The Incidence and Risk Factors for Metachronous Gastric Cancer in the Remnant Stomach after Gastric Cancer Surgery

Survival outcome and prognostic factors of remnant gastric cancer: a propensity score-matched analysis

Background

Studies on survival and prognostic factors in individuals with remnant gastric cancer (RGC) after gastric cancer (GC) are rare. It is debatable whether prognosis of RGC after GC is worse than that of only primary GC (OPGC). The objective of this study is to compare the survival outcomes between post-GC RGC and OPGC undergoing surgical resection and to identify the prognostic factors of disease-specific survival (DSS) for RGC.

Methods

We retrospectively collected data from the Surveillance, Epidemiology, and End Results (SEER) database among patients who underwent GC surgery in 1988-2020. Propensity score matching (PSM) was conducted to balance baseline characteristics. Kaplan-Meier (KM) survival analysis was performed to compare their overall survival (OS) and DSS. Multivariable Cox analyses were performed to identify the independent prognostic factors of DSS for post-GC RGC by estimating hazard ratios (HRs) with 95% confidence intervals (CIs).

Results

There were 76 patients with RGC and 32,763 patients with OPGC included and analyzed. After balancing the baseline characteristics by PSM, no significant difference existed between OPGC and RGC groups in both OS (P=0.65) and DSS (P=0.28). Fixed-time analyses also showed no difference between the two groups for the 5-year (60.0%, RGC vs. 53.3%, OPGC, P=0.38) and 10-year DSS (56.7%, RGC vs. 48.3%, OPGC, P=0.34). Multivariable analysis revealed that area of lower income ($75,000+ vs. <$55,000, HR =0.21, 95% CI: 0.05-0.89, P=0.03), cardiac tumor [middle vs. cardia, HR =0.16, 95% CI: 0.03-0.77, P=0.02; distal vs. cardia, HR =0.10, 95% CI: 0.02-0.58, P=0.01; not otherwise specified (NOS) vs. cardia, HR =0.11, 95% CI: 0.03-0.51, P=0.004], deeper invasion (T3-4 vs. Tis-2, HR =5.19, 95% CI: 1.21-22.15, P=0.03), higher grade (G3 vs. G1-2, HR =7.35, 95% CI: 1.41-38.48, P=0.02) and not receiving chemotherapy (yes vs. no/unknown, HR =0.16, 95% CI: 0.04-0.60, P=0.007) were independent risk factors for postsurgical DSS in patients with post-GC RGC.

Conclusions

The prognosis of post-GC RGC was comparable to that of OPGC following surgical resection. The independent prognostic factors for RGC are similar to those established for OPGC. Our findings suggest that RGC following first GC might be the same entity to OPGC and curative resection should be considered in selected patients.

Incidence and risk of remnant gastric cancer after gastrectomy for gastric cancer: a population-based study from the SEER database

BACKGROUND

Gastric cancer (GC) constitutes a major global health problem, of which remnant gastric cancer (RGC) occurs less frequently. The rate of RGCs after gastrectomy for GC is increasing recently due to improved survival and screening, however, their incidence and risk have not been reported in the U.S.

POPULATION

The objective of this study was to evaluate the incidence and elevated risk of RGC after GC gastrectomy in this population, and to identify the risk factors.

METHODS

Patients underwent gastrectomy for first primary GC in 2000-2015 and those who developed RGC were identified from Surveillance, Epidemiology and End Results (SEER) database. Fine-Gray regression was used to estimate the cumulative incidence and to identify risk factors. Standardized incidence ratios (SIRs) were calculated by Poisson regression to compare the risk with the general population.

RESULTS

Among 21,566 patients included in the cohort, 227 developed RGC. The 20-year cumulative incidence of RGC was 1.88%. Multivariate analysis revealed that older age, invasion depth, male sex, marital status, and lower income are independent risk factors for RGC development. SIR was 7.70 overall and > 4.5 in each stratum.

CONCLUSIONS

Cumulative incidence and risk for RGCs increased continuously in patients underwent GC gastrectomy. Close and lifelong endoscopy surveillance should be recommended for patients who received GC gastrectomy, especially those with high-risk factors.

Risk assessment of metachronous gastric cancer development using OLGA and OLGIM systems after endoscopic submucosal dissection for early gastric cancer: a long-term follow-up study

BACKGROUND

Metachronous gastric cancer (MGC) may develop in patients undergoing curative endoscopic submucosal dissection for early gastric cancer. As gastritis and intestinal metaplasia are notable precursors to gastric cancer, we assessed MGC risk using the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastric Intestinal Metaplasia assessment (OLGIM) systems.

METHODS

This retrospective cohort study classified the OLGA and OLGIM stages for 916 patients who had undergone endoscopic submucosal dissection for early gastric cancer between 2005 and 2015. MGC development was followed up until 2020 and risk factors were evaluated using the Cox proportional hazards regression analysis.

RESULTS

During a median follow-up of 94 months, MGC developed in 120 subjects. OLGA stages II ~ IV were significantly associated with increased MGC risk (hazard ratio [HR] 1.83, 95% confidence interval [CI] 1.05-3.19; HR 2.31, 95% CI 1.22-4.38; HR 2.36, 95% CI 1.16-4.78) in multivariable analysis, even after adjusting for the well-known positive predictor of Helicobacter pylori eradication. OLGIM stages II ~ IV also showed significant association (HR 2.86, 95% CI 1.29-6.54; HR 2.94, 95% CI 1.34-6.95; HR 3.64, 95% CI 1.60-8.29). 5-year cumulative incidence increased with each stage. Helicobacter pylori-eradicated patients with OLGIM stages 0 ~ II had significantly less MGC than non-eradicated patients (4.5% vs 11.8%, p = 0.022), which was not observed with OLGIM stages III ~ IV.

CONCLUSIONS

High OLGA and OLGIM stages are independent risk factors for metachronous gastric cancer, with the OLGIM staging system being a better predictor. Patients with OLGIM stages 0 ~ II are a subgroup that may benefit more from Helicobacter pylori eradication.

Sex-based differences in histology, staging, and prognosis among 2983 gastric cancer surgery patients

BACKGROUND

Few studies have been conducted on sex differences in the incidence, pathophysiology, and prognosis of gastric cancer (GC).

AIM

To analyze the differences in GC characteristics according to sex in patients who underwent surgical treatment for GC.

METHODS

A total of 2983 patients diagnosed with gastric adenocarcinoma who received surgical treatment at the Seoul National University Bundang Hospital between 2003 and 2017 were included. Baseline clinicopathological characteristics, histologic type of GC, overall and GC-specific survival rates, and associated risk factors were analyzed.

RESULTS

Among the 2983 patients, 2005 (67.2%) and 978 (32.8%) were males and females, respectively. The average age of the female group (59.36 years) was significantly younger than that of the male group (61.66 years; P < 0.001). Cancer of the gastric body (P < 0.001) and diffuse-type histology (P < 0.001) were more common in females than in males. This trend was more prominent in females younger than 60 years of age, with a significantly higher proportion of diffuse-type cancer than in the male group. Regardless of sex, diffuse-type GC was more common in younger patients, and the proportion of intestinal-type GC increased with age. The overall survival rate was significantly higher in females (P < 0.001). However, this difference disappeared for GC-specific survival (P = 0.168), except for the poor GC-specific survival rate in advanced-stage cancer (stage III or above) in females (P = 0.045). The risk factors for GC-related mortality were older age, upper location of GC, and diffuse- or mixed-type histology. In terms of comorbidities, more males died from diseases other than GC, including other malignancies such as lung cancer, hepatocellular carcinoma, and pancreatic cancer, and respiratory diseases such as interstitial lung disease and chronic obstructive pulmonary disease, while there were relatively more cardiovascular or cerebrovascular deaths in females.

CONCLUSION

Sex-based differences in GC were observed in clinicopathological features, including age at diagnosis, tumor location, histologic type, survival rate, and comorbidities.