Study of CD117 Expression on Phyllodes Tumor of Breast and Its Correlation with Histopathological Grade

Background: Accurately predicting the nature and differentiating of various grades of Phyllodes tumor, the diagnosis may vary by different pathologists1, as there is no standard interpretation of the histologic cut-point criteria and therefore. In this study, we evaluated the impact of CD117 expression on Phyllodes tumor of breast and usefulness of this marker to differentiating benign from malignant phyllodes tumors. Methods: This cross-sectional observational study was conducted in the Department of Pathology, Dhaka Medical College. The study includes mastectomy/lumpectomy specimens received from surgery and surgical oncology departments and diagnosed as phyllodes tumor histopathological. Tissue processing and staining were performed using standard protocol. Histopathological typing and grading were done according to WHO recommended criteria 2012. Immunostaining for CD117 done on all 50 cases. Toluidine blue staining was performed on CD117 immunostaining positive cases, to see presence of mast cells. Result: This study consists of 50 cases of phyllodes tumor of breast. In all the cases immunohistochemistry was done with markers CD117. Histological Grading of phyllodes tumor was done using stromal cellularity, nuclear pleomorphic, stromal overgrowth, mitotic rate, margin of tumor. Statistical analysis was done and results were compared with various available previous studies. This study showed that most of benign/low grade phyllodes tumors belonged to the age group of 35-46 years and most of malignant phyllodes tumors belonged to the age group of 30.50-47.50 malignant phyllodes tumor in this study was 40 years. Overall 44% (22 out of 50) of the cases showed positivity for CD117 in the stroma. Among them 85% cases of malignant Phyllodes tumors of breast shows stromal expression of CD117. This study shows association of CD117 expression with malignant phyllodes tumor. Epithelial CD117 positivity was found in 69.5% cases of benign/low grade Phyllodes tumors of breast. Current study also shows association of CD117 epithelial expression with benign phyllodes tumor the result of our study show strong correlation between CD117 expression and histopathological grade. Conclusion: In conclusion, we can report an association of CD117 protein expression in borderline/malignant tumors and which may be associated with worse prognosis. So we can suggest for targeted therapy for these patient group having Phyllodes Tumor with positive CD117 expression.