Prognostic Factors and Survival Analysis of Patients with Triple Negative Breast Cancer - A Retrospective Study

Abstract

Introduction: Breast cancer accounts for the highest number of cases of all the cancers in females worldwide including India where it has an increasing trend of 27. 7 % with 162,468 newly detected cases and 87,090 deaths (11.1 % of the total cancer-related deaths) in India as per Global cancer statistics (GLOBOCAN) 2018, The triple-negative breast cancers (TNBC) are considered as the most malignant subtypes with a multitude of distinctive hostile clinicopathological characteristics, like the age of onset and large size of the tumour, higher tumour grade, the early peak of recurrence, and a worse 5-year overall survival rate. Materials and Methods: This single-institution retrospective study included a TNBC patient cohort determined as per histopathological guideline according to WHO classification and histological grade of tumours based on Nottingham histological score which was treated in the Department of Radiation Oncology, Kurnool Medical College, Kurnool between January 2023 and December 2023. Results: 33 patients were eligible for this study as non-metastatic TNBC. Of the total 325 cases of breast cancer cases reported in the study period, non-metastatic TBNC came around 20 % (67 cases). The median age at diagnosis was 51.36 ± 11.393 (range, 30.0-80.0 years). Patient characteristics are shown in Table 1. Only 6 % had a family history of breast cancer. The majority of the patients were premenopausal (53.75 %). Most of the patients had ductal carcinoma (92. 5%) followed by metaplastic (4.5 %) and medullary carcinoma (3.0 %). Clinically, majority of the patients were of T2 stage (41.9 %) and N1 stage (59.6 %). Composite clinical stage 2 dominated (49.5 %) followed by stage 3 (46.3 %) and stage 1 (4.2 %). 62.8 % were of p T2 stage and 36 % idiopathic neutropenia (inp) N0 stage which constitutes major portion. Pathological nodal positivity was seen in 46.3 %. Clinically and pathologically tumour stage and the nodal stage was proportionate on cross tab analysis. Nodal density ≤ 0.05 was present in 65.7 % of the patients, whereas 34.3 % of patients had nodal density ≥ 0.05. Lymphovascular invasion was positive in 22.4 % (N = 7) and was absent in 77.6 % of the patients. Margin positivity was present in 4 patients (11.9 %). Conclusion: Triple-negative breast cancer is a heterogeneous disease and poses a major challenge and uphill task during treatment as these tenacious tumours have aggressive tumour biology. In the absence of biomarker-based therapeutic methods, targeted treatments neglect one significant desired outcome aimed at minimizing recurrences and improving survival in this patient population. There are many developments in treatments for metastatic triple- negative breast cancer, such as poly-ADP ribose polymerase (PARP) inhibitors, EGFR targeted therapies and tailor-made therapies but in non-metastatic breast cancer there is a dearth of adequacy in available therapeutics as treatment is still heavily dependent on available chemotherapeutic regimens.