Mucoepidermoid carcinoma: A comparative analysis of histological grading systems

Abstract

: Salivary gland carcinomas comprise of only 3-5% of all head and neck malignancies. Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumor. The morphologic diversity of MEC can pose diagnostic challenges hence, various histological grading systems have been proposed based on the quantitative and qualitative analysis. This proves to be greatly consequential in the management and prognosis of patients with MEC.To compare histologic grading methods in MEC of major & minor salivary glands.20 histopathologically diagnosed cases of MEC (10 each major & minor salivary gland) will be analysed using following methods: Qualitative Method: 1) Modified Healey 2) Memorial Sloan-Kettering Cancer Center method. Quantitative method: 1) Armed force Institute of Pathology (AFIP) 2) Brandwein method Histological findings were evaluated. In our study AFIP grading system, 50% Cases were classified as low grade, 35% as intermediate grade and 15% as high graded. According to Brandwein grading system20% of cases were categorized as low, 35% cases as intermediate, 45% cases as high grade MEC. Modified Healey grading system of MEC showed 50%, 40%, 10% cases as low, intermediate and high grade MEC respectively. MSKCC grading system revealed as 55%, 30% and 15% cases as low, intermediate and high grade MEC respectively. Our finding indicated that MSKCC grading system was the most favourable histological grading system as percentage of agreement found to be 85%.Careful microscopic examination is the most important parameter in the grading of MEC. This meticulous microscopic examination emerges as the cornerstone in grading MEC. Both MSKCC and Modified Healey grading methods exhibits effectiveness in evaluating MEC. Our finding indicated that Memorial Slon Kettering Cancer Center (MSKCC) was the most favourable histological grading system as percentage of agreement found to be 85%. However, further longer studies are imperative to substantiate this finding and for establish of universally accepted grading system for Mucoepidermoid carcinoma.