P.V. Bulychkin, S.I. Tkachev, M.V. Chernykh, V.B. Matveev, A.V. Klimov, S.N. Berdnikov
N.N. Blokhin National Medical Research Center of Oncology, Moscow
Bulychkin P.V. — PhD (Medicine), Senior Researcher of the Radiotherapy Department
24 Kashirskoe shosse, 115478 Moscow, Russian Federation, e-mail: petrbulychkin@gmail.com, ORCID ID: 0000-0003-3947-1267
Abstract. One of the radical treatments for patients with prostate cancer (PCa) is radical prostatectomy (RP). However, a part of patients have a biochemical recurrence after surgical treatment. In this case, using a positron emission tomography / computed tomography with 68-Gallium-PSMA/18-Fluorine-PSMA, it is possible to identify the metastatic process at an early stage and detect the disease development within the oligometastatic condition.
Objective — to improve the results of combined treatment of patients with locoregional recurrences and oligometastases after RP, by improving radiation therapy techniques.
Material and methods. The retrospective and prospective, single-center cohort study included patients with local / regional / locoregional recurrence of prostate cancer and a “low” metastatic burden after RP, which was defined as the presence of metastatic lesions in the retroperitoneal lymph nodes and/or the presence of distant oligometastases (≤ 5). All patients underwent combined hormone-radiation therapy using two original radiation therapy methods developed at the N.N. Blokhin NMRCO. The primary endpoint was a 3-year progression-free survival (PFS). The secondary endpoint was the period without specific treatment.
Results. From 06/2014 to 09/2024, 53 patients were treated with a median follow-up of 50 (7–129) months. The 3- and 5-year PFS rates were 70% and 46%, accordingly. The median time without specific treatment was 17 (0–93) months.
Conclusions. The study results demonstrate that the proposed paradigm of maximally intensified combined treatment for patients with locoregional recurrences of prostate cancer and a “low” metastatic burden may be a potential treatment option for this category of patients, which allows for the abandonment of palliative and economically burdensome hormonal / chemohormonal therapy due to the achievement of long-term disease remission.
Key words: prostate cancer, salvage radiation therapy, biochemical recurrence, local recurrence, PSA, oligometastases.