A retrospective investigation of minor risk factors as prognostic predictors and treatment indications in oral squamous cell carcinoma oleh Shin-ichi Yamada, Eiji Kondo, Masao Hashidume, Akinari Sakurai, Hiroki Otagiri, Naoki Matsumura, Kiriko Kubo, Yusuke Hakoyama, Junichi Yajima, Masafumi Morioka, Yukiko Akahane, Kazunori Anzai, Koichi Goto, Takeshi Uehara, Hironori Sakai, Hiroshi Kurita