Recurrences of Thyroid Cancer After Radical Surgery and Complementary Treatment: Are Macroscopic, Microscopic, Scintigraphic, and Biochemical Criteria Sufficient in the Evaluation of Radicality of Primary Treatment?

Abstract

From 1974 to 1999, 1,001 patients were operated on for thyroid cancer, including 778 (78%) for differentiated thyroid cancer and 223 (22%) for other thyroid malignant neoplasms. Radical operations were performed in 716 (92%) patients with differentiated thyroid cancer and in 85 (38%) patients with other thyroid malignant neoplasms. After surgery, all patients underwent various methods of complementary treatment, depending on cancer type and grading (levothyroxine, 131I, radiotherapy and/or chemotherapy). These patients had no evidence of persistent disease after finishing treatment (Tg, CEA, calcitonin, scintigraphy). We observed recurrences of thyroid cancer, although macroscopic, microscopic, biochemical, and scintigraphic criteria of radicality were present. At 18 months’ to 24 years’ follow-up, we observed recurrences in 94 (11.7%) of 801 patients treated radically, including in 53 (7.4%) of 716 patients with differentiated thyroid cancer and in 41 (48%) of 85 patients with other thyroid malignancies. Among 37 patients with thyroid bed recurrence, 18 (48.6%) underwent radical operations and 19 (51.4%) palliative ones. Of 33 patients with regional lymph node recurrence, radical operations were performed in 26 (78.8%) and palliative ones in seven (21.2%). Of 24 patients with distant metastases, four (17%) (with single metastasis) underwent surgery (three radical operations and one palliative one). Other methods of treatment were used in the remaining patients. Occurrence of thyroid cancer recurrences in the thyroid bed and lymph nodes indicates that macroscopic, microscopic, and scintigraphic criteria of radicality are not sufficient. Recurrences after radical surgery are more infrequent in patients with differentiated thyroid cancers than in those with other thyroid malignant neoplasms. In many patients, thyroid bed and lymph node recurrences can be removed radically during surgery.