Trends in Diagnostics, Surgical Treatment, and Prognostic Factors for Outcomes in Medullary Thyroid Carcinoma in Norway: A Nationwide Population-Based Study.

Abstract

BACKGROUND:

Medullary thyroid carcinoma (MTC) is rare. Nationwide population-based studies are important to evaluate its clinical course.

OBJECTIVES:

To describe all patients with MTC in Norway during 1994-2016 and compare time-related trends in diagnostics and surgical treatment, including prognostic factors for biochemical cure and disease-specific survival (DSS).

METHODS:

This retrospective population-based cohort study includes data for 228 out of 237 patients (96%) with MTC; 201 patients were surgically treated. Patients were identified in the 4 regional centers treating MTC and by the Cancer Registry of Norway. Data were collected from patients' files. Trends were compared over 2 study periods.

RESULTS:

MTC accounted for 4.2% of thyroid carcinomas. During the study periods, the incidence increased from 0.18 to 0.25: 100,000 per year, preoperative diagnostics improved with increased use of calcitonin, ultrasound, and fine-needle cytology (p = 0.010, p < 0,001, and p = 0.001), patients were diagnosed at an earlier tumor stage (p = 0.004), and more patients were cured (p = 0.002). Via multivariate analysis of patients with metastatic lymph nodes, independent prognostic factors for cure were: a low ratio of metastatic and total number of dissected lymph nodes (p = 0.021) and no extrathyroidal extension (p = 0.030). Independent prognostic factors for DSS were: no distant metastasis, a younger age, and a low ratio of metastatic and dissected lymph nodes (p = 0.005, p = 0.020, p = 0.022).

CONCLUSIONS:

Preoperative diagnostics have improved over time with increased therapeutic control. A low ratio of metastatic and dissected lymph nodes predicts better outcomes in patients with metastatic lymph nodes.

• Authors: Else Marie Opsahl, Lars Andreas Akslen, Ellen Schlichting, Turid Aas, Katrin Brauckhoff, Anne Irene Hagen, Alf Frimann Rosenlund, Eva Sigstad, Krystyna K Grøholt, Lovise Mæhle, Lars Fredrik Engebretsen, Lars H Jørgensen, Jan Erik Varhaug, Trine Bjøro
• Journal: European thyroid journal (Eur Thyroid J) Vol. 8 Issue 1 Pg. 31-40 (Jan 2019) ISSN: 2235-0640 [Print] England
• PMID: 30800639 (Publication Type: Journal Article)