Of 731 patients with papillary thyroid cancer, 91 had metastases outside regional lymph nodes. The most common site was intrathoracic, occurring in 73 of the 91 patients. Miliary, micronodular pulmonary metastases, with iodine 131 (1-131) uptake and "curable'* by 1-131 treatment were encountered in seven patients. It has not been established whether this was a transient stage in additional patients. In 38 patients rounded, macronodular pulmonary metastases were found. Another 21 patients had unilateral pulmonary infiltration and mediastinal enlargement. Pulmonary infiltrations may be hematogenic, or may possibly occur via regional, mediastinal lymph nodes. Mortality within 1 year of the diagnosis of distant metastases exceeded 50%. Occurrence of distant metastases showed a slight but highly significant association with male sex, advanced age, and advanced local tumor stage. Better prognostic determinants are, however, required if adequate treatment of the individual patient with papillary thyroid cancer is to be achieved.
Cancer 61:1-6, 1988.
APILLARY THYROID CANCER runs an indolent clin-P ical course. A very common finding is metastases to regional lymph nodes, which also include lymph nodes in the upper mediastinum. These lymph node metastases are not indicative of distant metastases, as in most other malignant diseases. ' Metastases remote from the neck region are a rather uncommon event. The rate of distant metastases varies in different reports.* Also the implications of such events seem to differ.3 This report concerns 9 1 patients with distant metastases from papillary thyroid cancer treated between 1956 and 1978. The 9 1 patients were sampled from a defined population and have been followed up until 1986.
Patients and Methods
From 1956 through 1978, 2345 patients with the diagnosis of thyroid cancer were registered in the Cancer Registry of Norway. Nearly 50%, more than 1150 of these patients, were eventually treated in The Norwegian Radium Hospital and their patient records were From the Departments of *Surgical Oncology, tPathology, SDiagnostic Radiology, and $Nuclear Medicine, Norwegian Radium Hospital, Montebello, Oslo, Norway.