Aggressive thyroid cancer in low-risk age population.

Seventy-eight patients under the age of 40 (low-risk patients) who had undergone surgical treatment for well-differentiated thyroid carcinoma were referred from 1979 to 1986 to our hospital for adjuvant therapy. A subgroup of 37 patients, 14 with apparent aggressive cancer, was studied. This study group consisted of 27 female and 10 male patients with mixed papillary and follicular cancer, who ranged in age from 11 to 40 years. Nodal disease occurred in 27 (73%) patients and invasiveness in 30 (81%) patients and involved multiple areas in 9 (24%) patients. Recurrence occurred in 14 (38%) patients and visceral metastases occurred in eight (22%) patients. All patients underwent appropriate surgery, but microscopic residual disease was seen in 15 patients and gross residual disease in seven patients, so that 31 patients underwent iodine-131 therapy, and 17 of these patients also underwent external radiation therapy. Three patients died of their disease, whereas 24 (65%) patients are free of disease and 9 (24%) patients are alive with disease. An additional 7 (19%) patients were initially seen in the fifth to seventh decade after decades of neglected thyroid disease, which culminated in residual cancer and death. Although low-risk categorization for thyroid cancer appears valid, its rigid application in support of conservative treatment may lead to inadequate primary treatment and underdiagnosis of cancer in thyroid nodule disease in the low-risk age population.