RIMARY malignant melanoma of the oral P cavity is an extremely rare tumor, but it may not be as uncommon as the number of reported cases would indicate. AfBeck8 reported an incidence of 0.4% among 317 cases of malignant melanoma; Baxter,l* 0.6% among 170 cases; Hobaek,'O 1.2% among 269 cases; and Adair.2 1.3% among 400 cases. The first case of primary malignant melanoma of the oral cavity was reported by Webefl in 1859. New,62 in 1921, and Patterson>' in 1926, surveyed the literature and could collect only 24 cases to which each of them added a new case. Fuhs and Kumer,82 in 1929, and Lence,'* in 1937, could gather only 31 and 39 cases respectively. Baxter," in 194 1, discussed at length the clinical findings, histopathology, and treatment of 55 cases of this neoplasm published in the literature.
Only 91 cases of primary oral malignant melanoma have been reported in the past 100 years (1859-1957) and if to these are added 6 cases of Adair,? 4 cases of Elmes and Baldwin,*' 1 case of Affleck: and 1 case of Gleave,a all of which lack description, this would bring the total to 103 cases. Some of the present authors have already reported 1 case from the files of the School of Dentistry,*2 and another case from the records of the University Hospital is included in this paper, bringing the total to 105 cases. Two cases of Soderberg and Padgett,71 1 case of Grohe,a7 and 1 case of Krompecher'a are not counted in this series since they lack convincing evidence concerning their authenticity as malignant melanoma. Their age, clinical behavior, and prognosis and even histopathology does not fit in with the description of this neoplasm.
The neoplasm occurred in men in 53 cases and in women in 28. Thus, the primary malig-From the divisions of Oral Pathology and Operative Dentistry.