Abstract 182P
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 7th 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
| N | Events | Median survival | 95% CI | |
| Overall Survival (OS) | ||||
| No treatment administered | 56 | 54 | 3 | (2- 5) |
| Chemotherapy alone | 91 | 86 | 13 | (11- 17) |
| Surgery alone | 32 | 29 | 6 | (3- 16) |
| Both chemotherapy and surgery | 64 | 55 | 19 | (16- 29) |
| Cancer-Specific Survival (CSS) | ||||
| No treatment administered | 56 | 53 | 3 | (2- 5) |
| Chemotherapy alone | 87 | 75 | 13 | (11-18) |
| Surgery alone | 30 | 21 | 15 | (4-43) |
| Both chemotherapy and surgery | 62 | 49 | 19 | (16-31) |
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.
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