Metastasis-directed therapy for metachronous metastases of prostate cancer

Background. The main method of treatment of metastatic hormone-sensitive prostate cancer (mHSPC) is drug therapy (hormone therapy, chemotherapy). However, a special category of patients with oligometastatic lesions can be identified in which addition of local treatment of metachronous metastases can be considered.

Aim. To improve the results of treatment of patients with mHSPC.

Materials and methods. The prospective single-center cohort study included patients with metachronous mHSPC oligometastases (≤5) in the bones and nonregional lymph who were treated at the N.N. Blokhin National Medical Research Center of Oncology. Metastasis-directed therapy consisted of stereotactic body radiation therapy with total dose of 27–35 Gy (3–5 fractions). The primary endpoint was 6-month recurrence-free survival (RFS), the secondary endpoints were median RFS and local control.

Results. Between 2017 and 2023, 38 patients were treated with median follow-up of 18 (3–79) months. Six-month RFS was 84.2 %, median RFS was 15 (3–62) months, local control was achieved in all 100 % of patients.

Conclusion. Stereotactic body radiation therapy is a promising approach to the treatment of patients with metachronous mHSPC oligometastases. However, determination of the true place and role of this method in treatment schemes for patients of this category requires further studies including randomized phase III trials.

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