Almost 25% of patients had hereditary medullary thyroid cancer and of those, 10/53 were identified by screening; most had a moderate-risk gene mutation causing the cancer. Hereditary cases were diagnosed at a younger age, and those diagnosed by screening presented at an earlier disease stage. Patients with hereditary medullary thyroid cancer diagnosed by screening had similar overall survival to that of the general population. Patients with both sporadic and hereditary medullary thyroid cancer diagnosed by symptoms had a decreased survival compared to the general population. However, the most important predictors of disease- specific survival were younger age at diagnosis and lack of spread beyond the thyroid and lymph node involvement was the most important predictor of biochemical cure, which was important for disease-specific survival.
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
Patients diagnosed with early-stage medullary thyroid cancer, including patients with hereditary medullary thyroid cancer detected by screening, have similar survival to that of the general population. However, patients that present with spread to the lymph nodes rarely achieve a biochemical cure, which confirms prior studies. Sharing this information with patients who present with spread to the lymph nodes can temper expectations for biochemical cure but provide reassurance about long-term survival even in the presence of persistently elevated calcitonin levels.
— Melanie Goldfarb MD, MS, FACS, FACE