The present status regarding the etiology of tumor of the parotid gland, which for many years was the subject of a lively academic discussion, has been summarized by Ewing1 as follows:
1. The endothelial origin has been disproved.
2. No single source of mixed tumor meets all requirements. Some are distinctly adenomatous and probably arise from the acini and the ducts of the gland in which they are well incorporated. Others are encapsulated or extraglandular, and take the form of basal cell or adenocystic epithelioma. These probably arise from misplaced and occasionally embryonal portions of gland tissue. Branchial remnants may possibly be connected with this group.
3. The derivation of mucous tissue and cartilage from gland epithelium has been satisfactorily proved, and there is no necessity of including in the originating tissue any cartilaginous structures.
McFarland,2 reporting a series of ninety cases of tumor of the parotid gland
MARTIN TM. TREATMENT OF TUMOR OF THE PAROTID GLANDSURVEY OF THE RESULTS OBTAINED AT THE BARNARD FREE SKIN AND CANCER HOSPITAL. Arch Surg. 1938;36(1):136-143. doi:10.1001/archsurg.1938.01190190139009