Role of Neoadjuvant Chemotherapy Before Simultaneous Resection of Colon Cancer and Liver Metastases: A Propensity-Score Matched Analysis.

BACKGROUND

There has been a controversy about the optimal management of colorectal liver metastases (CLM). Both upfront surgery and neoadjuvant chemotherapy are viable options for CLM. The present study aimed to assess the short-term and survival outcomes of neoadjuvant chemotherapy before simultaneous resection of primary colon cancer and liver metastases.

METHODS

This retrospective cohort study used data from the National Cancer Database (2015-2019) on patients with primary colon cancer and synchronous liver metastases. The main exposure was neoadjuvant chemotherapy before simultaneous resection of colon cancer and hepatic metastases. Propensity-score matching was used to match patients who had upfront surgery without neoadjuvant chemotherapy with patients who received neoadjuvant chemotherapy. The primary outcome was 5-year overall survival (OS). Secondary outcomes included hospital stay, 30-day and 90-day mortality, 30-day unplanned readmission, conversion to open surgery, surgical margins, and disease downstaging.

RESULTS

Overall, neoadjuvant chemotherapy was given to 38.3% of 4060 patients. After matching, 1446 patients (53% male) were included; 482 were in the neoadjuvant group and 964 were in the no-neoadjuvant group. Neoadjuvant chemotherapy was associated with a longer restricted mean OS (46.7 vs. 40.6 months, P < .001) and significantly lower rates of 90-day mortality (3% vs. 6.5%, P = .008), 30-day unplanned readmission (4.8% vs. 8.8%, P = .002), positive surgical margins (6.5% vs. 15.1%, P < .001), and administration of adjuvant therapy (47.3% vs. 79.5%, P < .001). The 2 groups were comparable in hospital stay, 30-day mortality, and number of examined lymph nodes.

CONCLUSIONS

Giving neoadjuvant chemotherapy before simultaneous resection of colon cancer and hepatic metastases was associated with extended mean OS and reduced rates of 90-day mortality, 30-day unplanned readmission, and positive surgical margins.