Protocol-based CT-guided brachytherapy for patients with prostate cancer and previous rectal extirpation—a curative approach

Abstract

Abstract Objective There are numerous curative treatment possibilities for prostate cancer. In patients who have undergone rectal extirpation for rectal cancer treatment, curative options are limited due to anatomic changes and previous irradiation of the pelvis. In this analysis, we validate the feasibility of CT-guided transperineal interstitial brachytherapy for this specific scenario. Patients and methods We analyzed the treatment procedures and outcomes of 5 patients with metachronic nonmetastatic prostate cancer. Ultrasound-guided brachytherapy was not possible in any of the patients. Of these 5 patients, 3 were treated for prostate cancer using temporary brachytherapy with Ir-192 only, and 2 were treated with external-beam radiation therapy and temporary brachytherapy as a boost. CT-guided brachytherapy was performed in all patients. We analyzed the feasibility, efficacy, treatment-related toxicity, and quality of life (EORTC-30, IEFF, IPSS, and ICIQ questionnaires) of the treatments. Results Median follow-up was 35 months. Two out of five patients received boost irradiation (HDR 2 × 9 Gy, PDR 30 Gy). Three out of five patients were treated with PDR brachytherapy in two sessions up to a total dose of 60 Gy. Dosimetric parameters were documented as median values as follows: V100 94.7% (94.5–98.4%), D2bladder 64.3% (50.9–78.3%), D10urethra 131.05% (123.2%–141.2%), and D30urethra 122.45% (116.2%–129.5%). At the time of analysis, no biochemical recurrence had been documented. Furthermore, neither early nor late side effects exceeding CTCAE grade 2 were documented. Conclusion CT-guided transperineal brachytherapy of the prostate in patients with previous rectal surgery and radiation therapy is safe and represents a possible curative treatment option. Brachytherapy can be considered for patients with metachronic prostate cancer in this specific scenario, albeit preferably in experienced high-volume centers.