Management of lateral pelvic lymph nodes in rectal cancer: Is it time to reach an Agreement?

In this editorial, we proceed to comment on the article by Chua et al, addressing the management of metastatic lateral pelvic lymph nodes (mLLN) in stage II/III rectal cancer patients below the peritoneal reflection. The treatment of this nodal area sparks significant controversy due to the strategic differences followed by Eastern and Western physicians, albeit with a higher degree of convergence in recent years. The dissection of lateral pelvic lymph nodes without neoadjuvant therapy is a standard practice in Eastern countries. In contrast, in the West, preference leans towards opting for neoadjuvant therapy with chemoradiotherapy or radiotherapy, that would cover the treatment of this area without the need to add the dissection of these nodes to the total mesorectal excision. In the presence of high-risk nodal characteristics for mLLN related to radiological imaging and lack of response to neoadjuvant therapy, the risk of lateral local recurrence increases, suggesting the appropriate selection of strategies to reduce the risk of recurrence in each patient profile. Despite the heterogeneous and retrospective nature of studies addressing this area, an international consensus is necessary to approach this clinical scenario uniformly.

Docetaxel Provides Oncological Benefits in the Era of New-Generation Androgen Receptor Inhibitors - or Is Three a Crowd?

In recent years, several systemic therapies have been introduced for metastatic hormone-sensitive prostate cancer, including androgen deprivation therapy (ADT) combined with docetaxel (Doc) and/or new-generation androgen receptor signaling inhibitors (ARSI). Trials evaluating ADT + ARSI have consistently demonstrated an overall survival (OS) benefit for doublet therapy over ADT alone. Similarly, the STOPCaP meta-analysis showed an OS benefit in favor of ADT + Doc versus ADT alone. ARSI, Doc, and ADT have different antitumor mechanisms, thus potentiating the effect of combination therapy. Two randomized trials showed that the addition of ARSI to ADT + Doc improves OS, especially for synchronous high-volume disease. However, the real question about triplet therapy remains unanswered: whether combining Doc with ARSI improves outcomes compared to ADT + ARSI. As there are no head-to-head comparisons, this narrative review aims to summarize the current evidence regarding triplet therapy versus doublet therapy including ADT+ ARSI.

A Phase 2 Randomized Open-label Study of Oral Darolutamide Monotherapy Versus Androgen Deprivation Therapy in Men with Hormone-sensitive Prostate Cancer (EORTC-GUCG 1532)

BACKGROUND AND OBJECTIVE

Darolutamide is an androgen receptor inhibitor that increases overall survival in combination with androgen deprivation therapy (ADT) in patients with metastatic hormone-sensitive and nonmetastatic castration-resistant prostate cancer (PCa). This phase 2 study assessed the efficacy and safety of darolutamide as monotherapy without ADT in patients with eugonadal testosterone levels.

METHODS

This was a 24-wk, open-label, randomized study of patients with hormone-sensitive, histologically confirmed PCa requiring gonadotropin-releasing hormone (GnRH); an Eastern Cooperative Oncology Group performance status score of 0/1; and life expectancy >1 yr. All patients received darolutamide 600 mg bid or a commercially available GnRH analog. The primary endpoint is a prostate-specific antigen (PSA) response, defined as a ≥80% decline at week 24 relative to baseline in the darolutamide study arm. The GnRH arm is used as an internal control. The secondary endpoints included changes in T levels, safety/tolerability, and quality of life.

KEY FINDINGS AND LIMITATIONS

Among 61 men enrolled, the median (range) age was 72 yr (53-86 yr); 42.6% of them had metastases. In the darolutamide arm, the evaluable population with available PSA values at baseline and week 24 consisted of 23 patients. Twenty-three (100%) evaluable darolutamide patients achieved a PSA decline of >80% at week 24 (primary endpoint), with a median (range) decrease of -99.1% (-91.9%, -100%). Serum T levels increased by a median (range) of 44.3 (5.7-144.0) at week 24, compared with baseline. In the darolutamide arm, 48.4% of men reported drug-related adverse events (AEs; mostly grade 1 or 2). The most frequent treatment-emergent AEs included gynecomastia (35.5%), fatigue (12.9%), hot flush (12.9%), and hypertension (12.9%). Health-related quality of life measures are descriptive, and GnRH arm results will be presented as an internal reference.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Darolutamide monotherapy was associated with a significant PSA response in nearly all men with hormone-naïve PCa. Testosterone-level changes and most common AEs (gynecomastia, fatigue, hypertension, and hot flush) were consistent with potent androgen receptor inhibition.

PATIENT SUMMARY

In this study, we report the first use of darolutamide, a novel antiandrogen, as monotherapy without androgen deprivation therapy (ADT). The study shows that darolutamide induce a profound suppression of prostate-specific antigen in all patients, with a safety profile different from that of ADT.

Novel Approaches in the Systemic Management of High-Risk Prostate Cancer

Locally advanced prostate cancer comprises approximately 20% of new prostate cancer diagnoses. For these patients, international guidelines recommend treatment with radiotherapy (RT) to the prostate in combination with long-term (2-3 years) androgen deprivation therapy (ADT), or radical prostatectomy in combination with extended pelvic lymph node dissection (PLND) as another treatment option for selected patients as part of multimodal therapy. Improvements in overall survival with docetaxel or an androgen receptor signaling inhibitor have been achieved in patients with metastatic castration sensitive or castration resistant prostate cancer. However, the role of systemic therapy combinations for high risk and/or unfavorable prostate cancer is unclear. In this context, the aim of this review is to assess the current evidence for systemic treatment combinations as part of primary definitive therapy in patients with high-risk localized prostate cancer.

Jorge clinical study: 10-year outcomes of risk-adapted radiotherapy defined by multiparametric MRI for prostate cancer

PURPOSE

To analyze the 10-year biochemical relapse-free survival (BRFS), locoregional relapse-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS) in patients diagnosed with localized prostate adenocarcinoma treated with radiotherapy (RT) ± androgen deprivation therapy (ADT), according to the risk groups based on multiparametric magnetic resonance imaging (mpMRI) instead of digital rectal exam (DRE).

METHODS

We retrospectively evaluated 140 consecutive patients diagnosed with localized prostate adenocarcinoma, stratified into different risk groups-low (LR), intermediate (IR), and high (HR) by mpMRI results.

RESULTS

After a median follow-up of 104 months, in LR group (n = 15), 10-year BRFS was 86.7%, 10-year LRFS was 86.7%, 10-year MFS was 93.3%, and 10-year OS was 100%. In IR group (n = 80), 10-year BRFS was 80.5%, 10-year LRFS was 86.1%, 10-year MFS was 92.6%, and 10-year OS was 76%. In HR group (n = 45), 10-year BRFS was 72.8%, 10-year LRFS was 78.7%, 10-year MFS was 82.1%, and 10-year OS was 77% (2 deaths from prostate cancer). According to mpMRI results, 36 (25.7%) patients change the risk group and 125 (89.28%) patients change the TNM stage. There was a trend for higher metastatic relapse in patients who switched from IR to HR (due to mpMRI) versus the patients who remained in the IR (20%, vs. 1.81% p = 0.059). Multivariate analysis showed that locoregional relapse was strongly associated with distant relapse (OR = 9.28; 95%CI: 2.60-33.31). There were no cases of acute grade 3 toxicity. Late grade 3 genitourinary, gastrointestinal, and sexual toxicity were 2.8%, 0.7%, and 1.2%, respectively.

CONCLUSION

This is the first study with a 10-year median follow-up of patients diagnosed with localized prostate cancer treated with radiotherapy according to the risk groups established by mpMRI. Our findings show that mpMRI is a key tool to diagnose and establish risk groups in these patients, to optimize their treatment.

Total neoadjuvant therapy approach for the treatment of locally advanced rectal cancer. Where do we stand?

BACKGROUND

for the management of locally advanced rectal cancer (LARC), initial treatment with neoadjuvant chemoradiotherapy followed by surgery and chemotherapy in selected patients is considered one of the recommended options by the main international clinical guidelines. Nonetheless, the administration of all chemotherapy before definitive treatment (total neoadjuvant therapy or TNT) is an optimal alternative with a growing level of evidence that must be evaluated in multidisciplinary boards. This review summarizes the available data and controversies in this scenario.

SUMMARY

we have analyzed the characteristics of the main published studies that assess the use of TNT in patients with LARC, evaluating their inclusion criteria and distinguishing between the employed radiotherapy fractionations, systemic agents, timing, and the implications of these treatments in regard to surgery and long-term oncological results. Our aim is to describe the evidence that supports the use of a specific regime in everyday clinical practice.

KEY POINTS

there is solid evidence for the use of TNT in patients with LARC. There is no data indicating the superiority of one specific TNT scheme among all the existing options. International clinical guidelines leave the door open to choose the most adequate treatment based on the clinical and pathological characteristics of each patient. This review shows the different approaches to TNT and assesses the best options based on clinical evidence.

Prospective Assessment of Bone Metabolism Biomarkers and Survival in Metastatic Castration-resistant Prostate Cancer Patients Treated with Radium-223: The PRORADIUM Study

BACKGROUND

Radium-223 is an active therapy option for bone metastatic castration-resistant prostate cancer (mCRPC). The lack of adequate biomarkers for patient selection and response assessment are major drawbacks for its use.

OBJECTIVE

To assess the prognostic value of bone metabolism biomarkers (BMBs) in ra-223-treated mCRPC patients.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study of mCRPC patients treated with Ra-223 (PRORADIUM study: NCT02925702) was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The main objective of the study was to evaluate the association between high (≥median) baseline values in at least three bone formation (bone alkaline phosphatase [BAP] and C-terminal type-I collagen propeptide) and bone resorption (N-terminal telopeptide and pyridinoline) biomarkers, and survival. The independent prognostic value of each BMB was also assessed. The association with time to radiographic, clinical, and prostate-specific antigen (PSA) progression; time to skeletal-related events; and PSA response were secondary objectives. Multivariable (MV) Cox-regression models were evaluated.

RESULTS AND LIMITATIONS

A total of 169 patients were included. Of the patients, 70.4% received Ra-223 in second/third line; 144 (85.2%) were Eastern Cooperative Oncology Group 0-1, 126 (74.6%) were in pain, and 80 (47.5%) had more than ten bone metastases. Sixty-seven (39.6%) patients had elevation in at least three BMBs. The median overall survival was 12.1 mo (95% confidence interval [CI]: 10-14.7). No association was observed with other treatment-related secondary outcome parameters. Patients with high values in three or more BMBs had significantly worse survival (9.9 vs 15.2 mo; hazard ratio [HR]: 1.8 [95% CI: 1.3-2.5]; p < 0.001) in the univariate analysis, but not independent in the MV analysis (HR: 1.33; 95% CI: 0.89-2; p = 0.181). High baseline BAP was the only biomarker associated with survival in the MV model (HR: 1.89; 95% CI: 1.28-2.79; p = 0.001). Addition of BAP to the MV clinical model increased the area under the receiver operating characteristic curve 2-yr value from 0.667 to 0.755 (p = 0.003).

CONCLUSIONS

Biomarkers of bone formation, especially BAP, have prognostic value in mCRPC patients treated with radium-223. Its predictive value remains to be assessed, ideally in prospective, adequately powered, randomised clinical trials.

PATIENT SUMMARY

In this study, we evaluate the role of bone metabolism biomarkers to help improve the use of radium-223 as therapy for advanced prostate cancer. We found that bone alkaline phosphatase may be a suitable tool.

Treatment of metastatic squamous cell carcinoma arising in sacrococcygeal pilonidal sinus: a case report series

Background

Squamous cell carcinoma (SCC) arising in a sacrococcygeal pilonidal sinus is rare, with cases of metastatic disease being even rarer. Among published cases, almost none have reported on systemic treatment.

Objective

This disease has a poorer prognosis than other forms of cutaneous SCC; therefore, our objective is to shed some light on the treatment of metastatic disease.

Methods

We present a series of nine cases treated at a single center, four of whom received systemic treatment. Additionally, other previously reported cases of metastatic disease are included in an attempt to draw stronger conclusions.

Results

Four patients were treated under several treatment regimens, with a median progression-free survival of only 2 months and two instances of partial response (18%). The best result was achieved with cemiplimab. Across all the cases, there was a trend toward a benefit of the use of systemic treatment (HR 0.41, 95% CI 0.15-1.12, p = 0.083; median overall survival 13 vs. 8 months).

Limitations

Limitations include the significant lack of information on previously published cases and the extremely heterogeneous nature of the existing information.

Conclusion

The initial systemic treatment should be an anti-PD-1, as with other SCCs. After progression on anti-PD-1, there is no strong evidence to support the recommendation of a specific treatment or sequence: options include cetuximab and/or chemotherapy (platinum, paclitaxel, 5-fluorouracyl).

Utility of CYP2D6 copy number variants as prognostic biomarker in localized anal squamous cell carcinoma

BACKGROUND

Anal squamous cell carcinoma (ASCC) is an infrequent tumor whose treatment has not changed since the 1970s. The aim of this study is the identification of biomarkers allowing personalized treatments and improvement of therapeutic outcomes.

METHODS

Forty-six paraffin tumor samples from ASCC patients were analyzed by whole-exome sequencing. Copy number variants (CNVs) were identified and their relation to disease-free survival (DFS) was studied and validated in an independent retrospective cohort of 101 ASCC patients from the Multidisciplinary Spanish Digestive Cancer Group (GEMCAD). GEMCAD cohort proteomics allowed assessing the biological features of these tumors.

RESULTS

On the discovery cohort, the median age was 61 years old, 50% were males, stages I/II/III: 3 (7%)/16 (35%)/27 (58%), respectively, median DFS was 33 months, and overall survival was 45 months. Twenty-nine genes whose duplication was related to DFS were identified. The most representative was duplications of the CYP2D locus, including CYP2D6, CYP2D7P, and CYP2D8P genes. Patients with CYP2D6 CNV had worse DFS at 5 years than those with two CYP2D6 copies (21% vs. 84%; p < .0002, hazard ratio [HR], 5.8; 95% confidence interval [CI], 2.7-24.9). In the GEMCAD validation cohort, patients with CYP2D6 CNV also had worse DFS at 5 years (56% vs. 87%; p = .02, HR = 3.6; 95% CI, 1.1-5.7). Mitochondria and mitochondrial cell-cycle proteins were overexpressed in patients with CYP2D6 CNV.

CONCLUSIONS

Tumor CYP2D6 CNV identified patients with a significantly worse DFS at 5 years among localized ASCC patients treated with 5-fluorouracil, mitomycin C, and radiotherapy. Proteomics pointed out mitochondria and mitochondrial cell-cycle genes as possible therapeutic targets for these high-risk patients.

PLAIN LANGUAGE SUMMARY

Anal squamous cell carcinoma is an infrequent tumor whose treatment has not been changed since the 1970s. However, disease-free survival in late staged tumors is between 40% and 70%. The presence of an alteration in the number of copies of CYP2D6 gene is a biomarker of worse disease-free survival. The analysis of the proteins in these high-risk patients pointed out mitochondria and mitochondrial cell-cycle genes as possible therapeutic targets. Therefore, the determination of the number of copies of CYP2D6 allows the identification of anal squamous carcinoma patients with a high-risk of relapse that could be redirected to a clinical trial. Additionally, this study may be useful to suggest new treatment strategies to increase current therapy efficacy.

Unravelling oligometastatic disease from the perspective of radiation and medical oncology. Part II: prostate cancer and colorectal cancer

Oligometastatic disease (OMD) defines a status of cancer that is intermediate between localized and widely spread metastatic disease, and can be treated with curative intent. While imaging diagnostic tools have considerably improved in recent years, unidentified micrometastases can still escape from current detection techniques allowing disease to progress. The variety of OMD scenarios are mainly defined by the number of metastases, the biological and molecular tumour profiles, and the timing of the development of metastases. Increasing knowledge has contributed to the earlier and improved detection of OMD, underlining the importance of an early disease control. Based on increasing detection rates of OMD in the current real clinical practice and the lack of standardized evidence-based guidelines to treat this cancer status, a board of experts from the Spanish Societies of Radiation Oncology (SEOR) and Medical Oncology (SEOM) organized a series of sessions to update the current state-of-the-art on OMD from a multidisciplinary perspective, and to discuss how results from clinical studies may translate into promising treatment options. This experts' review series summarizes what is known and what it is pending clarification in the context of OMD in the scenarios of Non-Small Cell Lung Cancer and Breast Cancer (Part I), and Prostate Cancer and Colorectal Cancer (Part II), aiming to offer specialists a pragmatic framework that might contribute to the improved management of patients.

Unravelling oligometastatic disease from the perspective of radiation and medical oncology. Part I: non-small cell lung cancer and breast cancer

Oligometastatic disease (OMD) defines a cancer status that is intermediate between localized and widely spread metastatic disease, and can be treated with curative intent. While diagnostic imaging tools have considerably improved in recent years, unidentified micrometastases can still evade current detection techniques, allowing the disease to progress. The various OMD scenarios are mainly defined by the number of metastases, the biological and molecular tumour profiles, and the timing of the development of metastases. Increasing knowledge has contributed to the earlier and improved detection of OMD, underlining the importance of early disease control. In view of increasing OMD detection rates in current real-world clinical practice and the lack of standardized evidence-based guidelines to treat this cancer status, a board of experts from the Spanish Societies of Radiation Oncology (SEOR) and Medical Oncology (SEOM) organized a series of sessions to update the current state-of-the-art on OMD from a multidisciplinary perspective, and to discuss how results from clinical studies might translate into promising treatment options. This expert review series summarizes what is known and what it is pending clarification in the context of OMD in the scenarios of non-small cell lung cancer and breast cancer (Part I), and prostate cancer and colorectal cancer (Part II), aiming to offer specialists a pragmatic framework to help improve patient management.

A phase 2 randomized open-label study of oral darolutamide monotherapy vs. androgen deprivation therapy in men with hormone-naive prostate cancer (EORTC-GUCG 1532)

160

Background: Darolutamide is androgen-receptor (AR) inhibitor with low blood–brain barrier penetration and limited potential for clinically relevant drug–drug interactions. Darolutamide has been shown to increase overall survival in combination with androgen deprivation therapy (ADT) in patients with newly diagnosed metastatic hormone sensitive prostate cancer (PC) and, in combination with docetaxel, in men with non-metastatic castration resistant PC. This phase 2 study assessed the efficacy and safety of DARO as a monotherapy without ADT in patients with non-castrate testosterone (T) levels (≥230 ng/dL). Methods: This was a 24-wk, open-label, randomized study of patients with hormone-naïve, histologically confirmed prostate cancer (all stages, with a max of 4 metastatic lesions) requiring hormonal treatment, an ECOG PS score of 0, and a life expectancy >1 y. All patients received DARO 600 mg bid or commercially available LHRH analogue. The primary endpoint is PSA response defined as a ≥ 80% decline at week 24 relative to baseline, in the DARO study arm. The ADT arm is used as an internal control. Secondary endpoints included changes in T levels, safety/tolerability, and quality of life. Results: Among 61 men enrolled, the median (range) age was 72 y (53-86y); 49.2% had metastases; 14.8% and 62.3% had undergone prostatectomy or radiotherapy before study entry. The median (range) of PSA at baseline was 8.9 ng/mL (2.2-333.8). In the DARO arm, the evaluable population with available PSA values at baseline and week 24 consisted of 21 patients. The PSA response rate (>80% PSA decline at wk 24) was 100%, with a median (range) decrease of -99.6% (-94.3, -100) at wk 24 in the DARO arm. Serum T levels increased by a median (range) of 43.4% (5.7-144.0) at wk 24, compared with baseline. In the DARO arm, 45.2% of men reported drug-related AEs (mostly Grade 1 or 2). Most frequent treatment-emergent AEs included gynaecomastia (19.4%), fatigue (12.9%), and hot flush (12.9%). 3.1% of men experienced SAEs, none of which were drug related. HR-QoL measures and ADT arm results will be presented as internal reference. Conclusions: DARO monotherapy (600 mg bid) was associated with significant PSA response in nearly all men with hormone-naïve prostate cancer. Testosterone level changes and most common AEs (gynecomastica, fatigue and hot flush) were consistent with potent AR inhibition. Clinical trial information: NCT02972060 .

Stereotactic body radiation therapy for kidney cancer. Where do we stand?

At present, surgery is still the gold standard for the local treatment of renal cancer. Nonetheless, in several clinical scenarios, stereotactic body radiation therapy (SBRT) also known as stereotactic ablative body radiotherapy (SABR) is emerging as a highly effective ablative technique in fragile patients and those with significant comorbidities, as well as in cases where percutaneous therapy (cryoablation or radiofrequency) is not viable. However, considering the intrinsic radioresistance of renal tumors, the optimal treatment schemes have not been established. In oligometastatic patients, it has been reported that the control of the oligometastases can be a potentially curable approach. Being a technique than can be administered exclusively or in combination with systemic therapy, treatment individualization based on patient characteristics is key. Another scenario under investigation is oligoprogression, where SBRT offers the possibility of delaying further lines of systemic therapy by eliminating subclones of resistant tumor with ablative doses, with the additional opportunity of stimulating the immune system (immunomodulatory role). In this review, we have conducted an analysis of recently published studies that test the role of this technique in different clinical scenarios of this disease. We have found promising results that make SBRT a potent therapeutic approach with low toxicity. We also comment on ongoing studies that will generate the necessary evidence needed for the implementation of this technique in our daily clinical practice.

Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio as prognostic factors in locally advanced rectal cancer

INTRODUCTION The standard therapy for locally advanced rectal cancer is based on neoadjuvant chemoradiotherapy (nCRT) with fluoropyrimidines. There are different biomarkers used as prognostic factors in these tumors. Some studies advocate the use of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as prognostic factors in this clinical scenario. The aim of the study is to evaluate NLR and PLR as prognostic factors of disease-free survival (DFS) and overall survival (OS) and as predictive factors of pathological complete response (pCR) using Ryan tumor regression scoring system on surgical specimens, in patients with locally advanced rectal adenocarcinoma who received nCRT and radical surgery. METHODS We retrospectively evaluated patients with locally advanced rectal adenocarcinoma (T3-T4, N1-N3, M0 according to the TNM classification, AJCC 8th edition) who received neoadjuvant chemoradiotherapy based on fluoropyrimidines and radical surgery. Complete blood cell count before nCRT were obtained to calculate NLR and PLR. We made subgroups of patients according to NLR and PLR. We obtained the cut-off point for these ratios based on receiver operating characteristic analysis. We analyzed OS and DFS using the Kaplan-Meier method and Cox proportional hazard models. The relationships between NLR/PLR and pCR, along with other clinical-pathological characteristics were evaluated by Pearson´s χ2 or Fisher´s exact test as appropriate. Multivariate analyses were performed using Cox proportional hazard regression models. RESULTS Between February 2012 and February 2017, 100 consecutive patients were treated according to the reported schedules. Median age was 76 years (68-83). All patients received radiotherapy up to 50,4 Gy and 5-FU-based chemotherapy. 100% completed nCRT and surgery. 38% had elevated basal NLR (cut-off >1,95), 50% had elevated basal PLR (cut-off >133). After a median follow-up of 72 months (55-88), a lower DFS was obtained in the high NLR subgroup (Long Rank, Mantel-Cox 5,165, p=0,023) and in the high PLR subgroup (Long Rank, Mantel-Cox 13,971, p=0,001). Multivariate analysis showed that PLR (p=0,006) was a strong significant predictor of DFS. A lower overall survival was observed in the high NLR and PLR subgroup without significant differences (Long Rank, Mantel-Cox 1,245, p= 0,265; 0,578, p=0,447). No significant differences were obtained in any of the subgroups analysis regarding pCR rates. CONCLUSION In light of our results, both NLR and PLR could be considered prognostic factors for DFS in patients with LARC that receive treatment with nCRT followed by surgery.

SARS-CoV-2 Virus in Cancer Patients: A New Unknown in an Unsolved Equation

INTRODUCTION

Cancer patients are more susceptible to infections, and infection can be more severe than in patients without cancer diagnosis. We conducted this retrospective study in patients admitted for SARS-CoV-2 infection in order to find differences in inflammatory markers and mortality in cancer patients compared to others.

METHODS

We reviewed the electronic records of patients admitted for SARS-CoV-2 infection confirmed by PCR from March to September 2020. Data on socio-demographics, comorbidities, inflammatory makers, and cancer-related features were analyzed.

RESULTS

2,772 patients were admitted for SARS-CoV-2, to the Hospital Universitario Ramón y Cajal in Madrid during this period. Of these, 2,527 (91%) had no history of neoplastic disease, 164 (5.9%) patients had a prior history of cancer but were not undergoing oncological treatment at the time of infection, and 81 (2.9%) were in active treatment. Mortality in patients without a history of cancer was 19.5%, 28.6% for patients with a prior history of cancer, and 34% in patients with active cancer treatment. Patients in active oncology treatment with the highest mortality rate were those diagnosed with lung cancer (OR 5.6 95% CI: 2.2-14.1). In the multivariate study, active oncological treatment (OR 2.259 95% CI: 1.35-3.77) and chemotherapy treatment (OR 3.624 95% CI: 1.17-11.17), were statistically significant factors for the risk of death for the whole group and for the group with active oncological treatment, respectively.

CONCLUSION

Cancer patients on active systemic treatment have an increased risk of mortality after SARS-CoV-2 infection, especially with lung cancer or chemotherapy treatment.

Assessing radiation dose for postoperative radiotherapy in prostate cancer: Real world data

BACKGROUND

Approximately 30% of patients with localized prostate cancer (PCa) who undergo radical prostatectomy will develop biochemical recurrence. In these patients, the only potentially curative treatment is postoperative radiotherapy (PORT) with or without hormone therapy. However, the optimal radiotherapy dose is unknown due to the limited data available.

AIM

To determine whether the postoperative radiotherapy dose influences biochemical failure-free survival (BFFS) in patients with PCa.

METHODS

Retrospective analysis of patients who underwent radical prostatectomy for PCa followed by PORT-either adjuvant radiotherapy (ART) or salvage radiotherapy (SRT)-between April 2002 and July 2015. From 2002 to 2010, the prescribed radiation dose to the surgical bed was 66-70 Gy in fractions of 2 Gy; from 2010 until July 2015, the prescribed dose was 70-72 Gy. Patients were grouped into three categories according to the total dose administered: 66-68 Gy, 70 Gy, and 72 Gy. The primary endpoint was BFFS, defined as the post-radiotherapy prostate-specific antigen (PSA) nadir + 0.2 ng/mL. Secondary endpoints were overall survival (OS), cancer-specific survival (CSS), and metastasis-free survival (MFS; based on conventional imaging tests). Treatment-related genitourinary (GU) and gastrointestinal (GI) toxicity was evaluated according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. Finally, we aimed to identify potential prognostic factors. BFFS, OS, CSS, and MFS were calculated with the Kaplan-Meier method and the log-rank test. Univariate and multivariate Cox regression models were performed to explore between-group differences in survival outcome measures.

RESULTS

A total of 301 consecutive patients were included. Of these, 93 (33.6%) received ART and 186 (66.4%) SRT; 22 patients were excluded due to residual macroscopic disease or local recurrence in the surgical bed. In this subgroup (n = 93), 43 patients (46.2%) were Gleason score (GS) ≤ 6, 44 (47.3%) GS 7, and 6 (6.5%) GS ≥ 8; clinical stage was cT1 in 51 (54.8%), cT2 in 35 (39.3%), and cT3 in one patient (1.1%); PSA was < 10 ng/mL in 58 (63%) patients, 10-20 ng/mL in 28 (30.6%), and ≥ 20 ng/mL in 6 (6.4%) patients. No differences were found in BFFS in this patient subset versus the entire cohort of patients (P = 0.66). At a median follow-up of 113 months (range, 4-233), 5- and 10-year BFFS rates were 78.8% and 73.7%, respectively, with OS rates of 93.3% and 81.4%. The 5-year BFFS rates in three groups were as follows: 69.6% (66-68 Gy), 80.5% (70 Gy) and 82.6% (72 Gy) (P = 0.12):the corresponding 10-year rates were 63.9%, 72.9%, and 82.6% (P = 0.12), respectively. No significant between-group differences were observed in MFS, CSS, or OS. On the univariate analysis, the following variables were significantly associated with BFFS: PSA at diagnosis; clinical stage (cT1 vs cT2); GS at diagnosis; treatment indication (ART vs SRT); pre-RT PSA levels; and RT dose 66 -68 Gy vs. 72 Gy (HR: 2.05; 95%CI: 1.02-4.02, P = 0.04). On the multivariate analysis, the following variables remained significant: biopsy GS (HR: 2.85; 95%CI: 1.83-4.43, P < 0.001); clinical stage (HR: 2.31; 95%CI: 1.47-4.43, P = 0.01); and treatment indication (HR: 4.11; 95%CI: 2.06-8.17, P < 0.001). Acute grade (G) 1 GU toxicity was observed in 11 (20.4%), 17 (19.8%), and 3 (8.3%) patients in each group (66-68 Gy, 70 Gy and 72 Gy), respectively (P = 0.295). Acute G2 toxicity was observed in 2 (3.7%), 4 (4.7%) and 2 (5.6%) patients, respectively (P = 0.949). Acute G1 GI toxicity was observed in 16 (29.6%), 23 (26.7%) and 2 (5.6%) patients in each group, respectively (P = 0.011). Acute G2 GI toxicity was observed in 2 (3.7%), 6 (6.9%) and 1 (2.8%) patients, respectively (P = 0.278). No cases of acute G3 GI toxicity were observed.

CONCLUSION

The findings of this retrospective study suggest that postoperative radiotherapy dose intensification in PCa is not superior to conventional radiotherapy treatment.

Immunotherapy in Advanced Prostate Cancer: Current Knowledge and Future Directions

The advent of immunotherapy has revolutionized cancer treatment. Unfortunately, this has not been the case for metastatic castration-resistant prostate cancer (mCRPC), likely due to the heterogeneous and immune-suppressive microenvironment present in prostate cancer. The identification of molecular biomarkers that could predict response to immunotherapy represents one of the current challenges in this clinical scenario. The management of advanced castration-resistant prostate cancer is rapidly evolving and immunotherapy treatments, mostly consisting of immune checkpoint inhibitors combinations, BiTE® (bispecific T-cell engager) immune therapies, and chimeric antigen receptors (CAR) are in development with promising results. This review analyses the current evidence of immunotherapy treatments for mCRPC, evaluating past failures and promising approaches and discussing the directions for future research.

Bone health and therapeutic agents in advanced prostate cancer

Prostate cancer is the most frequent genitourinary tumor worldwide. Maintaining an optimum bone health throughout the natural course of prostate cancer is an important aspect in the management of this disease, particularly in this at risk population of older and frail patients who experience bone loss related to androgen-deprivation therapy (ADT) and/or patients who develop bone metastases. The number of treatment options for advanced prostate cancer that combine ADT with docetaxel, new hormonal agents and/or radiotherapy has increased substantially in recent years. Bisphosphonates and other bone targeted agents such as denosumab have shown an improvement in bone mineral density and are suited for patients with treatment-related osteoporosis and/or bone metastases with an increased risk of skeletal-related events (SREs). In this context, the aim of this review is to analyse key aspects of bone health and therapies that can prevent the occurrence of SREs throughout the clinical course of prostate cancer, and how to combine them with new available treatments in this setting.

Treatment Landscape of Nonmetastatic Castration-Resistant Prostate Cancer: A Window of Opportunity

The treatment for nonmetastatic castration-resistant prostate cancer (nmCRPC) is a highly unmet medical need. The classic treatment approach for these patients-androgen deprivation therapy (ADT) alone-until metastatic progression is now considered suboptimal. Several randomized phase III clinical trials have demonstrated significant clinical benefits-including significantly better overall survival (OS)-for treatments that combine ADT with apalutamide, enzalutamide, and darolutamide. As a result, these approaches are now included in treatment guidelines and are considered a standard of care. In the present article, we discuss the changing landscape of the management of patients with nmCRPC.

Evaluation of PSA progression after initiation of enzalutamide or abiraterone: Real-world data on metastatic castration-resistant prostate cancer (mCRPC)

5024

Background: PSA value is widely used for the monitoring of treatment outcome in mCRPC in the clinical real-world setting. Early PSA changes are not considered in the definition of PSAProg due to the potential for spurious “flare” reactions. We aimed to evaluate the significance of an early PSA increase in mCRPC patients (pts) treated with enzalutamide or abiraterone (Enz/Abi). Methods: We retrospectively evaluated Enz/Abi-treated mCRPC pts from 11 hospitals between 2011-2020. Early PSAProg was defined as a 25% increase in PSA from baseline at 4 (PSAProg4) or 8 (PSAProg8) weeks after treatment initiation. PSA progression at 12 weeks (PSAProg12) was confirmed by a second reading. Uni- and multivariable (MV) Cox regression models were conducted to explore the association of PSAProg and overall survival (OS) in chemotherapy naïve patients treated with Abi or Enz. Interaction tests were conducted to explore differences in the impact of PSA progression on OS in Abi or Enz-treated pts. Results: We analyzed 511 chemotherapy-naïve mCRPC pts treated with Abi (N=391; 76.5%) or Enz (N=120; 23.5%). Median follow-up: 30.2 months. OS was longer in Enz-treated pts (38.1 vs 29m; HR 1.4; p=0.027). 59 (15.1%), 70 (17.9%) and 48 (12.3%) of Abi-treated and 9 (7.5%), 11 (9.2%) and 10 (8.3%) of Enz-treated pts experienced PSAProg4, PSAProg8 and PSAProg12, respectively, although differences were not statistically significant. PSAProg was associated with worse OS at all 3 timepoints only in Abi-treated pts. In Enz-treated pts, PSAProg4 had a large impact on OS, not observed in PSAProg8 or PSAProg12. We observed no significant interaction between agent (Enz/Abi) and PSA progression (Table). Conclusions: PSA progression at 4 weeks after Enz/Abi is significantly associated with shorter OS and may help identify pts not benefitting from Abi/Enz before clinical or radiographic progression. PSA pattern progression and its association with OS might differ depending on the drug used (Enz/Abi). Prospective validation studies are needed.[Table: see text]

Current role of nanoparticles in the treatment of lung cancer

BACKGROUND

Worldwide, lung cancer is one of the leading causes of cancer death. Nevertheless, new therapeutic agents have been developed to treat lung cancer that could change this mortality-rate. Interestingly, incredible advances have occurred in recent years in the development and application of nanotechnology in the detection, diagnosis, and treatment of lung cancer.

AIM

Nanoparticles (NPs) have the ability to incorporate multiple drugs and targeting agents and therefore lead to an improved bioavailability, sustained delivery, solubility, and intestinal absorption.

RELEVANCE FOR PATIENTS

This review briefly summarizes the latest innovations in therapeutic nanomedicine in lung cancer with examples on magnetic, lipid, and polymer NP. Emphasis will be placed on future studies and ongoing clinical trials in this field.

SEOR SBRT-SG survey on SRS/SBRT dose prescription criteria in Spain

AIM

Stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS) are essential tools in radiation oncology. In Spain, the use of these techniques continues to grow as older linear accelerators (linacs) are replaced with modern equipment. However, little is known about inter-centre variability in prescription and dose heterogeneity limits. Consequently, the SBRT-Spanish Task Group (SBRT-SG) of the Spanish Society of Radiation Oncology (SEOR) has undertaken an initiative to assess prescription and homogeneity in SRS/SBRT treatment. In the present study, we surveyed radiation oncology (RO) departments to obtain a realistic overview of prescription methods used for SBRT and SRS treatment in Spain.

METHODS

A brief survey was developed and sent to 34 RO departments in Spain, mostly those who are members of the SEOR SBRT-SG. The survey contained seven questions about the specific prescription mode, dose distribution heterogeneity limits, prescription strategies according to SRS/SBRT type, and the use of IMRT-VMAT (Intensity Modulated Radiation Therapy-Volumetric Modulated Arc Therapy).

RESULTS

Responses were received from 29 centres. Most centres (59%) used the prescription criteria D_95% ≥ 100%. Accepted dose heterogeneity was wide, ranging from 107 to 200%. Most centres used IMRT-VMAT (93%).

CONCLUSIONS

This survey about SRS/SBRT prescription and dose heterogeneity has evidenced substantial inter-centre variability in prescription criteria, particularly for intended and accepted dose heterogeneity. These differences could potentially influence the mean planning target volume dose and its correlation with treatment outcomes. The findings presented here will be used by the SEOR SBRT-SG to develop recommendations for SRS/SBRT dose prescription and heterogeneity.

Metastatic hormone-sensitive prostate cancer: How should it be treated?

The number of treatment options for metastatic hormone-sensitive prostate cancer has increased substantially in recent years. The classic treatment approach for these patients—androgen-deprivation therapy alone—is now considered suboptimal. Several randomized phase III clinical trials have demonstrated significant clinical benefits—including significantly better overall survival and quality of life—for treatments that combine androgen-deprivation therapy with docetaxel, abiraterone acetate, enzalutamide, apalutamide, and/or radiotherapy to the primary tumour. As a result, these approaches are now included in treatment guidelines and considered standard of care. However, the different treatment strategies have not been directly compared, and thus treatment selection remains at the discretion of the individual physician or, ideally, a multidisciplinary team. Given the range of available treatment approaches with varying toxicity profiles, treatment selection should be individualized based on the patient’s clinical characteristics and preferences, which implies active patient participation in the decision-making process. In the present document, we discuss the changing landscape of the management of patients with metastatic hormone-sensitive prostate cancer in the context of several recently-published landmark randomized trials. In addition, we discuss several unresolved issues, including the optimal sequencing of systemic treatments and the incorporation of local treatment of the primary tumour and metastases.

Association between BRCA2 alterations and intraductal and cribriform histologies in prostate cancer

BACKGROUND

Intraductal (IDC) and cribriform (CRIB) histologies in prostate cancer have been associated with germline BRCA2 (gBRCA2) mutations in small retrospective series, leading to the recommendation of genetic testing for patients with IDC in the primary tumour.

PATIENTS AND METHODS

To examine the association of gBRCA2 mutations and other tumour molecular features with IDC and/or cribriform (CRIB) histologies, we conducted a case-control study in which primary prostate tumours from 58 gBRCA2 carriers were matched (1:2) by Gleason Grade Group and specimen type to 116 non-carriers. Presence/absence of IDC and CRIB morphologies was established by two expert uropathologists blinded to gBRCA2 status. Fluorescent in-situ hybridization (FISH) and next-generation sequencing (NGS) were used to detect BRCA2 alterations, PTEN deletions and TMPRSS2-ERG fusions. Chi-squared tests were used to compare the frequency of IDC and CRIB in gBRCA2 carriers and controls and to assess associations with other variables. Logistic regression models were constructed to identify independent factors associated with both histology patterns.

RESULTS

No significant differences between gBRCA2 carriers and non-carriers were observed in the prevalence of IDC (36% gBRCA2 versus 50% non-carriers, p = 0.085) or CRIB (53% gBRCA2 versus 43% non-carriers p = 0.197) patterns. However, IDC histology was independently associated with bi-allelic BRCA2 alterations (OR 4.3, 95%CI 1.1-16.2) and PTEN homozygous loss (OR 5.2, 95%CI 2.1-13.1). CRIB morphology was also independently associated with bi-allelic BRCA2 alterations (OR 5.6, 95%CI 1.7-19.3).

CONCLUSIONS

While we found no association between gBRCA2 mutations and IDC or CRIB histologies, bi-allelic BRCA2 loss in primary prostate tumours was significantly associated with both variant morphologies, independently of other clinical-pathologic factors.

Recommended procedures and responsibilities for radiosurgery (SRS) and extracranial stereotactic body radiotherapy (SBRT): report of the SEOR in collaboration with the SEFM

Today, patient management generally requires a multidisciplinary approach. However, due to the growing knowledge base and increasing complexity of Medicine, clinical practice has become even more specialised. Radiation oncology is not immune to this trend towards subspecialisation, which is particularly evident in ablative radiotherapy techniques that require high dose fractions, such as stereotactic radiosurgery (SRS), and stereotactic body radiotherapy (SBRT). The aim of the present report is to establish the position of the Spanish Society of Radiation Oncology (SEOR), in collaboration with the Spanish Society of Medical Physics (SEFM), with regard to the roles and responsibilities of healthcare professionals involved in performing SRS and SBRT. The need for this white paper is motivated due to the recent changes in Spanish Legislation (Royal Decree [RD] 601/2019, October 18, 2019) governing the use and optimization of radiotherapy and radiological protection for medical exposure to ionizing radiation (article 11, points 4 and 5) [1 ], which states: "In radiotherapy treatment units, the specialist in Radiation Oncology will be responsible for determining the correct treatment indication, selecting target volumes, determining the clinical radiation parameters for each volume, directing and supervising treatment, preparing the final clinical report, reporting treatment outcomes, and monitoring the patient's clinical course." Consequently, the SEOR and SEFM have jointly prepared the present document to establish the roles and responsibilities for the specialists-radiation oncologists (RO), medical physicists (MP), and related staff -involved in treatments with ionizing radiation. We believe that it is important to clearly establish the responsibilities of each professional group and to clearly establish the professional competencies at each stage of the radiotherapy process.

Genetic testing for the clinician in prostate cancer

INTRODUCTION

Prostate cancer (PCa) is one of the most common cancers worldwide and a leading cause of cancer-related mortality. Although the diagnosis and treatment of prostate cancer has improved substantially in recent years, new molecular biomarkers are needed to further prolong survival and improve the quality of life in these patients.

AREAS COVERED

This review analyzes the current evidence for prognostic and predictive molecular biomarkers that can be applied across different clinical scenarios, ranging from localized disease to metastatic castration-resistant PCa, with a particular emphasis on the biomarkers likely to become available in routine clinical practice in the near future.

EXPERT OPINION

There is a growing need for molecular testing to identify the most indolent types of prostate cancer to help optimize treatment strategies and spare treatment in these patients when possible. Current trends in the treatment of prostate cancer underscore the unmet clinical need for biomarkers to improve decision-making in a challenging clinical setting.

Watch and wait approach in rectal cancer: Current controversies and future directions

According to the main international clinical guidelines, the recommended treatment for locally-advanced rectal cancer is neoadjuvant chemoradiotherapy followed by surgery. However, doubts have been raised about the appropriate definition of clinical complete response (cCR) after neoadjuvant therapy and the role of surgery in patients who achieve a cCR. Surgical resection is associated with significant morbidity and decreased quality of life (QoL), which is especially relevant given the favourable prognosis in this patient subset. Accordingly, there has been a growing interest in alternative approaches with less morbidity, including the organ-preserving watch and wait strategy, in which surgery is omitted in patients who have achieved a cCR. These patients are managed with a specific follow-up protocol to ensure adequate cancer control, including the early identification of recurrent disease. However, there are several open questions about this strategy, including patient selection, the clinical and radiological criteria to accurately determine cCR, the duration of neoadjuvant treatment, the role of dose intensification (chemotherapy and/or radiotherapy), optimal follow-up protocols, and the future perspectives of this approach. In the present review, we summarize the available evidence on the watch and wait strategy in this clinical scenario, including ongoing clinical trials, QoL in these patients, and the controversies surrounding this treatment approach.

Clinical Applications of Molecular Biomarkers in Prostate Cancer

There is clinically relevant molecular heterogeneity in prostate cancer (PCa), but this biological diversity has had only a minimal impact on clinical practice. Treatment outcomes in patients with localised PCa are often highly variable, even among patients stratified to the same risk group or disease state based on standard clinical and pathological parameters. In recent years, the development of gene panels has provided valuable data on the differential expression of genes in patients with PCa. Nevertheless, there is an urgent need to identify and validate prognostic and predictive biomarkers that can be applied across clinical scenarios, ranging from localised disease to metastatic castration-resistant PCa. The availability of such tools would allow for precision medicine to finally reach PCa patients. In this review, we evaluate current data on molecular biomarkers for PCa, with an emphasis on the biomarkers and gene panels with the most robust evidence to support their application in routine clinical practice.

PROREPAIR-A: Clinical and molecular characterization study of prostate cancer (PC) patients with and without previously known germline BRCA1/2 mutations

5511

Background: Germline BRCA1/2 (g BRCA1/2) mutations are associated with poor clinical outcomes in PC. Previous studies showed that g BRCA2 carriers present more CNV in several genes associated with more aggressive disease. These aberrations may explain the poor clinical outcomes of these patients, but larger studies are needed to confirm these findings. Methods: PROREPAIR-A is a multicenter case-control study in which g BRCA2 carriers with available diagnostic timor-tissue were matched 1:2 by Gleason and stage at diagnosis (M0 vs M1) with known non-carriers (NC). A minimum of 120 controls-60 cases were required to prove a 5yr Cause Specific Survival (CSS)-rate of 85% vs 60%. The primary endpoint was to confirm the independent prognostic value of g BRCA2 in PC CSS. In addition, we explored the prognostic role of g BRCA1 and somatic events in BRCA2, RB1, MYC, PTEN and TMPRSS2-ERG by FISH. Χ2, Kaplan-Meier, log-rank and cox-regression models were carried out to identify associations with baseline characteristics and outcomes: Metastases Free Survival (MFS), Time to Castration-Resistance (TTCR) and CSS. Results: A total of 80:160 matched cases-controls were initially included, but tumor tissue and clinical data were only available in 73 g BRCA2 and 127 NC. 14 g BRCA1 were also included. At diagnosis, g BRCA2 were younger (median 62.6 vs 64.5, p = 0.02) and had cT3-4 disease more often than NC (31.5% vs 9.4%, p < 0.01), but no other significant differences were found. Somatic BRCA2-RB1 codeletion (40.8% vs 11.8%, p < 0.01) and MYC amplification (51.4% vs 22.8%, p < 0.01) were more frequent in g BRCA2 compared to NC, but no significant differences in PTEN and TMPRSS2-ERG were observed. g BRCA2 mutations as well as somatic BRCA2-RB1 codel and MYC amplif were significantly associated with shorter CSS, MFS and TTCR (Table). MVA model confirmed the independent prognostic value of g BRCA2 (HR 1.94, p = 0.03), BRCA2-RB1 codel (HR 3.16, p < 0.01), MYC amplif (HR 2.36, p < 0.01), Gleason ≥8 (p < 0.01) and M1 at diagnosis (p < 0.01) for CSS. Conclusions: PROREPAIR-A confirmed the independent prognostic value of g BRCA2 for CSS. Somatic BRCA2, RB1 and MYC aberrations were more frequent in g BRCA2 carriers. Those alterations are associated with shorter CSS, MFS and TTCR, and may contribute to poor clinical outcomes in g BRCA2 and NC. [Table: see text]

Metformin and statins: a possible role in high-risk prostate cancer

Aim and background

There is increasing evidence that statins and oral anti-diabetic drugs, such as metformin, can have a favorable role in advanced prostate cancer treatment.Metformin has been shown to inhibit proliferation of tumor cells in vitro and statins inhibit carcinogenesis by suppressing angiogenesis/invasion mechanisms. However, clinical evidence on the protective effect of these drugs is still weak.The purpose of this study is to analyze if these drugs have an impact on Biochemical-Failure-Free-Survival (BFFS) and on Distant-Failure-Free-Survival (DFFS) in localized high-risk prostate cancer.

Material and Methods

From 2002-2016, 447 patients with histologically confirmed high-risk prostate cancer were retrospectively evaluated. All patients received radiotherapy and androgen deprivation therapy. Biochemical recurrence was determined by the Phoenix criteria and metastatic patients were defined by the presence of radiological metastasis. Survival analysis was performed using the Kaplan-Meier method.

Results

175 patients were treated with statins (65.3 % with a dose ≤ 20 mg/day) and 70 with metformin (75.7 % with a dose ≤ 1700 mg/day). Median follow-up was 88 months (1-194) with no differences in BFFS and DFFS between metformin and non-metformin patients (77.4 % versus 80 %, p = 0.91 and 89.4 % versus 88.7 %, p = 0.56, respectively). We did not find a statistical difference in BFFS and DFFS in patients taking higher doses of those drugs.

Conclusion

Metformin and statins were not associated with BFFS or DFFS improvement in our analysis. However, the small number of patients treated with these drugs limits the reliability of the results and prospective studies are needed.

Early PSA progression in abiraterone/enzalutamide-treated patients with metastatic castration-resistant prostate cancer

e16530

Background: Changes in PSA are widely used as a biomarker for the monitoring of treatment outcome in Metastatic Castration-Resistant Prostate Cancer (mCRPC) in the clinical real-world setting. Early PSA changes (before 12 weeks) are not considered in the definition of PSA Progression (PSAProg) due to the potential for spurious “flare” reactions. We aimed to evaluate the significance of an early PSA increase in Abiraterone/Enzalutamide (Abi/Enz)-treated mCRPC patients (pts). Methods: We retrospectively evaluated Abi/Enz-treated mCRPC pts from 11 hospitals between 2011-2018. Early PSAProg was defined as a 25% increase in PSA from baseline at 4 (PSAProg4) or 8 (PSAProg8) weeks after treatment initiation. PSA progression at 12 weeks (PSAProg12) was confirmed by a second reading. Uni- and multivariable (MV) Cox regression models were conducted to explore the association of PSAProg and overall (OS) and radiographic progression-free (rPFS) survival. Sensitivity (Se), specificity (Sp) and predictive values (PPV, NPV) for the association of early PSAProg with PSAProg12 were calculated. Results: We analyzed 581 mCRPC pts; median follow-up: 19.1 months. 96 (17.1%); 105 (21.6%) and 85 (16.9%) pts had PSAprog at 4, 8 and 12 wks. PSAProg4 and PSAProg8 were significantly associated with confirmed PSAProg12. 55.3% of pts with PSAProg4 and 66.7% of pts with PSAProg8 had a confirmed PSAProg12. Only 9% of pts with no PSA prog at 4 wks and 4.1% of pts with no PSAProg8 had a confirmed PSAProg12. PSAProg4 had Se: 56.6%, Sp: 90.5%, PPV: 55.2%, NPV: 91% for the detection of PSAProg12. PSAProg8 had Se: 81.9%, Sp: 91.2%, PPV: 66.7%, NPV: 95.9% for the detection of PSAProg12. PSAprog at 4, 8 and 12 wks was significantly associated with OS and rPFS in uni- and MV Cox models (Table). Conclusions: Early PSAProg after Abi/Enz is significantly associated with both confirmed PSA Prog at 12 wks and outcome, and may help identify pts not benefitting from Abi/Enz before clinical or radiographic progression. Prospective validation studies are needed. [Table: see text]

Correlation between time to PSA progression (TTPP), radiographic progression-free survival (rPFS) and overall survival (OS) in first-line abiraterone/enzalutamide (Abi/Enza) and docetaxel (Doc) treated patients in a prospective cohort study

267

Background: Abiraterone, enzalutamide and docetaxel represent first-line (1L) treatment options in mCRPC. A significant correlation between rPFS and OS has been reported for patients treated with 1L abi and enza in mCRPC. It is however unclear whether TTPP or rPFS present a similar magnitude of correlation with OS in Doc-treated pts. Methods: We evaluated the association of TTPP and rPFS with OS in pts treated with 1L Abi/Enza or Doc in a prospective multicenter observational cohort study. TTPP and rPFS were defined as per PCWG2. Correlation between TTPP and rPFS with OS was evaluated with Spearman rho coefficients (r), and by calculating the concordance index (c-index) in Cox-regression models. Results: 406 out of 419 pts received 1L Abi/Enza or Doc. After a median follow-up of 40 months (m), 253 mCRPC-related deaths were observed, with a median OS of 31.3 m (95% CI: 27.6-35). Median rPFS and TTPP were 10.8 m (95% CI:9.7-11.9) and 7.2 m (95% CI:6.7-7.7), respectively. Significant correlations between rPFS/TTPP and OS were observed in all pts treated at 1L, as well as in Abi/Enza and Doc treated pts (Table). R and c-index were consistently higher in Abi/Enza treated pts than in Doc treated pts, with a higher difference in predictive accuracy of the Cox regression model observed when comparing the association between TTPP and OS (c-index 0.788 in Abi/Enza treated pts vs 0.627 in Doc treated pts). Conclusions: Differences in r and c-index were observed when evaluating the association between TTPP/rPFS and OS in Abi/Enza and Doc treated pts, suggesting rPFS and TTPP may better predict OS in Abi/Enza than in Doc-treated pts. Indirect comparisons of TTPP in Abi/Enza vs Doc pts may therefore not reflect their true impact on OS. Further insight on the exact significance of TTPP is needed. Clinical trial information: NCT03075735. [Table: see text]

Time for radioimmunotherapy: an overview to bring improvements in clinical practice

Harnessing the patient's own immune system against an established cancer has proven to be a successful strategy. Within the last years, several antibodies blocking critical "checkpoints" that control the activation of T cells, the immune cells able to kill cancer cells, have been approved for the use in patients with different tumours. Unfortunately, these cases remain a minority. Over the last years, radiotherapy has been reported as a means to turn a patient's own tumour into an in situ vaccine and generate anti-tumour T cells in patients who lack sufficient anti-tumour immunity. Indeed, review data show that the strategy of blocking multiple selected immune inhibitory targets in combination with radiotherapy has the potential to unleash powerful anti-tumour responses and improve the outcome of metastatic solid tumours. Here, we review the principal tumours where research in this field has led to new knowledge and where radioimmunotherapy becomes a reality.

Phase II pilot study of the prednisone to dexamethasone switch in metastatic castration-resistant prostate cancer (mCRPC) patients with limited progression on abiraterone plus prednisone (SWITCH study)

BACKGROUND

Despite most metastatic castration-resistant prostate cancer (mCRPC) patients benefit from abiraterone acetate plus prednisone 5 mg bid (AA + P), resistance eventually occurs. Long-term use of prednisone has been suggested as one of the mechanisms driving resistance, which may be reversed by switching to another steroid.

METHODS

SWITCH was a single-arm, open-label, single-stage phase II study. The primary objective was to evaluate the antitumour activity of abiraterone acetate plus dexamethasone 0.5 mg daily (AA + D) in mCRPC patients progressing to AA + P. Clinically stable mCRPC patients who had prostate-specific antigen (PSA) and/or limited radiographic progression after at least 12 weeks on AA + P, were eligible. The primary endpoint was measured as the proportion of patients achieving a PSA decline of  ≥ 30% (PSA30) from baseline after 6 weeks on AA + D. Secondary endpoints included: PSA50 response rate at 12 weeks, time to biochemical and radiological progression, overall survival, safety profile evaluation, benefit from subsequent treatment lines and the identification of biomarkers of response (AR copy number, TMPRSS2-ERG status and PTEN expression).

RESULTS

Twenty-six patients were enrolled. PSA30 and PSA50 were 46.2% and 34.6%, respectively. Median time to biochemical and radiological progression were 5.3 and 11.8 months, respectively. Two radiological responses were observed. Median overall survival was 20.9 months. Patients with AR gain detected in plasma circulating tumour DNA did not respond to switch, whereas patients with AR normal status benefited the most. No significant toxicities were observed and PSA50 response rate to subsequent taxane was 50%.

CONCLUSIONS

In selected clinical stable mCRPC patients with limited disease progression on AA + P, a steroid switch from prednisone to dexamethasone can lead to PSA and radiological responses.

Importance of 68Ga-PSMA PET/CT in hospital practice. View of the radiation oncologist

Radiotherapy is a treatment with curative intent, both in patients with primary diagnosis of prostate cancer (PCa) and in patients presenting with biochemical recurrence after radical prostatectomy (RP). Moreover, the use of stereotactic body radiotherapy as a metastasis directed therapy in patients with oligometastatic PCa has significantly increased in the recent years. Conventional imaging techniques, including transrectal ultrasound, computed tomography (CT), morphologic magnetic resonance and bone scintigraphy have traditionally played a minor role in all those clinical scenarios due to its low diagnostic accuracy. The recent development of the positron emission tomography (PET) radiotracer ⁶⁸Ga-PSMA binding to the prostate specific membrane antigen (PSMA), a transmembrane glycoprotein overexpressed in PCa cells, has shown promising results. Detection rates for PCa lesions are higher than CT and higher than the best technique available, the PET/CT with choline. Its superiority has been demonstrated even at very low PSA levels (<1 ng/ml). This increase in diagnostic accuracy represents a potential impact on patient management, especially in radiotherapy. Even if this imaging technique is already available for routine clinical practice in some European countries, in Spain, unfortunately, there is very limited access. In this review, we analyze the main studies that investigate the usefulness of ⁶⁸Ga-PSMA PET/CT in patients with PCa and its potential impact on radiotherapy treatments. In addition, we compared the ⁶⁸Ga-PSMA PET/CT, with the multiparametric magnetic resonance imaging and the PET/CT with choline, in the different clinical scenarios.

Rectal adenocarcinoma: Outcomes of adjuvant chemotherapy after neoajuvant chemoradiotherapy in a retrospective cohort

790

Background: The role of adjuvant chemotherapy (AC) after chemoradiotherapy and surgery in stage II and III of rectal cancer is not well defined. Neither the regimen nor the duration is clear. Besides, guidelines from different expert groups are conflicting. Methods: 224 patients diagnosed from January 2003 to December 2013 with rectal adenocarcinoma T3/T4 and/or positive node staged by ultrasound or magnetic resonance imaging was collected retrospectively from the Pathology Department data base. Results: Of the 224 patients 61.6% were male, median of age at diagnosis 68.6 years (range 31.3-85.4). All of them received 50.4 Gy with different concomitant regimens (capecitabine, continuous infusion of fluoracil or bolus of fluoracil-leucovorin). 13.4% of patients achieved a pathological complete response. 76.8% of the cohort received adjuvant chemotherapy. The main reasons for not receiving chemotherapy were ECOG ≥ 2, surgery complications and a decision of the patient. 51.2% of patients received an oxaliplatin based regimen and the median time of chemotherapy duration was 4 months (range 1-6 months). Local relapse was diagnosed in 6.3% of patients while a systemic relapse was found in 22.3%. Patients without AC had a mean overall survival (OS) of 85.5 months (CI 95% 70.7-100.4) versus 119.8 monts (CI 95% 110.8-128.8) in the AC cohort (p 0.002) without reaching the median after 58 months (range 8-153.9) median follow-up. Disease free survival (DFS) was also better in the AC cohort with a mean DFS of 104 months (CI 95% 94.3-113.6) versus 71.4 months (CI 95% 55.4-87.4), p = 0.01. Conclusions: AC after chemoradiotherapy and surgery in stage II and III rectal cancer as a standard does not exist. In our cohort, AC showed a significant improve in OS and DFS, but the limitations of a retrospective study should be considered, as well as the impact of surgery on metastasis and salvage chemotherapies. Randomized studies are clearly needed.