During the period from April 1974 to March 1993, 357 patients received surgical treatment for papillary and follicular carcinoma of the thyroid gland at the Department of Head and Neck Surgery of National Kyushu Cancer Centre, Japan. In this paper, we review the various clinico-pathological features of these patients and analyse their influence on patient survival. While the majority of the patients' ages ranged from the third through seventh decade, only the patients older than 40 years old died. In papillary carcinomas, there was a statistically significant difference in the survival rate between younger (less than 45 years old) and older (45 years of age or older) patients. The rate of patients who died of thyroid cancer also increased in the cases with extra-thyroidal tumour invasion, and metastasis to distant organs. A multivariate analysis also showed that the age, extrathyroidal invasion and distant metastasis are significant prognostic factors. However, sex, histology and lymph node metastasis were not prognostic factors for survival.