A clinical study of 104 patients with tongue cancer and the relationship between DNA ploidy and prognosis in 41 cases

Abstract

One-hundred and four patients with previously untreated tongue cancer seen in our department between 1986 and 1998 were enrolled in a clinical study. The DNA ploidy patterns observed in fresh frozen specimens obtained from 41 patients were analyzed, and prognostic factors were investigated. According to the TNM classification (UICC 1997), 43 patients had stage I tumors, 29 had stage II tumors, 17 had stage III tumors, and 15 had stage IV tumors. The 5-year cause-specific survival rates for each stage were 94.7%, 64.4%, 50.0% and 45.7%, respectively. The most frequent cause of death associated with the original disease was the recurrence of the disease in cervical lymph nodes (19/27, 70.4%). The occurrence of late cervical metastasis was high among patients with a T2N0 disease. Patients with stage II disease should undergo elective neck dissection or be carefully monitored using ultrasonography. Among the 41 cases in which the DNA ploidy pattern was analyzed, diploid patterns were found in 30 cases and aneuploid patterns were found in 11. The 5-year cause-specific survival rate and the 5-year locoregional control rate were significantly lower for the aneuploid cases (18.2%, 38.9%) than for the diploid cases (66.5%, 69.8%) (p = 0.0003, p = 0.0339). The incidence of distant metastasis was significantly higher among the aneuploid cases (6/11, 54.5%) than among the diploid cases (3/30, 10.0%) (p = 0.0058). The ploidy pattern, as determined by flow cytometric DNA analysis, may reflect the malignancy grade of tongue cancers.