12486 Clinical Manifestations And Mortality Outcomes Of Multiple Endocrine Neoplasia Type 2 Patients With Medullary Thyroid Cancer In Korea Using The National Health Insurance Service Database
Authors: Hwang Y a , Kim K , Yu M , Hong N , Rhee Y 
Published: October 2024

Abstract
Disclosure: Y. Hwang: None. K. Kim: None. M. Yu: None. N. Hong: None. Y. Rhee: None.
Objective: Multiple Endocrine Neoplasia Type 2 (MEN2) is a rare, inherited disorder that most commonly presents as medullary thyroid carcinoma (MTC). This genetic condition is associated with mutations in the RET proto-oncogene, activating RET tyrosine kinase. With MTC being the most life-threatening aspect, the mortality rates for MEN2 patients can vary depending on the type and timing of intervention. However, data on the mortality and morbidities of MEN2 in South Korea is limited. This study aims to utilize data from the National Health Insurance Service (NHIS) to examine the prevalence of comorbidities and mortality of MEN2 patients with MTC in South Korea. Methods: This study analyzed likely MEN2 patients using data from the Korean NHIS database spanning 2003 to 2020. The operational definition of MEN2 included individuals either 1) diagnosed with MTC and having an ICD-10 code for MEN (D44.8), or 2) diagnosed with MTC and presenting with at least one associated condition, such as primary hyperparathyroidism, pheochromocytoma and paraganglioma (PPGL), Hirschsprung's disease, cutaneous amyloidosis, or neuroma. Hirschsprung's disease, cutaneous amyloidosis, or neuroma were defined using ICD-10 code. Cases were matched in a 1:10 ratio by age, sex, and index year with controls who did not have any MEN2-associated diseases. Results: Our study evaluated 116 patients with likely MEN2 accompanied by MTC (mean age 43.0 ± 17.0 years; 33.6% male) and compared them to an age- and sex-matched control group of 1,160 individuals. The average age at diagnosis of MTC among the MEN2 patients was 43.6 years. A total of 86.2% of these patients (n=100) underwent total thyroidectomy, and 14.7% also received radioactive iodine ablation. Among 116 patients, 21 (18.1%) were diagnosed with primary hyperparathyroidism and underwent parathyroidectomy. Additionally, 25 out of 116 patients (21.6%) was diagnosed as PPGL. The analysis revealed a higher prevalence of comorbidities among the MEN2 patients, including diabetes mellitus (9.5% vs 5.1%, p=0.047), hypertension (46.6% vs 19.0%, p&lt;0.001), and osteoporosis (3.5% vs 0.1%, p&lt;0.001). Moreover, cancers other than thyroid cancer (C73.0) were more common in MEN2 patients than in controls (24.1% vs 0.7%, p&lt;0.001). The MEN2 group also had a higher mortality risk, with an incidence rate of 10.1 per 1000 person-years and a hazard ratio of 2.12 (95% CI 1.07-4.19). Conclusions: This study revealed an increase in comorbidities and a higher prevalence of non-thyroid cancer, along with a higher mortality rate, in MEN2 patients with MTC. Our rigorous diagnostic criteria for MEN2, crucial for precise data analysis, led to a smaller patient cohort, reflecting the inherent complexities of rare disease epidemiology. These findings emphasize the need for a nationwide approach to effectively detect, monitor, and manage MEN2 patients and their associated conditions.
Presentation: 6/2/2024