Sporadic medullary thyroid carcinoma (MTC) is a rare cancer with widely varying clinical outcomes, and the influence of age at diagnosis on prognosis remains unclear. We examined 432 patients with sporadic MTC, followed for a median of 7.4 years, and stratified them into two age-based groups: under 65 years (group A, n = 338, 78.2%) and 65 years or older (group B, n = 94, 21.8%). No notable differences in baseline characteristics were observed between the groups, though younger patients had a significantly longer median follow-up. During the study, 41 patients (9.5%) died from the disease, with similar mortality rates in both age groups. Nonetheless, survival analysis revealed that younger patients had a longer overall survival compared to older patients [HR 2.5, 95% CI: 1.27–4.94, p < 0.01]. Among those who died, disease severity at diagnosis and treatment strategies were comparable between age groups. These findings suggest that while age at diagnosis does not appear to influence clinical or pathological features of sporadic MTC, younger patients tend to have a longer survival despite similar rates of disease-related mortality.
