Satellite and In-Transit Metastatic Disease in Melanoma Skin Cancer: A Retrospective Review of Disease Presentation, Treatment, and Outcomes

BACKGROUND: Satellitosis and in-transit metastases (SITM) are uncommon in cutaneous melanoma and are associated with poor prognosis. However, the disease- and treatment-specific variables that predict outcomes among patients with SITM are poorly defined. OBJECTIVE: To identify factors that predict prognosis among patients with SITM. MATERIALS AND METHODS: Retrospective chart review of patients treated for melanoma at a large academic medical center in central Pennsylvania between 2000 and 2012. Patients with pathology reports containing "satellite lesions" or "in-transit metastases" were selected for analysis. Data were collected regarding tumor stage, the timing of SITM discovery, treatment, recurrence-free survival after SITM discovery, and overall survival (OS). RESULTS: We identified SITM in 32 (1.9%) of 1,650 patients with pathology-diagnosed melanoma over the study period. Reduced recurrence-free survival after SITM discovery was associated with higher pathologic stage, metastatic disease, lymph node dissection, and use of adjuvant chemotherapy. Reduced OS was associated with higher T, N, M, and overall prognostic stage; positive surgical margins; disease recurrence; and SITM on initial presentation. CONCLUSION: Our data support previous findings that higher stage disease confers a worse prognosis among patients with SITM. Patients with SITM on initial presentation had worse outcomes, suggesting SITM is indicative of more aggressive disease.