Moderate hypofractionated post-prostatectomy radiation therapy is feasible and well tolerated: experience from a single tertiary cancer centre

SABR tolerance after prostatectomy: pushing the boundaries of ultrahypofractionation

OBJECTIVE

To evaluate the feasibility and tolerance of ultra-hypofractionated SABR (stereotactic ablative radiation therapy) protocol following radical prostatectomy.

PATIENTS AND METHODS

We included patients undergoing adjuvant or salvage SABR between April 2019 and April 2023 targeting the surgical bed and pelvic lymph nodes up to a total dose of 36.25 Gy (7.25 Gy/fraction) and 26 Gy (5.2 Gy/fraction), respectively, in 5 fractions on alternate days with an urethra sparing protocol. Acute and late adverse effects were assessed using the CTCAE v5.0. Pearson's chi-square test for categorical variables was used to compare characteristics and possible associations among different subgroups.

RESULTS

Adjuvant radiation therapy (ART) was administered to 40 high-risk patients (detectable post-surgery PSA, Grade Group 4/5, nodal involvement, R1/R2 resection margin), while salvage radiotherapy (SRT) was delivered to 60 patients with rising PSA levels post-undetectable values. Elective nodal irradiation was performed in 57 patients, with 11 additional patients receiving a simultaneous integrated boost (total dose: 40 Gy in 5 fractions) for macroscopic nodal disease. Twenty-four high-risk patients underwent 24-months androgen deprivation therapy (ADT). Treatment was well-tolerated with minimal toxicity. The maximum grade of SABR-related toxicity observed was grade 3. Acute gastrointestinal (GI) toxicity included seven cases of grade 2 and one of grade 3, while acute genitourinary (GU) events were limited to grade 2 in eight patients. Early-late toxicity included two cases of grade 3 and seven of grade 2 for GI, and 11 cases of grade 2 for GU. No toxicity above grade 3 was reported. With a median follow-up of 24 months (6-60 months), 14 patients experienced disease recurrence.

CONCLUSIONS

Ultra-hypofractionated adjuvant/salvage SABR appears feasible and safe. Longer follow-up is needed to validate observed outcomes.

Moderate Hypofractionated Post-Prostatectomy Radiotherapy (MYSTERY) Versus Conventionally Fractionated Post-Prostatectomy Radiotherapy (COPORT) for the Patients With Localized Prostate Cancer: The Protocol of a Prospective, Randomized Trial

INTRODUCTION

A few studies have examined whether the safety and efficacy of moderate hypofractionated post-prostatectomy radiotherapy (moderate HYPORT, also called MYSTERY) are equal to those of conventionally fractionated post-prostatectomy radiotherapy (COPORT) in patients with localized prostate cancer. Therefore, this study aims to compare the safety and efficacy of MYSTERY and COPORT in patients with postoperative prostate cancer.

METHODS AND ANALYSIS

This study is a prospective, single-center, open-label, randomized controlled clinical trial. Patients with localized prostate cancer will be randomly allocated to receive COPORT (66-74 Gy at 2 Gy per fraction) or MYSTERY (57.5-65 Gy at 2.5 Gy per fraction). The primary outcomes are radiotherapy-related gastrointestinal and genitourinary adverse events. Secondary outcomes include progression-free survival, quality of life, medical expenses, and overall survival.

Evidences on the Use of Hypofractionation in Postoperative/Salvage Radiotherapy for Prostate Cancer: Systematic Review of the Literature and Recent Developments

BACKGROUND

Radical prostatectomy (RP) is one possible curative treatment for localized prostate cancer. Despite that, up to 40% of patients will later relapse. Currently, post-operative radiotherapy (PORT) courses deliver 1.8-2 Gy daily to reach a total dose ranging between 64 and 74 Gy, completed in 7-8 weeks. Several articles reported encouraging data in terms of the effectiveness and the related toxicities using hypofractionation schedules. The objective of the present systematic review was to evaluate the clinical outcomes and toxicity of the use of hypofractionation in adjuvant/salvage prostate cancer treatments.

METHODS

Medline was searched via PubMed and Scopus from inception to July 2024 to retrieve studies on hypofractionation in adjuvant/salvage prostate cancer treatments. This study was conducted under PRISMA guidelines.

RESULTS

A total of 139 articles were identified from the initial search. Subsequently, the 139 studies were reviewed by title and abstract. Ninety-five studies were excluded due to being either abstracts or articles not available in English. In the second step, the full texts of 44 studies were reviewed. Eleven studies were excluded for being reviews, study protocols, or focused on SBRT treatments. Finally, 33 studies were included in our analysis, with a total number of 4269 patients. Of the 33 selected studies, 20 were retrospective trials and 11 were phase I/II prospective trials, while 2 studies were prospective phase III trials. The follow-up ranged from 18 to 217 months. Failure-free survival, for those with the longer follow-up, ranged between 85% and 91% at 3 years, 47 and 78.6% at 5 years and 51.5% at 10 years. Genitourinary (GU) and gastrointestinal acute toxicity was mild to moderate with similar rates across the normofractionated and hypofractionated groups. Acute grade-3 GU toxicity events were unusual, occurring in less than 4% of the cases overall.

CONCLUSION

The present study is the first systematic review of the literature that includes the first two randomized phase III studies published in the literature. Hypofractionated treatment has been shown to be safe, effective, with moderate toxicity and not inferior to conventional RT, with good biochemical control rates.

Hypofractionated Post-Prostatectomy Radiotherapy in 16 Fractions: A Single-Institution Outcome

BACKGROUND

The optimal hypofractionated schedule of post-prostatectomy radiotherapy remains to be established. We evaluated treatment outcomes and toxicity of moderately hypofractionated post-prostatectomy radiotherapy in 16 daily fractions delivered with intensity-modulated radiotherapy. The treatment schedule selection was motivated by limited technology resources and was radiobiologically dose-escalated.

METHODS

One hundred consecutive M0 patients with post-prostatectomy radiotherapy were evaluated. Radiotherapy indication was adjuvant (ART) in 19%, early-salvage (eSRT) in 46% and salvage (SRT) in 35%. The dose prescription for prostate bed planning target volume was 52.8 Gy in 16 fractions of 3.3 Gy. The Common Terminology Criteria v. 4 for Adverse Events scale was used for toxicity grading.

RESULTS

The median follow-up was 61 months. Five-year biochemical recurrence-free survival (bRFS) was 78.6%, distant metastases-free survival (DMFS) was 95.7% and overall survival was 98.8%. Treatment indication (ART or eSRT vs. SRT) was the only significant factor for bRFS (HR 0.15, 95% CI 0.05-0.47, p = 0.001) and DMFS (HR 0.16, 95% CI 0.03-0.90; p = 0.038). Acute gastrointestinal (GI) toxicity grade 2 was recorded in 24%, grade 3 in 2%, acute genitourinary (GU) toxicity grade 2 in 10% of patients, and no grade 3. A cumulative rate of late GI toxicity grade ≥ 2 was observed in 9% and late GU toxicity grade ≥ 2 in 16% of patients.

CONCLUSIONS

The observed results confirmed efficacy and showed a higher than anticipated rate of early GI, late GI, and GU toxicity of post-prostatectomy radiobiologically dose-escalated hypofractionated radiotherapy in 16 daily fractions.

The Latest Data Specifically Focused on Long-Term Oncologic Prognostication for Very Old Adults with Acute Vulnerable Localized Prostate Cancer: A Nationwide Cohort Study

Purpose: Few studies have evaluated the prime treatment choice for men older than 80 years with acute vulnerable localized prostate cancer (AV-LPC). Clinicians have been deeply troubled by this near end-of-life medical choice for a very specific group of patients. We compared the oncological prognostication of very old patients with AV-LPC after they underwent either radical prostatectomy (RP) or massive-dose intensity-modulated radiotherapy (IMRT) coupled with long-term androgen deprivation therapy (ADT) over a long-term investigation. Methods: In this nationwide cohort study, we used the Taiwan Cancer Registry Database and retrieved information related to patients (aged ≥ 80 years) with AV-LPC who underwent standard RP (the RP group) or massive-dose IMRT + long-term ADT (at least 72 Gy and ADT use ≥18 months; the IMRT + ADT group). After potential confounders were controlled for using propensity score matching (PSM), we utilized the Cox proportional hazards regression to evaluate the oncologic prognostication. Results: The IMRT + ADT group had a significantly higher adjusted hazard ratio (aHR) for all-cause mortality (aHR, 2.00; 95% confidence interval [CI], 1.41−2.87) than the RP group. Analysis of the secondary outcomes revealed that compared with the RP group, the aHRs of biochemical failure, locoregional recurrence, and distant metastasis in the IMRT + ADT group were 1.77 (95% CI: 1.36−2.11, p < 0.0001), 1.12 (95% CI: 1.04−1.33, p < 0.0001), and 1.15 (95% CI: 1.06−1.71, p = 0.0311), respectively. Conclusion: RP provides more favorable oncological prognostication than IMRT in very old adults with AV-LPC.