Rates of tumour recurrences and metastases after surgical removal of malignant salivary gland tumours throughout 5-years of follow-up: A retrospective single-centre study

Abstract

Purpose: The purpose of the current study was to evaluate the frequency rates of tumour recurrences and rates of metastases in patients with surgical removal of malignant salivary gland tumours throughout 5 years of follow-up after initial therapy, and determine which salivary gland and histological diagnosis are the major contributors for the occurrence. Methods: Between 2005 and 2017, 74 patients underwent surgical removal of localized malignant cancers of the salivary glands. Data were analysed retrospectively from our tertiary hospital database. The demographic characteristics (age and gender) were obtained from the patients' records. Pearson's χ-square test and logistic regression were used to analyse the data with p < 0.05 as statistically significant. Results: Malignant salivary gland tumours were mostly diagnosed at parotid gland in 51.4% of cases, thus majority of patients underwent surgical extirpation (37.8% of cases) of tumour removal. Adenocarcinoma was the most common form of malignancy (19 patients, 25.6%), followed by adenoid cystic carcinoma (13 patients 17.6%) and mucoepidermoid carcinoma (11 patients, 14.9%). Postoperative complications; namely tumour recurrences were detected in 8 patients (10.8%) throughout 5 years of follow-up after initial therapy. Metastases were observed in 6 patients (8.1%), and facial nerve paralyses were diagnosed in 19 (25.7%) of all patients and with no specific risk factors, that could have contributed to the occurrence of nerve damage. Conclusions: A significant proportion of patients who are presumed to be cured of their disease through 5 years after initial treatment for salivary gland cancer will be found to develop late disease recurrences or metastases. Keywords: Malignant tumours, Salivary glands, Tumour recurrence, Metastases, Retrospective analysis