This study analyzed tumor doubling times (TDT) in four cases of primary cutaneous melanoma with delayed diagnoses and their corresponding metastases. The median/mean TDT for primary melanomas was 94/144 days (range: 50–377 days), while metastatic melanomas exhibited a significantly faster TDT of 33/64 days (range: 8–212 days) (P = 0.01).
