Despite advances in the early diagnosis of breast cancer (BC), the identification of locally advanced forms continues to be relevant. This is a complex category of patients whose treatment includes the complex use of various methods with significant medical and economic costs, long-term treatment and rehabilitation. A particular difficulty is the treatment in cases of progression of locally advanced forms. Patients with locally advanced BC require a multidisciplinary approach. In the absence of an effect after neoadjuvant drug treatment and the impossibility of performing surgical intervention, patients are treated with induction radiation therapy. The article describes the features of induction radiation therapy in the treatment of progression of primary inoperable BC in a specific clinical example. In case of recurrence of triple negative type of BC, the patient underwent various drug treatment regimens with the inclusion of immunotherapy. Due to the lack of effect from 3 lines of systemic drug treatment, it was decided to conduct radiation therapy. In connection with the identified carrier of a mutation in the BRCA1 gene, targeted therapy with PARP inhibitors was prescribed. Two months after radiation therapy and 1 month after the start of targeted therapy, the patient showed complete resorption of the tumor conglomerate on the anterior chest wall. The use of conformal radiation therapy in case of recurrence of the disease and the absence of the effect of systemic treatment made it possible to completely resorb an exophytic tumor with ulceration and achieve remission within the next 6 months.