A Decade of Melanomas: Identification of Factors Associated with Delayed Detection in an Academic Group Practice

BACKGROUND Melanoma incidence is increasing, but the effect of various clinical factors on tumor stage is unclear. OBJECTIVE To review histologic and clinical features of melanomas diagnosed in our group over a 10-year period to determine trends in diagnosis and lesion derivation, predictive value of clinical lesion size, and effect of physician and patient concerns before biopsy. METHOD Relevant pathology reports and physician clinic notes were reviewed for 572 melanomas. RESULT From 1999 to 2008, melanoma biopsies increased significantly more than nevus biopsies and patient visits. Melanomas predominantly (81%) arose de novo, with remaining lesions as likely to arise from common as dysplastic nevi. Melanomas were detected at twice the rate, and at earlier stage, in established as in new patients. Clinical size of invasive melanomas was related to lesion depth. For 64% of melanomas, patient and physician concern drove the decision to biopsy, whereas 1.4% of melanomas were biopsied only for patient concern. CONCLUSION The increase in melanoma diagnoses was largely due to increases in cases of lentigo maligna on the head and neck. Delayed detection was associated with location on trunk and extremities, new patient status, patient concern before biopsy, and physician suspicion of nonmelanoma skin cancer.