Primary retroperitoneal lymph node dissection for metastatic non-seminomatous germ cell tumours: outcomes and adjuvant chemotherapy.

OBJECTIVES: To compare the outcomes and treatment burden of primary retroperitoneal lymph node dissection (pRPLND) alone versus pRPLND + adjuvant chemotherapy (AC) in patients with pathological stage II (PSII) non-seminomatous germ cell tumours (NSGCT). PATIENTS AND METHODS: Retrospective review of the Princess Margaret Cancer Center eTestes cancer database identified patients with PSII NSGCT after pRPLND between 1995 and 2020. The primary outcome was relapse-free survival (RFS). Secondary outcomes included disease-specific survival (DSS), burden of relapse treatment, and factors associated with relapse. RESULTS: A total of 109 PSII patients were included in the study. There were 96 patients treated with pRPLND alone and 13 treated with pRPLND + AC. The median follow-up was 61 months. The 5-year RFS was 72% for the pRPLND-only group vs 92% for the pRPLND + AC group (hazard ratio [HR] 4.372, 95% confidence interval [CI] 0.59-32.36; P = 0.11). Within the pRPLND-only group the 5-year RFS differed by pN stage (pN1 = 94% vs pN2/N3 = 67%, P = 0.03). Despite a higher relapse rate within the pRPLND-only group, the DSS was similar at 5 years (98% pRPLND only vs 100% pRPLND + AC, P = 0.48). Only 24 (25%) of the patients in the pRPLND-only group required any subsequent chemotherapy. Despite achieving similar survival, the cumulative post-RPLND treatment burden was less for the pRPLND-only group than the pRPLND+AC group overall (average 1.23 vs 2.46 cycles of chemotherapy per patient in group). CONCLUSION: The majority of patients with PSII NSGCT treated with pRPLND alone do not experience a recurrence or require chemotherapy. Despite a lower relapse risk when AC is given, no difference in survival was seen but higher chemotherapy burden was entertained. AC may constitute overtreatment for most patients with PSII NSGCT treated with pRPLND.

Home-based versus supervised group exercise in men with prostate cancer on androgen deprivation therapy: A randomized controlled trial and economic analysis.

INTRODUCTION: Differences between health outcomes, participation/adoption, and cost-effectiveness of home-based (HOME) interventions and supervised group-based training (GROUP) in men with prostate cancer (PC) on androgen deprivation therapy (ADT) are currently unknown. The objective of this study was to assess the clinical efficacy, adherence, and cost-effectiveness of HOME versus GROUP in men on ADT for PC. MATERIALS AND METHODS: This was a multicentre, 2-arm non-inferiority randomized controlled trial and companion cost-effectiveness analysis. Men with PC on ADT were recruited from August 2016 to March 2020 from four Canadian centres and randomized 1:1 to GROUP or HOME. All study participants engaged in aerobic and resistance training four to five days weekly for six months. Fatigue [Functional Assessment of Cancer Therapy-Fatigue (FACT-F)] and functional endurance [6-min walk test (6MWT)] at six months were the co-primary outcomes. Secondary outcomes included quality of life, physical fitness, body composition, blood markers, sedentary behaviour, and adherence. Between-group differences in primary outcomes were compared to margins of 3 points for FACT-F and 40 m for 6MWT using a Bayesian analysis of covariance (ANCOVA). Secondary outcomes were compared with ANCOVA, Costs included Ministry of Health costs, program costs, patient out-of-pocket, and time costs. TRIAL REGISTRATION: #NCT02834416. RESULTS: Thirty-eight participants (mean [standard deviation (SD)] age, 70 [9.0] years) were enrolled (GROUP n = 20; HOME n = 18). There was an 89.8% probability that HOME was non-inferior to GROUP for both fatigue and functional endurance and a 9.5% probability that HOME reduced fatigue compared to GROUP (mean [SD] change, 12.1 [8.1] vs 3.6 [6.1]; p = 0.040) at six months. Adherence was similar among study arms. HOME was cost-saving (mean difference: -$4122) relative to GROUP. DISCUSSION: A HOME exercise intervention appears non-inferior to GROUP for fatigue and functional endurance and requires fewer resources to implement. HOME appears to ameliorate fatigue more than GROUP, but has comparable effects on other clinically relevant outcomes. Although limited by sample size and attrition, these results support further assessment of home-based programs.

A feasibility study of adaptive radiation therapy for postprostatectomy prostate cancer.

Postoperative prostate radiotherapy requires large planning target volume (PTV) margins to account for motion and deformation of the prostate bed. Adaptive radiation therapy (ART) can incorporate image-guidance data to personalize PTVs that maintain coverage while reducing toxicity. We present feasibility and dosimetry results of a prospective study of postprostatectomy ART. Twenty-one patients were treated with single-adaptation ART. Conventional treatments were delivered for fractions 1 to 6 and adapted plans for the remaining 27 fractions. Clinical target volumes (CTVs) and small bowel delineated on fraction 1 to 4 CBCT were used to generate adapted PTVs and planning organ-at-risk (OAR) volumes for adapted plans. PTV volume and OAR dose were compared between ART and conventional using Wilcoxon signed-rank tests. Weekly CBCT were used to assess the fraction of CTV covered by PTV, CTV D99, and small bowel D1cc. Clinical metrics were compared using a Student's t-test (p < 0.05 significant). Offline adaptive planning required 1.9 ± 0.4 days (mean ± SD). ART decreased mean adapted PTV volume 61 ± 37 cc and bladder wall D50 compared with conventional treatment (p < 0.01). The CTV was fully covered for 96% (97%) of fractions with ART (conventional). Reconstructing dose on weekly CBCT, a nonsignificant reduction in CTV D99 was observed with ART (94%) compared to conventional (96%). Reduced CTV D99 with ART was significantly correlated with large anterior-posterior rectal diameter on simulation CT. ART reduced the number of fractions exceeding our institution's small bowel D1c limit from 14% to 7%. This study has demonstrated the feasibility of offline ART for post-prostatectomy cancer. ART facilitates PTV volume reduction while maintaining reasonable CTV coverage and can reduce the dose to adjacent normal tissues.

A Clinical Consensus Approach to Developing a New Funding Model for Radiation Services in Ontario.

In 2021, Ontario Health (Cancer Care Ontario) introduced a quality-based procedure model for the funding of radiation treatment (RT) in Ontario. This model ties reimbursement to patient care activities, ensuring equity and transparency in funding. Over 200 RT interprofessionals (oncologists, therapists and physicists) participated on 22 expert panels to establish or identify 288 evidence-based RT protocols and 672 quality expectations (QEs) to optimally deliver RT, which eventually led to the micro-costing of all protocols. Iterative review is required to ensure updated techniques and identify evolving standards of care, thereby providing the highest quality of RT care to Ontarians.

Cost of Bladder Cancer Care: A Single-center Comparison of Radical Cystectomy and Trimodal Therapy.

INTRODUCTION: Radical cystectomy and trimodal therapy are both accepted options in the management of muscle-invasive bladder cancer. As such, we sought to evaluate the micro-level costs associated with both modalities. METHODS: All patients undergoing trimodal therapy or radical cystectomy for primary treatment of urothelial muscle-invasive bladder cancer at a single academic center between 2008 and 2012 were included. Direct costs associated with each phase of a patient's clinical course were collected from the hospital's financial department, and physician costs were calculated based on the provincial fee schedule. Costs of radiation treatments were derived from previously published literature. RESULTS: A total of 137 patients were included. The mean (±SD) patient age was 69 (±12) years. Overall, 89 (65%) patients underwent radical cystectomy and 48 (35%) were treated with trimodal therapy. The radical cystectomy group had higher rates of cT3/T4 compared to those in the trimodal therapy group (51% vs 26%, P < .001). The median cost in the treatment phase for radical cystectomy was $30,577 (IQR: $23,908-$38,837) vs $18,979 ($17,271-$23,519) for trimodal therapy (P < .001). There was no significant difference between treatment groups with respect to cost of diagnosis or workup. However, the cost of follow-up care was numerically higher for patients undergoing trimodal therapy compared to radical cystectomy ($3,096/y vs $1,974/y, P = .09). CONCLUSIONS: In appropriately selected patients with muscle-invasive bladder cancer trimodal therapy costs are not prohibitive and are lower than in radical cystectomy. With increasing follow-up time after primary treatment, the cost difference between modalities may be mitigated by the need for bladder surveillance and salvage therapy in the trimodal therapy cohort.

Symptom experiences of older adults during treatment for metastatic prostate cancer: A qualitative investigation.

INTRODUCTION: Exploring symptom experiences of older men during metastatic prostate cancer treatment can help clinicians identify unmet supportive care needs that, if addressed, could improve toxicity management and enhance patient wellbeing. Previous qualitative studies of older adults with advanced prostate cancer have focused on the psychological experience rather than the overall symptom experience. Therefore, the objective of this study was to understand the lived experience of symptoms and supportive care needs in older men undergoing treatment for metastatic prostate cancer. MATERIALS AND METHODS: Semi-structured interviews were conducted with older adults (aged 65+) who completed their first cycle of chemotherapy, androgen-axis targeted therapies, or radium-223 for metastatic castrate-resistant and sensitive prostate cancer at the Princess Margaret Cancer Centre, Toronto, Canada. Six coders worked in pairs to review interview transcripts and conduct a thematic analysis. A consensus was reached through team discussions. Topics of interest included symptom experiences, the impact of symptoms on daily life, symptom management strategies, and suggestions for external support. RESULTS: Thirty-six interviews were conducted with older adults (mean age: 76 years, 92% with metastatic castrate-resistant prostate cancer) who started chemotherapy (n = 11), androgen-axis targeted therapies (n = 19), or radium-223 (n = 6). The most common treatment-specific symptoms included: fatigue, pain, sleep disturbances, mood disturbances, and gastrointestinal symptoms. Four themes on the impact of symptoms on daily life emerged: resting more than usual, changes in mobility, changes in maintaining activities of daily living, and not feeling up to most things. It is important to note that participants who underwent chemotherapy have previously completed other lines of treatment and had more advanced disease, possibly contributing to higher prevalence of symptoms and greater impact on daily life. Four themes on symptom management strategies emerged: positive support systems, seeking help, interventions by healthcare providers, and self-management strategies. Suggestions for external support included building social support networks, improving health literacy, improving continuity of care, receiving support from healthcare providers, engaging in health-seeking behaviours, and addressing unmet supportive care needs. DISCUSSION: Exploring symptom experiences of older men with metastatic prostate cancer provides valuable insights for developing supportive care programs and improving patient care.

Long-term oncologic outcomes of low dose-rate brachytherapy compared to hypofractionated external beam radiotherapy for intermediate -risk prostate cancer.

PURPOSE: To compare the long-term oncologic outcomes of intermediate risk (IR) prostate cancer (PCa) patients treated with low dose-rate brachytherapy (LDR-BT) or moderate hypofractionated external beam radiotherapy (HF-EBRT). METHODS AND MATERIALS: Patients diagnosed with IR PCa and treated with LDR-BT or HF-EBRT between January 2005 and December 2013 were included. Brachytherapy treatment involved a transperineal implant of iodine-125 to a dose of 145 Gy to the PTV, while HF-EBRT was delivered using intensity modulated radiotherapy with 60 Gy in 20 fractions. The Phoenix ''nadir +2'' threshold was used to define biochemical relapse (BR). The cumulative incidence function (CIF) of BR and metastases was reported for each group and compared using the Gray's test to account for the competing risk of death. The Kaplan-Meier (KM) method was used to estimate overall survival (OS) and prostate cancer specific survival (PCSS). Univariate (UVA) and multivariable (MVA) analysis of the CIF of BR and metastases were performed. A 2-tailed p-value ≤ 0.05 was considered statistically significant. RESULTS: Overall, 122 and 124 patients were treated with LDR-BT and HF-EBRT respectively. Median follow-up was 95 months [interquartile range (IQR): 79-118] in the LDR-BT group and 96 months (IQR: 63-123) in the HF-EBRT group. BR was observed in 5 patients treated with LDR-BT and 34 treated with HF-EBRT. At 60 and 90 months, the CIF of BR was 0.9% and 3.5% in the LDR-BT group vs. 16.6% and 23.7% in the HF-EBRT (p < 0.001). The CIF of metastases at 90 and 108 months, was 0% and 1.6% vs. 3.4% and 9.1% in the LDR-BT and HF-EBRT groups (p = 0.003), respectively. At the last follow-up, 3 patients treated with HF-EBRT died from their cancer [PCSS of 97.5% at 8 years and none died in the LDR-BT group (p = 0.09). On UVA and MVA risk group and treatment modality were independently associated with CIF of BR. On UVA HF-EBRT and ISUP grade group 3 were associated with metastases. CONCLUSION: LDR-BT was associated with higher biochemical and metastases control in our cohort when compared to moderately HF-EBRT. In the absence of a randomized trial, LDR-BT when feasible should be offered to patients with a life expectancy of >8 years.

Impact of intrafraction changes in delivered dose of the day for prostate cancer patients treated with stereotactic body radiotherapy via MR-Linac.

Purpose: The purpose of this study is to evaluate the impact of intrafraction pelvic motion by comparing the adapted plan dose (APD) and the computed delivered dose of the day (DDOTD) for patients with prostate cancer (PCa) treated with SBRT on the MR-Linac. Methods: Twenty patients with PCa treated with MR-guided adaptive SBRT were included. A 9-field IMRT distribution was adapted based on the anatomy of the day to deliver a total prescription dose of 3000 cGy in 5 fractions to the prostate plus a 5 mm isotropic margin. Prostate, bladder, and rectum were re-contoured on the MR-image acquired during treatment delivery (MRBO). DDOTD was computed by propagating the dose from the daily adapted plan generated during treatment onto the MRBO. Results: Target coverage was met for all fractions, however, computed DDOTD was significantly less than the APD (p < 0.05). During an average treatment of 53 min, mean bladder volume increased by 116%, which led to a significant decrease in the DDOTD bladder D40% (p < 0.001). However, DDOTD to bladder 5 cc was significantly higher (p < 0.001) than APD. Rectum intrafraction changes were observed based on a volume change of -20% to 83% and presence of significant dose changes from APD to DDOTD for rectum D20% (p < 0.05) and D1cc (p < 0.0001). Conclusions: Intrafraction motion observed during prostate SBRT treatment on the MR-Linac have dosimetric impacts on both the target and organs at risk. Post-treatment computation using DDOTD may inform adaptation beyond anatomic changes in subsequent treatment fractions to best capitalize on MR-Linac technology and widen the therapeutic index of SBRT for PCa.

Extended Results and Independent Validation of a Phase 2 Trial of Metastasis-Directed Therapy for Molecularly Defined Oligometastatic Prostate Cancer.

PURPOSE: The role of metastasis-directed therapy (MDT) in molecularly defined oligorecurrent prostate cancer (PCa) remains irresolute. We present extended follow-up and an independent validation cohort of a prospective trial. METHODS AND MATERIALS: This study consists of 2 sequential single-arm phase-2 trials of patients with biochemical recurrence (prostate specific antigen [PSA] 0.4-3.0 ng/mL) and negative conventional imaging after radical prostatectomy and postoperative radiation therapy. All patients underwent [18F]DCFPyL positron emission tomography/computed tomography. Patients with molecularly defined oligorecurrent prostate cancer underwent MDT with stereotactic body radiation therapy or surgery, without androgen deprivation therapy (ADT). The primary end point was biochemical response (≥50% PSA decline from baseline). Secondary end points included PSA progression-free survival and ADT-free survival. The sample size of 37 MDT patients was determined based on a Simon's 2-stage design with biochemical response rate >20%, and this design was also applied for the subsequent independent validation cohort. RESULTS: Seventy-four patients underwent MDT: 37 each in the initial and validation cohorts. Both cohorts met the prespecified biochemical response rate and completed the planned 2-stages of accrual. For the pooled cohort, the median number of prostate specific membrane antigen positron emission tomography avid lesions was 2 and most (87%) recurrences were nodal. Sixty-four (87%) had stereotactic body radiation therapy and 10 (13%) had surgery. Median follow-up (interquartile range [IQR]) for the initial, validation and combined cohorts were 41 (35-46) months, 14 months (7-21), and 24 months (14-41), respectively. The biochemical response rates for the initial, validation and combined cohorts were 59%, 43%, and 51%, respectively. For the combined cohort, median biochemical progression-free survival was 21 months (95% confidence interval, 13-not reached), and median ADT-free survival was 45 months (95% confidence interval, 31-not reached). CONCLUSIONS: Half of patients treated with MDT for molecularly defined-only oligorecurrent prostate cancer exhibited a biochemical response. This study provides necessary and validated evidence to support randomized trials aiming to determine whether MDT (alone or with systemic therapy) can affect clinically meaningful end points.

Role of Lactate Dehydrogenase in Identifying Relapse for Patients With Stage I Testicular Cancer on Surveillance.

PURPOSE: Tumor markers alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase assume a key role in the management of testicular germ cell tumors. While alpha-fetoprotein and human chorionic gonadotropin have modest sensitivity and specificity for germ cell tumors, lactate dehydrogenase has weak sensitivity and specificity. We explored the utility of lactate dehydrogenase in identifying relapse among stage I seminomatous and nonseminomatous germ cell tumors on surveillance. MATERIALS AND METHODS: Patients with a history of stage I testicular germ cell tumors were identified from a prospectively maintained database at the Princess Margaret Cancer Centre from December 1980 to May 2021 and surveyed according to established institutional algorithm guidelines. The utility of lactate dehydrogenase elevation to independently detect germ cell tumor relapse was examined. RESULTS: Among 1,014 seminoma and 676 nonseminomatous germ cell tumor patients, 176 and 176 patients relapsed with a median time to relapse of 13.6 and 8.9 months, respectively. Imaging alone was the most common mode of relapse detection in 144 and 74 of seminoma and nonseminomatous germ cell tumor patients, respectively. Lactate dehydrogenase was elevated in 49 cases of seminoma and 38 cases of nonseminomatous germ cell tumors at relapse, but was never the sole relapse indicator. Among 350 seminoma and 311 nonseminomatous germ cell tumor patients who never relapsed, 210 and 233, respectively, had at least 1 elevated lactate dehydrogenase value. CONCLUSIONS: Lactate dehydrogenase alone did not independently contribute to early relapse detection in stage I seminoma or nonseminomatous germ cell tumor. Elevated lactate dehydrogenase values were documented in a high proportion of nonrelapsing seminoma and nonseminomatous germ cell tumor cases.