Testosterone recovery after androgen deprivation therapy in localised prostate cancer: Long-term data from two randomised trials

BACKGROUND AND PURPOSE

To determine the rate and time of testosterone (T) recovery in patients (pts) with localised prostate cancer treated with radiotherapy plus 0-, 6-, 18- or 36-month of androgen deprivation therapy (ADT).

MATERIALS AND METHODS

In 1230 pts with prostate cancer randomised into two phase III trials, serum T was measured at baseline, then regularly. T recovery rate was compared between normal vs. abnormal baseline T and with ADT duration with Chi-square test or Fisher's exact test. A multivariable logistic regression model to predict the probability of recovering normal T was performed.

RESULTS

Overall, 87.4 % (167/191), 75.9 % (293/386), 54.8 % (181/330) and 43.2 % (80/185) of pts, recovered normal T on the 0-, 6-, 18- or 36-month schedule, respectively (p < 0.001). In patients recovering normal T, the median time to T recovery increased with ADT duration ranging from 0.31, 1.64, 3.06 to 5.0 years for the 0-, 6-, 18- or 36-month schedules, respectively (p < 0.001) and was significantly faster for those with a normal T at baseline (p < 0.001). On multivariable analysis, older age and longer ADT duration are associated with a lower T recovery.

CONCLUSIONS

Testosterone recovery rate after ADT depends on several factors including hormonal duration, normal baseline T, age and medical comorbidities. A longer ADT duration is the most important variable affecting T recovery. The data from this report might be a valuable tool to help physicians and patients in evaluating risks and benefits of ADT.

Deep learning for high-resolution dose prediction in high dose rate brachytherapy for breast cancer treatment

Objective.Monte Carlo (MC) simulations are the benchmark for accurate radiotherapy dose calculations, notably in patient-specific high dose rate brachytherapy (HDR BT), in cases where considering tissue heterogeneities is critical. However, the lengthy computational time limits the practical application of MC simulations. Prior research used deep learning (DL) for dose prediction as an alternative to MC simulations. While accurate dose predictions akin to MC were attained, graphics processing unit limitations constrained these predictions to large voxels of 3 mm × 3 mm × 3 mm. This study aimed to enable dose predictions as accurate as MC simulations in 1 mm × 1 mm × 1 mm voxels within a clinically acceptable timeframe.Approach.Computed tomography scans of 98 breast cancer patients treated with Iridium-192-based HDR BT were used: 70 for training, 14 for validation, and 14 for testing. A new cropping strategy based on the distance to the seed was devised to reduce the volume size, enabling efficient training of 3D DL models using 1 mm × 1 mm × 1 mm dose grids. Additionally, novel DL architecture with layer-level fusion were proposed to predict MC simulated dose to medium-in-medium (Dm,m). These architectures fuse information from TG-43 dose to water-in-water (Dw,w) with patient tissue composition at the layer-level. Different inputs describing patient body composition were investigated.Main results.The proposed approach demonstrated state-of-the-art performance, on par with the MCDm,mmaps, but 300 times faster. The mean absolute percent error for dosimetric indices between the MC and DL-predicted complete treatment plans was 0.17% ± 0.15% for the planning target volumeV100, 0.30% ± 0.32% for the skinD2cc, 0.82% ± 0.79% for the lungD2cc, 0.34% ± 0.29% for the chest wallD2ccand 1.08% ± 0.98% for the heartD2cc.Significance.Unlike the time-consuming MC simulations, the proposed novel strategy efficiently converts TG-43Dw,wmaps into preciseDm,mmaps at high resolution, enabling clinical integration.

Hypofractionated, Dose Escalation Radiation Therapy for High-Risk Prostate Cancer: The Safety Analysis of the Prostate Cancer Study-5, a Groupe de Radio-Oncologie Génito-Urinaire de Quebec Led Phase 3 Trial

PURPOSE

The low α\β ratio of 1.2 to 2 for prostate cancer (PCa) suggests high radiation-fraction sensitivity and predicts a therapeutic advantage of hypofractionated (HF) radiation therapy (RT). To date, no phase 3 randomized clinical trial has compared moderately HF RT with standard fractionation (SF) exclusively in high-risk PCa patients. We are reporting the safety of moderate HF RT in high-risk PCa in an initially noninferiority-designed phase 3 clinical trial.

METHODS AND MATERIALS

From February 2012 to March 2015, 329 high-risk PCa patients were randomized to receive either SF or HF RT. All patients received neoadjuvant, concurrent, and long-term adjuvant androgen deprivation therapy. Standard fractionation RT consisted of 76 Gy in 2 Gy per fraction to the prostate, where 46 Gy was delivered to the pelvic lymph nodes. Hypofractionated RT included concomitant dose escalation of 68 Gy in 2.72 Gy per fraction to the prostate and 45 Gy in 1.8 Gy per fraction to the pelvic lymph nodes. The coprimary endpoints were acute and delayed toxicity at 6 and 24 months, respectively. The trial was originally designed as a noninferiority with a 5% absolute margin. Given the lower-than-expected toxicities in both arms, the noninferiority analysis was completely dropped.

RESULTS

Of the 329 patients, 164 were randomized to the HF and 165 to the SF arms. In total, there were more grade 1 or worse acute gastrointestinal (GI) events in the HF arm, 102 versus 83 events in the HF and SF arm, respectively (P = .016). This did not remain significant at 8 weeks of follow-up. There were no differences in grade 1 or worse acute GU events in the 2 arms, 105 versus 99 events in the HF and SF arm, respectively (P = .3). At 24 months, 12 patients in the SF arm and 15 patients in the HF arm had grade 2 or worse delayed GI-related adverse events (hazard ratio, 1.32; 95% CI, 0.62-2.83; P = .482). There were 11 patients in the SF arm and 3 patients in the HF arm with grade 2 or higher delayed genitourinary (GU) toxicities (hazard ratio, 0.26; 95% CI, 0.07-0.94; P = .037). There were 3 grade 3 GI and one grade 3 GU delayed toxicities in the HF arm and 3 grade 3 GU and no grade 3 GI toxicities in the SF arm. No grade 4-toxicities were reported.

CONCLUSIONS

This is the first study of moderate HF dose-escalated RT in exclusively high-risk patients with prostate cancer treated with long-term androgen deprivation therapy and pelvic RT. Although our data were not analyzed as a noninferiority, our results demonstrate that moderately HF RT is well-tolerated, similar to SF RT at 2 years, and could be considered an alternative to SF RT.

Prophylactic Α-Blockers for Radiotherapy-Induced LUTS in Men with Prostate Cancer: A Phase III Randomized Trial Analysis

PURPOSE/OBJECTIVE(S)

Radiation therapy (RT) to the pelvis is one of the curative approaches for patients with localized prostate cancer. Most patients treated with prostate RT experience some degree of radiation-induced lower urinary tract symptoms (RI-LUTS). The present phase III randomized trial assessed the efficacy of prophylactic versus therapeutic α-blockers at improving RI-LUTS in prostate cancer patients receiving external beam radiotherapy (EBRT).

MATERIALS/METHODS

A total of 148 prostate cancer patients were randomized 1:1 to receive either prophylactic Silodosin at day one of EBRT or at the time of RI-LUTS. LUTS were quantified using the International Prostate Symptom Score (IPSS) at regular intervals during the study. The primary endpoint was the change in the IPSS from baseline to the last day of radiotherapy (RT). Secondary endpoints included changes in IPSS from baseline to 4 weeks and 12 weeks after the start of RT.

RESULTS

Patient demographics, baseline IPSS and prescribed radiation doses were balanced between arms. On the last day of RT, the mean IPSS was 14.8 (SD 7.6) in the experimental arm and 15.7 (SD 8.5) in the control arm (95% CI -4.5 to 1.8, p = .40). There were no significant differences in IPSS between the study arms in the intention-to-treat (ITT) analysis at baseline, last day of RT, 4 weeks and 12 weeks post-RT. The as-treated analysis however, identified statistically significant difference at 4 weeks post-RT (95% CI -6.4 to -0.4, p = .03) in favor of prophylactic α-blockers. In an exploratory analysis, patients with prostate volumes less than or equal to 50 cc benefited at 4 weeks post-RT from prophylactic α-blocker (95% CI -8.4 to -0.3, p = .04).

CONCLUSION

Prophylactic α-blocker was not effective at significantly reducing RI-LUTS in prostate cancer patients treated with EBRT. Treating patients with α-blocker at the onset of RI-LUTS will avoid unnecessary drug exposure and toxicity. There may be a benefit for prophylactic α-blocker in patients with smaller prostate. This however, needs to be further studied in a larger study.

Biochemical Failure in Intermediate Risk Prostate Cancer: Then What? Long-Term Data from a Phase III Trial

PURPOSE/OBJECTIVE(S)

Aiming to determine long-term outcomes post biochemical failure (BF) in patients (pts) treated for intermediate-risk prostate cancer, we analyzed data from our prospective randomized trial (PCS III).

MATERIALS/METHODS

From December 2000 to September 2010, 600 pts with intermediate risk prostate cancer (IRPC) received prostate radiotherapy (RT) with or without short-term (6 months) androgen deprivation therapy (ADT) on a Phase III trial. We report death rate from prostate cancer, rate and timing of BF plus the final clinical outcome of patients, alive or dead, with BF. Chi-squared test was used to compare BF and prostate cancer progression (PCP) rates between patient with or without ADT.

RESULTS

Median age at randomization was 71 years (IQR 66-74). With a median follow-up (FU) of 13.5 years (IQR 11.2-17.0), 74.5% (447/600) were free from BF at last FU. Of these, 211 died, 79 stopped FU after 10 years, 9 were lost to FU, 6 withdrew from the study and 142 are still on FU, at a median follow-up of 13.2 years (IQR = 10.9 - 16.2). A total of 153 pts (25.5%) developed BF at a median time of 6.5 years post-randomization. Among BF pts, 82/153 died: we documented 32 deaths from prostate cancer (DPC) at a median time of 6 years post-BF and 50/153 pts died from other causes at a median time of 4.7 years from BF. 48/153 BF pts continue on FU: 34 show no clinical evidence of cancer, 9 developed a second cancer and 5 show clinical evidence of PCP. 20/153 pts stopped FU after 10 years: 3 of them with PCP. 3/153 pts were lost to FU: 1 after 3 years with prostate bone metastasis and 2 after 13 years of FU. In the first 5 years post-randomization, 47 pts (7.8%) presented BF with 1 (0.2%) DPC; between 6 and 10 years, there were another 84 (14%) BFs and 11 (1.8%) DPC. Finally, after 10 years and beyond, we recorded an additional 22 (3.7%) BFs and 20 (3.3%) DPC. The rate of patients who received ADT was significantly lower in patients with BF (74/153 = 48.4%) compared to patients without BF (324/447 = 72.5%), p<0.001. The rate of patients who received ADT was also significantly lower in patients with PCP (19/48 = 39.6%) compared to patients without PCP (379/552 = 68.7%), p<0.001.

CONCLUSION

In our trial for intermediate-risk prostate cancer, a quarter of the pts developed BF. Most of the BFs occurred between 5- and 10- year post-randomization. Deaths due to prostate cancer post-BF occurred at a median time of 6 years, justifying the need for long-term FU. BF and PCP were significantly higher in patients not receiving ADT.

Patient Reported Outcomes in High-Risk Prostate Cancer Patients with or without Testosterone Recovery after Androgen Deprivation Therapy

PURPOSE/OBJECTIVE(S)

In a previous report from a randomized trial of 630 patients (pts), we showed that 18 months of androgen deprivation therapy (18m ADT) appears to be equally effective as 36 months (36m ADT) in high-risk prostate cancer (HRPC) pts. We performed the current analysis to evaluate quality of life (QOL) using the 25 items of EORTC PR25 validated tool in pts with or without testosterone (T) recovery after ADT.

MATERIALS/METHODS

We selectedpts with no biochemical failure to avoid subsequent T variations due to reintroduction of ADT for recurrence. Patients receiving exactly 18 or 36m of ADT, survived more than one year (y) post randomization, had T measured at baseline and during follow-up and who completed QOL questionnaire entered this review. The 25 items were regrouped into 5 scales. All items and scales scores were linearly transformed to a 0-100 points scale. Serum T was measured at baseline then at each visit. We defined unrecovered testosterone as measured below the normal level. All items and scales scores were analyzed with general linear model and repeated measures to evaluate changes between pts with or without T recovery over time. T recovery was adjusted in a multivariable model including age, initial normal/unrecovered T and ADT (18 or 36m). P-value < 0.01 was considered statistically significant and a difference in mean scores of ≥10 points was considered clinically relevant. Patient-reported outcomes were filled out before treatments, every 6m during ADT, 4m after ADT and then once a year for 5y.

RESULTS

Two hundred sixty nine of 630 pts met the eligibility criteria and were retained for the analysis. At a median follow-up of 14 years, 140/269 (52.0%) pts recovered T to normal level: 94/166 (56.6%) in 18m ADT and 46/103 (44.7%) in 36m ADT, p = 0.056. The median time to recovered T was significantly lower in 18m vs. 36m ADT (3.04 vs. 5.06 y, p<0.001). The global adherence to QOL questionnaires was 83.9% (2649/3156) and was similar between arms. Pts recovering T compared to those who did not, had a better QOL. 6/20 items [difficult to get enough sleep: get up frequently at night to urinate, blood in stool, hot flushes, feel less man, interested in sex, sexually active (with or without intercourse)] and 2/4 scales (treatment and sexual activity) were statistically significant (all p<0.01). 2 items were also clinically relevant: hot flushes and interested in sex. Hot flushes were clinically relevant (more than 10 point of difference) between 3.5 to 5y inclusively with maximum difference of 19.4 point. Interest in sex was clinically relevant with 13.1 point of difference at 3 years.

CONCLUSION

T recoverypost long-term ADT is associated with a significantly improved QOL in patients with HRPC. Considering similar prostate cancer clinical outcomes and faster T recovery, our results suggest that 18m ADT may be the most appropriate ADT treatment duration for these patients.

Conventional vs. Hypo-Fractionated, Radiotherapy for High-Risk Prostate Cancer (PCS5), Randomized, Non-Inferiority, Phase 3 Trial: Posthoc Analysis of IMRT vs. 3D-CRT Radiation Therapy Associated Toxicities

PURPOSE/OBJECTIVE(S)

The Prostate Cancer Study number 5 (PCS5), is a multi-centric non-inferiority, phase 3, randomized controlled trial of high-risk prostate cancer patients of treated with either conventionally fractionated radiotherapy (CFRT) or hypofractionated radiotherapy (HFRT). The 7 years' pre-planned analysis showed that HFRT (68 Gy in 25 fractions) was as effective and well tolerated as CFRT (76 Gy in 38 fractions). In this posthoc analysis we aim to report the genitourinary (GU) and gastrointestinal (GI) toxicities associated with radiation therapy techniques: intensity-modulated radiotherapy (IMRT) and 3D-conformal radiotherapy (3D-CRT).

MATERIALS/METHODS

PCS5 randomized patients in a 1:1 ratio to receive either CFRT or HFRT. All patients received long term neoadjuvant, concurrent and adjuvant androgen suppression, with a median duration of 24 months. The toxicities were reported as per the Common Terminology Criteria for Adverse Events version 4. Acute toxicities were defined as presenting ≤ 180 days post-RT start and delayed > 180 days. The cumulative acute and delayed GI and GU toxicities were classified in grade groups: grade 1 or higher (G1+), G2+, and G3+. For each grade group, acute and delayed, we performed multivariable logistic regression analyses, adjusting for age, CTV volume, diabetes, fractionation (CRFT or HFRT), hypertension, and stage < T3b or ≥ T3b. For efficacy analyses cox-regression was utilized. A p-value < 0.05 was considered significant.

RESULTS

Three hundred twenty of the 329 patients enrolled in the trial were included in this posthoc analyses. The mean age was 71.4 ± 6.1 years, and the mean CTV volume (n = 219) was 47.25 ± 19.9 cc. IMRT was used in 195 (60.6%) patients and 3D-CRT in 125 (39.1%) patients. Multivariable logistic regression showed a significant difference in favor of IMRT for GI G2+ acute toxicity (OR = 0.285 [0.14-0.59]; CI: 95%; p<0.001) and GI G2+ delayed toxicity (OR = 0.202 [0.60-0.69]; CI: 95%; p = 0.01). There were no differences in G3+ GI or GU toxicities and there were no grade 4 toxicities. There were no differences in efficacy at 7 years between the two treatment technics. Outcomes for IMRT vs. 3D-CRT respectively, overall survival (81.5% vs 79.2%; HR: 0.92 [0.55-1.53]; CI: 95%; p-value: 0.74), distant metastasis free survival (90,7% vs 92.8%; HR: 1.4 [0.63-3.1]; CI: 95%; p-value: 0.42), prostate cancer mortality (95.8% vs. 92.2%; HR: 0.93 [0.32-2.67]; CI: 95%; p-value: 0.89), and biochemical failure (85.1% vs 88%; HR: 1.35 [0.72-2.52]; CI: 95%; p-value: 0.35).

CONCLUSION

This is the first phase 3 randomized controlled trial assessing the use of HFRT vs. CFRT, exclusively in high-risk prostate cancer patients. Given that our efficacy data at 7 years follow-up establishes moderate HFRT as a new standard of care and no difference between IMRT and 3D-CRT, we strongly recommend that patients who are treated with EBRT should receive IMRT, given the reduced acute and delayed grade 2 or higher GI toxicities.

Phase III Study of Hypofractionated, Dose Escalation Radiotherapy vs. Conventional Pelvic Radiation Therapy followed by High Dose Rate Brachytherapy Boost for High Risk Adenocarcinoma of the Prostate (PCS VI): Acute Toxicity Results

PURPOSE/OBJECTIVE(S)

The low α\β ratio of 1.2-2 for prostate cancer (PCa) suggests high radiation-fraction sensitivity and predicts a therapeutic advantage of lager fraction size. We have recently shown (PCS5) that high risk prostate cancer patients can safely and effectively be treated with moderate hypofractionated radiation therapy (HF-RT). To date there has been no phase-III randomized clinical-trial comparing moderately HF-RT with EBRT and HDR boost (HDRB). We are reporting the acute safety of EBRT+HDRB compared to moderate HF-RT in this phase III Canadian trial.

MATERIALS/METHODS

From January 2015-June 2022, 308 high-risk localized PCa patients were randomized to receive either HF-RT or EBRT+HDRB. All patients received neo-adjuvant, concurrent, and long-term adjuvant androgen deprivation therapy (ADT). EBRT+HDRB consisted of 46 Gy in 2 Gy per fraction to the pelvis and a 15 Gy in one fraction HDR boost within 3 weeks of EBRT. HF-RT include concomitant dose escalation of 68 Gy in 2.72 Gy per fraction to the prostate, and 45 Gy in 1.8 Gy per fraction to the pelvic lymph-nodes.

RESULTS

Of the 308 patients, 148 received HF-RT and 144 EBRT+ HDRB. The remainder either withdrew from the study or were treated with standard (2 Gy per fraction) fractionation for technical reasons. In both intention to treat and as treated analysis, using log-Rank, there were more grade 1 or worse (G1+) acute GI and GU events and more G2+ acute GI events in the HF-RT than EBRT+HDRB. As treated analysis the acute G1+ and G2+ GI events were 92 vs 77 (60.1% vs. 53.5%; p < 0.017) and 21 vs 10 (13.7% vs. 6.9%; p = 0.052), respectively for HF-RT and EBRT + HDRB. Similarly, the G1+ acute GU events were 123 vs. 101 (80.4% vs.70.1%; p < 0.001) respectively for HF-RT and EBRT+HDRB. There were only four G3 GI and one G3 GU acute toxicities in both arms. No grade 4 toxicities were reported.

CONCLUSION

This is the first study of EBRT+HDRB compared to moderate HF dose escalated RT in high-risk prostate cancer patients treated with long-term ADT and pelvic RT. Our results demonstrate that both treatment approaches are well-tolerated and that EBRT+HDRB carries less G2+ GI and G1+ GU acute toxicities.

Salvage Whole-Pelvic Radiation and Long-Term Androgen-Deprivation Therapy in the Management of High-Risk Prostate Cancer: Long-Term Update of the McGill 0913 Study

PURPOSE

To report the long-term outcomes of the McGill 0913 study and the potential benefits of combining prostate-bed radiotherapy (PBRT), pelvic-lymph-node radiotherapy (PLNRT), and long term ADT (LT-ADT).

MATERIALS AND METHODS

From 2010 to 2016, 46 high-risk prostate cancer patients who experienced biochemical recurrence (BCR) after radical prostatectomy (RP) were enrolled in this single-arm phase II clinical trial. The patients were eligible if they had a Gleason score > 8, locally advanced disease (≥pT3), a preoperative PSA of >20 ng/mL, or positive lymph nodes (LN). The patients were treated with a combination of 24 months of ADT, PBRT, and PLNRT. The primary outcome was biochemical progression-free survival (bPFS) and the predefined secondary endpoints included distant-metastasis-free survival (DMFS), overall survival (OS), and toxicity. In this update, we also report the median follow-up of 8.8 years and 10 years OS.

RESULTS

At a median follow-up of 8.8 years, 43 patients were eligible for analysis. The median pre-salvage PSA was 0.30 μg/L. Half (51%) of the patients (n = 22) had positive margins, 40% (n = 17) had Gleason scores > 8, 63% (n = 27) had extracapsular extension, 42% (n = 18) had seminal vesicle invasion, and 19% (n = 8) had LN involvement. The 10-year bPFS was 68.3 %. The 10-year DMFS was 72.9%. The 10-year OS was 97%. There were two non-cancer-related deaths. The first patient died of congestive heart failure while the other died of an unknown cause. No new toxicity was observed after the initial report.

CONCLUSIONS

Our study demonstrates that treatment escalation with PBRT, PLNRT, and LT-ADT improves long term outcomes. In view of the recently published SPPORT study, we conclude that this novel approach of treatment intensification in high-risk post-prostatectomy patients is safe and effective, and that it should be offered as the standard of care.

Prophylactic A-Blockers for Radiotherapy-Induced Lower Urinary Tract Symptoms in Men with Prostate Cancer: A Phase III Randomized Trial

PURPOSE

The present phase III randomized trial assessed the efficacy of prophylactic versus therapeutic α-blockers at improving RI-LUTSs in prostate cancer patients receiving external beam radiotherapy (EBRT).

METHODS

A total of 148 prostate cancer patients were randomized 1:1 to receive either prophylactic silodosin on day one of EBRT or the occurrence of RI-LUTSs. LUTSs were quantified using the international prostate symptom score (IPSS) at regular intervals during the study. The primary endpoint was the change in the IPSS from baseline to the last day of radiotherapy (RT). Secondary endpoints included changes in IPSS from baseline to 4 weeks and 12 weeks after the start of RT.

RESULTS

Patient demographics, baseline IPSS, and prescribed radiation doses were balanced between arms. On the last day of RT, the mean IPSS was 14.8 (SD 7.6) in the experimental arm and 15.7 (SD 8.5) in the control arm (p = 0.40). There were no significant differences in IPSSs between the study arms in the intention-to-treat (ITT) analysis at baseline, the last day of RT, and 4 and 12 weeks post-RT.

CONCLUSION

Prophylactic α-blockers were not effective at significantly reducing RI-LUTSs in prostate cancer patients treated with EBRT. Treating patients with α-blockers at the onset of RI-LUTSs will avoid unnecessary drug exposure and toxicity.

Neoadjuvant versus Concurrent Androgen Deprivation Therapy in Localized Prostate Cancer Treated with Radiotherapy: A Systematic Review of the Literature

BACKGROUND

There is an ongoing debate on the optimal sequencing of androgen deprivation therapy (ADT) and radiotherapy (RT) in patients with localized prostate cancer (PCa). Recent data favors concurrent ADT and RT over the neoadjuvant approach.

METHODS

We conducted a systematic review in PubMed, EMBASE, and Cochrane Databases assessing the combination and optimal sequencing of ADT and RT for Intermediate-Risk (IR) and High-Risk (HR) PCa.

FINDINGS

Twenty randomized control trials, one abstract, one individual patient data meta-analysis, and two retrospective studies were selected. HR PCa patients had improved survival outcomes with RT and ADT, particularly when a long-course Neoadjuvant-Concurrent-Adjuvant ADT was used. This benefit was seen in IR PCa when adding short-course ADT, although less consistently. The best available evidence indicates that concurrent over neoadjuvant sequencing is associated with better metastases-free survival at 15 years. Although most patients had IR PCa, HR participants may have been undertreated with short-course ADT and the absence of pelvic RT. Conversely, retrospective data suggests a survival benefit when using the neoadjuvant approach in HR PCa patients.

INTERPRETATION

The available literature supports concurrent ADT and RT initiation for IR PCa. Neoadjuvant-concurrent-adjuvant sequencing should remain the standard approach for HR PCa and is an option for IR PCa.

Advances in PARP Inhibitors for Prostate Cancer

Poly-adenosine diphosphate-ribose polymerase plays an essential role in cell function by regulating apoptosis, genomic stability and DNA repair. PARPi is a promising drug class that has gained significant traction in the last decade with good outcomes in different cancers. Several trials have sought to test its effectiveness in metastatic castration resistant prostate cancer (mCRPC). We conducted a comprehensive literature review to evaluate the current role of PARPi in this setting. To this effect, we conducted queries in the PubMed, Embase and Cochrane databases. We reviewed and compared all major contemporary publications on the topic. In particular, recent phase II and III studies have also demonstrated the benefits of olaparib, rucaparib, niraparib, talazoparib in CRPC. Drug effectiveness has been assessed through radiological progression or overall response. Given the notion of synthetic lethality and potential synergy with other oncological therapies, several trials are looking to integrate PARPi in combined therapies. There remains ongoing controversy on the need for genetic screening prior to treatment initiation as well as the optimal patient population, which would benefit most from PARPi. PARPi is an important asset in the oncological arsenal for mCRPC. New combinations with PARPi may improve outcomes in earlier phases of prostate cancer.

Testosterone recovery in patients with prostate cancer treated with radiotherapy and different ADT duration: Long-term data from two randomized trials

300

Background: To determine the rate and time of testosterone (T) recovery to normal level in patients (pts) with prostate cancer treated with radiotherapy plus 6, 18 or 36 months of androgen deprivation therapy (ADT) and considered cured from their disease. Methods: We randomized 1230 pts with prostate cancer, into two phase III trials: 600 with intermediate risk and 630 with high-risk. We selected those considered cured to avoid subsequent T variations due to reintroduction of ADT for recurrence. We excluded the following pts: no ADT at all (126) or not receiving exactly 6, 18 or 36 months of ADT (69), survival less than one year (21), no T measured at baseline or during follow-up (75), biochemical failure (195) or evidence of metastatic/recurrent disease (137).T recovery rate was compared between baseline normal/abnormal T (values below biochemical normal range) and by ADT duration with Chi-square test or Fisher's exact test. A multivariable logistic regression model to predict the probability of recovering normal T was performed by including normal/abnormal T at baseline, age, Zubrod, comorbidities and ADT duration. A second model was performed by replacing ADT duration with baseline PSA, Gleason score and stage. The median time to T recovery was calculated only on pts who recovered normal T. Results: Results are reported with a median follow-up of 14 years. 607 pts fit the criteria and are available for analysis: 309 pts in the 6 months ADT schedule, 185 in the 18 and 113 in the 36. Overall, 76.7%, 54.6% and 45.1% pts recovered normal T on the 6, 18 or 36 months schedule, respectively (p<0.001). The median time to T recovery was 1.5, 3.1, and 5.1 years for the 6, 18 or 36 months schedule, respectively (p<0.001). 79.7% presented with a normal T at baseline while 20.3% had an abnormal T level. By splitting pts between a normal vs. abnormal presenting T level, the T recovery rate was as follows: 82.1%, 63.3%, and 50% for the normal T cohort, compared to 53.4%, 28.3% and 21.1% for the abnormal T cohort at 6, 18 or 36 months, respectively. There was a significant difference in the overall recovery rate (p<0.001) between normal vs. abnormal T level and at all ADT duration lengths between the two cohorts. In multivariable model, baseline normal T was a strong predictor of T recovery. Older age, diabetes, longer ADT, higher clinical stage, higher PSA and higher Gleason score reduced significantly the chance for T recovery. In pts recovering T post-ADT, except for the 6 months duration (p=0.01), the median time for T recovery was not significantly different between normal or abnormal T at baseline in 18 and 36 months cohorts. Conclusions: Older age, longer ADT and poor disease features are associated with a lower T recovery. Even after adjusting for several variables and ADT duration, a higher T recovery post-ADT is significantly associated with a normal T at baseline.

Is sentinel lymph node assessment useful in patients with a preoperative diagnosis of endometrial intraepithelial neoplasia?

OBJECTIVE

To determine the prevalence of underlying high-intermediate (high-IM) and high-risk endometrial cancer (EC) in patients with preoperative diagnosis of Endometrial intraepithelial neoplasia (EIN) and to assess the impact of the information retrieved from the sentinel lymph node (SLN) on adjuvant therapy.

METHODS

Retrospective cohort study of women undergoing hysterectomy, optional bilateral salpingo-oophorectomy (BSO) and lymph nodes assessment for EIN between December 2007 and August 2021.

RESULTS

One hundred and sixty two (162) eligible patients were included, of whom 101 (62.3%) had a final diagnosis of EIN, while 61 (37.7%) were ultimately diagnosed with carcinoma. Out of 15 patients with high-IM to high-risk disease (9.25% of all EIN), 12 had grade 2-3 EC including 8 with >50% myometrial invasion, 2 with serous subtype, 1 with cervical invasion and 2 with pelvic lymph nodes involvement. Of the 3 patients with grade 1 EC, one patient had disease involving the adnexa and 2 patients had tumor invading >50% of the myometrium and with lymphovascular space invasion (LVSI). Ten patients received vaginal brachytherapy after surgery, 3 patients with extrauterine spread were treated with systemic chemotherapy followed by vaginal brachytherapy and pelvic external-beam radiotherapy and 2 patients with early-stage serous carcinoma received chemotherapy followed by vaginal brachytherapy.

CONCLUSIONS

Information from SLN, even when negative, can be helpful in the management of patients with EC after preoperative EIN, as some patients are found to have high-IM to high-risk disease on final pathology. These patients would require either re-staging surgery or adjuvant external beam radiotherapy, both could be avoided by proper staging.

Salvage external beam radiotherapy after HIFU failure in localized prostate cancer: A single institution experience

Purpose/objectives

High-intensity focused ultrasound (HIFU) remains investigational as primary treatment for localized prostate cancer but is sometimes offered to select patients. At HIFU failure, data guiding salvage treatment is limited to small retrospective series with short follow-up. We evaluated our institutional experience using salvage radiation therapy (SRT) after HIFU failure.

Materials/methods

We conducted a retrospective analysis of patients with local failure post-HIFU who received salvage image-guided external beam radiation therapy (EBRT) delivered via intensity-modulated radiotherapy (IMRT). Our primary endpoint was biochemical failure-free survival (bFFS) defined as prostate-specific antigen (PSA) nadir + 2 ng/mL. Secondary endpoints included metastasis-free survival (MFS) and overall survival (OS). Endpoints were evaluated using Kaplan-Meier analysis.

Results

From 2013 to 2018, 12 out of 96 patients treated with primary HIFU received SRT via conventional or moderate hypofractionation. Median time from HIFU to SRT was 13.5 months. Seven patients had stage migration to high-risk disease at the time of SRT. Mean PSA prior to SRT was 8.2ug/L and mean nadir post-SRT was 1.2ug/L. Acute International Prostate Symptom Score (IPSS) as well as International Index of Erectile Dysfunction (IIEF) scores were similar to baseline (p = 0.5 and 0.1, respectively). Late toxicities were comparable to those reported after primary EBRT for localized prostate cancer. At a median follow-up of 46 months, the OS was 100%. The 5-year bFFS and MFS were both 83.3%.

Conclusions

To our knowledge, we report one of the largest series on contemporary SRT post HIFU failure. We show that SRT is feasible, effective and carries no additional acute or delayed toxicity.

Optimizing Treatment in Intermediate-Risk Prostate Cancer: Secondary Analysis of a Randomized Phase 3 Trial

PURPOSE

To identify patients with intermediate-risk prostate cancer (IRPC) benefiting from de-escalation of androgen deprivation therapy (ADT) and/or dose escalated radiation therapy (DERT), we performed a secondary analysis of a phase 3 trial by measuring biochemical failure (BF), distant metastases, prostate cancer-specific mortality, overall survival (OS), and distant metastases-free survival (DMFS) rates according to prognostic intermediate risk factors (IRF).

METHODS AND MATERIALS

The initial trial randomized 600 patients with IRPC to a 3-arm trial with 200 patients per arm, consisting of 6 months of ADT plus 70 Gy radiation therapy (ADT + RT70) versus ADT plus a DERT of 76 Gy (ADT + DERT76) versus DERT of 76 Gy alone (DERT76). We performed an analysis based on IRF: clinical stage, prostate-specific antigen level, Gleason score, percentage of positive biopsy cores (PBC) ≥50%, and Gleason pattern. Patients were allocated to 2 groups: favorable intermediate risk (FIR), defined as patients with only 1 IRF without Gleason pattern 4 + 3 or PBC ≥50%; and unfavorable intermediate risk (UIR), defined as all other patients. BF, distant metastases, prostate cancer-specific mortality, OS, and DMFS were compared between FIR and UIR.

RESULTS

The median follow-up was 11.3 years (interquartile range, 10.9-11.7). In the FIR cohort, BF and OS were not significantly different between arms. UIR patients had significantly worse DMFS (hazard ratio [95% confidence interval], 1.61 [1.20-2.15]; P = .026) and OS (1.51 [1.12-2.04]; P = .0495) and a nonsignificant higher cumulative incidence of BF rate (1.55 [0.98-2.47]; P = .08). In UIR patients, a significant improvement in BF was seen in the arms receiving ADT compared to DERT76 alone. On multivariable analysis, Gleason pattern 4 + 3 and prostate-specific antigen >10 ng/mL independently affected BF and OS, regardless of the treatment arm.

CONCLUSIONS

In IRPC, therapeutic optimization appears possible. To avoid ADT side effects, DERT76 alone appears sufficient in patients harboring only 1 risk factor without Gleason pattern 4 + 3 and PBC ≥50% (FIR). All other UIR patients seem to benefit from ADT + DERT76.

The role of brachytherapy for margin control in oral tongue squamous cell carcinoma

BACKGROUND

The aim of this study is to assess the feasibility and effectiveness of using peri-operative brachytherapy (BRTx) for positive/narrow margins present post primary surgical resection of oral tongue squamous cell carcinoma (OTSCC).

METHODS

Prospective single-centre study of patients with OTSCC (T1-3, N0-3, M0) treated with resection of primary tumour ± regional nodal resection and intra-operative insertion of BRTx catheters. BRTx was administered twice daily at 40.8Gy/12Fr for 'Positive' (≤2 mm) margins, at 34Gy/10Fr for 'Narrow' (2.1-5 mm) margins, and not given for 'Clear' (> 5 mm) margins over the course of 5-6 days, 3-5 days post operatively.

RESULTS

Out of 55 patients recruited 41 patients (74.6%) were treated with BRTx, as 12 patients had clear margins and 2 patients had unfavourable tumour anatomy for catheter insertion. EBRTx was avoided in 64.3% of patients. Overall Survival (OS) at 3 and 5 years was 75.6 and 59.1% respectively, while Disease Specific Survival (DSS) was 82.3 and 68.6% at 3 and 5 years respectively. Recurrence and survival outcomes were not associated with margin status or the use of or specific dose of BRTx on Cox regression analysis. Acute and late toxicity secondary to BRTx was minimal.

CONCLUSIONS

The use of BRTx after primary OTSCC resection with positive/narrow margins ± EBRTx to the neck ± CTx achieves outcomes comparable to traditional treatment of surgery followed by re-resection or EBRTx ± CTx. Morbidity associated with oral cavity EBRTx or secondary resection and reconstruction is thus avoided. Both acute and late toxicity rates are low and compare favourably with other BRTx OTSCC studies.

TRIAL REGISTRATION

Retrospectively registered. https://www.mcgill.ca/rcr-rcn/files/rcr-rcn/2017.06.05_rcn_hn.pdf .

LEVEL OF EVIDENCE

4.

No. 370-Management of Squamous Cell Cancer of the Vulva

OBJECTIVE

This guideline reviews the clinical evaluation and management of squamous cell cancer (SCC) of the vulva with respect to diagnosis, primary surgical, radiation, or chemotherapy management and need for adjuvant treatment with chemotherapy and/or radiation therapy. Other vulvar cancer pathologic diagnoses are not included in the guideline.

INTENDED USERS

The first part of this document which includes recommendations 1 through 3 is for general gynaecologists, obstetricians, family doctors, registered nurses, nurse practitioners, residents, and health care providers with a focus on the presentation, diagnosis, and updated information about surgical procedures performed by subspecialists. The surgical management and treatment of advanced vulvar cancer are intended for gynaecologic oncologists, radiation oncologists, and medical oncologists who treat these complex patients. This guideline is intended to provide information for interested parties who may follow these patients once treatment is complete.

TARGET POPULATION

Adult women (18 years and older) with SCC of the vulva. Excluded from these guidelines are women with preinvasive disease.

OPTIONS

Women diagnosed with SCC of the vulva should be referred to a gynaecologic oncologist for initial evaluation, consideration for primary surgery and inguinal lymph node assessment, and potentially adjuvant radiation and/or chemotherapy. All cases of vulvar cancer should have access to discussion at a multidisciplinary cancer case conference. Women who would otherwise require radical surgery such as abdominal-perineal resection or exenterative procedures may be considered for primary treatment with radiation and/or chemotherapy.

EVIDENCE

For this guideline, relevant studies were searched in PubMed, Medline, and the Cochrane Systematic Reviews using the following terms, either alone or in combination, with the search limited to English language materials: vulva, vulvar cancer, inguinofemoral lymph node dissection, sentinel nodes, systemic chemotherapy, radiotherapy, neoadjuvant, adjuvant, primary, exenteration, survival, follow up. The initial search was performed in September 2016 with a final literature search in May 2017. Relevant evidence was selected for inclusion in the following order: meta-analyses, systematic reviews, guidelines, randomized controlled trials, prospective cohort studies, observational studies, non-systematic reviews, case series, and reports. Additional significant articles were identified through cross-referencing the identified reviews. The total number of studies identified was 286, and 78 studies were included in this review.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the principal authors. The Executive and Board of the Society of Gynecologic Oncology of Canada reviewed the content and submitted comments for consideration, and the Board of the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology framework (Table 1). The interpretation of strong and weak recommendations is described in Table 2. The Summary of Findings is available upon request.

BENEFITS, HARMS, AND/OR COSTS

These guidelines are to encourage physicians in the appropriate use of sentinel inguinal lymph node assessment for SCC of the vulva. The committee also promotes the centralization of treatment of vulvar cancer in specialized treatment centres.

GUIDELINE UPDATE

Evidence will be reviewed 5 years after publication to decide whether all or part of the guideline should be updated. However, if important new evidence is published prior to the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations.

SPONSORS

This guideline was developed with resources funded by the Society of Gynecologic Oncology of Canada and the Society of Obstetricians and Gynaecologists of Canada.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Breast cancer in women aged 80 years and older: Clinical characteristics and treatment patterns according to biologic subtype

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Background: Older age is associated with poorer breast cancer-specific survival (BCSS) outcomes, despite a higher prevalence of biologically favorable disease. We sought to evaluate differences in the clinical characteristics and management of older women according to biologic subtype of breast cancer. Methods: The Surveillance, Epidemiology, and End Results (SEER) treatment database was queried to identify all women aged 80 years or older with a first diagnosis of invasive breast cancer between 2010 and 2016. Patients were subgrouped according to biologic subtype and clinical and treatment-related variables were compared. Multivariable logistic regression was then performed to determine factors independently associated with receipt of breast-conserving surgery (BCS) and adjuvant radiation. Results: Overall, 27,375 women with a median age of 84 (range, 80-108 years) met inclusion criteria. The majority of older women were diagnosed with HR+HER2- breast cancer (78.9%), followed by HER2+ (11.0%) and triple-negative breast cancer (TNBC) (10.0%). In women with stage I-III disease, non-operative management was employed in 13.4% of HR+HER2- patients, compared to 16.7% of HER2+ patients and 11.0% of TNBC (p < 0.001). In those undergoing surgery, BCS was most common in HR+HER2- patients (80.9%), compared to HER2+ (68.9%) and TNBC (67.8%; p < 0.001). Axillary surgery was performed in 74.0% of early stage patients with HR+HER2- disease, compared to patients with HER2+ (77.8%) and TNBC (79.3%; p < 0.001). In adjusted analyses controlling for stage and clinical variables, women aged 80 years or older with HER2+ breast cancer and TNBC had a lower likelihood of BCS (ORHER2+ 0.72, 95% CI 0.65-0.80; ORTNBC 0.72, 95% CI 0.65-0.81), and an increased likelihood of adjuvant radiation (ORHER2+ 1.14, 95% CI 1.02-1.27; ORTNBC 1.40, 95% CI 1.25-1.57). Conclusions: One fifth of women with breast cancer over age 80 are diagnosed with HER2+ and triple-negative subtypes, which are associated with more aggressive local therapy. Further studies are warranted to determine if higher rates of adjuvant radiation optimize local control in older HER2+ and TNBC patients at increased risk for early locoregional recurrences.

Combined Long-Term Androgen Deprivation and Pelvic Radiotherapy in the Post-operative Management of Pathologically Defined High-Risk Prostate Cancer Patients: Results of the Prospective Phase II McGill 0913 Study

Purpose: Following radical prostatectomy, prostate bed radiotherapy (PBRT) has been combined with either long-term androgen deprivation therapy (LT-ADT) or short-term ADT with pelvic lymph node radiotherapy (PLNRT) to provide an oncological benefit in randomized trials. McGill 0913 was designed to characterize the efficacy of combining PBRT, PLNRT, and LT-ADT. It is the first study to do so prospectively.

Methods: In a single arm phase II trial conduced from 2010 to 2016, 46 post-prostatectomy prostate cancer patients at a high-risk for relapse (pathological Gleason 8+ or T3) were assessed for treatment with combined LT-ADT (24 months), PBRT, and PLNRT. Patients received PLNRT and PBRT (44 Gy in 22 fractions) followed by a PBRT boost (22 Gy in 11 fractions). The primary endpoint was progression-free survival (PFS). Toxicity and quality of life (QoL) were evaluated using CTCAE V3.0 and EQ-5D-3L questionnaires, respectively.

Results: Among the 43 patients were treated as per protocol, median PSA was 0.30 μg/L. On surgical pathology, 51% had positive margins, 40% had Gleason 8+ disease, 42% had seminal vesicle involvement, and 19% had lymph node involvement. At a median follow-up of 5.2 years, there were no deaths or clinical progression. At 5 years, PFS was 78.0% (95% Confidence Interval 63.7–95.5%). Not including erectile dysfunction, patients experienced: 14% grade 2 endocrine toxicity while on ADT, one incident of long-term gynecomastia, 5% grade 2 acute urinary toxicity, 5% grade 2 late Urinary toxicity, and 24% long-term hypogonadism. No comparison between the average or minimum self-reported QoL at baseline, during ADT, nor after ADT demonstrated a statistically significant difference.

Conclusions: Combining PBRT, PLNRT, and LT-ADT had an acceptable PFS in patients with significant post-operative risk factors for recurrence. While therapy was well-tolerated, long-term hypogonadism was a substantial risk. Further investigations are needed to determine if this combination is beneficial.

Trial registration: NCT01255891.

Does Interfraction Cone Beam Computed Tomography Improve Target Localization in Prostate Bed Radiotherapy?

Purpose:

In this prospective phase II study, we investigated whether cone beam computed tomography scan was a superior method of image-guided radiotherapy relative to 2D orthogonal kilovoltage images in the post-radical prostatectomy setting.

Methods:

A total of 419 treatment fractions were included in this analysis. The shifts required to align the patient for each treatment were performed using 3D matching between cone beam computed tomography scans and the corresponding computed tomography images used for planning. This was compared with the shifts obtained from 2D orthogonal kilovoltage images, matching with the corresponding digitally reconstructed radiographs. Patients did not have fiducials inserted to assist with localization. Interfractional changes in the bladder and rectal volumes were subsequently measured on the cone beam computed tomography images for each fraction and compared to the shift differences between orthogonal kilovoltage and cone beam computed tomography scans. The proportion of treatment fractions with a shift difference exceeding the planning target volume of 7 mm, between orthogonal kilovoltage and cone beam computed tomography scans, was calculated.

Results:

The mean vertical, lateral, and longitudinal shifts resulted from 2D match between orthogonal kilovoltage images and corresponding digitally reconstructed radiographs were 0.353 cm (interquartile range: 0.1-0.5), 0.346 cm (interquartile range: 0.1-0.5), and 0.289 cm (interquartile range: 0.1-0.4), compared to 0.388 cm (interquartile range: 0.1-0.5), 0.342 cm (interquartile range: 0.1-0.5), and 0.291 cm (interquartile range: 0.1-0.4) obtained from 3D match between cone beam computed tomography and planning computed tomography scan, respectively. Our results show a significant difference between the kilovoltage and cone beam computed tomography shifts in the anterior–posterior direction (P = .01). The proportion of treatment fractions in which the differences in kilovoltage and cone beam computed tomography shifts between exceeded the 7 mm planning target volume margin was 6%, 2%, and 3% in the anterior–posterior, lateral, and superior–inferior directions, respectively.

Conclusion:

We prospectively demonstrated that the daily use of volumetric cone beam computed tomography for treatment localization in post-radical prostatectomy patients demonstrated an increased need for a shift in patient position. This suggests that in post-radical prostatectomy patients the daily cone beam computed tomography imaging improved localization of the prostate bed and may have prevented a limited number of geographic misses, compared to daily kilovoltage imaging that was not assisted with fiducials.

Predicting Gleason Score of Prostate Cancer Patients Using Radiomic Analysis

Purpose: Use of quantitative imaging features and encoding the intra-tumoral heterogeneity from multi-parametric magnetic resonance imaging (mpMRI) for the prediction of Gleason score is gaining attention as a non-invasive biomarker for prostate cancer (PCa). This study tested the hypothesis that radiomic features, extracted from mpMRI, could predict the Gleason score pattern of patients with PCa. Methods: This analysis included T2-weighted (T2-WI) and apparent diffusion coefficient (ADC, computed from diffusion-weighted imaging) scans of 99 PCa patients from The Cancer Imaging Archive (TCIA). A total of 41 radiomic features were calculated from a local tumor sub-volume (i.e., regions of interest) that is determined by a centroid coordinate of PCa volume, grouped based on their Gleason score patterns. Kruskal-Wallis and Spearman's rank correlation tests were used to identify features related to Gleason score groups. Random forest (RF) classifier model was used to predict Gleason score groups and identify the most important signature among the 41 radiomic features. Results: Gleason score groups could be discriminated based on zone size percentage, large zone size emphasis and zone size non-uniformity values (p < 0.05). These features also showed a significant correlation between radiomic features and Gleason score groups with a correlation value of -0.35, 0.32, 0.42 for the large zone size emphasis, zone size non-uniformity and zone size percentage, respectively (corrected p < 0.05). RF classifier model achieved an average of the area under the curves of the receiver operating characteristic (ROC) of 83.40, 72.71, and 77.35% to predict Gleason score groups (G1) = 6; 6 < (G2) < (3 + 4) and (G3) ≥ 4 + 3, respectively. Conclusion: Our results suggest that the radiomic features can be used as a non-invasive biomarker to predict the Gleason score of the PCa patients.

Hypofractionated, dose escalation radiotherapy for high-risk prostate cancer: The primary endpoint of a group led phase III trial. (PCS5)

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Background: The low α\β ratio of prostate cancer (PCa), 1.5-2, suggests high radiation-fraction sensitivity and predicts a therapeutic advantage of hypofractionated radiation treatment (HFRT). Most available data of moderate HFRT have focused on low, intermediate and/or mixed risk groups. We therefore conducted the first randomized trial of moderately HFRT in high-risk PCa patients and present the primary safety analysis of side effects at 2 years. Methods: We conducted a Canadian multi-centric phase III trial of conventional fractionated radiation therapy (CFRT) vs. intensity-modulated HFRT in men with high-risk PCa as per NCCN definition. From February 2012 to March 2015, 329 patients were randomized in a 1:1 ratio to receive either CFRT or HFRT. All patients received neo-adjuvant, concurrent and adjuvant androgen suppression, with a median duration of 24 months. CFRT consisted of 76 Gy in 2 Gy per fraction to the prostate where 46 Gy was delivered to the pelvic lymph nodes. HFRT consisted of concomitant dose escalation of 68 Gy in 2.72 Gy per fraction to the prostate and 45 Gy, in 1.8Gy per fraction to the pelvic lymph nodes. The primary endpoint was to compare the toxicities at 6 months and at 24 months using the CTCAE v.4. Results: Of the329 patients, 164 were randomized to HFRT and 165 to CFRT. The minimum, median and maximum follow-up were 24, 40 and 60 months respectively. At 24 months, 12 patients in the CFRT arm and 15 patients in the HFRT arm had grade 2 or worse gastrointestinal (GI)-related adverse events (HR:1.32 [0.62.2.83] 95% CI; P=NS). Similarly, 11 patients in the CFRT arm and 3 patients in HFRT arm had grade 2 or higher genitourinary (GU) toxicities (HR:0.26 [0.07-0.94] 95% CI; P=0.037). In the HFRT arm, there were 3 grade 3 GI and one grade 3 GU related toxicities. In the CFRT arm there were 3 grade 3 GU and no grade 3 GI related toxicities. There were no grade 4 toxicities in either arm. Conclusions: This is the first hypofractionated dose escalated radiotherapy study in high-risk PCa patients treated with contemporary radiation and androgen suppression. Our results indicate that moderate HFRT to high risk PCa patients is equally well tolerated as CFRT at 2 years. Clinical trial information: NCT01444820.

Duration of androgen deprivation therapy in high risk prostate cancer: Final results of a randomized phase III trial

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Background: Long-term androgen deprivation therapy (ADT) combined with radiotherapy (RT) is a standard treatment for patients with high-risk prostate cancer (HRPC). However, the optimal duration of ADT is not yet defined. The aim of this randomized trial (Clinical Trials.gov, #NCT00223171) was to compare outcomes of RT combined with either 36 or 18 months of ADT. Methods: Patients with HRPC were randomized to pelvic and prostate RT combined with 36 (arm 1) or 18 months (arm 2) of ADT. Overall survival (OS) and quality of life (QoL) were primary end points. OS rates were compared with Cox Regression model and QoL data were analyzed through mixed linear model. Results: 630 patients were randomized, 310 to arm 1 and 320 to arm 2. With a median follow-up of 9.4 years, 290 patients had died (147 arm 1 vs. 143 arm 2). The 10-year OS rate was 62.4% (95% confidence interval [CI] 56.4%, 67.8%) for arm 1 and 62.0% (95% CI 56.1%, 67.3%) for arm 2 (p = 0.8412) with a global hazard ratio (HR) of 1.024 (95% CI 0.813-1.289, p = 0.8411). QoL analysis showed a significant difference (p < 0.001) in 6 scales and 13 items favoring 18 months ADT with two of them presenting a clinically relevant difference in mean scores of ≥10 points. Conclusions: In HRPC, ADT combined with RT can be safely reduced from 36 to 18 months without compromising outcomes or QoL. 18 months of ADT represents a new standard of care in HRPC. Funded by AstraZeneca Pharmaceuticals Clinical trial information: NCT00223171.

Is there a relationship between testosterone levels at the end of short-term androgen deprivation therapy and outcomes in intermediate risk prostate cancer? Prospective data from a phase III trial

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Background: The purpose of this analysis was to assess whether the testosterone level measured at the end of short term androgen deprivation therapy (STADT) and prostate radiotherapy (RT) has an impact on treatment outcomes in patients with intermediate risk prostate cancer (IRPC) treated on a randomized trial (PCS III ClinicalTrials.gov #NCT00223145). Methods: From December 2000 to September 2010, 400 patients with IRPC received 6 months of STADT (bicalutamide 50mg die and goserelin 10.8mg x 2) and RT. Castrate level of testosterone was defined as <1.7 nmol/L: lower level <0.7 and upper level 0.7-1.7. In 347/400 patients, testosterone levels were available at the end of STADT and were divided into 3 groups based on measured testosterone levels: <0.7, 0.7 to 1.7 and >1.7 nmol/L. Patient’s characteristics were compared with ANOVA and Fisher’s exact test. Biochemical failure, prostate cancer recurrence and death were compared with Cox regression. Results: Patient’s characteristics were well balanced between the 3 groups with no statistical difference for age, performance status, PSA at start, Gleason score and stage. At the end of STADT 55.3% (192/347) presented testosterone levels <0.7 and 38.9% (135/347) levels between 0.7 and 1.7 for a total of 94.2% (327/ 347) reaching castrate levels ≤1.7 nmol/L. In 5.8% of patients (20/347) a castrate testosterone level was not achieved. With a median follow-up of 8.1 years, outcomes are shown in the table. Conclusions: In IRPC patients treated with STADT and RT, the majority of patients (94.2%) achieve a castrate level of testosterone (<1.7 nmol/L). Although we could not show a difference in outcomes between castrate and non-castrate patients, these data have to be viewed with caution given the small number of non-castrate patients studied. Source of Funding: AstraZeneca Pharmaceuticals Grant. Clinical trial information: NCT00223145. [Table: see text]

Pattern of Local Recurrence and Distant Metastasis in Breast Cancer By Molecular Subtype

BACKGROUND AND PURPOSE

 No longer considered a single disease entity, breast cancer is being classified into several distinct molecular subtypes based on gene expression profiling. These subtypes appear to carry prognostic implications and have the potential to be incorporated into treatment decisions. In this study, we evaluated patterns of local recurrence (LR), distant metastasis (DM), and association of survival with molecular subtype in breast cancer patients in the post-adjuvant radiotherapy setting.

MATERIAL AND METHODS

 The medical records of 1,088 consecutive, non-metastatic breast cancer patients treated at a single institution between 2004 and 2012 were reviewed. Estrogen/progesterone receptors (ER/PR) and human epidermal growth factor receptor-2 (HER2) enrichment were evaluated by immunohistochemistry. Patients were categorized into one of four subtypes: luminal-A (LA; ER/PR+, HER2-, Grade 1-2), luminal-B (LB; ER/PR+, HER2-, Grade > 2), HER2 over-expression (HER2; ER/PR-, HER2+), and triple negative (TN; ER/PR-, HER2-).  Results: The median follow-up time was 6.9 years. During the follow-up, 16% (174/1,088) of patients failed initial treatment and developed either LR (48) or DM (126). The prevalence of LR was the highest in TN (12%) and the lowest in LA (2%). Breast or chest wall relapse was the most frequent site (≈80%) of recurrence in LA, LB, and HER2 subtypes, whereas the regional lymph nodes and chest wall were the common sites of relapse in the TN group (50.0%). DM rates were 6.4% in LA, 12.1% in LB, 19.2% in HER2, and 27.4% in TN subgroups. Five-year survival rates were 84%, 83%, 84%, and 77% in the LA, LB, HER2 and TN subgroups, respectively. There was a statistically significant association between survival and molecular subtypes in an univariate analysis. In the adjusted multivariate analysis, the following variables were independent prognostic factors for survival: T stage, N stage, and molecular subtype.

CONCLUSIONS

 Of the four subtypes, the LA subtype tends to have the best prognosis, fairly high survival, and low recurrent or metastases rates. The TN and HER2 subtypes of breast cancer were associated with significantly poorer overall survival and prone to earlier recurrence and metastases. Our results demonstrate a significant association between molecular subtype and survival. The risk of death and relapse/metastases increases fewfold in TN compared to LA. Future prospective studies are warranted and could ultimately lead to the tailoring of adjuvant radiotherapy treatment fields based on both molecular subtype and the more conventional clinicopathologic characteristics.