Surgical treatment of postoperative, incidentally diagnosed small sporadicC-cell carcinomas of the thyroid

Background and aims: The surgical strategy in small sporadic C-cell carcino mas of the thyroid that are incidentally diagnosed after,goiter resection f or benign disease is controversial. It remains unclear whether a completion thyroidectomy should be performed in every case. Patients mid methods: We present nine patients who were operated on between October 1992 and October 1997 in whom an unexpected, small sporadic C-cell carcinoma (seven with pT 1, two with pT2,) was found in the postoperative histology. Results: All pa tients were calcitonin negative and there were no signs of the disease bein g inherited (no familial history, negative RET protooncogene). No patient u nderwent a completion thyroidectomy. All patients had a follow-up with pent agastrin-stimulated calcitonin and carcinoembryonic antigen (CEA) 3 months, 6 months and annually after the operation. No patient became calcitonin po sitive or showed any other signs of tumor recurrence after a follow-up peri od of 2-7 years. Conclusion: A completion thyroidectomy is not necessary in small sporadic C-cell carcinoma that is incidentalIy diagnosed after resec tion for benign disease if there is no sign of familial cancer and if calci tonin is negative. A close follow-up is necessary.