C-Kit (CD-117) expression in malignant phyllodes tumors of breast

Backgroud: Malignant Phyllodes tumor (MPT) is a fibro epithelial neoplasm of breast, and has an age adjusted incidence rate of 3.1 per one million women. The recurrence rate of MPT reported by various studies varies from 356%, and 27% according to WHO, usually detected within 3 years.Objective: The objective of this study is to, “Determine the frequency and grading of c-kit (CD-117) immunohistochemical (IHC) expression in 'malignant Phyllodes tumors' of breast in patients presenting to tertiary care hospital” st st Materials & Methods: This was a descriptive, cross sectional study, conducted from 1 July 2010 to 31 December 2010 in Histopathology, Pathology and Microbiology departments of, Aga Khan University Hospital (AKUH), Karachi Forty-three consecutive cases of biopsy proven malignant Phyllodes tumor of breast were stained using ckit antibody by immunohistochemistry. Grading of ckit immunohistochemical expression was assessed, in neoplastic stromal cells.Results: Out of these 53.5% (23) were grades 1, 23.3% (10) were grade 2 and 23.3% (10) were grade 3. Further categorizing these, 46.5 % (20) were positive and 53.5% (23) were negative for ckit.Conclusion: Results of our study showed that 46.55 % of cases of malignant Phyllodes tumor showed positive staining for ckit. Twenty three% of our cases showed strong staining for ckit and thus are the most likely candidates for targeted treatment against this gene by drugs such as Imatinib mesylate.