Histological and Immuno-Histochemical Evaluation of Mast Cells in a Retrospective Cross – Sectional Study of Breast Tumour Patients

Background: Breast tumours are the most important lesion of the female breast, the most common invasive cancer in women and second leading cause of cancer death in women after lung cancer. This is becoming most common and more deadly with over 200,000 cases per year in Nigeria and Africa in general. Methods: A retrospective cross-sectional study was carried out from 2017 to 2023. One hundred and fifty (150) archived breast tumour tissue samples were retrieved from the histopathology Laboratory of Madonna University Teaching, Hospital, Elele. Patients’ data were retrieved from the histopathology reports. Tissue blocks were re-embedded in fresh paraffin wax and 4µ thick serial sections were cut and stained accordingly. Results: Benign tumours showed increased number of mast cells and mast cell membrane permeability making it hyper-chromatic with hypertrophy specifically having the highest immune reactivity count. Malignant tumours had decreased number of mast cells surrounding the periphery of the tumour with lobular carcinoma specifically showing the lowest number of mast cell per high power field. Patients’ ages at presentation ranged from 15 to 64 and breast tumour was highest between the ages of 25 ≤34. Conclusion: The evaluation and mast cell expression pattern in breast tumours maintained different activities of mast cells in benign and malignant tumours and could serve as a positive prognostic indicator for patient’s stratification and specific treatment. However, further studies on immune-histochemical evaluation of mast cells in breast tumours should be extended to frozen sections.