182P - Cytoreductive surgery and chemotherapy in metastatic gastric adenocarcinoma: A population-based study

Background

Gastric adenocarcinoma (GA) with peritoneal carcinomatosis is associated with poor prognosis with median overall survival surfacing under the one-year mark. The treatment of gastric cancer remains controversial. Using hyperthermic intraperitoneal chemotherapy (HIPEC) in combination with cytoreductive surgery may help reduce mortality rates. This study attempted to investigate treatment modalities available for metastatic gastric adenocarcinoma.

Methods

We extracted all adult patients with intestinal-type gastric adenocarcinoma with 7^th edition AJCC M1 stage (2010-2015) using the Surveillance Epidemiology and End Results (SEER) database. Patients with extra-peritoneal metastasis were excluded. We stratified patients into four different groups: surgery, chemotherapy, surgery and chemotherapy, and no surgery/no chemotherapy. Kaplan-Meier and Cox proportional hazard regression models were utilized to access overall survival (OS) and cancer-specific survival (CSS).

Results

A total of 243 patients were identified. The median (OS) of the entire cohort was 11 months. Patients who received both chemotherapy and surgery, chemotherapy alone, and surgery alone had higher median (OS) compared to no treatment [19, 13, and 6 months, respectively, vs 3 months, p<0.001], as well as a higher (CSS) (p<0.0001). Patients who received no therapy had a statistically significant risk of overall mortality compared to the chemotherapy and surgery group [HR= 9.28 (5.40 -15.94). p<0.001], and compared to other treatment groups (p<0.001). N3B Stage was a significant risk factor for (OS) and (CSS) [HR= 2.69 (1.23 -5.78), p<0.013]. Table: 182P

Median overall survival

Conclusions

The combined usage of surgery and chemotherapy significantly improved the median overall and cancer-specific survival for (GA) patients.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.