Metastasectomy in colorectal cancer patients with concurrent lung and liver metastasis: Trends in utilization and impact on survival.

Abstract

53 Background: Colorectal cancer (CRC) frequently presents with concurrent metastasis to the lung and liver. Metastasectomy may offer extended disease control in a select group of patients but its utilization is unknown. We aimed to investigate the trends in utilization of metastasectomy in CRC patients with concurrent lung and liver metastasis and explore its impact on survival. Methods: We queried the National Cancer Database and identified stage 4 CRC patients with concurrent lung and liver metastasis between 2010 – 2016 and categorized them into those that underwent metastasectomy vs. those that did not. Categorical variables were compared using the chi-square test, and statistically significant factors were included in multivariable logistic regression analysis. In addition, 1:2 propensity score matching was performed, and a multivariable Cox regression model was used to define survival predictors among matched cohorts. The Kaplan-Meier method was used to estimate the median survival. Results: Out of total 77,719 stage 4 CRC patients, 10,106 (13.0%) patients had concurrent lung and liver metastasis. Six percent (n = 630) of these patients underwent metastasectomy of both sites. Patients that underwent metastasectomy were more likely to be younger (< 50 years; p = 0.009), female ( p < 0.001), and White ( p = 0.01). These patients were also more likely to have right-sided CRC ( p = 0.001) and had resection of the primary site (p < 0.001). Additionally, they were more likely to have private health insurance ( p < 0.001) and receive treatment at an academic center ( p = 0.03). On adjusted multivariable analysis, female gender, care at an academic center, primary tumor resection and receiving chemotherapy were associated with the metastasectomy group. We did not find a statistically significant difference between comorbidity score, KRAS status and microsatellite status between the 2 groups. In the matched analysis, overall survival (OS) was significantly improved for patients who underwent metastasectomy (23.2 months) vs. those who did not (11.6 months, p < 0.001). On multivariable analysis, this difference remained, and metastasectomy was an independent predictor of better OS (HR 0.74 [0.65-0.85], p < 0.001). Conclusions: The utilization of metastasectomy in concurrent lung and liver metastasis is low. It is more frequently used in younger, female and White patients, as well as in patients treated at an academic center. Metastasectomy is independently associated with improved overall survival in patients eligible for such an approach.