Minor salivary gland tumours: Malignant or benign? A 10-year local retrospective review

Abstract

Background: This study reports on our local incidence of minor salivary gland tumours (MSGT).

Methods: This was a retrospective descriptive study including all patients with MSGT treated at Tygerberg Hospital from 2015 to 2024.

Results: Benign and malignant tumours’ incidence was almost equal at 46.46% and 53.54%, respectively (N = 99). Pleomorphic adenomas were the most common tumour overall (38.38%) and the most common benign tumour. Polymorphous low-grade adenocarcinoma (PLGA) was the most common malignant tumour (15.15%). The palate was the most common site. Primary sites other than lips and palate had a 93.23% malignant incidence. Benign tumours occurred statistically significantly in younger patients than malignant tumours (p < 0.001) (42.74 years versus 56.02 years).

Conclusion: We did not see the high malignant incidence that is frequently reported in otorhinolaryngology textbooks. Pleomorphic adenomas remain the most common and occur most commonly in the palate. We did show an unusually high incidence of PLGA. Primary sites other than palate and lips should raise the suspicion of malignant MSGT.

Contribution: The study highlights the importance of reporting on local data because disease patterns may vary greatly based on genetic and geographical differences. Further investigation is needed to explain possible local factors contributing to the high incidence of PLGA.