Long-term clinical outcomes of salvage pelvic radiation therapy for oligo-recurrent pelvic lymph nodes after definitive external-beam radiation therapy for non-metastatic prostate cancer

High-risk factors and predictive models for hemorrhagic chronic radiation proctitis

INTRODUCTION

Hemorrhagic chronic radiation proctitis (CRP) is a common and challenging complication after pelvic radiation therapy. Identifying high-risk factors, predicting its occurrence, and optimizing radiotherapy plans are key to preventing hemorrhagic CRP. This study retrospectively examined potential risk factors and developed a nomogram to predict its onset.

METHODS

This retrospective study included cervical carcinoma patients who received pelvic radiotherapy at Chongqing University Cancer Hospital from March 2014 to December 2021. Hemorrhagic CRP was diagnosed by colonoscopy. Logistic regression identified factors for a nomogram model, which was evaluated using ROC curve, calibration curve, and decision curve analysis.

RESULTS

Among 221 patients, 125 were diagnosed with hemorrhagic CRP, occurring at a median of 14.45 months after pelvic radiotherapy. Age (≥ 54 years), weight (< 52 kg), and radiation dose (≥ 72 Gy) were identified as risk factors. A nomogram was developed, with AUC values of 0.741 and 0.74 in the training and validation cohorts. Decision and clinical impact curves showed the model's benefit over a probability range of 0.25 to 0.85 in both sets.

CONCLUSION

In this study, we constructed and developed a nomogram for predicting hemorrhagic CRP risk. The good results in calibration curves, ROC curve analysis, and decision curves indicated that the nomogram had promise for clinical application. It may serve as a reference for radiologists in designing radiotherapy plan to help mitigate the risk of hemorrhagic CRP.

Spatial Pattern of Intraprostatic Recurrence after Definitive External-Beam Radiation Therapy for Prostate Cancer: Implications for Focal Boost to Intraprostatic Dominant Lesion

Purpose

We retrospectively investigated spatial pattern associations between primary and recurrent tumor sites after definitive external-beam radiation therapy (EBRT) for prostate cancer, using positron emission tomography/computed tomography (PET/CT) with a prostate-specific membrane antigen (PSMA)-targeted probe, 18F-FSU-880.

Methods and Materials

We used data from our prior phase 2 trial involving patients who received PET/CT with 18F-FSU-880, which was designed to evaluate the tumor detection efficacy of PSMA-PET/CT for recurrent prostate cancer. Data from patients with local intraprostatic recurrence detected by PSMA-PET/CT after definitive EBRT were retrospectively analyzed. The prostate and seminal vesicles were divided into 14 sections. Two diagnostic radiologists separately re-evaluated the intraprostatic location of the primary tumor on magnetic-resonance imaging and that of the recurrent tumor on PSMA-PET/CT, respectively, and the rate of overlap between primary and recurrent tumors was calculated. The overlap rate was defined as "the number of sections that overlapped between the primary tumor and recurrent tumor" divided by "the total number of sections of recurrent tumor". A recurrent tumor was considered to be at the same location as the primary tumor when the overlap rate was equal to or greater than 75%, and a partial overlap was defined as an overlap rate between 25 and 74%.

Results

Twelve patients had local recurrence detected by PSMA-PET/CT. The median time to diagnosis of local recurrence was 9.1 (range, 2.2-12.3) years after definitive EBRT. The recurrent tumor was detected at the same location in 25.0%, and a partial overlap was noted in 41.7%.

Conclusions

Local intraprostatic recurrence after definitive EBRT often occurs at the same site or at a partially overlapping site adjacent to the primary intraprostatic dominant lesion. Our results support the merit of focal dose-escalation for intraprostatic dominant lesions in definitive EBRT.

OLIGOPELVIS GETUG P07, a Multicenter Phase II Trial of Combined High-dose Salvage Radiotherapy and Hormone Therapy in Oligorecurrent Pelvic Node Relapses in Prostate Cancer

BACKGROUND

Oligorecurrent pelvic nodal relapse in prostatic cancer is a challenge for regional salvage treatments. Androgen depriving therapies (ADTs) are a mainstay in metastatic prostate cancer, and salvage pelvic radiotherapy may offer long ADT-free intervals for patients harboring regional nodal relapses.

OBJECTIVE

To assess the efficacy of the combination of ADT and salvage radiotherapy in men with oligorecurrent pelvic node relapses of prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

We performed an open-label, phase II trial of combined high-dose intensity-modulated radiotherapy and ADT (6 mo) in oligorecurrent (five or fewer) pelvic node relapses in prostate cancer, detected by fluorocholine positron-emission tomography computed tomography imaging.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was 2-yr progression-free survival defined as two consecutive prostate-specific antigen levels above the level at inclusion and/or clinical evidence of progression as per RECIST 1.1 and/or death from any cause.

RESULTS AND LIMITATIONS

Between August 2014 and July 2016, 67 patients were recruited in 15 centers. Half of the patients had received prior prostatic irradiation. The median age was 67.7 yr. After a median follow-up of 49.4 mo, 2- and 3-yr progression-free survival rates were 81% and 58%, respectively. Median progression-free survival was 45.3 mo. The median biochemical relapse-free survival (BRFS) was 25.9 mo. At 2 and 3 yr, the BRFS rates were 58% and 46%, respectively. Grade 2 + 2-yr genitourinary and gastrointestinal toxicities were 10% and 2%, respectively.

CONCLUSIONS

Combined high-dose salvage pelvic radiotherapy and ADT appeared to prolong tumor control in oligorecurrent pelvic node relapses in prostate cancer with limited toxicity. After 3 yr, nearly half of patients were in complete remission. Our study showed initial evidence of benefit, but a randomized trial is required to confirm this result.

PATIENT SUMMARY

In this report, we looked at the outcomes of combined high-dose salvage pelvic radiotherapy and 6-mo-long hormone therapy in oligorecurrent pelvic nodal relapse in prostatic cancer. We found that 46% of patients presenting with oligorecurrent pelvic node relapses in prostate cancer were in complete remission after 3 yr following combined treatment at the cost of limited toxicity.

Robot-assisted Cystectomy with Intracorporeal Urinary Diversion After Pelvic Irradiation for Prostate Cancer: Technique and Results from a Single High-volume Center

BACKGROUND

Radiation therapy (RT) for prostate cancer (PCa) treatment is burdened by high rates of late urinary adverse events (UAEs). The feasibility of robot-assisted cystectomy (RAC) with intracorporeal urinary diversion (ICUD) for treatment of high-grade UAEs has never been assessed.

OBJECTIVE

To report perioperative outcomes, early (≤90 d) and late (>90 d) complications among patients undergoing RAC for UAEs after RT.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively evaluated 32 patients undergoing RAC with ICUD for UAEs in a single tertiary centre.

SURGICAL PROCEDURE

Surgery was performed using a da Vinci Xi system with adaptation for the primary treatment.

MEASUREMENTS

Perioperative outcomes included estimated blood loss (EBL), operative time (OT), intraoperative complications, and length of stay (LOS). Data for early and late postoperative complications were collected using the quality criteria recommended by the European Association of Urology. Univariate logistic regressions were performed to test the effect of baseline and perioperative characteristics on early postoperative complications.

RESULTS AND LIMITATIONS

The median age-adjusted Charlson comorbidity index (ACCI) was 6 (IQR 5-7). The indication for RAC was hemorrhagic radiation cystitis in 29 cases (91%), contracted bladder in two cases (6.2%), and urinary fistula in one case (3.1%). The median EBL, OT, and LOS were 250 ml, 330 min, and 10 d, respectively. A total of 31 (97%) patients received an ileal conduit. The 90-d rate of Clavien-Dindo grade ≥IIIa complications was 28%. The late complication rate was 46% and the perioperative mortality rate was 0%. On univariate analyses, ACCI was the only parameter correlated with the risk of early complications (odds ratio 1.75, 95% confidence interval 1.05-2.9; p =  0.03). The median follow-up was 30 mo (IQR 15-40). The lack of comparison with open cystectomy represents the main limitation.

CONCLUSIONS

RAC for UAEs in patients with a history of pelvic irradiation is a feasible option in high-volume centers. The use of new technologies can help to overcome some of the technical difficulties and reduce the risk of perioperative and late complications.

PATIENT SUMMARY

We report our experience with robot-assisted surgery for removal of the bladder in the management of urinary problems after radiation therapy for prostate cancer. When performed by highly experienced surgeons, this is a feasible procedure with outcomes and early and late complication rates that are acceptable.

Long-term clinical outcomes of external beam radiation therapy for oligometastatic prostate cancer: A combination of prostate-targeted treatment and metastasis-directed therapy

OBJECTIVE

To assess the efficacy of combination of prostate-targeted treatment and metastasis-directed therapy for oligometastatic prostate cancer.

METHODS

We retrospectively evaluated the clinical outcomes of synchronously diagnosed oligometastatic prostate cancer patients treated with external beam radiation therapy for the prostate and all metastatic lesions (≤3 lesions) at Kyoto University Hospital between January 2004 and April 2019. The prescribed dose was basically ≥70 Gy for the prostate with or without whole pelvic irradiation, and ≥45 Gy for the metastatic lesions. Clinical outcomes were compared with a contemporary cohort of 55 synchronous oligometastatic prostate cancer patients treated with the standard of care.

RESULTS

In total, 16 consecutive patients with synchronous oligometastatic prostate cancer were analyzed. The median follow-up period was 7.4 years. The 8-year overall survival, prostate cancer-specific survival, biochemical failure-free, clinical failure-free and castration-resistant prostate cancer-free rates were 64.8%, 71.3%, 38.5%, 47.3% and 67.3%, respectively. No grade 3 or higher radiation-induced late toxicities occurred. Patients with prostate-targeted treatment plus metastasis-directed therapy had a significantly higher castration-resistant prostate cancer-free rate than those without prostate-targeted treatment plus metastasis-directed therapy (P = 0.00741).

CONCLUSIONS

Prostate-targeted treatment plus metastasis-directed therapy through external beam radiation therapy can result in favorable long-term disease-free and survival outcomes with acceptable morbidities among synchronous oligometastatic prostate cancer patients. Therefore, this approach may represent a promising treatment strategy for this population. Further investigation is required.

Increased risk of disease progression in younger men: Analysis of factors predicting biochemical failure and castration-resistant prostate cancer after high-dose intensity-modulated radiation therapy for nonmetastatic prostate cancer

BACKGROUND

The aim of this study was to investigate the clinical significance of the effect of age on disease control in men who received high-dose intensity-modulated radiation therapy (IMRT) for nonmetastatic prostate cancer (NMPCa).

METHODS

NMPCa patients with favorable intermediate to very high-risk features (National Comprehensive Cancer Network risk classification) treated with IMRT at our institution between September 2000 and May 2011 were analyzed retrospectively. Treatment consisted of high-dose IMRT (74-78 Gy/37-39 fractions) combined with 6 months of neoadjuvant hormonal therapy. Multivariable analysis using Fine and Gray's regression model was performed to evaluate whether age at initiation of IMRT was associated with biochemical failure (BF) and castration-resistant prostate cancer (CRPC) progression.

RESULTS

A total of 367 patients were analyzed. The median follow-up period was 8.8 years after IMRT. The 5- and 10-year BF rates were 22.1 and 31.7%, and those of CRPC rates were 4.5 and 12.6%, respectively. Multivariable analysis revealed that a younger age (cut-off: 70 years old) at the initiation of IMRT was significantly correlated with both a higher BF rate (hazard ratio: 1.691, P= 0.0064) and higher CRPC rate (hazard ratio: 2.579, P = 0.0079).

CONCLUSIONS

Younger men with NMPCa had increased risks of BF and CRPC after high-dose IMRT, and may benefit from more intensive treatments. Our findings should be further tested in prospective studies.