Key Points
• Source: Frontiers in Oncology
• Conclusion/Relevance: “Local ablative radiation therapy directed to progressive metastasis is a non-invasive, well tolerated treatment with efficacy on prolonging clinical benefit of systemic therapies with ARTT [androgen receptor-targeted therapy]. Patients who underwent RT>6 months from the start of ARTT presented a statistically better OS and PFS compared with patients who underwent radiotherapy <6 months from the start of ARTT.”
• In the current study, researchers investigated whether radiotherapy in the form of metastatic-directed therapy (MDT) involving oligo-progressive sites in metastatic castration-resistant prostate cancer (mCRPC) patients during treatment with androgen receptor-targeted therapy (ARTT) could result in control resistant lesions, thus lengthening the application of ARTT.
• The Italian researchers found that median OS was 32.5 months, 1 and 2-year OS were 71.6% and 64.1%, respectively, and 7 patients continued with ARTT until the last follow-up. Importantly, RT was well tolerated, with no toxicities and good pain control.
• Limitations of the current study include its small sample size and retrospective design, which precluded elucidating a definitive role in determining how MDT improved survival outcomes.
• “Heterogeneity of radiotherapy regimes involving a different intent (ablative and palliative) is another limitation. Despite the emerging role of advanced imaging (e.g., F-18 Fluor Choline/PSMA PET-CT scans and multiparametric MRI), CT and bone scans still represent the standard of care in clinical practice, and they are used in most clinical trials for ARTTs. Our approach using advanced imaging for detection and follow-up of oligoprogressive treated lesions may have influenced treatments timing and furthermore survival outcomes,” wrote the authors.
• The authors recommended that future studies validate the findings of this study, and elucidate other prognostic factors to select oligoprogressive patients who may derive benefit from a local treatment without interruption of ARTT vs those who need an immediate change of therapeutic strategy.