Staging for Remnant Gastric Cancer: The Metastatic Lymph Node Ratio vs. the UICC 7th Edition System

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.

Positive lymph node ratio is an important index to predict long-term survival for advanced esophageal squamous carcinoma patients (II∼III) with R0 resection--a SEER-based analysis

Background

Esophageal squamous carcinoma (ESCC) is one of the most malignant cancers in the world due to nodal metastasis. Therefore, a reasonable nodal staging system is extremely important for further treatment strategies. Recently the positive lymph node ratio (PLNR) is an important prognostic factor in various solid tumors.

Method

In this study, we investigated the clinical significance of the PLNR in stage II∼III ESCC patients. We collected the pathological characteristics of 272 stage II∼III ESCC patients from the SEER database from 2004-2016. ROC curves were used to calculate the best cutoff value of the PLNR; Pearson's Chi-square (χ2) and Fisher's exact probability tests were used to compare the clinical baseline and characteristics of patients. For continuous variables, Student's t-test and ANOVA were performed to evaluate statistical significance. Clinical outcomes were estimated by using the Kaplan‒Meier method and log-rank test. Furthermore, univariate and multivariate Cox regression models were utilized to analyze independent prognostic factors of ESCC patients.

Results

Consequently, advanced ESCC patients were effectively stratified into two groups by prognosis using a PLNR cutoff value of 0.15 (P value = 0.04). The median survival time of patients with PLNR <0.15 (n = 145) was much higher than that of patients (n = 127) in the PLNR ≥0.15 group (20.0 vs. 13.0 months, P value < 0.0001). Notably, the PLNR significantly predicted the prognosis of ESCC patients with stage N1 (P value 0.01) and stage III (P value < 0.001) disease. The multivariate Cox proportional hazard model showed that T stage (HR 1.33, 95 % CI 0.97-1.82), tumor size >45 mm (HR 1.32, 95 % CI 1.02-1.70), N stage (HR 1.41, 95 % CI 0.98-2.01) and PLNR ≥0.15 (HR 1.35, 95 % CI 0.87-1.74) were independent risk factors for prognostic prediction in ESCC patients. Meanwhile, 117 II∼III ESCC patients from Shaanxi Provincial People's Hospital shown that the overall survival with a PLNR <0.15 (n = 96) was significantly longer than that with a PLNR ≥0.15 (n = 21) .

Conclusions

The PLNR is useful for accurately predicting clinical outcomes and determining postoperative strategies.

Does gastric stump cancer really differ from primary proximal gastric cancer? A multicentre, propensity score matching-used, retrospective cohort study

BACKGROUND

Although the location of proximal cancer of the remnant stomach is the same as that of primary proximal cancer of the stomach, its clinical characteristics and prognosis are still controversial.

AIM

To evaluate the clinicopathological features and prognosis factors of gastric stump cancer (GSC) and primary proximal gastric cancer (PGC).

METHODS

From January, 2005 to December, 2016, 178 patients with GSC and 957 cases with PGC who received surgical treatment were enrolled. Patients in both groups underwent 1:1 propensity score matching analysis, and both clinical and pathological data were systematically collected for statistical purposes. Quality of life was evaluated by the C30 and STO22 scale between GSC-malignant (GSC following gastric cancer) and GSC-benign (GSC following benign lesions of the stomach).

RESULTS

One hundred and fifty-two pairs were successfully matched after propensity score matching analysis. Of the 15 demographic and pathological variables collected, the analysis further revealed that the number of lymph nodes and positive lymph nodes were different prognostic and clinicopathological factors between PGC and GSC. Univariate and multivariate analyses showed that gender, differentiation degree and tumor-node-metastasis stage were independent risk factors for patients with GSC. Gender, vascular invasion, differentiation degree, depth of infiltration, positive lymph nodes, and tumor-node-metastasis stage were independent risk factors for patients with PGC. The 5-year overall survival and cancer-specific survival of patients with GSC were significantly lower than those in the PGC group, the scores for overall quality of life in the GSC-malignant group were lower than the GSC-benign, and the differences were statistically significant.

CONCLUSION

The differences in clinicopathological characteristics between GSC and PGC were clarified, and PGC had a better prognosis than GSC.

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.

Appraisal of gastric stump carcinoma and current state of affairs

Gastric stump carcinoma, also known as remnant gastric carcinoma, is a malignancy arising in the remnant stomach following gastrectomy for a benign or malignant condition. Enterogastric reflux and preexisting risk factors in a patient with gastric cancer are the major contributors to the development of gastric stump carcinoma. The occurrence of gastric stump carcinoma is time-dependent and seen earlier in patients operated on for malignant rather than benign diseases. The tumor location is predominantly at the anastomotic site towards the stomach. However, it can occur anywhere in the remnant stomach. The pattern of lymph node involvement and the type of surgery required is distinctly different compared to primary gastric cancer. Gastric stump carcinoma is traditionally considered a malignancy with a dismal outcome. However, recent advances in diagnostic and therapeutic strategies have improved outcomes. Recent advances in molecular profiling of gastric stump carcinoma have identified distinct molecular subtypes, thereby providing novel therapeutic targets. Also, reports of gastric stump carcinoma following pancreatoduodenectomy and bariatric surgery highlight the need for more research to standardize the diagnosis, staging, and treatment of these tumors. The present review aims to provide an overview of gastric stump carcinoma highlighting the differences in clinicopathological profile and management compared to primary gastric carcinoma.

Prognostic value of lymph node density on cancer staging system for gastric cancer without distal metastasis: a population-based analysis of SEER database

Background

Accurate tumor staging is the cornerstone of tumor treatment. Current tumor staging system for gastric cancer (GC) is based on regional positive lymph nodes while ignoring the total number of examined lymph nodes. We aim to assess the prognostic value of lymph node density (LND), the ratio of positive nodes to the total number examined nodes, in GC without distal metastasis.

Methods

Clinical information of patients with histologically confirmed GC and without distal metastasis was identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. The X-Tile software was used to identify the ideal prognosis-related cutoff point for LND. The prognostic value of LND on cancer-specific survival (CSS) and overall survival (OS) was assessed in Cox regression models. Subgroup analysis stratified by LND was performed on current lymph node staging system to further explore the interaction between LND and current lymph node staging system.

Results

A total of 4281 participants were identified from the SEER database for the final analysis. The optimal prognosis-related cutoff values of LND were calculated as 0.1 and 0.4, and LND was divided into three levels: LND1 (< 0.1), LND2 (> = 0.1, < 0.4), and LND3 (> = 0.4). LND3 was associated with worse CSS and OS in GC patients. Compared to patients with LND1, those with LND2 and LND3 had 2.43 (HR = 2.43, 95% CI 2.09–2.84, P < 0.001) and 4.69 (HR = 4.69, 95% CI 4.02–5.48, P < 0.001) folds increase in mortality in CSS, respectively. Similar results were found in the evaluation of OS in GC patients. Subgroup analysis stratified by LND also found that patients in the same current lymph node stage still had different prognosis due to the different LND levels after adjustment for other prognosis-related covariates (all P values < 0.001).

Conclusion

LND is an independent prognostic factor for GC without distal metastasis. In the current lymph node staging system, LND has potential value in further accurately classifying GC patients without distal metastasis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02795-9.

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.

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.

Positive lymph node ratio is an index in predicting prognosis for remnant gastric cancer with insufficient retrieved lymph node in R0 resection

The staging system of remnant gastric cancer (RGC) has not yet been established, with the current staging being based on the guidelines for primary gastric cancer. Often, surgeries for RGC fail to achieve the > 15 lymph nodes needed for TNM staging. Compared with the pN staging system, lymph node ratio (NR) may be more accurate for RGC staging and prognosis prediction. We retrospectively analyzed the data of 208 patients who underwent R0 gastrectomy with curative intent and who have ≤ 15 retrieved lymph nodes (RLNs) for RGC between 2000 and 2014. The patients were divided into four groups on the basis of the NR cutoffs: rN0: 0; rN1: > 0 and ≤ 1/6; rN2: > 1/6 and ≤ 1/2; and rN3: > 1/2. The 5-year overall survival (OS) rates for rN0, rN1, rN2, and rN3 were 84.3%, 64.7%, 31.5%, and 12.7%, respectively. Multivariable analyses revealed that tumor size (p = 0.005), lymphovascular invasion (p = 0.023), and NR (p < 0.001), but not pN stage (p = 0.682), were independent factors for OS. When the RLN count is ≤ 15, the NR is superior to pN as an important and independent prognostic index of RGC, thus predicting the prognosis of RGC patients more accurately.

Evaluation of Lymph Node Staging Systems as Independent Prognosticators in Remnant Gastric Cancer Patients with an Insufficient Number of Harvested Lymph Nodes

BACKGROUND

The lymph node (LN) ratio (LNR) and the log odds of positive LNs (LODDS) have been proposed as sensitive prognosticators in patients with primary gastric cancer, especially in patients with an insufficient number of harvested LNs. We investigated the association of LNR and LODDS with survival in patients with remnant gastric cancer (RGC) and explored whether these staging methods are prognostic factors in patients with an insufficient number of harvested LNs.

METHODS

The present study retrospectively examined 95 patients with RGC who received gastrectomy between January 2000 and December 2018. The patients were classified according to the adjusted X-tile cutoff for LNR and LODDS. The association between survival rates and clinicopathological features was investigated. The predictive accuracy of the LNR and LODDS was compared with that of the Union for International Cancer Control pathological N factor.

RESULTS

Multivariate analysis revealed that the LNR and LODDS were independent risk factors for recurrence-free survival (RFS) [hazard ratio (HR) 2.623, p = 0.020; HR 3.404, p = 0.004, respectively] and overall survival (OS) (HR 3.694, p = 0.003; HR 2.895, p = 0.022, respectively) in patients with RGC. Moreover, even in patients with 15 or fewer harvested LNs, only the LNR was a significant independent risk factor for RFS (HR 21.890, p < 0.001) and OS (HR 6.597, p = 0.002). The receiver operating characteristic curves revealed that the prognostic accuracy of the three methods was comparable (p > 0.05).

CONCLUSION

LNR has significant prognostic value for patients with RGC, including those with an insufficient number of harvested LNs.

Comparisons of remnant primary, residual, and recurrent gastric cancer and applicability of the 8th AJCC TNM classification for remnant gastric cancer staging

BACKGROUND

Because there is no well-established postoperative staging system for patients with remnant gastric cancer (RGC), we compared the overall survival of patients categorized with the 8th AJCC TNM staging system.

METHOD

A total of 391 patients underwent surgery for RGC at our institution between 1996 and 2019. Among them, 201 patients received their first surgery at our institution and 190 received primary surgery elsewhere. We retrospectively reviewed their medical records and classified each according to Kaminishi's classification and the 8th AJCC TNM staging system for comparison and analysis.

RESULTS

All 201 patients who underwent their first operation at our institution for malignancy were classified as primary (n = 41, 20.4%), residual (n = 103, 51.2%), and recurrent (n = 57, 28.4%) RGC. The 5-year overall survival (OS) rates for the primary, residual, and recurrent RGC groups were 78.1%, 73.8% and 56.0%, respectively (p = 0.004). In a multivariate analysis, RGC classification was an independent prognostic factor along with the TNM staging system (p = 0.001). However, there was no significant difference in OS between the three groups of the same TNM stage. In addition, the OS of each stage related to primary cancer was not significantly different from the OS of RGC patients classified in TNM staging.

CONCLUSION

The RGC classification system we used may reflect the comprehensive aspects of previous disease states and predict the prognosis of patients with gastric cancer. In addition, the 8th AJCC TNM classification is a practical and applicable staging system for RGC.

Tumor deposit serves as a prognostic marker in gastric cancer: A propensity score-matched analysis comparing survival outcomes

BACKGROUND

Gastric cancer (GC) treatment is determined by accurate tumor staging. The value of tumor deposit (TD) in prognostic prediction staging system is not yet determined.

METHODS

We retrospectively analyzed clinical information on GC patients who underwent gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital from July 2014 to June 2016. Propensity score matching (PSM) was performed to reduce the possibility of selection bias according to the presence of TD.

RESULTS

Of the 1034 GC patients, 240 (23.21%) presented with TD, which was associated with younger age and larger tumor size (all P < .05). TD-positive patients had a worse survival than TD-negative patients before (P < .001) and after (P = .017) matching. Multivariable analysis showed that mortality risk of patients with TD increased by 58%, 62%, 37%, and 40% in the crude (HR = 1.58, 95% CI 1.32-1.89, P < .001), adjusted I (HR = 1.62, 95% CI 1.35-1.94, P < .001), adjusted II (HR = 1.37, 95% CI 1.13-1.66, P = .001), and adjusted III (HR = 1.40, 95% CI 1.16-1.68, P < .001) models before matching. Similarly, in the PSM cohort patients with TD had worse prognosis in the crude (HR = 1.32, 95% CI 1.07-1.63, P = .011), adjusted I (HR = 1.35, 95% CI 1.09-1.67, P = .005), adjusted II (HR = 1.26, 95% CI 1.00-1.58, P = .049), and adjusted III (HR = 1.33, 95% CI 1.07-1.65, P = .010) models. TD had a similar value range between N1 and N2 stages among different models.

CONCLUSIONS

Among GC patients, TD is associated with survival and may have a role in the staging of patients.

Conditional survival and recurrence of remnant gastric cancer after surgical resection: A multi-institutional study

The present study was designed to evaluate the dynamic survival and recurrence of remnant gastric cancer (RGC) after radical resection and to provide a reference for the development of personalized follow-up strategies. A total of 298 patients were analyzed for their 3-year conditional overall survival (COS3), 3-year conditional disease-specific survival (CDSS3), corresponding recurrence and pattern changes, and associated risk factors. The 5-year overall survival (OS) and the 5-year disease-specific survival (DSS) of the entire cohort were 41.2% and 45.8%, respectively. The COS3 and CDDS3 of RGC patients who survived for 5 years were 84.0% and 89.8%, respectively. The conditional survival in patients with unfavorable prognostic characteristics showed greater growth over time than in those with favorable prognostic characteristics (eg, COS3, ≥T3: 46.4%-83.0%, Δ36.6% vs ≤T2: 82.4%-85.7%, Δ3.3%; P < 0.001). Most recurrences (93.5%) occurred in the first 3 years after surgery. The American Joint Committee on Cancer (AJCC) stage was the only factor that affected recurrence. Time-dependent Cox regression showed that for both OS and DSS, after 4 years of survival, the common prognostic factors that were initially judged lost their ability to predict survival (P > 0.05). Time-dependent logistic regression analysis showed that the AJCC stage independently affected recurrence within 2 years after surgery (P < 0.05). A postoperative follow-up model was developed for RGC patients. In conclusion, patients with RGC usually have a high likelihood of death or recurrence within 3 years after radical surgery. We developed a postoperative follow-up model for RGC patients of different stages, which may affect the design of future clinical trials.

Clinicopathological Evaluation of Gastric Signet Ring Cell Carcinoma: Our Experience

Aim

Gastric cancer is one of the most common cancers worldwide. In Turkey, stomach cancer is ranked 5th among men and 8th among women in all cancers and is located in the forefront in cancer-related deaths. Signet ring cell adenocarcinoma, which is the histopathological subtype of gastric cancer, has a poor prognosis. The incidence of signet ring cell adenocarcinoma is rising. In the present study, we aimed to describe the clinicopathologic features of signet ring cell adenocarcinoma.

Materials and Methods

A total of 79 patients with 30 being female (38%) and 49 male (62%) who were diagnosed with gastric signet ring cell adenocarcinoma in the Medical Oncology Department of Ankara Numune Training and Research Hospital between January 2004 and October 2015 were retrospectively evaluated.

Results

The baseline demographic characteristics of the patients, such as tumor localization, tumor stage, preoperative serum tumor markers, and treatment type (surgery and chemotherapy regimen), and the effects of these variables on survival and mortality were evaluated. Total surgery, stage III disease, moderate to poor grade, preoperative serum CA 19-9 and CEA levels were found as independent predictors of progression risk (p < 0.05). Each 1 ng/mL increase in preoperative serum CEA level was found to increase the risk of progression by 1.20 folds. Again, each 1 U/mL in preoperative serum CA 19-9 level was found to increase the risk of progression and mortality by 1.06 folds.

Conclusion

The clinicopathologic features of signet ring cell stomach cancer were described. Tumor localization and disease, CA 19-9 and CEA levels, and treatment type (surgery and chemotherapy regimen) were effective on survival and mortality. However, further studies with larger patient groups are needed on this issue.

How to cite this article

Altay SB, Akkurt G, Yılmaz N, et al. Clinicopathological Evaluation of Gastric Signet Ring Cell Carcinoma: Our Experience. Euroasian J Hepato-Gastroenterol 2020;10(2):76–84.

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.

Young age increases risk for lymph node positivity in gastric cancer: A Chinese multi-institutional database and US SEER database study

Object: The risk of lymph node positivity (LN+) in gastric cancer (GC) impacts therapeutic recommendations. The aim of this study was to quantify the effect of younger age on LN+.

Methods: Data from a Chinese multi-institutional database and the US SEER database on stage I to III resected GC were analyzed for the relationship between age and LN+ status. The association of age and LN+ status was examined with logistic regression separately for each T stage, adjusting for multiple covariates. Poisson regression was used to evaluate age and number of LN+.

Results: 4,905 and 14,877 patients were identified in the China and SEER datasets respectively. 479 (9.8%) patients were under age 40 years, with 768 (15.7%) between age 40 and 49 years in China dataset, and 416 (2.8%) patients were under age 40 years, with 1176 (7.9%) between age 40 and 49 years in SEER dataset. Both datasets exhibited significantly proportional decreases of N3a and N3b LN+ with age increasing. Patients younger than age 40 years were more likely to show LN+ compared with the reference age 60 to 69 years. The youngest patients had the highest ORs of N1, N2, N3a, and N3b vs N0 LN+ within T4 stage of China dataset and T3 stage of SEER dataset, the values of ORs decreased with increasing age. Young age was a predictor of an increased number of LNs positive for each T stage.

Conclusion: In the two large datasets, young age at diagnosis is associated with an increased risk of LN+.

Clinicopathologic features of remnant gastric cancer after curative distal gastrectomy according to previous reconstruction method: a retrospective cohort study

BACKGROUND

Survival rate of patients treated for gastric cancer has increased due to early detection and improvements of surgical technique and chemotherapy. Increase in survival rate has led to an increase in the risk for remnant gastric cancer (RGC). The purpose of this study was to investigate clinicopathologic features of RGC according to previous reconstruction method and factors affecting the interval from previous curative distal gastrectomy for gastric cancer to RGC occurrence.

METHODS

Medical records of patients diagnosed with RGC at Yeungnam University Medical Center from January 2000 to December 2017 who had a history of distal gastrectomy with D2 LN dissection due to gastric cancer were reviewed retrospectively.

RESULTS

Forty-eight patients were enrolled in this study. The mean interval of 48 RGC patients was 105.6 months (8.8 years). RGC after Billroth II reconstruction recurred more often at anastomosis site than RGC after Billroth I reconstruction (p = 0.001). The mean interval of RGC after Billroth I reconstruction was 67 months, shorter than 119 months of RGC after Billroth II reconstruction (p = 0.003). On the contrary, interval showed no difference according to stage of previous gastric cancer, remnant gastric cancer, or sex (p = 0.810, 0.145, and 0.372, respectively).

CONCLUSIONS

RGC after Billroth I reconstruction tends to arise earlier at non-anastomosis site than RGC after Billroth II. Therefore, we should examine non-anastomosis site carefully from the beginning of surveillance after gastric cancer surgery with Billroth I reconstruction for better outcome.

INTRODUCTION OF THE NEW LYMPHOPARIETAL INDEX FOR GASTRIC CANCER PATIENTS

Background:

The identification of prognostic factors of gastric cancer (GC) has allowed to predict the evolution of patients.

Aim:

Assess the reliability of the lymphoparietal index in the prediction of long-term survival in GC treated with curative intent.

Method:

Prospective study of the Universidad de Chile Clinical Hospital, between May 2004 and May 2012. Included all gastric cancer surgeries with curative intent. Exclusion criteria were: gastrectomies due to benign lesions, stage 4 cancers, R1 resections, palliative procedures, complete esophagogastrectomies and emergency surgeries.

Results:

A total of 284 patients were included; of the sample 65.4% were male,mean age of 64.5 years,75% were advanced cancers, 72.5% required a total gastrectomy, 30 lymph nodes harvest. Surgical morbidity and mortality were 17.2% and 1.7%. 5-year survival was 56.9%. The N+/T index could predict long-term survival in all de subgrups (p<0.0001), although had a reliable prediction in early GC (p=0.005), advanced GC (p<0.0001), signet ring cell GC (p<0.0001), proximal GC (p<0.0001) and distal GC (p<0.0001). The ROC curves N+/T index, LNR and T classification presented areas below the curve of 0.789, 0.786 and 0,790 respectively, without a significant statistical difference (p=0.96).

Conclusion:

The N+/T index is a reliable quotient in the prognostic evaluation of gastric adenocarcinoma patients who have been resected with curative intent.

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.

Pancreatic cancer arising from the remnant pancreas after pancreatectomy: a multicenter retrospective study by the Kyushu Study Group of Clinical Cancer

BACKGROUND

After initial pancreatic resection, local recurrence of pancreatic cancer (PC) or new primary PC can develop in the remnant. There are limited data available regarding this so-called remnant PC. The aim of this retrospective study was to clarify the clinical features and establish a treatment strategy for remnant PC.

METHODS

A multicenter retrospective study with the Kyushu Study Group of Clinical Cancer was carried out. Clinical data from 50 patients who developed remnant PC were analyzed. RAS mutation analysis of the initial tumor and of remnant PC was performed in 17 cases.

RESULTS

The initial pancreatic resections were performed for 37 invasive ductal carcinomas, and for 13 other tumors. Thirty-seven patients underwent a second pancreatectomy for remnant PC (resected group), while thirteen patients were not operated (unresected group). The median overall survival times were 42.2 months in the resected group and 12.3 months in the unresected group (HR 0.374; 95% CI 0.17-0.83). In RAS mutation analysis, 14 cases had at least 1 missense variant of KRAS, HRAS, or NRAS in the initial pancreatic tumor and/or remnant PC. The same missense variants between the initial tumor and remnant PC were discovered only in KRAS of one patient, and in HRAS of one patient. No case had completely consistent missense variants between the initial tumor and remnant PC.

CONCLUSIONS

This study found that repeated pancreatectomy for remnant PC can prolong patient survival, and RAS mutation analysis indicated that many remnant PCs are developed from metachronous multifocal origins.

Development and External Validation of Web-Based Models to Predict the Prognosis of Remnant Gastric Cancer after Surgery: A Multicenter Study

BACKGROUND

Remnant gastric cancer (RGC) is a rare malignant tumor with poor prognosis. There is no universally accepted prognostic model for RGC.

METHODS

We analyzed data for 253 RGC patients who underwent radical gastrectomy from 6 centers. The prognosis prediction performances of the AJCC7th and AJCC8th TNM staging systems and the TRM staging system for RGC patients were evaluated. Web-based prediction models based on independent prognostic factors were developed to predict the survival of the RGC patients. External validation was performed using a cohort of 49 Chinese patients.

RESULTS

The predictive abilities of the AJCC8th and TRM staging systems were no better than those of the AJCC7th staging system (c-index: AJCC7th vs. AJCC8th vs. TRM, 0.743 vs. 0.732 vs. 0.744; P>0.05). Within each staging system, the survival of the two adjacent stages was not well discriminated (P>0.05). Multivariate analysis showed that age, tumor size, T stage, and N stage were independent prognostic factors. Based on the above variables, we developed 3 web-based prediction models, which were superior to the AJCC7th staging system in their discriminatory ability (c-index), predictive homogeneity (likelihood ratio chi-square), predictive accuracy (AIC, BIC), and model stability (time-dependent ROC curves). External validation showed predictable accuracies of 0.780, 0.822, and 0.700, respectively, in predicting overall survival, disease-specific survival, and disease-free survival.

CONCLUSIONS

The AJCC TNM staging system and the TRM staging system did not enable good distinction among the RGC patients. We have developed and validated visual web-based prediction models that are superior to these staging systems.

Pancreatic Cancer Arising From the Remnant Pancreas: Is It a Local Recurrence or New Primary Lesion?

Local recurrence of pancreatic cancer (PC) can occur in the pancreatic remnant. In addition, new primary PC can develop in the remnant. There are limited data available regarding this so-called remnant PC. The aim of this review was to describe the characteristics and therapeutic strategy regarding remnant PC. A literature search was performed using Medline published in English according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The incidence of remnant PC has been reported to be 3% to 5%. It is difficult to distinguish local recurrence from new primary PC. Genetic diagnosis such as Kirsten rat sarcoma viral oncogene homolog mutation may resolve this problem. For patients with remnant PC, repeated pancreatectomy can be performed. Residual total pancreatectomy is the most common procedure. Recent studies have described the safety of the operation because of recent surgical progress and perioperative care. The patients with remnant PC without distant metastasis have shown good long-term outcomes, especially those who underwent repeated pancreatectomy. Adjuvant chemotherapy may contribute to longer survival. In conclusion, this review found that both local recurrence and new primary PC can develop in the pancreatic remnant. Repeated pancreatectomy for the remnant PC is a feasible procedure and can prolong patient survival.

Lymphadenectomy with Optimum of 29 Lymph Nodes Retrieved Associated with Improved Survival in Advanced Gastric Cancer: A 25,000-Patient International Database Study

BACKGROUND

Gastric adenocarcinoma is an aggressive disease with frequent lymph node (LN) metastases for which lymphadenectomy results in a survival benefit. In the US, the National Comprehensive Cancer Network guidelines recommend D2 lymphadenectomy or a minimum of 15 LNs retrieved. However, retrieval of only 15 LNs is considered by most international guidelines as inadequate. We sought to evaluate the survival benefits associated with a more complete lymphadenectomy.

STUDY DESIGN

An international database was constructed by combining gastric cancer cases from the Surveillance, Epidemiology, and End Results program database (n = 13,932) and the Yonsei University Gastric Cancer database (n = 11,358) (total n = 25,289). Kaplan-Meier survival analysis was performed along with Joinpoint analysis to obtain the optimal number of LNs to retrieve based on survival. Prognostic significance of number of nodes retrieved was then confirmed with univariate and multivariate analyses.

RESULTS

Analysis for both mean and median survival yielded 29 LNs removed as the Joinpoint. This was confirmed with multivariate analysis, where 15 retrieved LNs cutoff fell out of the model and 29 retrieved LNs remained intact, with a hazard ratio of 0.799 (95% CI 0.759 to 0.842; p < 0.001). Stage-stratified Kaplan-Meier analysis for a cutoff point of 29 LNs also demonstrated a statistically significant improvement in survival.

CONCLUSIONS

Joinpoint analysis has allowed for the creation of a model demonstrating the point at which additional dissection would not provide additional benefit. This large international dataset analysis demonstrates that the maximal survival advantage is seen by performing a lymphadenectomy with a minimum of 29 LNs retrieved.