Aqueous beetroot dye as an alternative to haematoxylin and eosin in the diagnosis of breast tumours
Breast tumours are heterogeneous diseases that result from changes in the cells and connective tissues of the breast. Different histological and histochemical stains have been employed to aid in the detection of these changes in routine diagnosis. The aim of this study was to assess the usefulness of aqueous beetroot dye in the histochemical staining of breast tumours. Thirty breast tumour blocks from the Histopathology Laboratory of the University of Calabar Teaching Hospital, Calabar were retrieved, sectioned and stained with Cole’s haematoxylin and eosin and aqueous beetroot. The histological staining and 3-D image characteristics were analysed. The histological types of breast tumours were 7(23.3%) benign, of which 5(16.7%) were grade II benign lesion, 1(3.3%) was fibrocystic disease and 1(3.3%) was fibroadenoma. Among the 23(76.7%) malignant tumours, 15(56.7%) were grade 3, 3(10%) were B4 carcinomas and 3(10%) were B5 types. The sections stained with the red beetroot dye gave distinct metachromatic staining of the connective tissues of the cell membranes of the epithelial cells and other connective tissue cells, cytoskeleton, cytoplasm, basement membrane, and collagen fibres of the stroma in shades of green, purple, and black. The histological staining and 3-D image characteristics of the beetroot-stained benign and malignant tumours were similar to the haematoxylin and eosin-stained counterparts in terms of nuclear, cytoplasmic and connective tissue staining, 3-D surface plot features, and histological details (χ2=1.200; p=0.549). This finding has shown that betalain pigments in beetroot dye gave good metachromatic staining of epithelial and connective tissue changes in breast tumours. Beetroot dye and 3-D surface plots when combined can serve as a cost effective, health and environment-friendly alternative staining method to routine haematoxylin and eosin in diagnosis of breast tumours in low resource areas.