[Clinical review of mucoepidermoid carcinomas]

Mucoepidermoid carcinoma is a rare head and neck cancer tumor, composed of both mucous and epidermoid cells. We retrospectively reviewed the case of 36 such patients hospitalized in the last 24 years (between 1978 and 2002) at Kurume University Hospital, focusing on origin, treatment, and treatment outcome. In this study, 33 patients undergoing currative treatment were studied in detail. Tumors originated in major salivary glands in 24 and in the oral cavity, paranasal cavity, and oropharynx in 3 each. Salivary gland carcinomas were graded, clinically and histopathologically based on the criteria of Goode et al. as follows: low (n = 3), intermediate (n = 3), and high (n = 18). All patients underwent radical surgery. Lymphnode metastasis was detected in 9, distant metastasis in 6 (lung: 4; liver: 1; bone: 1), and local recurrence in 5 patients. Lymphnode recurrence was detected in 3. Survival was calculated with Kaplan-Meier's methods. Five-year overall survival was 64%, i.e., 56% in salivary gland malignancy, 67% in oral cavity malignancy, 100% in paranasal cavity malignancy and 100% in oropharynx malignancy. Five-year survival was 76% in T2, 75% in T3, 51% in T4. Five-year survival in NO was 80% and 22% in N+ cases, with a statictically significant difference (p < 0.05). Five-year survival was 71% in stage I, 83% in stage II, and 54% in stage IV. Five-year survival in low and intermediate grade was 100%, whereas that in high grade was 43%. The 21 patients undergoing modified neck dissection has a 5-year survival of 52%. In 20 patients undergoing postoperative radiotherapy, 4 died of local recurrence. In 31 patients not undergoing chemotherapy, 6 died of distant metastasis. These results emphasize the necessity of radiotherapy and chemotherapy after surgical treatment for head and neck mucoepidermoid carcinoma.