Pattern-Corrected Mitotic Activity Index (PMAI): A Novel Prognosticator of Oral Squamous Cell Carcinoma.

OBJECTIVE: The main aim was to assess the efficiency of the Mitotic Activity Index (MAI) and a novel index devised by us, the Pattern-Corrected Mitotic Activity Index (PMAI) in prognostication of Oral Squamous Cell Carcinoma in terms of lymph node involvement, margin, recurrence and survival status. MATERIAL AND METHOD: The study group consisted of 60 cases of histologically-proven Oral Squamous Cell Carcinoma with known status of prognostic indicators. Hematoxylin and eosin stained sections of the tumor proper were utilized for assessment of mitotic activity and pattern of invasion. The Mitotic Activity Index and Pattern-Corrected Mitotic Activity Index were then calculated and correlated with the prognosticators. RESULTS: Mitotic Activity Index was higher in patients who had better survival and low recurrence rates. Pattern-Corrected Mitotic Activity Index showed the greatest percentage increase in relation to lymph node involvement as compared to the other indices. Kaplan Meier survival analysis showed that a higher Pattern-Corrected Mitotic Activity Index ( > 1.45) was associated with poorer survival (37.19 months). CONCLUSION: Lack of significant association of the Mitotic Activity Index in relation to prognosticators could be attributed to a tumor having a migratory phenotype rather than a proliferative phenotype as seen in late-stage tumors. Late-stage tumors have more of a poorer pattern of invasion which is reflected best by Pattern-Corrected Mitotic Activity Index by correlating with poorer survival and lymph node involvement.

Oncocytes in Mucoepidermoid Carcinoma of the Palate: Diagnostic Challenges.

The origin of a salivary gland tumour is attributed to cells at various levels of differentiation which present histologically as diverse tissues and cellular patterns. Mitochondria-rich, eosinophilic oncocytes are cells commonly encountered in salivary gland neoplasms. We report a case of mucoepidermoid carcinoma (MEC) in the palate of a 43-year-old female that exhibited a prominent oncocytic component. While the parotid and submandibular glands have been reported as predominant sites for oncocytic MEC (OMEC), the palate and minor salivary glands are rare sites for occurrence. Also, most of the reported cases of OMEC have been histologically of low-grade mucoepidermoid carcinoma with large cystic spaces and good prognosis. In this article, we discuss the differential diagnosis and diagnostic workup of an MEC presenting with oncocytes.