Oral Melanocarcinoma: A Clinical Diagnostic Conundrum

Objectives: The purpose of this study is to compare clinical and histological diagnoses of suspected intraoral melanocarcinomas. Is there a discernable difference in accuracy of clinical diagnosis by specialists?
Methods: Records were obtained from VCU Oral Pathology biopsy database containing 168,095 cases. Cases of specific interest were biopsies with a clinical impression of "melanoma" (N=200). In addition, specimens that received microscopic diagnosis of melanocarcinoma were included (N=13) yielding data subset of 209 records, (four cases were included in both subsets.) Variables included in data subset were clinical impression of submitting doctor, diagnosis by oral pathologist, location, patient's sex, age, and de-identified patient accession number. Analyses included: summary, statistics, percentages within groups and repeated measures logistical regression.
Results: Data subset contained 209 records, 126 (60%) female, mean age at time of biopsy was 50.6 years (SD=19.7). Oral surgeons represented 62% of the submitting doctors. Of 200 cases submitted with clinical impression of melanocarcinoma only four cases received a microscopic diagnosis of melanocarcinoma, and the remaining cases received various diagnoses as displayed in Table 1. Nine of thirteen cases receiving microscopic diagnosis of melanocarcinoma were submitted with various incorrect clinical impressions as displayed in Table 2. Regarding correctness of clinical impression, there was no significant difference between oral surgeons and other submitters, (p=0.3642.)
Conclusions: While the number of suspected melanocarcinomas (200) is small, the histological diagnosis of 13 in this database is rather large. Results of the study demonstrate the difficulty in clinical diagnosis of melanocarcinoma and substantiate that no discriminating difference exists in clinical acumen of submitters. Study presents other common oral lesions mistaken for melanocarcinoma.