Editorial Comment to Nonmetastatic castration‐resistant prostate cancer treated with salvage focal brachytherapy after external beam radiotherapy

Abstract

performed for EBRT-resistant local recurrence of CRPC, and PSA levels rapidly decreased within 6 months. Of the salvage treatment options for recurrent cancer after radiotherapy, salvage RP has the highest likelihood of achieving local control. On the other hand, the risk of postoperative complications must be taken into consideration when selecting local salvage therapy. In a meta-analysis of salvage therapy for recurrent prostate cancer after radiotherapy, severe GU toxicity exceeded 21% for HIFU and RP but ranged from 4.2% to 8.1% for re-irradiation. The rate of severe GU toxicity was significantly lower for re-irradiation with high-dose rate brachytherapy, LDR brachytherapy, or SBRT than RP. Severe GI toxicity was less than 2% for all treatments. Although the evidence for re-irradiation in nonmetastatic CRPC recurrent after EBRT is limited, in this case, focal LDR brachytherapy did not result in either GU or GI side effect. Focal therapy of the prostate in patients with lowand some intermediate-risk cancer characteristics is intended to limit damage to adjacent structures leading to functional preservation without compensating for cancer control as a primary treatment. Even when salvage therapy is needed after EBRT, focal therapy may eliminate recurrent cancer and minimize treatment-related toxicity in patients who are carefully assessed using biopsy and imaging. In this case, with nonmetastatic CRPC recurrent after radiotherapy, focal LDR brachytherapy showed a good therapeutic effect in terms of PSA reduction, and no adverse effects were observed. Long-term follow-up studies in many patients are needed in future. In conclusion, focal brachytherapy may be a feasible option to reduce GU and GI side effects because of salvage therapy for recurrent cancer after radiotherapy with limited spread within the prostate. Conflict of interest