OBJECTIVETo compare clinicopathological features and prognosis between patients with carcinoma in the remnant stomach (CRS) and with gastric cancer, and to investigate the prognostic factors in CRS patients.

METHODSA retrospective cohort study was performed on clinicopathological data of 96 CRS patients (CRS group) and selected 440 patients with gastric cancer (GC group) treated at Harbin Medical University Cancer Hospital from January 1977 to December 2017.

INCLUSION CRITERIA(1) undergoing gastrectomy; (2) diagnosed with CRS or gastric cancer through electronic gastroscopies and pathology; (3) without preoperative neoadjuvant radiotherapy or chemotherapy; (4) complete clinicopathological and follow-up data. The patients who died of other reasons or were lost during follow-up were excluded. Chi-square test and independent samples t-test were used to determine differences in clinicopathological factors between two groups. Survival analysis was conducted using the Kaplan-Meier method, and Log-rank test was used to compare survival difference between two groups. The prognosis of CRS patients was analyzed using Cox proportional hazards regression model.

RESULTSAs compared to GC group, CRS group had a higher proportion of female [30.2%(29/96) vs. 13.2%(58/ 440), χ=14.095, P=0.000], younger age [(56.4±10.1) years vs. (60.0±9.9) years, t=2.838, P=0.005], more distant metastasis and local organ infiltration [25.0%(24/96) vs. 16.1%(71/440), χ=4.246, P=0.039; 64.6% (62/96) vs. 24.5% (108/440), χ=58.331, P=0.000], lower prognostic nutritional index [(48.0±6.7) vs. (50.4±6.9), t=3.093, P=0.002], lower serum hemoglobin level [(115.0±24.7) g/L vs. (127.9±24.6) g/L, t=4.634, P=0.000], lower serum albumin level [(40.0±4.9) g/L vs. (41.2±5.0) g/L, t=2.038, P=0.042], and earlier occurrence of symptoms [(1.9±1.4) months vs. (3.7±3.2) months, t=5.431, P=0.000]. However, there were no statistically significant differences in TNM staging, postoperative hospital stay, and total hospitalization days between the two groups (all P>0.05). During follow-up, 24(25.0%) patients developed recurrence or distant metastasis and 68 (70.8%) patients died of tumor progression in CRS group, while 71(16.1%) patients developed recurrence or distant metastasis and 378(85.9%) patients died of tumor progression in GC group. The 5-year survival rate of CRS patients was 23.4%, which was higher than 15.0% of gastric cancer patients (P=0.032). Univariate analysis showed that the CRS patients with radical operation (P=0.000), earlier TNM stage (P=0.000), non-distant metastasis (P=0.022), serum hemoglobin level >130 g/L(P=0.013), and serum album level >40 g/L (P=0.042) had better prognosis. Multivariate analysis, enrolling above 5 factors, showed that TNM staging (HR=2.363, 95%CI: 1.478-3.776, P=0.000) and serum hemoglobin level >130 g/L(HR=0.449, 95%CI: 0.244-0.827, P=0.010) were independent factors influencing prognosis of CRS patients.

CONCLUSIONSAlthough CRS patients have better prognosis than gastric cancer patients, but local organ invasion and distant metastasis occurs more readily. TNM staging and serum hemoglobin level are independent prognostic factors for CRS patients.