Immunohistochemical expression of SOX10 and GATA3 in triple negative breast carcinoma and metastatic breast carcinoma.

Objective: Determine frequency of expression of SOX10 and GATA3 in TNBC and MBC. Study Design: Descriptive Cross-sectional study. Setting: Department of Histopathology, AFIP, Rawalpindi. Period: November 2021 to 2022. Methods: Study conducted on sample of 121 TNBC cases including, 12 MBC cases. Tumors of any size, grade and stage were included. Biopsies with only CIS, hormone-receptor and HER2 expression, post-chemoradiotherapy and relapsed cases were excluded. Immunohistochemistry was performed using SOX10 and GATA3 antibodies on FFPE samples. Results were analyzed, interpreted and finalized by two independent histopathologists. Data analyzed using SPSS-25 and comparison made between SOX10 and GATA3. Results: The mean patient age was 48.45±12.978 years. 38 cases were grade-2 and 83 grade-3. SOX10 was positive in 18 cases. 4 MBC cases expressed SOX10. GATA3 was positive in 99 cases. 8 MBC cases were GATA3 positive. SOX10 was negative in GATA3 positive cases. No statistical correlation was found between age, size, and stage of tumor (p>0.05). Combined SOX10/GATA3 was expressed in 117 cases. Statistical correlation was established when SOX10/GATA3 compared to increasing tumor grades (p<0.05). Conclusion: Combined SOX10 & GATA3 are useful markers detected with increased frequency in TNBC and MBC and can be utilized for diagnosis of these aggressive malignancies.