Stage-IV Melanoma and Pulmonary Metastases: Factors Predictive of Survival

We reviewed a contemporary, single-institution experience to evaluate the natural history of stage-IV melanoma metastatic to the lung and identify factors predictive of survival.

A search of our prospective database was performed to identify patients with stage-IV melanoma and pulmonary metastases as the initial disease site; only patients seen at our institution prior to developing stage-IV disease and in whom treatment response was available were included. Patients’ demographic, clinical, and treatment variables were recorded. Cox regression was used to identify factors independently predictive of survival.

The study cohort was comprised of 122 patients. Median survival was 14 months (5-year survival of 8%). Clinical factors at time of diagnosis of stage IV independently predictive of survival were a solitary pulmonary metastasis (HR 2.7, CI 1.6–4.4, P<0.0005) and absence of extra-pulmonary disease (HR 1.9, CI 1.2–3.1, P = 0.01). Among treatment factors, only metastasectomy was independently predictive of survival (HR 0.42, CI 0.21–0.87, P = 0.02). Of the patients, 26 (21%) underwent metastasectomy, with a median survival of 40 months compared with 13 months in patients not selected for surgical treatment. Of these 26, 23 (88%) experienced recurrence at a median of 5 months after the procedure. No survival difference was seen between responders and non-responders to systemic therapy (P = 0.55).

In stage-IV melanoma with pulmonary metastases, a solitary metastasis and absence of extra-pulmonary disease are predictive of survival. While these factors are often present in patients selected for pulmonary metastasectomy, this independently predicts survival. However, response to systemic therapy does not correlate with a survival difference.