Triple Negative Breast Cancer in People of North East India: Critical Insights Gained at a Regional Cancer Centre

Abstract

Background: Breast cancer is a heterogeneous disease comprising of distinct biological subtypes with many targeted prognostic biomarkers having therapeutic implications. However, no specific targeted therapy for triple negative breast cancer has been discovered to date and hence further research is needed. Aim: The aim and objectives of the present study were to examine the prevalence of triple negative breast cancer (TNBC) in North-East India and to compare the clinicopathological parameters in two study groups defined by immunohistochemistry (IHC) -"TNBC" and "Others". Materials and Methods: We carried out a retrospective study in a cohort of 972 patients diagnosed with invasive breast carcinoma in the Department of Pathology, Dr. B. Borooah Cancer Institute, a Regional Cancer Centre for treatment and research, Guwahati, for a period of 3 years and 10 months from January 2010 to October 2013. Based on IHC findings, patients were divided into two groups -"TNBC" and "Others". All relevant clinicopathological parameters were compared in both. TNBC were defined as those that were estrogen receptor (ER), progesterone receptor (PR), and HER2/neu negative while those positive for any of these markers were defined as "Others". Results: In this study, out of total 972 cases 31.9% (310 cases) were defined as TNBC and 662 cases (68.1%) as "Others" based on IHC markers. Compared to the "Others" category, TNBC presented at an early age (mean 40 years), were associated with high grade large tumours and high rate of node positivity, IDC NOS being the most common histological subtype in TNBC. Conclusions: TNBC accounts for a significant portion of breast cancers in this part of India and commonly present at younger age and tend to be large high grade tumours.

Estrogen receptor, Progesterone receptor, and human epidermal growth factor receptor-2 status in breast cancer: A retrospective study of 5436 women from a regional cancer center in South India

“…There are several studies from the Indian subcontinent regarding either HR positivity alone or HR+[ 4 8 9 18 ] and TNBCs[ 19 20 21 22 ] with only six studies delineating HER2-positive and HR-negative status as a separate category. [ 7 10 11 21 22 23 24 ] Of the latter, only one has a relatively comparable volume of 2001 cases,[ 7 ] with 16% of HER2-positive cases which is similar to the 15% found in the present study. It is worthy of note that the percentage of HER2-positive cases in the Indian subcontinent is similar to that described in the Western literature.…”

Triple negative breast cancer: an Indian perspective

“…10 , 11 In the present study this prevalence was 43.5% of all breast cancers and this is consistent with persistently higher prevalence quoted in Indian populations and ethnic groups ( Table 9 ). 12 – 14 …”

Prevalence of triple negative breast cancer in India – systematic review and meta analysis.

“…Seventeen cross-sectional studies that involving 7,237 patients with breast cancer were included in this review (Table 1). [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Mean age of patients ranged from 43 to 55 years across studies, with a weighted average of age 50 years. Proportion of patients who were premenopausal ranged from 27% to 67% across studies, with a weighted average of 41%.…”