Dr. Sci. (Med.), Head of the 1st Oncology Department (Oncomammology and Reconstructive Plastic Surgery), Professor, Department of Oncology, Radiotherapy, and Reconstructive Surgery, N.V. Sklifosovsky Institute of Clinical Medicine
д.м.н., зав. 1-м онкологическим отделением (онкомаммологии и реконструктивно-пластической хирургии), профессор кафедры онкологии, радиотерапии и реконструктивной хирургии ИКМ им. Н.В. Склифосовского
Postgraduate Student, Department of Oncology, Radiotherapy, and Reconstructive Surgery, N.V. Sklifosovsky Institute of Clinical Medicine
аспирантка кафедры онкологии, радиотерапии и реконструктивной хирургии ИКМ им. Н.В. Склифосовского
Dr. Sci. (Med.), Chief Physician, Professor, Department of Oncology, Radiotherapy, and Reconstructive Surgery, N N.V. Sklifosovsky Institute of Clinical Medicine
д.м.н., главный врач, профессор кафедры онкологии, радиотерапии и реконструктивной хирургии ИКМ им. Н.В. Склифосовского
Dr. Sci. (Med.), Professor, Academician of the Russian Academy of Sciences, Head of the Department of Oncology, Radiotherapy, and Plastic Surgery, N.V. Sklifosovsky Institute of Clinical Medicine, Director of the L.L. Levshin Institute
д.м.н., профессор, академик РАН, зав. кафедрой онкологии, радиотерапии и пластической хирургии ИКМ им. Н.В. Склифосовского, директор Института кластерной онкологии им. проф. Л.Л. Левшина
Cand. Sci. (Med.), Head of Chemotherapy Department No. 2, Day Hospital for Antitumor Drug Therapy No. 2
зав. химиотерапевтическим отделением № 2, дневным стационаром противоопухолевой лекарственной терапии № 2
4th-year student, N.V. Sklifosovsky Institute of Clinical Medicine
студентка 4-го курса Института клинической медицины им. Н.В. Склифосовского
Background: Breast cancer is characterized by pronounced molecular heterogeneity, which determines differences in prognosis, sensitivity to therapy, and the potential for breast-preserving and reconstructive interventions. The most aggressive course is observed in triple-negative and Her2/neu-positive breast cancer types, which justifies the need for a comprehensive assessment of factors influencing the effectiveness of neoadjuvant treatment and the choice of surgical approach.
Objective: Evaluation of the impact of immunohistochemical (IHC) subtype and neoadjuvant drug treatment regimens on clinical and pathological response, as well as their relationship with the choice of surgical intervention in patients with prognostically unfavorable forms of breast cancer (BC).
Materials and methods: A retrospective study of 500 patients with stage II–III breast cancer was conducted. IHC types, neoadjuvant therapy regimens, clinical response, residual cancer burden (RCB), and the nature of surgical treatment were analyzed. Nonparametric statistical methods and categorical data analysis were used.
Results: Statistically significant differences were found between the subtypes in terms of Ki-67 levels, differentiation grade, and disease stage (p< 0.05). The rate of complete pathological response (RCB-0) was highest in the Her2/neu-positive subtype (70.2%) and lower in the triple-negative and luminal B, Her2/neu-positive subtypes (46.9 and 46.5%, respectively). Clinical response did not differ between the groups (p=0.312). The type of surgical intervention did not achieve statistically significant differences between the groups (p=0.066), but a tendency towards differences was noted. Differences were also found in the choice of specific oncoplastic and reconstructive techniques (p=0.021).
Conclusion: IHC subtype is a significant predictor of pathological response, but does not independently influence the choice of the extent of surgical intervention, which is determined primarily by clinical and anatomical factors. The obtained data substantiate the need to consider RCB when assessing therapy efficacy and planning treatment.