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Morphological pattern of salivary gland tumours.

OBJECTIVE
To delineate the spectrum of salivary gland tumors in our setup.


SETTING
The Aga Khan University Medical Centre, Karachi.


METHOD
Tumors were analysed considering histological type, age and sex of the patients and anatomic location. The diagnosis of individual tumours was based on the 1991 World Health Organisation Classification.


RESULTS
During the span of eight years (1991-1998), 379 cases of salivary gland tumours were diagnosed. Of these, 205 (65.7%) were male and 174 (34.3%) were female. The median age at the time of diagnosis was 35 years. The median age for patients with malignant lesions (44 years) was 12 years older than those with benign tumours (34 years). Overall, malignant tumours were seen more frequently in males, however benign tumours were distributed equally between the two sexes. The most common site was parotid gland (82.85%). Only five cases of minor salivary gland tumours were seen. The most frequently diagnosed benign salivary gland neoplasm was pleomorphic adenoma (84.5%), followed by Warthin's tumours (6.18%), Mucoepidermoid carcinoma was the most commonly encountered malignant lesion (56.9%), followed by adenoid cystic carcinoma (19.6%).


CONCLUSION
Plemorphic adenoma was the most common benign salivary gland tumour and mucoepidermoid carcinoma was the most frequent malignant neoplasm. Parotid gland was the most common site of origin in both benign and malignant tumours. The overall relative frequency of salivary gland tumours in this series correlates with that reported in the international literature.