Multimodal therapy for oligometastatic prostate cancer: results from a single-centre study

Abstract

Introduction. In recent years, interest in the use of radical prostatectomy (RPE) as one of the components of a multimodal approach in patients with lymphogenous disseminated and metastatic prostate cancer (PCa) has grown significantly. At the same time, the dearth of large randomized trials does not make it possible to use this technique in wide clinical practice outside of clinical trials.Purpose of the study. To evaluate the effectiveness of multimodal therapy using combined chemo-hormonal, surgical and radiation therapy in patients with primary oligometastatic hormone-sensitive PCa.Material and methods. The study included 48 patients with primary oligometastatic prostate cancer who received combination treatment within the internal one-research-center protocol. At the first stage, all patients underwent combined drug therapy with docetaxel (75 mg/m2 intravenously every 3 weeks for 6 courses) and degarelix. Patients who had a decrease in PSA level ≤ 2 ng/ml and registered stabilization of the disease according to radiological examination were treated surgically through RPE with extended pelvic and retroperitoneal lymph node dissection. Radiation therapy was performed only in patients with the presence of bone lesions at a dose of 50-70 Gy to the location of bone metastases in the stage 3 plan of combined multimodal therapy.Results. PCa biochemical relapse was verified in 27 (56.3%) patients during the median follow-up of 10 months. The average time to PSA increase was 9.0 ± 5.7 months (from 1 to 24 months), median — 7 months, Six-month PSA relapse-free survival (PSA-RFS) was 61.2 ± 7.5%; 1-year PSA-RFS — 38.0 ± 8.6%. The average duration before the initiation of hormonal therapy was 12 ± 6.1 months (from 3 to 27 months), median: 10 months. Six-month survival before the drug administration was 72.6 ± 6.8%; twelve-month survival: 40.9 ± 8.7%. About 40% of patients with oligometastatic PCa had no signs of progression and did not receive any other drug therapy for 12 months after completion of protocol treatment.Conclusions. Analysis of the study results demonstrates satisfactory oncological outcomes of the studied treatment option in patients with newly diagnosed oligometastatic hormone-sensitive PCa, as well as a low likelihood of side effects and complications. Nevertheless, it is necessary to continue conducting larger and more structured randomized trials to determine the possibility of applying this therapeutic approach in clinical practice.