Impact of Hepatic Metastasectomy in the Multimodal Treatment of Metastatic Breast Cancer

Background: Surgical management of hepatic metastases in patients with stage IV breast cancer remains controversial. The purpose of this study was to examine the impact of hepatic metastasectomy on long-term outcomes. Methods: The 2004-2015 National Cancer Database was queried for all patients diagnosed with stage IV breast cancer with metastases isolated to the liver. Patient demographics, disease-, treatment- and outcome-related data were analyzed. Results: Of 2,895 patients, only 90 (3.1%) underwent hepatic resection. Compared to patients who did not undergo metastasectomy, patients treated with metastasectomy tended to be younger (52 ± 12.7 versus 59.2 ± 14.6; P < 0.001) and have private insurance (74.4% versus 45.3%; P < 0.001). Independent predictors of metastasectomy included younger age (OR 0.98; CI 0.96-0.99; P = 0.01), lobular carcinoma (OR 2.26; CI 1.06-4.82; P = 0.03), and prior surgery of the primary site (partial mastectomy (OR 6.96; CI 3.47-13.95; P < 0.001) or total mastectomy (OR 5.74; CI 3.06-10.76; P < 0.001)). Compared to no metastasectomy, hepatic metastasectomy was independently associated with a 37% reduction in the risk of death (HR 0.63; CI 0.44-0.91; P = 0.01). Conclusions: Stage IV breast cancer with metastases to the liver is rare and few patients undergo hepatic resection. However, in this select patient population, hepatic metastasectomy was associated with a significant survival advantage when included in the multimodal treatment of synchronous stage IV breast cancer.