Routine restaging PET/CT and detection of initial recurrence in sentinel lymph node positive stage III melanoma.

Background: Follow-up of patients with sentinel lymph node-positive stage III melanoma uses history, physical exam, and cross-sectional imaging. The aim of this study was to evaluate positron emission tomographic (PET)/computed tomographic (CT) scans in the detection of recurrence.

Methods: From 2003 to 2009, a single-institution prospective database of all cutaneous melanoma patients was used to identify sentinel lymph node-positive stage III patients with disease-free survival >1 year and 1 restaging PET/CT scan.

Results: Thirty-eight patients were identified, with a median follow-up period of 27.5 months. Seven (18%) developed recurrence (median time to recurrence, 25 months). Recurrences were detected as follows: 3 by patients, 1 by physician, 1 by PET/CT scan and lactate dehydrogenase, 1 by PET/CT scan, and 1 by brain magnetic resonance imaging. One hundred eight follow-up PET/CT scans were performed. Two of 38 patients had asymptomatic metastases detected by routine restaging PET/CT scan, and there were 9 scans with false-positive results.

Conclusions: With short follow-up, the utility of routine PET/CT scans in identifying unsuspected recurrence in patients with sentinel lymph node-positive stage III melanoma appears minimal.