Incidence of regional lymph node metastases in patients with early prognostically unfavorable molecular biological breast cancer; Результаты оценки частоты поражения регионарных лимфатических узлов у больных ранним раком молочной железы прогностически неблагоприятного молекулярно-биологического типа

Objective. To study the incidence and risk factors of regional lymph node metastases in patients with early primary operable prognostically unfavorable breast cancer. Material and methods. The study included 200 patients with early (stage I and IIA) prognostically unfavorable molecular biological type of breast cancer between 2015 and 2019. Patients were divided equally into two groups: group 1 — oncoplastic breast resection or mastectomy with regional lymph node dissection at the first stage; group 2 — sentinel lymph node biopsy with urgent cytological examination was performed instead of regional lymph node dissection, and lymph node dissection was performed only in case of verified metastasis. Results. There were regional lymph node metastases in 15 (7.5%) patients. Of these, 10 (66.7%) ones had luminal B, Her2/neupositive type of breast cancer, 3 (20%) and 2 (13.3%) patients — triple negative and Her2/neu-positive breast cancer, respectively. Metastatic regional lymph node lesion was common in luminal B, Her2/neu-positive type (14.7%), in Her2/neu-positive type — 3.6%, in triple negative type — 3.8%. Analysis of relationship between the incidence of regional lymph node lesion on primary tumor dimension, malignancy grade, BRCA1, BRCA2 and CHEK2 gene mutations, as well as lymphovascular invasion in tumor found no significant differences. Conclusion. Luminal B, Her2/neu-positive breast cancer has the highest aggressiveness regarding regional metastasis (14.7%) among prognostically unfavorable types of breast cancer in stage I—IIA patients. © 2025 Elsevier B.V., All rights reserved.