No structural recurrence in patients with postoperative indetectable calcitonin after surgery for medullary thyroid cancer
Carolina Nylén, Christofer Juhlin, Jan ZedeniusAbstract
Introduction
The recommended postoperative follow-up for medullary thyroid cancer (MTC) is 10 years, with yearly calcitonin and CEA. An undetectable calcitonin after surgery for MTC is an independent favorable prognostic factor with previous studies showing up to 94% relapse-free survival. The purpose with this study was to investigate the incidence of structural recurrence after MTC surgery for patients with undetectable postoperative calcitonin in a single center MTC cohort.
Methods
A retrospective study was conducted including all patients with MTC operated 2000- 2021 at the Karolinska University hospital. Postoperative and follow-up calcitonin levels were noted as well as biochemical and/or structural recurrence. Undetectable calcitonin was defined as <0.6 pmol/l.
Results
63 patients (38 women, 25 men) were operated during the study period. 12 (19%) patients had RET germline mutations, the remaining were sporadic MTC. 16 patients had undetectable calcitonin at the first postoperative follow-up. Only two (2/16) of these patients had rising calcitonin at 7 and 11 years respectively, without any detected structural recurrences. Median follow-up time was 11 years.
Discussion
None of the patients operated for MTC with a postoperative undetectable calcitonin showed structural recurrence during the follow-up time. This finding is in line with other studies. Based on the excellent prognosis, we suggest that the current follow-up for MTC-patients with postoperative undetectable calcitonin should be discussed and modified.