Data Analysis Comparing Intraoral Lymphomas and Minor Salivary Gland Carcinomas

Objectives: The intent of this study is to compare relative incidence of lymphoma and minor salivary gland carcinomas of the hard and soft palate over two decades, and correlation with clinical impression of contributor. Further, to determine any change in ratio of lymphoma to salivary gland carcinoma over a seven decade period of time.
Methods: Records were extracted from the VCU Oral Pathology biopsy service database containing 168,095 cases. Variables of interest queried include clinical impression, histological diagnosis, location,biopsy date, contributor’s practice type, patient’s sex, DOB and age. Two data sets were produced using biopsies from 1990-1999 and from 2000-2009. Histological diagnosis included lymphoma, lymphoproliferative disease, adenocarinoma, mucoepidermoid carcinoma and adenoid cystic carcinoma.
Results: The data set contained 496 patient records representing 138 lymphomas and 358 minor salivary gland tumors. Bivariate analysis of the potential predictor variables revealed Age at Biopsy, Clinical Impression and Location to be significant. There was no dramatic change in ratio of lymphoma vs salivary gland carcinoma over the two decade comparison. However, a marked trend in the mean predicted proportions, from this model, of lymphoma and minor salivary gland carcinomas demonstrates a steady increase in the proportion of lymphomas.
Conclusions: From a series of 496 intraoral biopsies, representing 354 minor salivary gland tumors and 136 lymphomas, the mean predicted proportion of salivary gland tumors vs mean predicted proportion of lymphomas showed a steady increase in the percentage of lymphomas.