Characteristics of gastric stump cancer: A single hospital retrospective analysis of 262 patients

Identification of prognostic signatures in remnant gastric cancer through an interpretable risk model based on machine learning: a multicenter cohort study

OBJECTIVE

The purpose of this study was to develop an individual survival prediction model based on multiple machine learning (ML) algorithms to predict survival probability for remnant gastric cancer (RGC).

METHODS

Clinicopathologic data of 286 patients with RGC undergoing operation (radical resection and palliative resection) from a multi-institution database were enrolled and analyzed retrospectively. These individuals were split into training (80%) and test cohort (20%) by using random allocation. Nine commonly used ML methods were employed to construct survival prediction models. Algorithm performance was estimated by analyzing accuracy, precision, recall, F1-score, area under the receiver operating characteristic curve (AUC), confusion matrices, five-fold cross-validation, decision curve analysis (DCA), and calibration curve. The best model was selected through appropriate verification and validation and was suitably explained by the SHapley Additive exPlanations (SHAP) approach.

RESULTS

Compared with the traditional methods, the RGC survival prediction models employing ML exhibited good performance. Except for the decision tree model, all other models performed well, with a mean ROC AUC above 0.7. The DCA findings suggest that the developed models have the potential to enhance clinical decision-making processes, thereby improving patient outcomes. The calibration curve reveals that all models except the decision tree model displayed commendable predictive performance. Through CatBoost-based modeling and SHAP analysis, the five-year survival probability is significantly influenced by several factors: the lymph node ratio (LNR), T stage, tumor size, resection margins, perineural invasion, and distant metastasis.

CONCLUSIONS

This study established predictive models for survival probability at five years in RGC patients based on ML algorithms which showed high accuracy and applicative value.

Lymphovascular invasion is associated with poor long-term outcomes in patients with pT1N0-3 or pT2-3N0 remnant gastric cancer: a retrospective cohort study

BACKGROUND

Lymphovascular invasion (LVI) is a poor prognostic factor in various malignancies. However, its prognostic effect in remnant gastric cancer (RGC) remains unclear. We examined the correlation between LVI and disease prognosis in patients with T1N0-3 or T2-3N0 RGC in whom adjuvant chemotherapy was not indicated and a treatment strategy was not established.

METHODS

We retrospectively analyzed patients with T1N0-3 and T2-3N0 RGC who underwent curative surgery at the Kyoto Prefectural University of Medicine between 1997 and 2019 and at the Kyoto Chubu Medical Center between 2009 and 2019.

RESULTS

Fifteen of 38 patients (39.5%) with RGC were positive for LVI. Patients with LVI had a significantly poorer prognosis for both overall survival ([OS]: P = 0.006) and recurrence-free survival ([RFS]: P = 0.001) than those without LVI. Multivariate analyses using the Cox proportional hazards model revealed LVI as an independent prognostic factor affecting OS (P = 0.024; hazard ratio 8.27, 95% confidence interval:1.285-161.6) and RFS (P = 0.013; hazard ratio 8.98, 95% confidence interval:1.513-171.2).

CONCLUSIONS

LVI is a prognostic factor for patients with T1N0-3 or T2-3N0 RGC. Evaluating LVI may be useful for determining treatment strategies for RGC.

Predictive value of positive lymph node ratio in patients with locally advanced gastric remnant cancer

BACKGROUND

Traditional lymph node stage (N stage) has limitations in advanced gastric remnant cancer (GRC) patients; therefore, establishing a new predictive stage is necessary.

AIM

To explore the predictive value of positive lymph node ratio (LNR) according to clinicopathological characteristics and prognosis of locally advanced GRC.

METHODS

Seventy-four patients who underwent radical gastrectomy and lymphadenectomy for locally advanced GRC were retrospectively reviewed. The relationship between LNR and clinicopathological characteristics was analyzed. The survival analysis was performed using Kaplan-Meier survival curves and Cox regression model.

RESULTS

Number of metastatic LNs, tumor diameter, depth of tumor invasion, Borrmann type, serum tumor biomarkers, and tumor-node-metastasis (TNM) stage were correlated with LNR stage and N stage. Univariate analysis revealed that the factors affecting survival included tumor diameter, anemia, serum tumor biomarkers, vascular or neural invasion, combined resection, LNR stage, N stage, and TNM stage (all P < 0.05). The median survival time for those with LNR0, LNR1, LNR2 and LNR3 stage were 61, 31, 23 and 17 mo, respectively, and the differences were significant (P = 0.000). Anemia, tumor biomarkers and LNR stage were independent prognostic factors for survival in multivariable analysis (all P < 0.05).

CONCLUSION

The new LNR stage is uniquely based on number of metastatic LNs, with significant prognostic value for locally advanced GRC, and could better differentiate overall survival, compared with N stage.

The value of lymph nodes ratios in the prognosis of resectable remnant gastric cancer through the retrospective propensity score matching analysis

PURPOSE

Currently, the characteristics and prognosis of remnant gastric cancer (RGC) are not fully understood yet. The present study aimed to describe the details of clinicopathological features of resectable RGC and investigated the factors affecting survival after the curative operation.

METHODS

From Jan. 2006 to Dec. 2015, a total of 118 resectable RGC patients (the RGC group) and 236 age-, sex- and TNM stages-matched resectable gastric cancer (GC) patients (the control group) were recruited retrospectively. Clinicopathological characteristics and overall survival were compared between the two groups.

RESULTS

The overall survival rate was 46.61% for RGC patients compared to 55.08% for control groups (P < 0.01), and the mean overall survival time of RGC patients was 40.23 ± 32.27 months, compared to 55.06 ± 34.29 months in the control group (P = 0.023 after matching). The overall survival (OS) of RGC patients with stage IIb was much worse than IIa (P < 0.001) and similar to IIIa (P = 0.463) and IIIb (P = 0.014). Multivariate Cox proportional hazards model analysis revealed that TNM stage (HR: 3.899, P < 0.001) and lymph nodes ratio (LNR) (HR: 2.405, P = 0.028) were independent prognostic significance to OS.

CONCLUSIONS

The OS of RGC was much worse than GC with similar TNM stages, and LNR might consider a highly reliable indicator to evaluate the prognostic in RGC.

Lymph node distribution in patients with remnant gastric cancer

BACKGROUND

Remnant gastric cancer (RGC) is defined as a carcinoma that develops in the gastric remnant from 5 years after gastrectomy, regardless of the primary gastric disease. The pattern of lymph node dissemination in these patients is not well understood. The present study aims to understand the lymph node distribution of patients with RGC in a single center.

METHODS

In a total of 1380 patients with gastric cancer, between 1998 and 2020, 43 patients operated on for RGC were analyzed. The pattern of lymph node dissemination was evaluated based on the number of dissected lymph node stations, the number of positive lymph node stations, the positivity index at each analyzed station, the number of dissected lymph nodes per patient, and the positivity index per lymph node station.

RESULTS

A mean of 13.0 ± 8.1 lymph nodes were dissected. The incidence of lymph node involvement by dissected station was higher at Stations 19, 11p, 3, 4sb and 7 (50, 40, 37.5, 36 and 31.7%, respectively). Among the positive dissected stations, Station 3 with 52.2%, 4sb with 39.1% and 4sa with 34.8% were the most affected.

CONCLUSION

There was no predilection for lymph node involvement when comparing the lesser and greater gastric curvature. The dissection of Stations 3, 4sb and 4sa is fundamental in surgical treatment with curative purposes. The totalization of gastrectomy with lymphadenectomy of the perigastric and supra-pancreatic stations should be the surgery of choice.

Accuracy of preoperative staging of gastric stump cancer

BACKGROUND

In this study, the accuracy of preoperative staging for gastric stump cancer, which has not been thoroughly investigated since the condition is rare, was investigated using computed tomography and gastroscopic imaging.

METHODS

Between February 1994 and April 2018, 49 patients with gastric stump cancer, following subtotal or total gastrectomy, were reviewed retrospectively. Preoperative diagnoses of clinical T and clinical N categories were compared with post-operative pathological diagnoses (pT and pN categories). Positive predictive values, accuracy, sensitivity and specificity were also evaluated.

RESULTS

The overall accuracy of T staging was 40.8%. The positive predictive value for cT3/T4 was 96.3%, whereas the positive predictive value for cT1/T2 was 72.7%. The overall accuracy for N staging was 61.2%. The positive predictive value of lymph node positive patients was 73.3%. The positive predictive value and sensitivity of over stage II were 96.6% and 84.8%, respectively.

CONCLUSIONS

The accuracy of preoperative diagnosis using both computed tomography and gastroscopy imaging may be feasible for T3/T4 advanced gastric stump cancer, whereas diagnosing T1/2 gastric stump cancer must be carefully considered due to high misdiagnosis rates, relating to depth.

Remnant gastric cancer: An ordinary primary adenocarcinoma or a tumor with its own pattern?

BACKGROUND

Remnant gastric cancer (RGC) is defined as a tumor that develops in the stomach after a previous gastrectomy and is generally associated with a worse prognosis. However, there little information available regarding RGCs and their prognostic factors and survival.

AIM

To evaluate the clinicopathological characteristics and prognosis of RGC after previous gastrectomy for benign disease.

METHODS

Patients who underwent curative resection for primary gastric cancer (GC) at our institute between 2009 and 2019 were retrospectively evaluated. All RGC resections with histological diagnosis of gastric adenocarcinoma were enrolled in this study. Primary proximal GC (PGC) who underwent total gastrectomy was selected as the comparison group. Clinical and pathological data were collected from a prospective medical database.

RESULTS

A total of 41 patients with RGC and 120 PGC were included. Older age (P = 0.001), lower body mass index (P = 0.006), hemoglobin level (P < 0.001), and number of resected lymph nodes resected (LN) (P < 0.001) were associated with the RGC group. Lauren type, pathological tumor-node-metastasis, and perioperative morbimortality were similar between RGC and PGC. There was no difference in disease-free survival (P = 0.592) and overall survival (P = 0.930) between groups. LN status was the only independent factor related to survival.

CONCLUSION

RGC had similar clinicopathological characteristics to PGC. Despite the lower number of resected LN, RGC had a similar prognosis.

The risk scoring system for assessing the technical difficulty of endoscopic submucosal dissection in cases of remnant gastric cancer after distal gastrectomy

BACKGROUND

Endoscopic submucosal dissection (ESD) for remnant gastric cancer (RGC) after distal gastrectomy (DG) is considered technically challenging due to the narrow working space, and severe fibrosis and staples from the previous surgery. Technical difficulties of ESD for RGC after DG have not been thoroughly investigated. This study aimed to develop and validate a risk-scoring system for assessing the technical difficulty of ESD for RGC after DG in a large multicenter cohort.

METHODS

We investigated patients who underwent ESD for RGC after DG in 10 institutions between April 2008 and March 2018. A difficult case was defined as ESD lasting ≥ 120 min, involving piecemeal resection, or the occurrence of perforation during the procedure. A risk-scoring system for the technical difficulty of the procedure was developed based on multiple logistic regression analyses, and its performance was internally validated using bootstrapping.

RESULTS

A total of 197 consecutive patients with 201 lesions were analyzed. There were 90 and 111 difficult and non-difficult cases, respectively. The scoring model consisted of four independent risk factors and points of risk scores were assigned for each as follows: tumor size > 20 mm: 2 points; anastomosis site: 2 points; suture line: 1 point; and non-expert endoscopist: 2 points. The C-statistics of the scoring system for technical difficulty was 0.72.

CONCLUSIONS

We developed a validated risk-scoring model for predicting the technical difficulty of ESD for RGC after DG that can contribute to its safer and more reliable performance.

Prevalence and characteristics of gastric remnant cancer: A systematic review and meta-analysis

The incidence and outcomes of GRC remain variable. Minority published researches have paid attention to the characteristics of GRC. This study aimed to make a systematic review and meta-analysis of the prevalence of GRC, with a focus on characteristics and survival rates of GRC. PubMed, EMBASE, and CENTRAL were searched for related clinical studies. Data were pooled using Stata 11.0, and subgroup and sensitivity analyses were performed if necessary and feasible. Moreover, SPSS (version 19.0) was used for comparing the clinical characteristics of GRC. Twenty studies were selected in this meta-analysis. The results indicated that the pooled prevalence of GRC was 2.6% (95% confidence interval (CI), 2.2-3.0%, p = 0.000). European population and American populations have a higher rate of prevalence of GRC than Chinese populations and Japan. There is no significant difference in histology and the TNM stage between the benign group and the malignant group. The five-year survival rate for GRC cases with benign primary gastric diseases is poorer than the primary gastric diseases malignant. Gastric remnant cancer is not a very rare clinical problem, especially for European and American patients. Active treatment and regular follow-up are conductive to increase 5-years survival rate.

Surgical results of remnant gastric cancer treatment

BACKGROUND

remnant gastric cancer (RGC) develops five years or later after previous resection for benign or malignant lesion. The treatment is performed through completion total gastrectomy (CTG) with radical lymphadenectomy. Some reports consider this procedure may be associated with higher rates of morbidity and mortality.

OBJECTIVE

to evaluate surgical results and survival after CTG in patients with RGC.

METHODS

54 patients who underwent CTG between 2009 and 2019 were included in the study. As a comparison group 215 patients with primary gastric cancer (PGC) who underwent total gastrectomy (TG) in the same period were selected.

RESULTS

among the initial characteristics, age (68.0 vs. 60.5; p<0.001), hemoglobin values (10.9 vs. 12.3; p<0.001) and body mass index (22.5 vs. 24.6; p=0.005) were different between the RGC and PGC groups, respectively. The most frequent postoperative complications were related to pulmonary complications, infection and fistula in both groups. There was a higher incidence of esophagojejunal fistula in the CTG group (14.8% vs 6.5%, p=0.055). Perioperative mortality was higher in RGC patients (9.3% vs. 5.1%), but without significance (p=0.329). Hospital length of stay, postoperative complications graded by the Clavien-Dindo classification, mortality at 30 and 90 days were not different between groups. There was no significant difference in disease-free and overall survival between RGC and PGC groups.

CONCLUSION

despite previous reports, surgical results and survival were similar between groups. Higher risk of esophagojejunal fistula must be considered.

Current controversies in treating remnant gastric cancer: Are minimally invasive approaches feasible?

The incidence of remnant gastric cancer (RGC) is still increasing. Minimally invasive approaches including endoscopic resection, laparoscopic and robotic approaches, and function-preserving gastrectomy have been utilized as curative treatment methods for primary gastric cancer. However, adhesions and anatomical alterations due to previous gastrectomy make the use of minimally invasive approaches complicated and difficult for RGC. Application of these approaches for the treatment of RGC is still controversial. Endoscopic submucosal dissection is a favorable alternative therapy for the resection of early gastric cancer that occurs in the remnant stomach and can prevent unnecessary complications. The majority of retrospective studies have shown that endoscopic submucosal dissection is an effective and oncologically safe treatment modality for RGC. Subtotal gastrectomy could serve as a function-preserving gastrectomy for patients with early RGC and improve postoperative late-phase function. However, there are only two studies that demonstrate the feasibility and oncological efficacy of subtotal gastrectomy for RGC. The non-randomized controlled trials showed that compared to open gastrectomy, laparoscopic gastrectomy for RGC led to better short-term outcomes and similar oncologic results. Because of the rarity of RGC, future multicenter studies are required to determine the indications of minimally invasive treatment for RGC.

A novel prognosis prediction model after completion gastrectomy for remnant gastric cancer: Development and validation using international multicenter databases

BACKGROUND

Examined lymph node counts of remnant gastric cancer patients are often insufficient, and the prognostic ability of tumor-node-metastasis staging is therefore limited. This study aimed to create a simple and universally applicable prediction model for RGC patients after completion of gastrectomy.

METHODS

A 5-year overall survival prediction model for remnant gastric cancer patients was developed using a test dataset of 148 consecutive patients. Model coefficients were obtained based on the Cox analysis of clinicopathological factors. Prognostic performance was assessed with the concordance index (C-index) and decision curve analysis. For internal validation, the bootstrap method and calibration assessment were used. The model was validated using 2 external cohorts from China (First Affiliated Hospital of Fujian Medical University, n = 46) and the United States (Mayo Clinic, n = 20).

RESULTS

Depth of tumor invasion, number of metastatic lymph nodes, distant metastasis, and operative time were independent prognostic factors. Our model's C-index (0.761) showed better discriminatory power than that of the eighth tumor-node-metastasis staging system (0.714, P = .001). The model calibration was accurate at predicting 5-year survival. Decision curve analysis showed that the model had a greater benefit, and the results were also confirmed by bootstrap internal validation. In external validation, the C-index and decision curve analysis showed good prognostic performances in patient datasets from 2 participating institutions. Moreover, we verified the reliability of the model in an analysis of patients with different examined lymph node counts (>15 or ≤15).

CONCLUSION

Utilizing clinically practical information, we developed a universally applicable prediction model for accurately determining the 5-year overall survival of remnant gastric cancer patients after completion of gastrectomy. Our predictive model outperformed tumor-node-metastasis staging in diverse international datasets regardless of examined lymph node counts.

Is there difference between anastomotic site and remnant stump carcinoma in gastric stump cancers?-a single institute analysis of 90 patients

Background

Little has been reported regarding differences between malignancies that develop at the anastomotic site (ASC) and those that develop at the remnant stump (RSC) in gastric stump carcinomas (GSC). The purpose of our study was to compare clinical, pathological and survival characteristics of ASC patients with those of RSC patients.

Methods

Patients who underwent surgery for GSC between January 2005 and December 2017 were analyzed. Of the total 112 patients, 22 patients were excluded from the study due to extensive loss of data. Ninety patients underwent curative resection and were evaluated based on anatomic site at which they developed malignancy, i.e., ASC and RSC. Clinical, pathological and survival characteristics were assessed.

Results

As per Lauren's classification, diffuse and intestinal variety were significantly associated with ASC (P=0.0001) and RSC (P=0.0001) respectively. RSC was associated with lower pT [pT2, 15/33 (45.5%), P=0.0002]. ASC was significantly associated with higher pN [pN3, 30/57 (52.6%), P=0.0013], stage [stage III, 48/57 (84.2%), P=0.0022], positive mesenteric nodes (P=0.006) and poor 3-year survival (10.5% versus 36.4%, P=0.003).

Conclusions

ASC is substantially different than RSC. ASC is more aggressive disease compared to RSC and has different pathophysiology, higher rates of nodal involvement (both primary and mesenteric), presents with higher stage and has significantly poor 3-year survival.

Long-term gastric cancer risk in male smokers with atrophic corpus gastritis

OBJECTIVES

The aim of this study was to evaluate long-term gastric cancer risk in male smokers with and without atrophic gastritis.

MATERIALS AND METHODS

A total of 22,346 elderly male smokers participated in the Helsinki Gastritis Study between the years 1989 and 1993. Serum pepsinogen I (PGI) was measured for the men, and 2,132 men with low PGI (<25 µg/L; a marker of atrophic corpus gastritis) were invited to undergo gastroscopy because of increased gastric cancer risk. Endoscopy was performed to 1,327 men, who were followed up for a median of 13.6 years and a maximum of 25.3 years thereafter. In addition, the gastric cancer risk of men with low PGI was compared to that of the men with normal PGI and to the general Finnish male population of the same age.

RESULTS

Thirty-five cases of gastric cancer were diagnosed in men with gastroscopy during the follow-up. The incidence rate was 1.94 per 1000 patient years. The men with a history of gastric surgery (n = 180) due to a benign cause had even higher gastric cancer incidence (3.2 per 1000 patient-years). Gastric cancer risk was highest in men with marked intestinal metaplasia in primary biopsies. Compared to the general Finnish male population of the same age, the cancer risk was 1.13 times higher in male smokers with normal serum PGI, and 2.43 times higher in men with low serum PGI.

CONCLUSION

In male smokers, atrophic gastritis and intestinal metaplasia increase the risk of gastric cancer.

Clinicopathological characteristics and prognostic factors of remnant gastric cancer: A single-center retrospective analysis of 90 patients

BACKGROUND

The prognosis of remnant gastric cancer (RGC) is significantly poor. However, the mechanism and some clinical features of RGC have not been fully understood and are still under debate.

MATERIALS AND METHODS

From January 2000 to January 2014, 90 RGC patients were enrolled in this retrospective study. Patients were divided into two groups according to primary disease. Clinicopathological features and survival outcomes were compared between two groups.

RESULTS

A total of 34 (37.8%) patients were diagnosed with remnant gastric cancer following benign disease (RGCB) and 56 (62.2%) were diagnosed with remnant gastric cancer following malignant disease (RGCM). The mean time interval from the primary operation to the development of RGC was 12.5 ± 13.3 years in all RGC patients. The mean time interval in RGCB was significantly longer than that in RGCM (P < 0.01). The 1-, 2-, and 3- year overall survival rates of all patients were 56.1%, 38.2% and 33.2%, respectively. Univariate analysis indicated that tumor size, curability, histology type, serosa invasion, nodal involvement and distant metastasis were prognostic factors for RGC. The multivariate Cox regression analysis revealed that distant metastasis was an independent prognostic factor for RGC.

CONCLUSION

RGC occurred earlier in patients with gastrectomy for primary malignant disease than for primary benign disease, even though the primary disease made no difference to the survival of RGC. Nonetheless, RGC patients experienced dismal overall survival. Therefore, early diagnosis plays a significant role in successfully carrying out curative resection and improving the prognosis for RGC.