therapy (n = 50), and end of therapy (n = 54). Higher cfDNA levels were observed in LARC patients compared with healthy subjects (p < 0.01). By ROC analysis (AUC: 0.87 (95% CI, 0.81–0.92)) the optimal cut-off was 0.71 ng/µL for differentiation between healthy subjects and LARC patients. Thirteen patients obtained pCR with a median cfDNA level of 0.57 ng/µL at end of therapy. Patients with cfDNA levels at end of therapy below the cut-off (p < 0.02) and ‘cfDNA responders’ with descending levels greater than the 75th percentile during therapy had a significantly higher chance of pCR (p < 0.01). Conclusion This hypothesis generating study indicates that low cfDNA levels at end of treatment or ´cfDNA responderś might be associated with pCR. Quantification of cfDNA by the rapid and feasible DFA analysis could potentially facilitate personalized follow-up as a complementary tool to identify candidates for a W&W strategy.
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Key Words
- CRT, chemoradiotherapy
- DFA, direct fluorescent assay
- IMRT, intensity modulated radiotherapy
- LARC, locally advanced rectal cancer
- NGS, next generation sequencing
- RT, radiotherapy
- VMAT, volumetric modulated arc therapy
- W&W, watch and wait
- cCR, clinical complete response
- cfDNA, circulating cell free deoxyribonucleic acid
- ddPCR, digital droplet polymerase chain reaction
- ng/µL, nanogram per microliter.
- pCR, pathological complete response
- qPCR, quantitative polymerase chain reaction
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Evaluation of an automated template-based treatment planning system for radiotherapy of anal, rectal and prostate cancer. Tech Innov Patient Support Radiat Oncol 2022; 22:30-36. [PMID: 35464888 PMCID: PMC9020095 DOI: 10.1016/j.tipsro.2022.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/11/2022] [Accepted: 04/05/2022] [Indexed: 11/21/2022] Open
Abstract
Automated treatment planning system compared to manual planning. Equivalent plan quality between VMAT manually generated- and IMRT automatically generated plans. Evaluation of anal, prostate and rectum treatment plans. Generation of highly consistent IMRT automated plan within 2 to 3.5 min.
Background and purpose The Ethos system has enabled online adaptive radiotherapy (oART) by implementing an automated treatment planning system (aTPS) for both intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) plan creation. The purpose of this study is to evaluate the quality of aTPS plans in the pelvic region. Material and Methods Sixty patients with anal (n = 20), rectal (n = 20) or prostate (n = 20) cancer were retrospectively re-planned with the aTPS. Three IMRT (7-, 9- and 12-field) and two VMAT (2 and 3 arc) automatically generated plans (APs) were created per patient. The duration of the automated plan generation was registered. The best IMRT-AP and VMAT-AP for each patient were selected based on target coverage and dose to organs at risk (OARs). The AP quality was analyzed and compared to corresponding clinically accepted and manually generated VMAT plans (MPs) using several clinically relevant dose metrics. Calculation-based pre-treatment plan quality assurance (QA) was performed for all plans. Results The median total duration to generate the five APs with the aTPS was 55 min, 39 min and 35 min for anal, prostate and rectal plans, respectively. The target coverage and the OAR sparing were equivalent for IMRT-APs and VMAT-MPs, while VMAT-Aps. demonstrated lower target dose homogeneity and higher dose to some OARs. Both conformity and homogeneity index were equivalent (rectal) or better (anal and prostate) for IMRT-APs compared to VMAT-MPs. All plans passed the patient-specific QA tolerance limit. Conclusions The aTPS generates plans comparable to MPs within a short time-frame which is highly relevant for oART treatments.
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Key Words
- AP, automatically generated plan
- Automated treatment planning
- CN, conformity number
- CT, computed tomography
- CTV, clinical target volume
- DVH, dose volume histogram
- FFF, flattening filter free
- GTV, gross tumor volume
- HI, homogeneity index
- IMRT, intensity modulated radiotherapy
- Intelligent optimization engine
- KPB, knowledge-based planning
- Linac, Linear accelerators
- MCO, multi-criteria optimization
- MLC, multileaf collimator
- MP, manually-generated plan
- MR, magnetic resonance
- MU, Monitor Unit
- OAR, Organ at risk
- Online adaptive radiotherapy
- PTV, planning target volume
- Pelvic cancer
- Plan quality
- QA, Quality assurance
- SD, standard deviation
- Template-based Ethos TPS
- VMAT, volumetric arc radiotherapy
- aTPS, automated treatment planning system
- oART, online adaptive radiotherapy
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High-dose-rate brachytherapy boost for locally advanced cervical cancer: Oncological outcome and toxicity analysis of 4 fractionation schemes. Clin Transl Radiat Oncol 2021; 32:15-23. [PMID: 34816022 PMCID: PMC8592834 DOI: 10.1016/j.ctro.2021.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/15/2021] [Accepted: 10/15/2021] [Indexed: 12/04/2022] Open
Abstract
Brachytherapy boost is a standard of care for locally advanced cervical cancer. High-dose-rate brachytherapy (HDR-BT) boost procedure is not standardized. The number of implants, fractions, doses and imaging differ in literature. Bi-fractionated HDR-BT in 1 implant is feasible with good oncological outcome. Bi-fractionated HDR-BT dose escalation slightly increases acute toxicity.
Purpose Brachytherapy (BT) boost after radio-chemotherapy (RCT) is a standard of care in the management of locally advanced cervical cancer (LACC). As there is no consensus on high-dose-rate (HDR) BT fractionation schemes, our aim was to report the oncological outcome and toxicity profile of four different schemes using twice-a-day (BID) HDR-BT. Patients and methods This was an observational, retrospective, single institution study for patients with LACC receiving a HDR-BT boost. The latter was performed with a single implant and single imaging done on day 1. The different fractionation schemes were: 7 Gy + 4x3.5 Gy (group 1); 7 Gy + 4x4.5 Gy (group 2); 3x7Gy (group 3) and 3x8Gy (group 4). Local (LFS), nodal (NFS) and metastatic (MFS) recurrence-free survival as well as progression-free survival (PFS) and overall survival (OS) were analyzed. Acute (≤6 months) and late toxicities (>6 months) were reported. Results From 2007 to 2018, 191 patients were included. Median follow-up was 57 months [45–132] and median EQD210D90CTVHR was 84, 82 and 90 Gy for groups 2, 3 and 4 respectively (dosimetric data missing for group 1). The 5-year LFS, NFS, MFS, PFS and OS were 85% [81–90], 83% [79–86], 70% [67–73], 61% [57–64] and 75% [69–78] respectively, with no significant difference between the groups. EQD210D90CTVHR < 85 Gy was a prognostic factor for local recurrence in univariate analysis (p = 0.045). The rates of acute/late grade ≥ 2 urinary, digestive and gynecological toxicities were 9%/15%, 3%/15% and 9%/25% respectively. Conclusion Bi-fractionated HDR-BT boost seems feasible with good oncological outcome and slightly more toxicity after dose escalation.
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Key Words
- BED, biologically effective dose
- BID, twice-a-day
- BMI, body-mass index
- BT, brachytherapy
- Brachytherapy
- CT, computerized tomography
- CTCAE, common terminology criteria for adverse events
- CTV, clinical target volume
- Cervical cancer
- EBRT, external beam radiotherapy
- EMBRACE, image guided intensity modulated External beam radiochemotherapy and MRI based Adaptative BRAchytherapy in locally advanced CErvical cancer
- EQD2Gy, equivalent dose at 2 Gy
- ESTRO, European Society for Radiotherapy and Oncology
- FIGO, International Federation of Gynecology and Obstetrics
- Fractionation scheme
- GEC, groupe européen de curiethérapie
- GTV, gross tumor volume
- HDR, high-dose-rate
- HIV, human immunodeficiency virus
- HR, high-risk
- High-dose-rate
- ICRU, International Commission on Radiation Units and measurements
- IGABT, image-guided adaptative brachytherapy
- IMRT, intensity modulated radiotherapy
- IR, intermediate-risk
- LACC, locally advanced cervical cancer
- LDR, low-dose-rate
- LFS, local recurrence-free survival
- LQ, linear quadratic
- MFS, metastatic recurrence-free survival
- MFU, median follow up
- MRI, magnetic resonance imaging
- NA, not available
- NCI, national cancer institute
- NFS, nodal recurrence-free survival
- OAR, organs at risk
- OS, overall survival
- OTT, overall treatment time
- PDR, pulsed-dose-rate
- PET, positron emission tomography
- PFS, progression-free survival
- PTV, planning target volume
- RCT, radio-chemotherapy
- SCC, squamous cell cancer
- SEER, surveillance, epidemiology and end results
- pt, patient
- pts, patients
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Intensity modulated radiotherapy for anal canal squamous cell carcinoma: A 16-year single institution experience. Clin Transl Radiat Oncol 2021; 28:17-23. [PMID: 33732911 PMCID: PMC7943964 DOI: 10.1016/j.ctro.2021.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 02/01/2021] [Accepted: 02/05/2021] [Indexed: 12/28/2022] Open
Abstract
Introduction To report long-term efficacy and adverse events (AEs) associated with intensity modulated radiotherapy (IMRT) for patients with anal canal squamous cell carcinoma (ASCC). Materials and methods This was a retrospective review of patients with ASCC who received curative-intent IMRT and concurrent chemotherapy (98%) between 2003 and 2019. Overall survival (OS), colostomy-free survival (CFS), and progression-free survival (PFS) were estimated using the Kaplan-Meier method. The cumulative incidence of local recurrence (LR), locoregional recurrence (LRR), and distant metastasis (DM) were reported. Acute and late AEs were recorded per National Cancer Institute Common Terminology Criteria for AEs. Results 127 patients were included. The median patient age was 63 years (interquartile range [IQR] 55-69) and 79% of patients were female. 33% of patients had T3-4 disease and 68% had clinically involved pelvic or inguinal lymph nodes (LNs).The median patient follow-up was 47 months (IQR: 28-89 months). The estimated 4-year OS, CFS, and PFS were 81% (95% confidence interval [CI]: 73%-89%), 77% (95% CI: 68%-86%), and 78% (95% CI: 70%-86%), respectively. The 4-year cumulative incidences of LR, LRR, and DM were 3% (95% CI: 1%-9%), 9% (95% CI: 5%-17%), and 10% (95% CI: 6%-18%), respectively. Overall treatment duration greater than 39 days was associated with an increased risk of LRR (Hazard Ratio [HR]: 5.2, 95% CI: 1.4-19.5, p = 0.015). The most common grade 3+ acute AEs included hematologic (31%), gastrointestinal (GI) (17%), dermatologic (16%), and pain (15%). Grade 3+ late AEs included: GI (3%), genitourinary (GU) (2%), and pain (1%). Current smokers were more likely to experience grade 3+ acute dermatologic toxicity compared to former or never smokers (34% vs. 7%, p < 0.001). Conclusions IMRT was associated with favorable toxicity rates and long-term efficacy. These data support the continued utilization of IMRT as the preferred treatment technique for patients with ASCC.
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Key Words
- 3DCRT, 3-dimensional conformal radiotherapy
- 5-FU, 5-fluorouracil
- ACT II, United Kingdom Anal Cancer Trial II
- AE, adverse events
- ASCC, anal canal squamous cell carcinoma
- Anal cancer
- BED, biologically effective dose
- CFS, colostomy-free survival
- CI, confidence interval
- CRT, chemoradiotherapy
- CTCAE v 4.0, common terminology criteria for adverse events version 4.0
- CTV, clinical target volume
- DM, distant metastasis
- DP-IMRT, dose-painted intensity modulated radiotherapy
- DVH, dose-volume histogram
- G, grade
- GI, gastrointestinal
- GU, genitourinary
- HIV, human immunodeficiency virus
- HR, hazard ratio
- IMRT
- IMRT, intensity modulated radiotherapy
- IQR, interquartile range
- LN, lymph node
- LR, local recurrence
- LRR, locoregional recurrence
- MMC, mitomycin-C
- OS, overall survival
- PFS, progression-free survival
- PTV, planning target volume
- RT, radiotherapy
- RTOG, Radiation Therapy Oncology Group
- Radiation
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Prolonging deep inspiration breath-hold time to 3 min during radiotherapy, a simple solution. Clin Transl Radiat Oncol 2021; 28:10-16. [PMID: 33732910 PMCID: PMC7941008 DOI: 10.1016/j.ctro.2021.02.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 01/07/2023] Open
Abstract
A new protocol was developped to prolong deep inspiration breath-holds. Multiple prolonged breath-holds are achievable with minimal side effects. DIBH was prolonged to 3 min using HFNO and hyperventilation in breast cancer patients.
Background and purpose Deep inspiration breath-hold is an established technique to reduce heart dose during breast cancer radiotherapy. However, modern breast cancer radiotherapy techniques with lymph node irradiation often require long beam-on times of up to 5 min. Therefore, the combination with deep inspiration breath-hold (DIBH) becomes challenging. A simple support technique for longer duration deep inspiration breath-hold (L-DIBH), feasible for daily use at the radiotherapy department, is required to maximize heart sparing. Materials and methods At our department, a new protocol for multiple L-DIBH of at least 2 min and 30 s was developed on 32 healthy volunteers and validated on 8 breast cancer patients during radiotherapy treatment, using a pragmatic process of iterative development, including all major stakeholders. Each participant performed 12 L-DIBHs, on 4 different days. Different methods of pre-oxygenation and voluntary hyperventilation were tested, and scored on L-DIBH duration, ease of use, and comfort. Results Based on 384 L-DIBHs from 32 healthy volunteers, voluntary hyperventilation for 3 min whilst receiving high-flow nasal oxygen at 40 L/min was the most promising technique. During validation, the median L-DIBH duration in prone position of 8 breast cancer patients improved from 59 s without support to 3 min and 9 s using the technique (p < 0.001). Conclusion A new and simple L-DIBH protocol was developed feasible for daily use at the radiotherapy center.
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Recurrence of head and neck squamous cell carcinoma in relation to high-risk treatment volume. Clin Transl Radiat Oncol 2021; 27:139-146. [PMID: 33665383 PMCID: PMC7902285 DOI: 10.1016/j.ctro.2021.01.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/30/2021] [Accepted: 01/31/2021] [Indexed: 12/01/2022] Open
Abstract
Distribution of recurrent HNSCC in relation to radiotherapy volume was evaluated. Both p16 positive and negative HNSCC recur in high-risk treatment volume. This indicates potential failure of multimodality imaging to disclose significant disease. A need for biomarkers other than p16 to predict radiosensitivity continues to exist.
Background Locoregional recurrence remains a major cause of failure in head and neck squamous cell carcinoma (HNSCC). Human papilloma virus (HPV)-associated HNSCCs generally have a good prognosis but may recur even after standard photon radiotherapy (RT). Another incentive in observing patterns of recurrence is increased use of highly conformal techniques such as proton therapy. We therefore studied geographic distribution of recurrent tumors in relation to the high-risk treatment volume in a cohort of patients with HNSCC receiving combined modality therapy. Methods Medical records of 508 patients diagnosed with HNSCC in 2010–2015 were reviewed. We identified a subgroup that had local and/or regional recurrence at hybrid positron emission tomography (PET)/computed tomography (CT) and/or magnetic resonance imaging (MRI). We adapted p16 as a surrogate marker for HPV-positivity and only patients with known p16 status were eligible for a detailed analysis where recurrent tumor was copied on the planning CT and the dose received by the recurrent tumor volume was determined using dose-volume histograms. Results Twenty-five patients who had received either cisplatin (n = 23) or cetuximab-enhanced (n = 2) RT were identified. 31 locoregional recurrent tumors were detected among 18 p16 negative and 7 p16 positive patients. Of recurrent tumors 14 (45%) were classified as in-field, 5 (16%) as marginal miss, and 12 (39%) as true miss. p16 positive patients had 4 in-field, 2 marginal, and 1 true miss. By contrast, p16 negative patients had 10 in-field, 3 marginal, and 11 true miss recurrences. Conclusions Both p16 positive and negative HNSCC recur in high-risk treatment volume despite the common view of high radiosensitivity of the former. Biomarkers predicting radioresistance should be characterized in p16 positive tumors before widely embarking on de-escalated CRT protocols. Another concern is how to decrease the number of true or marginal misses in p16 negative cases despite multimodality imaging-based target delineation.
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Key Words
- 18F-fluorodeoxyglucose, FDG
- CRT, chemoradiotherapy
- CT, computed tomography
- DFS, disease-free survival
- HNSCC, head and neck squamous cell carcinoma
- HPV, human papilloma virus
- Head and neck cancer
- Human papillomavirus
- IMRT, intensity modulated radiotherapy
- In-field recurrence
- MRI, magnetic resonance imaging
- OS, overall survival
- PET, positron emission tomography
- RT, radiation therapy
- Radioresistance
- Tumor recurrence
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Transitioning from conformal radiotherapy to intensity-modulated radiotherapy after radical prostatectomy: Clinical benefit, oncologic outcomes and incidence of gastrointestinal and urinary toxicities. Rep Pract Oncol Radiother 2020; 25:568-573. [PMID: 32494230 DOI: 10.1016/j.rpor.2020.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 04/05/2020] [Accepted: 04/23/2020] [Indexed: 11/22/2022] Open
Abstract
Aim The purpose of this study was to review genitourinary (GU) and gastrointestinal (GI) toxicity associated with high-dose radiotherapy (RT) delivered with 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) or volumetric arc therapy (VMAT) following radical prostatectomy (RP). Background RP is a therapeutic option for the management of prostate cancer (PrCa). When assessing postoperative RT techniques for PrCa, the published literature focuses on patients treated with 2-dimensional conventional methods without reflecting the implementation of 3D-CRT, IMRT, or VMAT. Materials and methods A total of 83 patients were included in this analysis; 30 patients received 3D-CRT, and 53 patients received IMRT/VMAT. Acute and late symptoms of the GU and lower GI tract were retrospectively graded according to the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer radiation toxicity grading systems. The relapse failure-free rate and overall survival were also evaluated. Results The rate of acute GU toxicity was 9.4% vs. 13.3% for the IMRT/VMAT and 3D-CRT groups (p = 0.583). The 5-year actuarial rates of late GI toxicity for IMRT/VMAT and 3D-CRT treatments were 1.9% and 6.7%, respectively. The rate of late GU toxicity for the IMRT/VMAT and 3D-CRT treatment groups was 7.5% and 16.6%, respectively (p = 0.199). We found no association between acute or late toxicity and the RT technique in univariate and multivariate analyses. Conclusion Postprostatectomy IMRT/VMAT and 3D-CRT achieved similar morbidity and cancer control outcomes. The clinical benefit of highly conformal techniques in this setting is unclear although formal analysis is needed.
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Key Words
- 3D-CRT, 3-dimensionalconformal radiotherapy
- ADT, androgen deprivation therapy
- ART, adjuvant radiotherapy
- BCR, biochemical recurrence
- CBCT, cone-beam computed tomography
- CTV, clinical target volume
- EORTC, European Organisation for Research and Treatment of Cancer
- GI, gastrointestinal
- GU, genitourinary
- Gastrointestinal toxicity
- IMRT, intensity modulated radiotherapy
- NCCN, National Comprehensive Cancer Network
- OS, overall survival
- PSA, prostate-specific antigen
- Postoperative radiotherapy
- PrCa, prostate cancer
- Prostate cancer
- RFF, relapse failure-free
- RP, radical prostatectomy
- RT, radiotherapy
- RTOG, radiation therapy oncology group
- SRT, salvage radiotherapy
- Urinary toxicity
- VMAT, volumetric arc therapy
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Multiple sclerosis as differential diagnosis of radionecrosis for post-irradiation brain lesions: A case report. Clin Transl Radiat Oncol 2020; 21:44-48. [PMID: 32021912 PMCID: PMC6993054 DOI: 10.1016/j.ctro.2020.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/07/2020] [Accepted: 01/07/2020] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Demyelination can occur after brain radiotherapy in tissue adjacent to irradiated tumours. To date, no correlation has been found between conventional-dose radiotherapy and the development of multiple sclerosis, but radiotherapy could be a triggering factor among women with known multiple sclerosis. To the best of our knowledge, this is the first well-documented case of this association with a dosimetric analysis. CASE PRESENTATION The case we report here describes the development of multiple sclerosis in a 36-year-old woman without significant past medical history 3 months after the last session of fractionated stereotactic radiotherapy for a pituitary macroadenoma. Our dosimetric analysis suggests that all the multiple sclerosis lesions occurred in the brain regions irradiated with a mean biologically effective dose (BED2) of 33.9 Gy (27.3-49.6 Gy). CONCLUSION Consequently special caution towards radiotherapy is required among patients with demyelinating illnesses or for 35-45-year-old women who are at risk. In addition, multiple sclerosis lesions can look like metastases. We should therefore keep differential diagnoses in mind in order not to make mistakes that would delay treatment.
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Key Words
- BED, biologically effective dose
- CSF, cerebrospinal fluid
- CT, computed tomography
- CTV, clinical target volume
- Differential diagnosis
- Dosimetric analysis
- GTV, gross tumor volume
- Gy, gray
- IMRT, intensity modulated radiotherapy
- LS, Lhermitte’s syndrome
- MRI, magnetic resonance imagery
- Multiple sclerosis
- PTV, planning target volume
- Radiotherapy
- VMAT, volumetric modulated arctherapy
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Incidence of contralateral regional failure in the electively irradiated contralateral neck of patients with head and neck squamous cell carcinoma. Clin Transl Radiat Oncol 2019; 17:7-13. [PMID: 31061901 PMCID: PMC6488558 DOI: 10.1016/j.ctro.2019.04.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 04/18/2019] [Indexed: 12/18/2022] Open
Abstract
Contralateral regional failure still occurs after bilateral nodal irradiation. No significant predictive factors were identified for contralateral regional failure. Overall survival did not differ between patients with ipsi- or contralateral failure.
Background The vast majority of patients with head and neck squamous cell carcinoma (HNSCC) routinely undergo elective nodal irradiation (ENI) to both sides of the neck. Little is known about the extent to which bilateral ENI prevents regional failure (RF) and contralateral RF (cRF) in particular, while such knowledge is necessary to evaluate the results of more selective approaches like unilateral ENI. We investigated the rate and pattern of RF after bilateral ENI, the rate of cRF in the electively irradiated contralateral neck, and tried to identify risk factors for development of cRF. Materials and methods Retrospective cohort study of a consecutive series of 605 patients with T1-4N0-3 HNSCC treated between 2008 and 2017 with primary (chemo)radiation and bilateral ENI. Results Median follow-up was 43 months (range 1.4–126). Three-year cumulative incidence of RF was 12.7%. Three-year cumulative incidences of ipsilateral RF (iRF) and cRF were 10.6% and 2.8%, respectively. All cRF occurred within the electively treated volume. Salvage treatment was possible in 65% and 59% of patients with iRF and cRF, respectively (p = 0.746). The 3-year overall survival rates after RF in patients with iRF and cRF were 27.4% and 41.2%, respectively (p = 0.713). Three-year cancer-specific survival rates were 31.6% and 48.1%, respectively (p = 0.634). In multivariate analysis, no significant predictive factors were identified for cRF after bilateral ENI. Conclusion Contralateral regional failure is rare, but still occurs in 2.8% of patients treated with bilateral ENI. The possibilities for salvage treatment, the rates of overall survival and cancer-specific survival were comparable to patients with iRF.
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Key Words
- Bilateral elective irradiation
- CSS, cancer specific survival
- CTV, clinical target volume
- Contralateral regional failure
- DM, distant metastasis
- ENI, elective nodal irradiation
- GTV, gross tumor volume
- HNSCC, head and neck squamous cell carcinoma
- HPV, human papilloma virus
- Head and neck cancer
- IMRT, intensity modulated radiotherapy
- LF, local failure
- OPC, oropharyngeal cancer
- OS, overall survival
- PTV, planning target volume
- RF, regional failure
- Unilateral elective irradiation
- VMAT, volumetric arc therapy
- cRF, contralateral regional failure
- iRF, ipsilateral regional failure
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Geometric and dosimetric evaluation of the differences between rigid and deformable registration to assess interfraction motion during pelvic radiotherapy. Phys Imaging Radiat Oncol 2019; 9:97-102. [PMID: 33458433 PMCID: PMC7807633 DOI: 10.1016/j.phro.2019.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 02/26/2019] [Accepted: 02/27/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND AND PURPOSE Appropriate internal margins are essential to avoid a geographical miss in intensity-modulated radiation therapy (IMRT) for endometrial cancer (EC). This study evaluated interfraction target motion using rigid and non-rigid approximation strategies and calculated internal margins based on random and systematic errors using traditional rigid margin recipes. Dosimetric impact of target motion was also investigated. MATERIALS AND METHODS Cone beam CTs (CBCTs) were acquired days 1-4 and then weekly in 17 patients receiving adjuvant IMRT for EC; a total of 169 CBCTs were analysed. Interfraction motion for the clinical target volume vaginal vault and upper vagina (CTVv) was measured using bony landmarks and deformation vector field displacement (DVFD) within a 1 mm internal wall of CTVv. Patient and population systematic and random errors were estimated and margins calculated. Delivered dose to the CTVv and organs at risk was estimated. RESULTS There was a significant difference in target motion assessment using the different registration strategies (p < 0.05). DVFD up to 30 mm occurred in the anterior/posterior direction, which was not accounted for in PTV margins using rigid margin recipes. Underdosing of CTVv D95% occurred in three patients who had substantial reductions in rectal volume (RV) during treatment. RV relative to the planning CT was moderately correlated with anterior/posterior displacement (r = 0.6) and mean relative RV during treatment was strongly correlated with mean relative RV at CBCT acquired days 1-3 (r = 0.8). CONCLUSION Complex and extensive geometric changes occur to the CTVv, which are not accounted for in margin recipes using rigid approximation. Contemporary margin recipes and adaptive treatment planning based on non-rigid approximation are recommended.
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Key Words
- CBCT, cone beam CT
- CTVv, clinical target volume vaginal vault and upper vagina
- DIR, deformable image registration
- DSC, dice similarity coefficient
- DVFD, deformation vector field displacement
- EBRT, external beam radiotherapy
- EC, endometrial cancer
- IMRT, intensity modulated radiotherapy
- MDA, mean distance to agreement
- OARs, organs at risk
- RV, rectal volume
- pCT, planning CT
- Σ, systematic
- σ, random
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Immobilization versus no immobilization for pelvic external beam radiotherapy. Rep Pract Oncol Radiother 2018; 23:233-241. [PMID: 29991927 DOI: 10.1016/j.rpor.2018.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 12/23/2017] [Accepted: 04/12/2018] [Indexed: 10/16/2022] Open
Abstract
Aim To identify the most reproducible technique of patient positioning and immobilization during pelvic radiotherapy. Background Radiotherapy plays an important role in the treatment of pelvic malignancies. Errors in positioning of patient are an integral component of treatment. The present study compares two methods of immobilization with no immobilization with an aim of identifying the most reproducible method. Materials and methods 65 consecutive patients receiving pelvic external beam radiotherapy were retrospectively analyzed. 30, 21 and 14 patients were treated with no-immobilization with a leg separator, whole body vacuum bag cushion (VBC) and six point aquaplast immobilization system, respectively. The systematic error, random error and the planning target volume (PTV) margins were calculated for all the three techniques and statistically analyzed. Results The systematic errors were the highest in the VBC and random errors were the highest in the aquaplast group. Both systematic and random errors were the lowest in patients treated with no-immobilization. 3D Systematic error (mm, mean ± 1SD) was 4.31 ± 3.84, 3.39 ± 1.71 and 2.42 ± 0.97 for VBC, aquaplast and no-immobilization, respectively. 3D random error (mm, 1SD) was 2.96, 3.59 and 1.39 for VBC, aquaplast and no-immobilization, respectively. The differences were statistically significant between all the three groups. The calculated PTV margins were the smallest for the no-immobilization technique with 4.56, 4.69 and 4.59 mm, respectively, in x, y and z axes, respectively. Conclusions Among the three techniques, no-immobilization technique with leg separator was the most reproducible technique with the smallest PTV margins. For obvious reasons, this technique is the least time consuming and most economically viable in developing countries.
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Uptake of Prostate-Specific Membrane Antigen (PSMA) in adenoid cystic carcinoma - Is PSMA-PET-CT a helpful tool in radiation oncology? Clin Transl Radiat Oncol 2017; 7:79-82. [PMID: 29594233 PMCID: PMC5862661 DOI: 10.1016/j.ctro.2017.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/02/2017] [Accepted: 10/07/2017] [Indexed: 10/29/2022] Open
Abstract
This case report shows the high PSMA-uptake in a patient with an adenoid cystic carcinoma of the maxillary sinus. Due to the intense ligand-uptake additional information for target volume delineation was obtained and the Treatment plan for bimodal radiotherapy with carbon ions was adapted accordingly.
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Key Words
- ACC, Adenoid cystic carcinoma
- CTCAE, Common terminology criteria of adverse events
- HIT, Heidelberg Ion Beam Therapy Center
- IHC, Immunohistochemistry
- IMRT, intensity modulated radiotherapy
- PET-CT, Positron emission tomography-computed tomography
- PSMA, Prostate-Specific Membrane Antigen
- RBE, Relative Biological Effectiveness
- RECIST, Response Evaluation Criteria In Solid Tumors
- RT, radiotherapy
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