Predictors of recurrence and disease-free survival for salivary gland tumors among children and young adults in Kampala, Uganda: a retrospective follow-up study

Abstract

Background Salivary gland tumors are a group of tumors which are highly heterogeneous, and they are uncommon among children and young adults. We aimed to investigate the predictors of recurrence and disease-free survival for salivary gland tumors among children and young adults. Methods We retrospectively extracted clinical, pathologic, and follow-up data of patients who were diagnosed histologically with salivary gland tumors from January 2013 to December 2018 at the department of pathology, Makerere University in Kampala, Uganda. Then, we applied Cox regression analysis to determine the predictors of disease-free survival using hazard ratio as the measure of probability of the survival with 95% confidence interval. We also used Kaplan–Meier curves to analyze the disease-free survival. P ˂ 0.05 was considered significant. Results A total of 144 patients with salivary gland tumors were included in the present study who were aged not more than 20 years with mean age of 13.9 ± 4.5 years. Over one quarter (26.4%, n = 38) of the salivary gland tumors that were analyzed in the present study were malignant. The prevalence of recurrence was (27.1%, n = 39), and the mean disease-free survival was 58.7 ± 1.9 months. Category of the salivary gland (AHR = 1.36, 95% CI = 0.137–0.942, p = 0.037) and behavior of the tumors (AHR = 1.82, 95% CI = 0.729–0.990, p = 0.023) were the potential predictors of disease-free survival. Conclusion Over one quarter of the patients had malignant salivary tumors, and also, one-third of the patients developed recurrence at the end of the follow-up period of 6 years. Involvement of minor salivary glands and having a malignant salivary gland tumor both have shown increased risk of recurrence as well as short disease-free survival. Therefore, patients with minor salivary gland involvement and those with malignant variants require optimal surgical resection of the tumors for possible prevention of early recurrence and increasing the survival of the patients without relapse of such tumors after initial resection of the primary lesions.