Hormonal receptor status with relation of subtypes and association of proliferation marker Ki-67 in breast cancer patients; a potential biomarker in patients with breast cancer

Background: Hormone receptor status is an important prognostic and therapeutic tool in breast cancer. The present study aimed to determine the comprehensive analysis of hormone receptor status and Ki-67 in breast cancer patients at a tertiary cancer centre. Methods: The relationship of subtypes ER+PR+, ER+PR-, HER2 subtype (Luminal HER2; ER+PR+HER2+), and HER2 enriched (ER-PR-HER2+) status with multiple variables were evaluated. The expression of Ki-67 was strongly associated with cancer proliferation and is a known indicator of prognosis and outcome. The study was carried out in Savera Cancer and Multispeciality Hospital, Patna, India. Result: This study includes a total of (n=979) breast cancer cases diagnosed at our centre, out of which (n=335; 34.22%) cases went through hormonal investigation. Luminal A (31.05%) subtype was the most prevalent, followed by triple negative (20.16%), luminal B (8.4%), and HER2-positive (20.05%). Majority of the tumours were located on right side (n=186; 55.52%), on the left (n=131; 39.1%) and bilateral (n=18; 5.37%) not significant (P <0.0003). As per ECOG performance status criteria 148 (44.17%) patients were on scale 3, 89 (26.56%) – on scale 2 and 24, 37, and 37 – on scale 0, 1 and 4 respectively statistical value (P=0.325). Remarkable finding in this study Ki-67 level was increased in >50% cases of TNBCs which was significant (P=0.05). As per AJCC staging criteria (n=205; 61.19%) cases were in stage III (locally advanced breast cancer). The value was significant (P=0.05). A total of 236 (72.39%) patients are alive with life expectancy of >24 months. Conclusion: In conclusion, this retrospective study demonstrated a high prevalence rate of triple negative breast cancer at our centre. Majority of cases were of TNBC subtypes. Another remarkable finding of this study was, in majority of triple negative cases Ki-67 level was >50%. Elevated level of Ki-67 indicated the aggressiveness of tumor types.