Background: Mucins are complex carbohydrates secreted by different types of epithelial cells and glandular tissues of gastrointestinal tract. Mucins are mainly of two types- Neutral and Acidic. Pathological expression of mucins has been implicated in cancer development and progression.

Objectives

• To know the mucin distribution pattern in normal and malignant lesions of the colon and rectum.
• To differentiate the types of mucin secreted in normal and malignant lesions of the colon and rectum, based on the colour intensity.

Methodology: The present study was conducted on twenty five specimens of each normal and carcinoma of colon and rectum, which were collected from surgically resected, small biopsy specimens and post-mortem specimens received in the Department of Pathology, MMC & RI. Normal colorectal specimens were used as controls with colorectal carcinoma as tests.

Routine H&E and special stains such as PAS, PAS-Diastase, combined AB-PAS were performed.

Results: Results were tabulated  according  to  colour  intensity into  different  grades  ranging from  +  to  ++++. Regarding mucin histochemistry of normal colon - “mixture” of mucins were observed with predominance of “neutral” and “sulphomucins”. In colon adeno-carcinoma “sialomucins” were seen predominant than neutral and sulphomucins.

Conclusion: Mucin histochemistry is a valuable and cost-effective tool for determining the types of mucins which is one of the important prognostic marker in early detection of colorectal cancers.

Keywords: Colorectum, adenocarcinomas, mucins, histochemistry, special stain.

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Dr Roopashree G

Postgraduate Student, Department of Pathology, Mysore Medical College and Research Centre, Mysore