Metastatic Workup for Melanoma

Melanoma skin cancer ---> metastatic melanoma ---> diagnosis of melanoma

In an attempt to standardize staging workup for melanoma, the National Comprehensive Cancer Network (NCCN) has published guidelines. There are three basic reasons to perform a metastatic workup following the diagnosis of primary cutaneous melanoma: (a) for staging and prognosis, (b) to detect an early metastasis with potential survival benefit, and (c) to avoid morbidity of an extensive surgical procedure by detection of a distant metastasis. The best test for the staging workup still starts with a history (focused review of systems concentrating on constitutional, respiratory, neurologic, hepatic, musculoskeletal, gastrointestinal, skin, and lymphatic systems) and physical examination (total body skin examination, palpation of lymph nodes). Routine imaging and blood studies in asymptomatic patients are low in both sensitivity and specificity. False-positive staging tests are common and lead to more tests and patient distress. SLNB represents the best baseline staging test, with both relatively high sensitivity and specificity in patients at significant risk for metastasis. The ability to detect stage IV disease with routine studies is small if the SLNB is negative. Ultrasound is perhaps the most sensitive noninvasive test to detect small nodal metastases. However, the sensitivity and specificity of ultrasound and PET scanning are inferior to tissue diagnosis with SLNB.