Evaluation of staging chest radiographs and serum lactate dehydrogenase for localized melanoma

Radiographic and laboratory evaluations are often routinely used in the initial work-up for melanoma.

To examine the yield of a chest radiograph and serum lactate dehydrogenase (LDH), in the work-up for newly diagnosed localized melanoma.

Patients with a new diagnosis of localized invasive melanoma were entered into a prospective database. The status of the chest radiograph, LDH, and sentinel lymph node (SLN) was assessed.

Two-hundred-twenty-four patients were entered into the study and 210 had chest radiograph data for analysis. The true positive chest radiograph rate, defined as the percent of chest radiographs interpreted as "positive or equivocal possibly melanoma related" with subsequent confirmed melanoma metastases, was 0%. The false positive chest radiograph rate, defined as the percent of chest radiographs interpreted as "positive or equivocal possibly melanoma related" with melanoma metastases excluded based on previous or subsequent studies or other known medical conditions, was 7%. Ninety-six patients (melanoma> or =1 mm) had LDH results for analysis. Elevations in LDH were found in 15% and did not lead to detection of occult disease in any patients. Seventy-seven patients underwent SLN biopsy. A positive SLN did not correlate with abnormal chest radiograph or LDH.

Low yield, high rate of false-positive tests and lack of significant impact of early detection of metastases on survival argue that chest radiographs and serum lactate dehydrogenase should probably not be accepted into routine clinical practice in patients with clinically localized melanoma in the absence of data supporting their use.