Treatment of squamous carcinoma of the retromolar trigone.

Since squamous carcinoma of the retromolar trigone is unusual, there is a paucity of information in the world's literature to use as a reference for selecting treatment and determining pertinent factors affecting prognosis. Consequently, an analysis of the medical records of 110 patients with biopsy proven squamous carcinoma originating in the retromolar trigone, seen and treated entirely at The University of Texas M.D. Anderson Hospital and Tumor Institute at Houston from 1965-1977, with at least 5 years of follow-up, was completed and constitutes the substance of this study. Local-regional control and survival were correlated with age, sex, presenting signs and symptoms, dental status, T and N classification, histologic grading, surgical findings, and the various modalities of treatment. Seventy lesions were staged T1-T2 and 77 patients had N0 necks. Thirty-five patients received a planned combination of surgery and x-ray therapy to the primary and/or neck. A composite resection was performed in 48 patients with the closure accomplished primarily or with a skin graft. The various surgical approaches are critiqued with a favorable emphasis on the marginal resection of the mandible and a modification of the radical neck dissection. The ultimate failure in the primary and the neck was 7% (8/110) and 10% (11/110) respectively. Single modality treatment whether it is surgery or irradiation appears equally adequate regardless of the T or N Stage. However, more T3-T4 cancers were treated initially with surgery. Thirty-six patients developed a second primary cancer of which 29 were in the upper aerodigestive tract. The low 5-year survival of 20% (29/110) reflects a poor salvage of the second primary and a high incidence of intercurrent disease in this elderly group of patients.