The following is a summary of “Natural History and Predictive Factors of Outcome in Medullary Thyroid Microcarcinoma,” published in the October 2023 issue of Endocrinology by Kesby, et al.
The management of sporadic medullary thyroid microcarcinoma (MTC) smaller than 1 cm remained a topic of debate due to conflicting prognosis reports. Given their often incidental diagnosis, deciding on further treatment and follow-up poses a challenge in clinical practice. For a study, researchers sought to present the outcomes of surgically managed sporadic micro-MTC within a specialized endocrine surgery and endocrinology unit. Additionally, the research seeks to identify associations between recurrence and disease-specific survival in this particular patient population.
Micro-MTC cases were identified from a prospectively maintained surgery database, with pathology slides reviewed for tumor grade determination. Key endpoints included recurrence, time to recurrence, and disease-specific survival. Prognostic factors examined comprised tumor size, grade, lymph node metastasis (LNM), and postoperative calcitonin levels.
Over the period from 1995 to 2022, 64 patients were diagnosed with micro-MTC, excluding 22 due to hereditary disease. The included patients, with a median age of 60 years and a tumor size of 4 mm, demonstrated incidental diagnosis in 86% of cases. The diagnosis was made by chance in 36 (86%) of the cases, with 4 (10%) being high grade, 5 (12%) having LNM, and 9 (21%) having elevated postoperative calcitonin. During a median follow-up of 6.6 years, 12% experienced recurrence, and 7% succumbed to MTC. High grade and LNM were associated with 10-year survival estimates of 75% compared to 100% for low grade and no LNM (hazard ratio = 831; P < .01). Factors such as high grade, LNM, and increased calcitonin were linked to recurrence (P < .01). Tumor size and the type of surgery showed no statistically significant associations with recurrence or survival. Notably, no patients with low-grade micro-MTC and normal postoperative calcitonin developed recurrence.
Sporadic micro-MTCs, commonly incidentally detected, generally exhibited favorable outcomes. Tumor size is not significantly linked to prognosis. Utilizing grade, LNM, and postoperative calcitonin aids in identifying patients at risk of recurrence, facilitating personalized management approaches.
Source: academic.oup.com/jcem/article/108/10/2626/7086077
