What is the prognosis of Merkel cell carcinoma (MCC)?
Merkel cell carcinoma (MCC) is a deadly disease with a poor outlook for survival. Local recurrence occurs in 44% of patients; multiple local recurrences occur in 15%. These recurrences usually happen within 5 months after the primary lesion is treated. About 15% of patients have palpable nodes at the time of diagnosis. Lymph node metastases eventually develop in 55% of patients, and distant metastases develop in 34%. Most metastases occur before the eighth month after diagnosis.
@krista The areas where metastases are most likely to occur are the liver, bone, brain, and lung. The presence of distant metastases is the only factor that is consistently predictive of the outcome. The mean time to death after the discovery of distant metastases is 5 months. Mortality rates for patients with distant metastases are 75-100%. In patients without distant metastases, mortality rates are 4%.