The American College of Surgeons Commission on Cancer (CoC) has conducted national Patient Care Evaluation (PCE) studies since 1976. Over 1500 hospitals with CoC-approved cancer programs were invited to participate in this prospective cohort study of U.S. thyroid carcinoma cases treated in 1996. Follow-up will be conducted through the National Cancer Data Base. Of the 5584 cases of thyroid carcinoma, 81% were papillary, 10% follicular, 3.6% Hürthle cell, 0.5% familial medullary, 2.7% sporadic medullary, and 1.7% undifferentiated/anaplastic. Demographics and suspected risk factors were analyzed. Fine-needle aspiration of the thyroid gland (53%) or a neck lymph node (7%), thyroid nuclear scan (39%), and ultrasound (38%) constituted the most frequently utilized diagnostic modalities. The vast majority of patients with differentiated thyroid carcinoma presented with American Joint Committee on Cancer Stage I and II disease and relatively small tumors. For all histologies, near-total or total thyroidectomy constituted the dominant surgical treatment. No lymph nodes were examined in a substantial proportion of cases. Residual tumor after the surgical event could be documented in 11% of cases, hypocalcemia in 10% of cases, and recurrent laryngeal nerve injury in 1.3% of cases. Complications were most frequently associated with total thyroidectomy combined with lymph node dissection. Thirty-day mortality was 0.3%; when undifferentiated/anaplastic cancer cases were eliminated, it decreased to 0.2%. Adjuvant treatment, probably underreported in this study, consisted of hormonal suppression (50% overall) and radioiodine (50% overall). In addition to offering information concerning risk factors and symptoms, the current PCE study compliments the survival information from previous NCDB reports and offers a surveillance snapshot of current management of thyroid carcinoma in the U.S. Identified opportunities for improvement of care include 1) more frequent use of fine-needle aspiration cytology in making a diagnosis; 2) more frequent use of laryngoscopy in evaluating patients preoperatively, especially those with voice change; and 3) improved lymph node resection and analysis to improve staging and, in some situations, outcomes.