Comparative Study of Clinicopathologic Features of Apocrine Carcinoma of Breast with Invasive Breast Carcinoma of No Special Type- A Tertiary Care Centre Experience

Abstract

Introduction: Apocrine Carcinoma (AC) of breast is a rare breast cancer comprising only 0.3-1.0% of all breast cancers. Microscopically, Invasive Duct Carcinoma of No Special Type (IDC-NST) and AC have similar architecture, but they differ in cell morphology. Immunohistochemistry for both the tumour types is also different. Aim: This study was undertaken to know the incidence of AC and analyse them with respect to different clinicopathological features and compare them with that of IDC-NST. Materials and Methods: This was an observational study conducted in Department of Pathology, Veer Surendra Sai Institute of Medical Science and Research, Burla from March 2010 to February 2019. Patients diagnosed as invasive breast carcinoma were taken as study group. Breast cancer in male patients and female patients taking neoadjuvant chemotherapy were excluded from study group. Clinical features, pathological features and immunohistochemical findings of IDC-NST and AC were studied and statistical data were analysed by SPSS version 23.0 for windows. Comparison of data was done by using Pearson’s Chi-square test. Results having p-value <0.05 were accepted as significant. Results: During the 10 years, 05 cases of AC and 560 cases of IDC-NST were found. Mean age of presentation of AC was 59.5 years and that of IDC-NST was 50.4 years. Most cases of AC and IDC-NST presented with breast lump of size >5 cm. Low grade (grade 1) carcinoma was seen in 20% of AC. Immunohistochemistry showed 3 (60%) cases of AC as triple negative, whereas 213 (38.2%) of IDC-NST were triple negative. All the cases of AC were Gross Cystic Disease Fluid Protein (GCDFP-15) and CK-7 positive. Conclusion: AC is a rare category of breast cancer. Although prognosis of AC and IDC are almost similar, correct diagnosis of AC is important as antiandrogenic therapy can be given to Androgen Receptor (AR) positive AC cases.