Treatment of squamous cell carcinoma of the retromolar trigone

OBJECTIVES: Retromolar trigone (RMT) squamous cell carcinoma is uncommon but notorious for poor prognosis. We reviewed our experience in the management of RMT cancer to determine survival rates and to identify prognostic factors. METHODS: Fifty patients with RMT squamous cell carcinoma were treated with surgery and/or radiation or chemoradiation therapy between July 1993 and June 2004 at Chang Gung Memorial Hospital, Taiwan. Patients were followed up for 3 to 106 months (mean, 36 months). There were 6 stage I, 13 stage II, 4 stage II, and 27 stage N patients. RESULTS: The 5-year actuarial survival rate for stage I to N and all stages were 100%, 74.1%, 75%, 43.6%, and 60.6%, respectively. Seventeen (34%) patients had maxilla bone (11 [22%]) or mandible bone (9 [18%]) invasion. Eleven (22%) patients had masticator space involvement. Cervical metastasis rate was 26%. Multivariate analysis revealed that masticator space involvement, neck recurrence, and cervical metastasis were poor prognosticators of survival by order. The maxilla bone was more apt to be involved by RMT cancer than the mandible. Patients with masticator space involvement had a 5-year actuarial survival rate of 22.5% and the mean survival time was only 37.8 months. CONCLUSIONS: RMT squamous cell carcinomas are aggressive tumors. The maxilla is more apt to be involved than the mandible. Deep infiltration of the masticator space and invasion of the maxilla and mandible worsen the prognosis.