Laminin 332: A New Hope as a Prognostic Marker in Triple Negative Breast Carcinomas

Introduction: Laminin expression is supposed to be associated with a number of invasive carcinomas, particularly squamous cell carcinoma of the oral cavity and uterine cervix. Overexpression of laminin is seen in a high proportion of triple negative breast carcinomas, which is associated with an unfavourable clinicopathological state and poor prognosis.

Aim: To evaluate the role of laminin 332 expression as a prognostic marker in triple negative breast carcinomas.

Materials and Methods: This prospective study was conducted in the Department of Pathology, SCB Medical College, Cuttack, Odisha, India, during the period from January 2018 to December 2020. Total number of histologically diagnosed breast carcinoma cases reported was 322, over a span of two years. Out of which, 59 cases showed Estrogen Receptor (ER), Progesterone Receptor (PR) and Human Epidermal growth Receptor 2 neu (HER2neu) negativity. These triple negative breast carcinoma cases were further subjected to laminin immunostaining, excluding three due to lack of sufficient tissue. The results were interpreted and represented in a tabular manner taking into account the clinicopathological manifestation, tumour grading and correlation with laminin expression.

Results: Only the 56 triple negative breast carcinomas were subjected to laminin immunostaining. Majority 50 (89.28%) were elderly patients above 50 years of age. Also, a higher proportion of cases i.e. 36 (64.29%) were grade 3 tumours. Histopathologically, 55 (98.21%) cases were Infiltrating Duct Carcinomas (IDC). Lymph node metastasis and lymphovascular invasion were found in 32 (57.14%) and in 36 (64.29%) cases, respectively. Laminin was strongly positive in those with higher grade (grade-3) tumours 24 (66.67%), those with lymph node involvement 17 (53.12%) and those showing lymphovascular invasions 28 (77.78%).

Conclusion: Laminin immunostaining is an important prognostic marker in a number of epithelial malignancies. The present study was intended to predict the role of laminin as a prognostic biomarker in the triple negative breast carcinoma cases