Role Of Cytokeratin 5/6 in Differentiation Between Benign and Malignant Breast Tumors

Abstract

This is a hospital based analytical retrospective case control study conducted at Radiation and Isotope Center (RICK) and Ibrahim Malik hospital (Khartoum State), and Sudan university of science and technology - college of medical laboratory science, during the period from April to August 2016. The study aimed to investigate the role of CK 5/6 in differentiation between benign and malignant breast tumors, using immunohistochemistry. Forty paraffin blocks were collected from patients previously diagnosed as breast tumor, 30 (75%) of them were malignant samples and 10 (25%) of them were benign samples. The paraffin blocks were cut by rotary microtome, then stained by immunohistochemistry method (Avidin biotin technique). The data obtained was analyzed using SPSS program version 20. Frequencies mean and Chi-square test values were calculated. The age of patients ranged between 18 to 80 years with mean age of 46 years. The study revealed that most patients were more than 40 years representing 27 (76.5%) and the remaining 13 (32.5%) were less than 40 years. The histopathological diagnosis of patients revealed invasive ductal carcinoma in 26 (65%) samples, medullary carcinoma in 1 (2.5%) sample, invasive lobular carcinoma in 1 (2.5%) sample, invasive medullary carcinoma in 1 (2.5%) sample, invasive micropapillary carcinoma in 1 (2.5%) sample, fibroadenoma in 7 (17.5%) samples, fibrocytic changes in 2 (5%) samples, mastitis in 1 (2.5%) sample. The grade of tumors showed grade I in 1 (2.5%) sample, grade II in 7 (17.5%) samples, grade III in 16 (40%) samples, and not graded in 6 (15%) samples. Positive expression of CK 5/6 was found in (9/30) in malignant samples and (21/30) samples showed negative expression, while all benign samples (10/10) showed positive expression of CK 5/6, this result showed significant association of CK 5/6 expression and benign breast tumors (P. value = 0.000). The study concluded that positive expression of CK 5/6 was associated with benign tumors of breast.