Salivary gland tumors: review of 643 cases.

643 cases of salivary gland tumors constitute two series of histological sections that were studied from hospitals and dental schools in Southeast Scotland and Southern Ontario. The Scottish series represented epithelial tumors of the parotid and intra-oral salivary glands, but the Canadian series also included tumors of the submandibular and sublingual glands. Classification was based on that recommended by the World Health Organisation (Thackray 1972). While direct statiscal comparisons between the two series are not appropriate, the differences between them suggest that malignant tumors are more common in Canada. The Scottish series contains the largest proportion of benign salivary tumors so far reported. In the Scottish series, 88.7% of parotid tumors were benign compared with 51.9% of Canadian series. In the Canadian series from the submandibular glands, 21.2% only were benign. Of the intra-oral salivary tumors, 62.2% from the Scottish series were benign compared with only 34.7% from the Canadian series.