Clinico-pathological audit of oral mucosal lesions among patients at the Muhimbili National Hospital in Tanzania

Background: Oral mucosal lesions (OMLs) are common in adult population although not as frequently reported as for traditional oral health problems. These lesions include; ulcerative/vesiculobullous, white/red, pigmented lesions, benign mucosal swellings and tongue mucosal lesions. Some OMLs are either malignant, premalignant or benign while others are caused by common infectious agents. Some of them may result from autoimmune reaction while others may be associated with systemic diseases including HIV/AIDS. Lesions suspected to have pre-malignant properties need close follow-up, early recognition and management. Due to the variation in clinical presentation and the uncertainty as to whether a lesion is malignant or benign, OMLs pose a challenge with regard to diagnosis and management. The burden of OMLs in Tanzanian populations has hardly been documented. Objective: The objective of this study was to determine the Occurrence and clinico- pathological presentation of oral mucosal lesions in patients presenting for treatment in the Oral Surgery department of the MNH. Study Design: This was a prospective cross sectional descriptive study. Study Setting: The study was done at the MNH at the oral surgery out patient clinic and in wards where oral surgical patients were admitted. Study Duration: The study was conducted over an 8-month duration. Methods: The subjects who consented to participate in the study were interviewed using a pre-tested questionnaire. Oral examination was done and the details of findings, and investigations results including biopsy were recorded. The data were analyzed using the SPSS programme version 12.0.1 and interpretation of the results done. Results: The prevalence of OMLs was 4.6%. The age of subjects ranged from 1 to 86 years with mean 41.5 +/- 19.9 years and the male to female ratio was 0.72:1. Majority (56.3%) had primary education only while 17.5% had no formal education. 76 (47.5%) subjects indicated they drank alcohol, 23(14.4%) smoked tobacco and 15 (9.4%) used snuff. 34 types of OMLs were observed from the 172 lesions and these were categorized into; white/red OMLs 24 (14.0%), ulcerative lesions 64 (37.2%), pigmented OMLs 37 (21.5%), mucosal swellings 34 (19.8%) and tongue mucosal lesions 13 (7.6%). Out of the oral ulcerative OMLs 34 (53.1 %) were malignant and for pigmented OMLs and oral mucosal swellings the proportion of malignant OMLs was 56.8% and 23.5% respectively. Squamous cell carcinoma (See) was the most frequent OMLs observed in 34 (21.3%) of the subjects followed by Kaposi's sarcoma (KS) in 19 (11.9%) subjects. More females were found to have had see and "(S than males and the most affected age was 60 years and above for see and 20-49 years for KS. All patients with KS were HIV positive and 94.1 % with see presented with clinical stage IV lesions. Other OMLs with a relatively higher frequency included; peripheral granuloma (7.5%), traumatic ulcer (5.8%), haemangioma (5.2%), adenocarcinoma (4.7%), pseudomembraneous candidiasis (4.6%), aphthous ulcer (4.1%), geographic tongue (3.5%) and fissured tongue (2.3%). The most common site for occurrence of OMLs was the lower lip followed by the hard palate and anterior 2/3 of the tongue. Conclusion: Results indicate that OMLs is a problem in Tanzania. The malignant lesions constituted the large proportion of OMLs observed. The most common lesion type was see followed by KS. The most common site for the OMLs was the lower lip followed by the hard palate