Prolonged overall survival after pulmonary metastasectomy in patients with breast cancer

Background: We investigated whether overall survival (OS) in patients with primary breast cancer (BC) is prolonged by pulmonary metastasectomy and which prognostic criteria may facilitate the decision in favor of thoracic surgical intervention.

Methods: We assessed the median OS of 81 women after resection of pulmonary primary BC metastases by means of Kaplan-Meier estimators. Statistical interferences regarding prognostic factors were based on univariate log-rank tests and multivariate Cox proportional hazards regression. Matched patients who had not undergone resection from the Munich Tumor Registry served as controls.

Results: Between 1982 and 2007, 81 patients were recruited prospectively. In 81.5% of the patients R0 resection was achieved, which was associated with significantly longer median OS than occurred after R1 or R2 resection (103.4 months versus 23.6 months versus 20.2 months, respectively; p<0.001). Multivariate analysis revealed R0 resection, number (n≥2), size (≥3 cm), and estrogen receptor (ER) and/or progesterone receptor (PR) positivity of metastases as independent prognostic factors for long-term survival. Presence of metastases in mediastinal and hilar lymph nodes correlated with decreased survival only in the univariate analysis (32.1 versus 103.4 months; p=0.095). Matched pair analysis confirmed that pulmonary metastasectomy significantly improved survival.

Conclusions: OS in patients with isolated pulmonary primary BC metastasis is prolonged by metastasectomy. Patients with multiple pulmonary lesions or metastases with negative hormone receptor (HR) status are at greater risk of disease relapse and should be followed closely. Moreover, additive treatment tailored to the biological subtype defined by HR expression should be considered for this group.