Clinical evaluation of the oral multiple primary cancer

• Published in: Journal of Japan Society for Oral Tumors Vol. 4; no. 2; pp. 257 - 263
• Main Authors: Shionoya, Kenichi, Okabe, Sadao, Matsuki, Kiyohiro, Endoh, Takeshi, Matsuki, Shigeo, Izumo, Toshiyuki, Kirita, Tadaaki, Amagasa, Teruo
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Oral Oncology 1992
• Subjects: Metachronous; New criteria; Oral multiple primary cancer; Synchronous
• DOI: 10.5843/jsot.4.257
• ISSN: 0915-5988

This paper presents a clinical evaluation of the oral multiple primary cancer at the Department of Oral Surgery, Saitama Cancer Center. From 1975 to 1991, 15 patients of oral multiple primary cancer were treated. New criteria of oral multiple cancer are suggested as follows: (1) the tumors are found in different sites which are classified by UICC, (2) in the case of the same site, the tumors exist in both the right and the left side, (3) in the case of the same side, the tumors are completely separated at least at a distance of 1.5 cm and non-neoplastic tissue is recognized between them, (4) pathologically, the tumors show the malignancy, (5) the tumor occurs over 10 years after the disappearance of the malignant tumor by radiotherapy (radiation induced cancer) . The incidence of oral multiple primary cancer was 3.0% among 496 oral carcinomas at the Department of Oral Surgery, Saitama Cancer Center. Six out of 15 cases were male and 9 were female. The age ranged from 25 to 80 years old and their average was 58.2 years old. The tumors were seen synchronously in 4 cases and metachronously in 11 cases. The additional tumors occurred on average 3 years and 8 months after the recognition of the first tumor. The secondary lesion was generally discovered at the earlier stage as compared to that of the primary one. The relation between drinking, smoking and carcinogenesis was not recognized. These evaluations suggest that long-term follow-up and careful examination are necessary for getting successful outcome.