Evaluation of the American Joint Committee on Cancer 8th edition staging system for gastric cancer patients after preoperative therapy

An integrated radiopathomics machine learning model to predict pathological response to preoperative chemotherapy in gastric cancer

RATIONALE AND OBJECTIVES

Accurately predicting the pathological response to chemotherapy before treatment is important for selecting the appropriate treatment groups, formulating individualized treatment plans, and improving the survival rates of patients with gastric cancer (GC).

METHODS

We retrospectively enrolled 151 patients diagnosed with GC who underwent preoperative chemotherapy and surgical resection at the Affiliated Hospital of Qingdao University between January 2015 and June 2023. Both pretreatment-enhanced computer technology images and whole slide images of pathological hematoxylin and eosin-stained sections were available for each patient. The image features were extracted and used to construct an ensemble radiopathomics machine learning model. In addition, a nomogram was developed by combining the imaging features and clinical characteristics.

RESULTS

In total, 962 radiomics and 999 pathomics signatures were extracted from 106 patients in the training cohort. A fusion radiopathomics model was constructed using 13 radiomics and 5 pathomics signatures. The fusion model showed favorable performance compared to single-omics models, with an area under the curve (AUC) of 0.789 in the validation cohort. Moreover, a combined radiopathomics nomogram (RPN) was developed based on radiopathomics features and the Borrmann type, which is a classification method for advanced GC according to tumor growth pattern and gross morphology. The RPN showed superior predictive performance in the training (AUC 0.880) and validation cohorts (AUC 0.797). The decision curve analysis showed that RPN could provide favorable clinical benefits to patients with GC.

CONCLUSIONS

RPN was able to predict the pathological response to preoperative chemotherapy with high accuracy, and therefore provides a novel tool for personalized treatment of GC.

Interleukin-6 as a Predictive Factor of Pathological Response to FLOT Regimen Systemic Treatment in Locally Advanced Gastroesophageal Junction or Gastric Cancer Patients

BACKGROUND

Perioperative treatment is a gold standard in locally advanced gastric cancer or GEJ cancer in the Western population. Unfortunately, the response rate after neoadjuvant chemotherapy (NAC) remains limited. Moreover, there are currently no biomarkers enabling an individual prediction of therapeutic efficacy. The aim of this study was the identification of serum biomarkers of early response to NAC.

METHODS

We conducted this prospective study in the MSCNRIO in Warsaw, Poland. A total of 71 patients and 15 healthy volunteers gave informed consent. Complete blood count, carcinoembryonic antigen (CEA), carcinoma antigen 125 (CA125), carcinoma antigen 19.9 (CA19.9), and fibrinogen (F) were measured at baseline and before every cycle. Circulating tumour cells (CTCs) and interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) were measured in a pilot group of 40 patients at baseline and before cycle two (C2) and cycle three (C3).

RESULTS

Of all the measured parameters, only the IL-6 serum level was statistically significant. The IL-6 level before C2 of chemotherapy was significantly decreased in the complete pathological response (pCR) vs. the non-pCR group (3.71 pg/mL vs. 7.63 pg/mL, p = 0.004). In all patients with an IL-6 level below 5.0 pg/mL in C2, tumour regression TRG1a/1b according to the Becker classification and ypN0 were detected in postoperative histopathological specimens. The IL-6 level before C1 of chemotherapy was significantly elevated in ypN+ vs. ypN0 (7.69 pg/mL vs. 2.89 pg/mL, p = 0.022).

CONCLUSIONS

The trial showed that an elevated level of IL-6 prior to treatment and C2 might be a predictor of pathological response to NAC.

Independent Stage Classification for Gastroesophageal Junction Adenocarcinoma

In gastroesophageal junction (GEJ) adenocarcinoma cases, a prognosis based on ypTNM staging could be affected by preoperative therapy. Patients with esophageal adenocarcinoma and gastric adenocarcinoma who underwent preoperative therapy followed by surgical resection from 2006 through 2017 were identified in the National Cancer Database. To enable stage-by-stage OS comparisons, tumors were classified into four gross ypTNM groups: ypT1/2, N-negative; ypT1/2, N-positive; ypT3/4, N-negative; and ypT3/4, N-positive. Prognostic factors were examined, and an OS prediction nomogram was developed for patients with abdominal/lower esophageal and gastric cardia adenocarcinoma, representing GEJ cancers. We examined 25,463 patient records. When compared by gross ypTNM group, the abdominal/lower esophageal and gastric cardia adenocarcinoma groups had similar OS rates, differing from those of other esophageal or gastric cancers. Cox regression analysis of patients with GEJ cancers showed that preoperative chemoradiotherapy was associated with shorter OS than preoperative chemotherapy after adjustment for the ypTNM group (hazard ratio 1.31, 95% CI 1.24-1.39, p < 0.001), likely owing to downstaging effects. The nomogram had a concordance index of 0.833 and a time-dependent area under the curve of 0.669. OS prediction in GEJ adenocarcinoma cases should include preoperative therapy regimens. Our OS prediction nomogram provided reasonable OS prediction for patients with GEJ adenocarcinoma, and future validation is needed.

Borrmann Type Predicts Response to Preoperative Therapy in Advanced Gastric Cancer

PURPOSE

The Borrmann classification system is widely used to classify advanced gastric cancer (GC). No studies have focused on the relationship between Borrmann type and response to preoperative therapy.

METHODS

Patients with advanced GC who received preoperative therapy followed by curative-intent gastrectomy from September 2016 through September 2021 were identified. Clinicopathologic characteristics were compared by Borrmann type. Logistic regression models were fit to analyze the relationship between Borrmann type and pCR rate.

RESULTS

Of the 227 patients who underwent gastrectomy during the period studied, 73 had pretreatment endoscopic images available for analysis. We classified the tumors as follows: Borrmann type 1, 4 (6%); type 2, 17 (23%); type 3, 33 (45%); and type 4, 19 (26%). Nine patients (12%) achieved pCR; 6 of these (67%) had type 1/2 GC and 3 (33%) had type 3. Multivariable logistic regression showed that Borrmann type 3/4 was the only independent factor associated with pCR (odds ratio 0.12; p = 0.023), but 2-year overall survival rates did not differ by Borrmann type (p = 0.216).

CONCLUSION

Patients with Borrmann type 3/4 advanced GC have a lower likelihood of achieving pCR after preoperative therapy than those with type 1/2 GC. Determining the Borrmann type preoperatively can guide treatment decision-making.

Is Pathologic Complete Response a Good Predictor for the Long-Term, Clinical Outcome in Patients with Gastric Cancer After Neoadjuvant Chemotherapy? A Retrospective, Multi-institution Study in China

BACKGROUND

Many studies have used pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) as the primary endpoint for the short-term efficacy in gastric cancer, but whether it is a good indicator for overall survival is poorly understood.

METHODS

This study reviewed a multi-institution database of patients who underwent radical gastrectomy and achieved pCR after NAC. Cox regression models were used to identify clinicopathologic predictors of overall survival (OS) and disease-free survival (DFS). Survival curves were calculated by using the Kaplan-Meier method and compared by means of the log-rank test.

RESULTS

OS and DFS in patients with pCR were significantly higher than in those with non-pCR (both P < 0.001). Multivariable analysis confirmed pCR was an independent prognostic factor for OS and DFS (P = 0.009 and P = 0.002 for OS and DFS, respectively). However, the survival benefit for pCR was present only for ypN0 tumors (P = 0.004 and P = 0.001 for OS and DFS, respectively), and OS (P = 0.292) and DFS (P = 0.285) among patients with ypN+ gastric cancer could not be stratified by pCR.

CONCLUSIONS

In our study, pCR is an independent prognostic factor for OS and DFS, but the survival benefit for pCR is present only for ypN0 tumors but not ypN+ tumors.

Efficacy of chemotherapy combined with surgical resection for gastric cancer with synchronous ovarian metastasis: A propensity score matching analysis

BACKGROUND

Ovarian metastasis from gastric cancer (GC) is characterized by aggressive biological behavior and poor outcome. Currently, there is no standard treatment mode for such patients. Thus, we evaluated the efficacy of conversion therapy in patients with synchronous ovarian metastasis from GC in this study.

METHODS

About 219 GC patients with ovarian metastasis in 2011-2020 were enrolled. Two groups were established based on the different treatment: the conversion therapy group (chemotherapy combined with surgical resection, CS group) and the non-conversion therapy group (NCS group). Propensity score matching (PSM) was used to analyze the efficacy of different treatment modes on the prognosis of these patients.

RESULTS

Ninety-two patients were included according to PSM results, with 46 patients each in CS and NCS groups. The median overall survival (OS) in the CS group was notably better than that in the NCS group (p < 0.001). Twenty-six patients (56.52%) in the CS group achieved R0 resection, and they had a better prognosis (p = 0.003). Compared with patients who underwent simultaneous gastrectomy and ovarian metastasectomy (CSb group), those who underwent ovarian metastasectomy before systemic chemotherapy (CSa group) had a higher R0 resection rate (p = 0.016) and longer survival time (p = 0.002). A total of 38 patients (41.30%) across both groups received hyperthermic intraperitoneal chemotherapy (HIPEC), and these patients had a better survival (p = 0.043).

CONCLUSION

The conversion therapy is safe and effective for patients with synchronous ovarian metastasis from GC and can improve their prognosis. However, our results need to be confirmed by more randomized controlled clinical studies.

ENDOSCOPIC CHARACTERISTICS OF PATIENTS WITH COMPLETE PATHOLOGICAL RESPONSE AFTER NEOADJUVANT CHEMOTHERAPY FOR GASTRIC AND ESOPHAGOGASTRIC JUNCTION ADENOCARCINOMAS

Background:

Gastric and esophagogastric junction adenocarcinoma are responsible for approximately 13.5% of cancer-related deaths. Given the fact that these tumors are not typically detected until they are already in the advanced stages, neoadjuvancy plays a fundamental role in improving long-term survival. Identification of those with complete pathological response (pCR) after neoadjuvant chemotherapy (NAC) is a major challenge, with effects on organ preservation, extent of resection, and additional surgery. There is little or no information in the literature about which endoscopic signs should be evaluated after NAC, or even when such re-evaluation should occur.

Aim:

To describe the endoscopic aspects of patients with gastric and esophagogastric junction adenocarcinomas who underwent NAC and achieved pCR, and to determine the accuracy of esophagogastroduodenoscopy (EGD) in predicting the pCR.

Methods:

A survey was conducted of the medical records of patients with these tumors who were submitted to gastrectomy after NAC, with anatomopathological result of pCR.

Results:

Twenty-nine patients were identified who achieved pCR after NAC within the study period. Endoscopic responses were used to classify patients into two groups: G1-endoscopic findings consistent with pCR and G2-endoscopic findings not consistent with pCR. Endoscopic evaluation in G1 was present in an equal percentage (47.4%; p=0.28) in Borrmann classification II and III. In this group, the predominance was in the gastric body (57.9%; p=0.14), intestinal subtype with 42.1% (p=0.75), undifferentiated degree, 62.5% (p=0.78), Herb+ in 73.3% (p=0.68). The most significant finding, however, was that the time interval between NAC and EGD was longer for G1 than G2 (24.4 vs. 10.2 days, p=0.008).

Conclusion:

EGD after NAC seems to be a useful tool for predicting pCR, and it may be possible to use it to create a reliable response classification. In addition, the time interval between NAC and EGD appears to significantly influence the predictive power of endoscopy for pCR.

Association of IGF-1 and IGFBP-3 levels with gastric cancer: A systematic review and meta-analysis

PURPOSE

Many studies have investigated the association between serum IGF-1 and IGFBP levels with gastric cancer (GC), but the results remained inconclusive. In this work, we performed a systematic review and meta-analysis to examine the precise association of serum levels of IGF-1 and IGFBP with GC.

METHODS

A comprehensive systematic search was carried out in PubMed/MEDLINE, SCOPUS, Web of Science, and EMBASE databases for (nested) case-control studies that reported the levels of IGF-1 and IGFBP in GC cases and healthy controls, from inception until October 2020. Weighted mean difference (WMD) was calculated for estimating combined effect size. Subgroup analysis was performed to identify the source of heterogeneity among studies.

RESULTS

We found eight and five eligible studies (with 1541 participants) which provided data for IGF-1 and IGFBP, respectively. All studies on IGFBP reported the IGFBP-3 isoform. The pooled results indicate that GC patients had significantly lower serum IGF-1 [WMD = -26.21 ng/mL (95% CI, -45.58 to -6.85; P = .008)] and IGFBP-3 [WMD = -0.41 ng/mL (95% CI, -0.80 to -0.01; P = .04; I²  = 89.9%; P < .001)] levels than those in healthy subjects. Significant heterogeneity was observed in the association, which could be attributed to the sample size of the studies.

CONCLUSIONS

In conclusion, our study reveals a significantly lower level of IGF-1 and IGFBP-3 in GC patients compared with healthy control subjects.

Chemotherapy Versus Chemotherapy Plus Chemoradiation as Neoadjuvant Therapy for Resectable Gastric Adenocarcinoma: A Multi-institutional Analysis

OBJECTIVE

We compare neoadjuvant chemotherapy (CT) to neoadjuvant chemotherapy plus chemoradiation (CRT) for patients with gastric adenocarcinoma (GA).

SUMMARY OF BACKGROUND DATA

The optimal neoadjuvant therapy regimen for resectable GA is not defined.

METHODS

Utilizing data from 2 high-volume cancer centers, we analyzed patients who underwent surgery for localized GA from 1/1/2000-12/31/2017. Standard CT regimens were used according to treatment period. We compared propensity matched cohorts based on age, sex, race, histology, and clinical stage.

RESULTS

Four-hundred five patients (age 62 ± 12 year, 58% male, 56% White) were analyzed. 231 (57%) received CRT and 174 (43%) received CT. Groups differed based on histopathologic characteristics including preoperative stage (p = 0.013). To control for these differences, propensity matched cohorts of 113 CT and 113 CRT patients were compared. CRT had similar frequencies of microscopically negative resections to CT (93% vs 91%, p = 0.81), but higher rates of complete pathologic response (15% vs 4%, p = 0.003) and lower pathologic stage (p = 0.002). Completion of intended perioperative therapy occurred in 63% of CT and 91% of CRT patients (p < 0.001). Median DFS was 45mo (95%CI: 20-70) in the CT group and 113mo (95%CI: 75-151) in the CRT group (p = 0.018). Median OS was 53mo (95%CI: 30-77) versus 120mo (95%CI: 101-138); p = 0.015.

CONCLUSIONS

In this multi-institutional comparison of neoadjuvant CT and CRT for resectable GA, CRT is associated with higher rates of completed perioperative therapy, higher rates of complete pathologic response, lower pathologic stage, and improved survival.Level of Evidence: Level III.

CT-detected extramural venous invasion-related gene signature for the overall survival prediction in patients with gastric cancer

Background

Computed tomography (CT)‐detected extramural venous invasion (EMVI) has been identified as an independent factor that can be used for risk stratification and prediction of prognosis in patients with gastric cancer (GC). Overall survival (OS) is identified as the most important prognostic indicator for GC patients. However, the molecular mechanism of EMVI development and its potential relationship with OS in GC are not fully understood. In this radiogenomics‐based study, we sought to investigate the molecular mechanism underlying CT‐detected EMVI in patients with GC, and aimed to construct a genomic signature based on EMVI‐related genes with the goal of using this signature to predict the OS.

Materials and Methods

Whole mRNA genome sequencing of frozen tumor samples from 13 locally advanced GC patients was performed to identify EMVI‐related genes. EMVI‐prognostic hub genes were selected based on overlapping EMVI‐related differentially expressed genes and OS‐related genes, using a training cohort of 176 GC patients who were included in The Cancer Genome Atlas database. Another 174 GC patients from this database comprised the external validation cohort. A risk stratification model using a seven‐gene signature was constructed through the use of a least absolute shrinkage and selection operator Cox regression model.

Results

Patients with high risk score showed significantly reduced OS (training cohort, p = 1.143e‐04; validation cohort, p = 2.429e‐02). Risk score was an independent predictor of OS in multivariate Cox regression analyses (training cohort, HR = 2.758; 95% CI: 1.825–4.169; validation cohort, HR = 2.173; 95% CI: 1.347–3.505; p < 0.001 for both). Gene functions/pathways of the seven‐gene signature mainly included cell proliferation, cell adhesion, regulation of metal ion transport, and epithelial to mesenchymal transition.

Conclusions

A CT‐detected EMVI‐related gene model could be used to predict the prognosis in GC patients, potentially providing clinicians with additional information regarding appropriate therapeutic strategy and medical decision‐making.

Tumor Regression Grade in Gastric Cancer After Preoperative Therapy

BACKGROUND

The Cancer Staging Manual, 8th edition, now includes post-neoadjuvant therapy (ypTNM) staging for gastric cancer patients. Our purpose was to determine whether the tumor regression grade (TRG) of the primary tumor is useful for predicting the survival of these patients.

METHODS

We performed a retrospective review of an institutional database and identified patients with clinically non-metastatic gastric adenocarcinoma who underwent preoperative chemotherapy or chemoradiation therapy before gastrectomy. Pathology reports were reviewed, and TRG was classified as follows: 0 (complete response), 1 (viable tumor cells ≤ 1-2%), 2 (viable cells ≤ 50%), or 3 (viable cells > 50%).

RESULTS

Of the 356 patients identified, including 80 (23%) with a gastroesophageal junction tumor, 268 (75%) had undergone preoperative chemoradiation therapy. Fifty-six (16%) had TRG 0, 57 (16%) TRG 1, 128 (36%) TRG 2, and 115 (32%) TRG 3. No association between TRG and pretreatment factors was identified, except for signet-ring cell histologic type and tumor location. A higher TRG was associated with more advanced ypT and ypN categories (both p < 0.001), ypM1 (p = 0.004), and R1 resection (p = 0.052). The median overall survival (OS) duration was 6.6 years, and the 5-year OS rate was 54.1%. TRG 3 was associated with a shorter OS duration than were other TRG scores (p = 0.015), while the OS did not differ significantly among the TRG 0-2 groups (p = 0.803). On multivariable analysis, TRG was not associated with OS after adjustment for ypN status.

CONCLUSION

In gastric cancer patients who underwent preoperative therapy, TRG 3 was associated with advanced ypStage and R1 resection. Patients with TRG 3 had a shorter OS duration because of associated advanced ypStage, particularly ypN+ status.

Benchmarks for nodal yield and ratio for node-positive gastric cancer

BACKGROUND

We aimed to elucidate prognostic markers of node-positive gastric cancers with a focus on examined lymph nodes and lymph node ratio.

METHODS

Patients treated with curative-intent gastrectomy at The University of Texas MD Anderson Cancer Center from 1995-2019 were evaluated. Patients with non-metastatic, node-positive gastric cancers were considered for analysis.

RESULTS

Of 775 patients, 281 met the inclusion criteria. The mean age was 58 years, 61% were male, 51% were White, 65% received preoperative therapy, and 71% of tumors were located in the gastric body. The median overall survival was 3.6 years, and 1-, 5-, and 10-year overall survival rates were 91%, 41%, and 29%, respectively. pN3 category was associated with worse overall survival (hazard ratio 1.79, P = .001) and recurrence-free survival (hazard ratio 1.92, P = .004). Nodal burden was associated with aggressive biologic traits in primary tumors, including higher rates of lymphovascular and perineural invasion and lower preoperative therapy response rates. By receiver-operative characteristic analysis, threshold values of ≥30 examined lymph nodes and <30% lymph node ratio were most discriminant for overall survival. On adjusted analysis, positive margins, additional organ resection, <30 examined lymph nodes, and ≥30% lymph node ratio were associated with worse recurrence-free survival and overall survival. Among patients with high node burden (pN3), <30 examined lymph nodes remained significant on adjusted survival analysis.

CONCLUSION

Greater than or equal to 30 examined lymph nodes and <30% lymph node ratio were significantly associated with longer recurrence-free survival and overall survival, independent of lymphadenectomy type. These prognostic benchmarks should be considered in the surgical management of gastric cancer in the United States.

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment-Oncological and Surgical Perspective

Simple Summary

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Therefore, further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Abstract

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. A favourable prognostic impact for ypN0 patients is observed, either due to truly negative LN before the start of therapy or because preoperative therapy achieved a pathologically complete nodal response. Ongoing trials investigating the extent of lymphadenectomy after neoadjuvant therapy will standardise the LN dissection from the multimodal therapy perspective. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Determinants of Survival for Patients with Neoadjuvant-Treated Node-Negative Gastric Cancer

BACKGROUND

This study sought to determine prognostic markers for disease recurrence and survival in a cohort of neoadjuvant-treated, node-negative gastric cancer patients (ypT0-4N0M0).

METHODS

Clinicopathologic data from patients treated with neoadjuvant therapy followed by curative-intent gastrectomy at the University of Texas MD Anderson Cancer Center from 1995 to 2017 were evaluated. Patients with AJCC TNM stage ypT0-4N0M0 were considered for analysis.

RESULTS

The inclusion criteria were met by 212 patients with a mean age of 58.3 years. Of these patients, 60 % were male, 53 % were Caucasian, 87 % received chemoradiation, and 13 % received chemotherapy. The findings showed a median overall survival (OS) rate of 11.3 years, a 5-year survival rate of 72 %, and a 10-year survival rate of 57 %. During a median follow-up period of 5.5 years, 38.2 % of the patients died. In the multivariable analysis, ypT4-stage and nodal yield fewer than 16 were significantly associated with reduced OS. Cancer classified as ypT4 had more aggressive biologic traits, including lymphovascular and perineural invasion, and was treated more aggressively with total gastrectomy and additional organ resection despite frequent positive margins. Depth of invasion remained significantly associated with worse outcome after the analysis controlled for nodal yield and possible stage migration. Compared with ypT0-3 tumors, ypT4 cancers were associated with significantly more recurrences (13 % vs. 45 %; p < 0.05), and the primary modes of failure for ypT4 lesions were local recurrence and peritoneal metastases (88 % of recurrences).

CONCLUSIONS

Depth of primary tumor invasion and nodal yield were significantly associated with OS among the patients with ypT0-4N0M0 gastric cancer. Serosal invasion (ypT4) was associated with a high rate of peritoneal recurrence, and trials of intraperitoneal therapy targeting these patients should be considered.

sMicroRNA-28-5p acts as a metastasis suppressor in gastric cancer by targeting Nrf2

The transcription factor nuclear factor (erythroid-2)-related factor 2 (Nrf2) can principally serve a mode of protection for both the normal cells and cancer cells from cellular stress, and elevates cancer cell survival. microRNA-28 (miR-28) has been involved in the regulation of Nrf2 expression in breast epithelial cells. However, no comprehensive analysis has been conducted regarding the function of miR-28-5p regulating Nrf2 in gastric cancer (GC). In this study, we aimed to evaluate their interaction and biological roles in the migration and invasion of GC cells. The expression of Nrf2 in the cancer tissues harvested from 42 patients with GC was examined by an array of molecular techniques comprising of Immunohistochemical staining, RT-qPCR and Western blot analysis. Kaplan-Meier method was adopted for analysis of the correlation of Nrf2 with the prognosis of GC patients. Interaction between miR-28-5p and Nrf2 was determined using the bioinformatics analysis and dual luciferase reporter gene assay. Gain- and loss-of-function studies of miR-28-5p and Nrf2 were conducted to elucidate their effects on GC cell migration, invasion and metastasis, as well as expression pattern of several epithelial-mesenchymal transition (EMT)-related proteins. Results indicated that the expression pattern of Nrf2 was significantly upregulated in GC tissues and indicative of poor prognosis of GC patients. miR-28-5p was verified to target Nrf2 and downregulate its expression. GC cells with overexpression of miR-28-5p or Nrf2 knockdown exhibited a marked reduction in the migrated and invasive abilities, along with the N-cadherin expression yet an increase of E-cadherin expression. Furthermore, miR-28-5p exerted an inhibitory function on the metastatic and tumorigenicity of GC cells. In conclusion, miR-28-5p is a comprehensive tumor suppressor that inhibits GC cell migration and invasion through repressing the Nrf2 expression. Therefore, miR-28-5p may serve as a potential biomarker for the prognosis of GC and a novel therapeutic target in advanced GC.

Providing Reliable Prognosis to Patients with Gastric Cancer in the Era of Neoadjuvant Therapies: Comparison of AJCC Staging Schemata

Purpose

Patients with gastric cancer who receive neoadjuvant therapy are staged before treatment (cStage) and after treatment (ypStage). We aimed to compare the prognostic reliability of cStage and ypStage, alone and in combination.

Materials and Methods

Data for all patients who received neoadjuvant therapy followed by surgery for gastric adenocarcinoma from 2004 to 2015 were extracted from the National Cancer Database. Kaplan-Meier (KM)curves were used to model overall survival based on cStage alone, ypStage alone, cStage stratified by ypStage, and ypStage stratified by cStage. P-values were generated to summarize the differences in KM curves. The discriminatory power of survival prediction was examined using Harrell's C-statistics.

Results

We included 8,977 patients in the analysis. As expected, increasing cStage and ypStage were associated with worse survival. The discriminatory prognostic power provided by cStage was poor (C-statistic 0.548), while that provided by ypStage was moderate (C-statistic 0.634). Within each cStage, the addition of ypStage information significantly altered the prognosis (P<0.0001 within cStages I–IV). However, for each ypStage, the addition of cStage information generally did not alter the prognosis (P=0.2874, 0.027, 0.061, 0.049, and 0.007 within ypStages 0–IV, respectively). The discriminatory prognostic power provided by the combination of cStage and ypStage was similar to that of ypStage alone (C-statistic 0.636 vs. 0.634).

Conclusions

The cStage is unreliable for prognosis, and ypStage is moderately reliable. Combining cStage and ypStage does not improve the discriminatory prognostic power provided by ypStage alone. A ypStage-based prognosis is minimally affected by the initial cStage.

Preoperative Therapy Regimen Influences the Incidence and Implication of Nodal Downstaging in Patients with Gastric Cancer

Purpose

Nodal downstaging after preoperative therapy for gastric cancer has been shown to impart excellent prognosis, but this has not been validated in a national cohort. The role of neoadjuvant chemoradiation (NACR) in nodal downstaging remains unclear when compared with that of neoadjuvant chemotherapy alone (NAC). Furthermore, it is unknown whether the prognostic implications of nodal downstaging differ by preoperative regimen.

Materials and Methods

Using the National Cancer Database, overall survival (OS) duration was compared among natural N0 (cN0/ypN0), downstaged N0 (cN+/ypN0), and node-positive (ypN+) gastric cancer patients treated with NACR or NAC. Factors associated with nodal downstaging were examined in a propensity score-matched cohort of cN+ patients, matched 1:1 by receipt of NACR or NAC.

Results

Of 7,426 patients (natural N0 [n=1,858, 25.4%], downstaged N0 [n=1,813, 24.4%], node-positive [n=3,755, 50.4%]), 58.2% received NACR, and 41.9% received NAC. The median OS durations of downstaged N0 (5.1 years) and natural N0 (5.6 years) patients were similar to one another and longer than that of node-positive patients (2.1 years) (P<0.001). In the matched cohort of cN+ patients, more recent diagnosis (2010–2015 vs. 2004–2009) (odds ratio [OR], 2.57; P<0.001) and NACR (OR, 2.02; P<0.001) were independently associated with nodal downstaging. The 5-year OS rate of downstaged N0 patients was significantly lower after NACR (46.4%) than after NAC (57.7%) (P=0.003).

Conclusions

Downstaged N0 patients have the same prognosis as natural N0 patients. Nodal downstaging occurred more frequently after NACR; however, the survival benefit of nodal downstaging after NACR may be less than that when such is achieved by NAC.

Chemotherapy Versus Chemotherapy Plus Chemoradiation as Preoperative Therapy for Resectable Gastric Adenocarcinoma: A Propensity Score-Matched Analysis of a Large, Single-Institution Experience

BACKGROUND

We compared oncologic outcomes of patients who received neoadjuvant chemotherapy (CT) with those of patients who received neoadjuvant chemotherapy plus chemoradiation (CRT) for resectable gastric adenocarcinoma.

METHODS

We compared oncologic and survival outcomes of patients who received CT or CRT for gastric adenocarcinoma at our institution between July 1995 and July 2018. We analyzed propensity score-matched cohorts based on age, sex, race, tumor histologic characteristics, and clinical stage.

RESULTS

We identified 440 patients (mean age 61 ± 12 years, 62% male, 55% white); 345 (78%) received CRT, and 95 (22%) received CT. The propensity score-matched cohorts included 65 patients who received CT and 65 who received CRT. The CRT group had similar frequencies of R1 resection margins to the CT group (7.7% vs. 6.2%, p = 0.75) but significantly higher frequency of pathologic complete response (27.7% vs. 1.5%, p < 0.001). The CRT group had lower pathologic stages (p = 0.002). Median disease-free survival was 50.9 months (95% confidence interval [CI]: 4.7-97.2) in the CT group and 122.1 months (95% CI: 69.0-175.1) in the CRT group (p = 0.07). Median overall survival was 70.7 months (95% CI: 23.9-117.5) in the CT group and 122.1 months (95% CI: 68.7-175.4) in the CRT group (p = 0.21).

CONCLUSIONS

Compared with CT, CRT for resectable gastric adenocarcinoma is associated with higher rates of pathologic complete response and subsequent lower final pathologic stage, but survival differences are not significant. Ongoing investigation is necessary to better determine the optimal neoadjuvant therapy and identify patients who receive optimal benefit from CRT.

LEVEL OF EVIDENCE

III.

Impact of tumor regression grade on recurrence after preoperative chemoradiation and gastrectomy for gastric cancer

BACKGROUND AND OBJECTIVES

It is unknown whether the degree of response to preoperative therapy correlates with locoregional recurrence (LR) or distant recurrence (DR) after resection of gastric cancer.

METHODS

Patients who underwent resection of gastric adenocarcinoma following chemotherapy and chemoradiation (1995-2015) were reviewed. The tumor regression grade (TRG) was defined by the percentage of viable tumor cells in the specimen (TRG0 = 0%; TRG1 = 1%-2%; TRG2 = 3%-50%; TRG3 ≥ 50%). The relationships among TRG, recurrence-free survival (RFS), LR, and DR were examined.

RESULTS

Two hundred forty-seven patients met the inclusion criteria (TRG0, 52 [21%]; TRG1, 49 [20%]; TRG2, 98 [40%]; TRG3, 48 [19%]). LR and DR occurred in 6.1% and 32.0% of patients, respectively. No patient with TRG0 experienced LR. R1 resection (6%-15%) and LR (6%-8%) rates were similar among TRG1-3 patients. R1 resection was associated with LR (hazard ratio [HR], 17.85; P < .001). ypN status (HR, 2.44; P = .004) and linitis plastica (HR, 2.90; P < .001) were associated with DR. TRG was not independently associated with RFS, LR, or DR.

CONCLUSIONS

TRG0 imparted excellent local control. However, TRG1-3 patients had similar R1 resection rates and therefore similar LR. DR is associated with ypN status and linitis plastica, not TRG.

Linitis Plastica: a Distinct Type of Gastric Cancer

BACKGROUND

The prognosis of patients with linitis plastica (LP) gastric cancer is reported to be poor. The purpose of our retrospective study was to characterize the clinicopathologic features and survival outcomes of patients with LP, using a univocal definition.

METHODS

We defined LP as gastric cancer that involves more than 1/3 of the gastric wall macroscopically. We reviewed a prospectively maintained institutional database of gastric cancer patients and summarized and compared clinicopathologic factors of patients with and without LP who had undergone gastrectomy. Patients were matched 1:1 using propensity score matching, and their overall survival (OS) rates and durations were compared. Multivariable Cox regression analyses were conducted, using gastrectomy as a time-varying covariate.

RESULTS

We identified 740 patients with radiographically non-metastatic gastric cancer, 157 (21.2%) of whom had LP. Most patients with LP had advanced-stage disease (75.8% had stage IV disease, mainly due to peritoneal involvement). Patients with LP had significantly shorter OS durations than did those without LP in the entire cohort (median OS, 14.0 vs. 33.5 months; p value < 0.001) and in the surgical cohort (median OS after gastrectomy, 21.8 vs. 91.0 months; p < 0.001), as well as in the propensity-matched surgical cohort. In the LP cohort, chemotherapy (hazard ratio [HR] = 0.594; p = 0.076), chemoradiation therapy (HR = 0.346; p = 0.001), and gastrectomy (HR = 0.425; p = 0.003) were associated with a longer OS.

CONCLUSIONS

LP is a phenotype of gastric cancer that often presents at an advanced stage, with a high rate of peritoneal involvement. The survival durations of patients with LP were poor in our study, even in the surgical cohort. The use of preoperative chemotherapy, chemoradiation therapy, and gastrectomy appeared to be important in carefully selected patients with localized LP.

Surgical decision-making and prioritization for cancer patients at the onset of the COVID-19 pandemic: A multidisciplinary approach

In the midst of the coronavirus disease 2019 (COVID-19) pandemic, governmental agencies, state medical boards, and healthcare organizations have called for restricting “elective” operations to mitigate the risk of transmission of the virus amongst patients and healthcare providers and to preserve essential resources for potential regional surges of COVID patients. While the fear of delaying surgical care for many of our patients is deeply challenging for us as cancer care providers, we must balance our personal commitment to providing timely and appropriate oncologic care to our cancer patients with our societal responsibility to protect our patients (including those on whom we are operating), co-workers, trainees, families, and community, from undue risks of contracting and propagating COVID-19. Herein, we present guidelines for surgical decision-making and case prioritization developed among all adult disease specialties in the MD Anderson Cancer Center Departments of Surgical Oncology and Breast Surgical Oncology in Houston, Texas.

Staging laparoscopy and peritoneal cytology in patients with early stage gastric adenocarcinoma

Background

Staging laparoscopy and peritoneal cytology can detect occult metastatic disease prior to treatment of gastric cancer. The yield of peritoneal staging in patients with early stage disease is lacking. We assess the yield of peritoneal staging in early stage gastric cancer and its impact on survival.

Methods

Data were obtained from a prospective database of patients who underwent staging laparoscopy and peritoneal cytology for gastric cancer at our institution between July 1995 and July 2018. Clinical stage was determined by endoscopic ultrasound, and early stage was defined as cT1-2 and cN0. Rates of positive cytology and carcinomatosis at time of laparoscopy were obtained. Univariate analyses were used to compare groups, and Kaplan-Meier survival analyses were used to assess survival outcomes.

Results

Eight hundred sixty-seven patients underwent staging laparoscopy and peritoneal cytology; 56 were defined as early stage. Age was 61 ± 12 years, 66.4% were male, and 62.3% were white. Of the patients with early stage disease, 17.9% had either gross carcinomatosis (10.7%) and/or positive peritoneal cytology (10.9%). All cases of peritoneal disease were in patients with cT2 disease. There were no differences in age, gender, or race based on peritoneal disease (all p > 0.05). The presence of carcinomatosis or positive cytology significantly affected overall survival (p < 0.001), regardless of clinical T or N stage.

Conclusions

Peritoneal staging identifies metastatic disease in a significant number of patients with early stage disease. Given its poor prognosis and alternate therapy options, independent staging laparoscopy and peritoneal cytology should be considered in patients with early stage gastric adenocarcinoma.

Long non-coding RNA-ZNF281 promotes cancer cell migration and invasion in gastric cancer via downregulation of microRNA-124

It has previously been determined that long non-coding (lnc)RNA-zinc finger protein (ZNF)281 serves an oncogenic role in breast cancer; however, the role of lncRNA-ZNF281 in other cancer types is yet to be elucidated. The present study aimed to analyze the role of ZNF281 in gastric cancer by characterizing its activity in cancerous tissues and normal tissues using RT-qPCR. Overexpression experiments were also performed to investigate the interaction between ZNF281 and miR-124, and Transwell assays were conducted to analyze cell invasion and migration. The present study revealed that lncRNA-ZNF281 was upregulated, and that microRNA (miR)-124 was downregulated, in cancerous tissues compared with that in the paired adjacent healthy tissues of patients with gastric cancer. In addition, the expression levels of lncRNA-ZNF281 and miR-124 exhibited a significant inverse association. Furthermore, in vitro cell experiments determined that lncRNA-ZNF281 overexpression resulted in miR-124 inhibition, yet miR-124 overexpression did not influence lncRNA-ZNF281 expression. lncRNA-ZNF281 expression level was also associated with the clinical stage of the patient. Bioinformatics analysis revealed that lncRNA-ZNF281 may target the base pairs in the hairpin loop of the miR-124 precursor. Subsequent in vitro cell experiments indicated that lncRNA-ZNF281 overexpression resulted in promoting the migration and invasiveness of gastric cancer cells, while miR-124 over-expression led to its inhibition. In addition, miR-124 overexpression partially recovered the effects of lncRNA-ZNF281 overexpression. Therefore, lncRNA-ZNF281 may promote cancer cell migration and invasion in gastric cancer via downregulation of miR-124.

Proposed Modification of the 8th Edition of the AJCC Staging System for Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The aim of this study was to improve the 8th edition (8th) of the American Joint Committee on Cancer (AJCC) staging system for pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND

The new 8th AJCC staging system for PDAC was released in October, 2016, and will be applied in clinical practice in 2018.

METHODS

Two large cohorts were included in this analysis. One consisted of 45,856 PDAC patients in the Surveillance, Epidemiology, and End Results (SEER) database (2004-2014), and the other consisted of 3166 PDAC patients in the Fudan University Shanghai Cancer Center (FUSCC) database (2005-2015).

RESULTS

Using the 8th AJCC staging system, the median overall survival of the patients in the same stage varied widely among the different substages. We proposed a modified staging system based on median OS in which we maintained the T, N, and M definitions, but regrouped the substages. In the SEER cohort, the concordance index was higher for local disease with the modified staging system [0.637; 95% confidence interval (CI) 0.631-0.642] than with the 8th AJCC staging system (0.620, 95% CI 0.615-0.626). Similar findings were also observed in the FUSCC cohort. In addition, we verified the reliability of the modified staging system in an analysis of patients with different examined lymph node counts (≥15 or 1-14).

CONCLUSIONS

The modified 8th AJCC staging system for PDAC proposed in this study provides improvements and may be evaluated for potential adoption in the next edition.

Characteristics and Survival of Gastric Cancer Patients with Pathologic Complete Response to Preoperative Therapy

BACKGROUND

Pathologic complete response of a primary tumor (ypT0) after preoperative therapy is associated with improved overall survival (OS). However, whether other variables are associated with outcome for gastric cancer patients with ypT0 status is unknown.

METHODS

This study reviewed an institutional database of patients who underwent resection of gastric or gastroesophageal adenocarcinoma after preoperative therapy and identified patients with ypT0 status. Cox regression models were used to identify clinicopathologic predictors of OS.

RESULTS

Of 77 patients with ypT0 status identified in this study, 36 (47%) had gastroesophageal junction tumors. At presentation, 62 patients (81%) had clinical T3 disease, and 7 (9%) had clinical T4 disease. The clinical nodal status was positive (cN+) for 45 patients (58%). Preoperative chemoradiation was administered to 75 patients (97%). The median follow-up duration was 3.54 years. The median OS was 10 years, and the 5-year OS rate was 61%. Univariable analysis identified age of 65 years or older at the time of diagnosis, histologic grade, and ypN status as significant predictors of OS. Multivariable analysis confirmed age of 65 years or older [hazard ratio (HR), 4.26; p < 0.001] and persistent nodal disease (ypN+ status; HR, 5.12; p < 0.001) to be independently associated with OS. Clinical stage was not associated with survival. In the subset of ypT0N0 patients, no clinicopathologic feature was predictive of survival.

CONCLUSION

For gastric or gastroesophageal adenocarcinoma patients with ypT0 status after preoperative therapy, ypN+ status substantially reduced survival. Pretreatment clinical stage had no impact on OS for patients with a pathologic complete response.

Blast from the past: Perioperative use of the Maruyama computer program for prediction of lymph node involvement in the surgical treatment of gastric cancer following neoadjuvant chemotherapy

BACKGROUND

Surgical quality assurance is a key element of gastric cancer treatment. The Maruyama Computer Program (MCP) allows to predict lymph node involvement in stations no. 1-16. The aim of the current study was to evaluate the accuracy of the MCP predictions in GC patients treated with neoadjuvant chemotherapy (nCTH) followed by gastrectomy with adequate lymphadenectomy.

METHODS

101 patients who underwent preoperative nCTH followed by D2 gastrectomy with curative intent were analysed. The response to nCTH was measured using the tumour regression grade system.

RESULTS

Test sensitivity, specificity, PPV, NPV and accuracy of the MCP were 92%, 33%, 41%, 89%, and 53%, respectively. In patients with response to nCTH, number of false positive (FP) results was significantly higher than in patients who did not respond to nCTH both in the N1 (56.3% vs 28.9%, p < 0.0001) and in the N2 (59% vs 41%, p < 0.0001) trier. The risk for FP results was 6 times higher in N1 (OR = 6.50, 95%CI: 3.91-10.82,; p < 0.0001) and N2 (OR = 5.84, 95%CI: 2.85-11.96; p < 0.0001) triers. In patients with intestinal type GC, the risk for FP results was 4 times higher than in other histologic types of GC in both N1 (OR = 4.23, 95%CI: 2.58-6.95; p < 0.0001) and N2 (OR = 4.23, 95%CI: 2.02-9.62; p = 0.0002) triers.

CONCLUSIONS

MCP predictions in the GC patients treated with nCTH have low specificity due to significantly high number of FP results. Noticeably low accuracy level of predictions indicate a need for new prediction models, based on Laurén classification, since it may provide some information on expected regression grade.

CT-Detected Extramural Vessel Invasion and Regional Lymph Node Involvement in Stage T4a Gastric Cancer for Predicting Progression-Free Survival

OBJECTIVE. This study aimed to investigate the 3-year progression-free survival (PFS) of patients with stage T4a gastric cancer with extramural vessel invasion (EMVI) detected with contrast-enhanced (CE) MDCT. In addition, we investigated the possibility that CT of EMVI could improve clinical nodal (N) staging. MATERIALS AND METHODS. This retrospective study included 143 patients with T4a gastric cancer. Clinical staging was performed with CE-MDCT. All patients underwent radical gastrectomy with extended lymphadenectomy, adjuvant chemotherapy, and conventional follow-up visits. Potential prognostic factors, including CE-MDCT-detected N status, pathologic N status, EMVI detected at CT, tumor location or growth pattern, histologic type or tumor differentiation, and tumor size, were recorded. Survival estimates for PFS were obtained using the Kaplan-Meier product limit for the following patient subgroups: EMVI positive-N positive, EMVI positive-N negative, EMVI negative-N positive, and EMVI negative-N negative. Hazard ratios for 3-year PFS were generated using a Cox proportional hazard regression analysis. RESULTS. The frequency of EMVI detected at CT was 55.9% (80/143). The 3-year PFS rates were 25.0% for the EMVI positive-N positive group, 53.1% for the EMVI positive-N negative group, 75.6% for the EMVI negative-N positive group, and 64.7% for the EMVI negative-N negative group. The EMVI positive-N positive subgroup 3-year PFS rate was significantly lower than that of the other three groups (p < 0.05, log-rank test). Using Cox proportional hazards regression analysis, EMVI positive-N positive status was found to be an independent factor for reduced 3-year PFS, with a hazard ratio of 2.169 (95% CI, 1.300-3.618; p = 0.003). CONCLUSION. EMVI detected at CT, combined with N status detected with CE-MDCT, could be used as a valuable preoperative prognostic factor in patients with T4a gastric cancer.

Different prognostic implication of ypTNM stage and pTNM stage for gastric cancer: a propensity score-matched analysis

Background

Pathological stage is considered as the best prognosis indicator for gastric cancer. With the increasing use of neoadjuvant chemotherapy (NACT), the latest TNM staging included a new pathological stage of ypTNM for patients with NACT. However, no study has investigated if ypTNM stage has the same prognostic implication as pTNM stage for gastric cancer.

Methods

We retrospectively selected eligible patients within a prospectively maintained database containing all patients treated with gastric cancer in Peking University Cancer Hospital from 2007 to 2015 using overall survival as the outcome. Patients using ypTNM and pTNM were 1:1 matched by propensity scores (PS) calculated from a model containing variables associated with ypTNM use or survival. Overall survival was compared by unconditional Cox regression. Conventional multivariate analysis was conducted to corroborate PS matching results.

Results

1441 patients were included in the analysis with a median follow-up of 37 months (range = 2–106). The matched sample contained 756 patients. After PS matching, patients with specific ypTNM stage were 1.34 (95%CI = 1.05–1.72, P = 0.019) times more likely to die than patients with the same pTNM stage. Similar to the results of PS matching, multivariate Cox regression yielded a hazard ratio (HR) of 1.35 (95%CI = 1.09–1.67, P = 0.006). Subgroup analysis indicated this survival difference between ypTNM and pTNM stage varied by the specific TNM stage of patients. The HR was 3.44 (95%CI = 1.06–11.18, P = 0.040) and 1.28 (95%CI = 1.00–1.62, P = 0.048) for patients in stage I and III, respectively; whereas for stage II patients, no significant difference was observed (HR = 1.37, 95%CI = 0.78–2.38, P = 0.27).

Conclusion

Gastric cancer patients with specific ypTNM stage had worse prognosis compared to those at the same stage defined by pTNM.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5283-3) contains supplementary material, which is available to authorized users.

miR‑3664‑5P suppresses the proliferation and metastasis of gastric cancer by attenuating the NF‑κB signaling pathway through targeting MTDH

Gastric cancer (GC) is one of the most common and fatal types of cancers worldwide and the specific mechanism has not been completely elucidated. microRNA (miR)‑3664‑5P has rarely been studied and the aim of the present study was to assess an association between miR‑3664‑5P and GC. Differences in miR‑3664‑5P expression in 100 GC (0.1846±0.08276) and paired normal tissues (0.4382±0.1595) were detected using reverse transcription‑quantitative polymerase chain reaction assays (P<0.001). 5‑Ethynyl‑2‑deoxyuridine, Cell Counting Kit‑8, transwell and flow cytometry assays were performed in vitro and the results were further verified using a mouse xenotransplantation and a lung metastasis model in vivo. miR‑3664‑5P was significantly downregulated in GC tissues when compared with normal tissues and positively associated with the prognosis of patients with GC (P<0.001). Overexpression of miR‑3664‑5P suppressed and miR‑3664‑5P knockdown promoted the proliferation and metastasis of GC cells in vitro and in vivo. Following the application of bioinformatic algorithms and luciferase reporter assays, metadherin (MTDH) was confirmed as the target gene of miR‑3664‑5P. miR‑3664‑5P reduced MTDH expression and downregulated the nuclear factor (NF)‑κB signaling pathway. Rescue experiments demonstrated that suppression of MTDH restored the effect of miR‑3664‑5P inhibitors on GC cell lines. The results suggested that miR‑3664‑5P suppressed the proliferation and metastasis of GC cells by attenuating the NF‑κB signaling pathway via MTDH targeting. Consequently, miR‑3664‑5P may have potential to be an independent prognostic factor and biomarker in GC.

Current challenges in gastric cancer surgery: European perspective

Gastric cancer (GC) remains one of the most common causes of cancer death worldwide with expected 5-year survival rates around 25% in Western countries. In order to improve treatment strategy, a most effective staging process should be completed. A novel TNM staging for GC has been proposed recently, along with a separate staging system for GC patients who underwent preoperative therapy (ypStage). Availability of high-quality imaging and access to diagnostic laparoscopy with lavage cytology should be applied while planning the multimodal therapy. In the European setting, GC treatment is based on a combination of surgery and perioperative chemotherapy. However, in selected groups of patients with high risk of locoregional recurrence, adjuvant chemoradiotherapy should be considered. New epidemiological trends of GC in the Western countries include an upward shift in the location of the primary tumour and a relative increase of advanced and diffuse type tumours. These trends dictate modification of surgical techniques towards a more individualized GC treatment approach.

Central Lymph Node Metastasis in Gastric Cancer Is Predictive of Survival After Preoperative Therapy

BACKGROUND

It is unclear how preoperative therapy for gastric cancer affects the metastasis rate of lymph nodes (LNs) and whether the location of positive LNs affects survival after preoperative therapy. Therefore, we determined the association between positive central lymph nodes (CnLNs) and disease stage and overall survival (OS).

METHODS

We reviewed a prospectively maintained database to identify patients who had undergone resection of gastric adenocarcinoma at our institution from 2005 to 2015. CnLNs were defined as common hepatic, celiac, and proximal splenic artery LNs (stations no. 8, 9, and 11p). The frequency of CnLN metastases and risk factors affecting OS were examined.

RESULTS

We identified 356 patients. Preoperative therapy was administered to 66% of patients. D2 LN dissection was performed in 80% of patients, and the median number of LNs examined was 25 (IQR, 18-34). In 243 patients (68%), CnLNs had undergone separate pathologic examination; the CnLN-positive rate was 9.1% (22 of 243; station no. 8, 4.5%; no. 9, 2.1%; and no. 11p, 4.8%). CnLN metastasis was associated with shorter 3-year OS in patients with pN2/3 disease (33 vs. 62%; p = 0.004). Among patients who had undergone preoperative therapy, ypT3-4 stage (HR 2.44; p = 0.01) and positive CnLNs (HR 5.44; p < 0.001) were negatively associated with OS by multivariate analysis.

CONCLUSIONS

CnLN metastases are uncommon in gastric cancer and have an adverse effect on OS in patients who have undergone preoperative therapy. Larger multi-institutional studies are needed to determine whether CnLN positivity requires a separate staging category after preoperative therapy.

The ypT category does not impact overall survival in node negative gastric cancer

BACKGROUND

Although the eighth-edition American Joint Committee on Cancer (AJCC) gastric cancer staging system created ypTNM staging for patients who underwent preoperative therapy, the ideal ypTNM grouping is unknown. We sought to investigate risk factors for OS in ypT0-3N0M0 gastric cancer.

METHODS

From an institutional database of The University of Texas MD Anderson Cancer Center and the National Cancer Database (NCDB), we identified patients with ypT0-3N0M0 gastric adenocarcinoma who underwent R0 gastrectomy after chemotherapy or chemoradiation during 1995-2015 (MD Anderson) or 2006-2014 (NCDB).

RESULTS

The study included 175 MD Anderson and 3200 NCDB patients. By multivariable analysis, ypT category was not associated with OS (hazard ratio [HR] for ypT3 vs ypT1: MD Anderson, 0.83 [95% CI, 0.36-1.92], P = 0.669; NCDB, 0.96 [95% CI, 0.85-1.08], P = 0.472). cN-positive disease was not associated with OS in the MD Anderson cohort (HR, 0.96 [95% CI, 0.55-1.67]; P = 0.873) but was weakly associated with shorter OS in the NCDB cohort (HR, 1.11 [95% CI, 1.01-1.21]; P = 0.031).

CONCLUSIONS

The ypT category does not impact OS in ypT0-3N0M0 gastric cancer. The impact of cN status on OS appeared limited. These findings should be considered in future systems of post-neoadjuvant pathologic staging.

Unplanned reoperation after radical gastrectomy for gastric cancer: causes, risk factors, and long-term prognostic influence

Purpose

Unplanned reoperation (URO) after radical gastrectomy for gastric cancer (GC) mostly results from serious postoperative complications. At present, there is still controversy over the predictive factors for URO. Our goal was to identify the risk factors for URO and to investigate its potential impact on long-term survival.

Patients and methods

We included 2,852 GC patients who underwent a gastrectomy. Multivariate logistic regression analyses were performed to determine the risk factors for URO. Patients were randomly selected from the non-URO group by 1:4 propensity score matching with multiple parameters with patients from the URO group. The survival disparity of 34 URO patients and 136 non-URO patients was examined using the Kaplan-Meier method and the multivariate Cox proportional hazard model.

Results

The incidence of URO was 1.4% (39/2, 852). The primary cause of URO was intra-abdominal bleeding (53.9%, 21/39). Multivariate logistic regression analyses revealed that male gender (OR = 4.630, 95% CI = 1.412-15.152, P = 0.011), diabetes (OR = 4.189, 95% CI = 1.705-10.290, P = 0.002), and preoperative hypoproteinemia (OR = 2.305, 95% CI = 1.079-4.923, P = 0.031) were independent risk factors for URO. With regard to early surgical outcomes, patients undergoing URO had a longer hospital stay (P < 0.001), higher incidence of postoperative complications (P < 0.001), and greater mortality (P < 0.001) compared with the non-URO group. No significant correlation was found between URO and cancer-specific survival in univariate (P = 0.275) and multivariate (P = 0.090) survival analyses.

Conclusion

Male gender, diabetes, and preoperative hypoproteinemia were suggested as independent risk factors for URO. URO was associated with longer hospital stay and increased perioperative mortality, but might not be correlated with long-term mortality.

Nodal Downstaging in Gastric Cancer Patients: Promising Survival if ypN0 is Achieved

BACKGROUND

The American Joint Committee on Cancer's 8th edition introduced ypStage, a separate staging system for patients with gastric cancer having undergone preoperative therapy. Overall, ypN0 patients have better survival outcomes than ypN+ patients. However, whether patients with cN+/ypN0 disease ("downstaged N0") and those with cN0/ypN0 disease ("natural N0") have similar survival is unknown.

METHODS

An institutional database was reviewed to identify gastric adenocarcinoma patients who underwent potentially curative R0 resection after induction chemotherapy or chemoradiation. Patients were categorized into three groups based on nodal status: cN0/ypN0, cN+/ypN0, and ypN+. Univariable and multivariable Cox regression models were used to identify clinicopathologic factors associated with overall survival (OS).

RESULTS

We identified 316 patients who met the study criteria. Ninety-four patients (30%) had cN0/ypN0 disease, 93 (29%) had cN+/ypN0 disease, and 129 (41%) had ypN+ disease. The median OS was 7.7 years, and the 5-year OS was 60.3%. In the multivariate analysis, OS did not differ between the cN0/ypN0 and cN+/ypN0 patients (hazard ratio, 0.90 [95% CI 0.54-1.48]; p = 0.666), but it was shorter in ypN+ patients (hazard ratio, 1.82 [95% CI 1.15-2.87]; p = 0.01).

CONCLUSIONS

In gastric cancer patients who underwent preoperative therapy, we found similar OS in cN0/ypN0 and cN+/ypN0 patients. Because ypN+ patients had poor OS, achieving ypN0 status is an important hallmark demonstrating the effectiveness of preoperative therapy for gastric cancer.

Treatment of localized gastric and gastroesophageal adenocarcinoma: the role of accurate staging and preoperative therapy

Gastric cancer is the third most common cause of cancer death worldwide, although it is not in the top 10 causes of cancer death in Northern America. Due to clear differences in incidence, screening, risk factors, tumor biology, and treatment between gastric cancers from Eastern and Western countries, our treatment is primarily guided by trials from Western countries. Patients undergo an extensive staging evaluation including high-quality CT imaging, endoscopic ultrasound, and diagnostic laparoscopy with peritoneal washings for cytology. Patients are presented in multidisciplinary conference with input from medical, radiation, and surgical oncology, in addition to further evaluation of existing studies and biopsy results by diagnostic radiology and pathology colleagues. Due to the well-documented difficulty in tolerating postoperative therapy, patients are frequently treated with preoperative chemotherapy and chemoradiotherapy. Extended lymph node (D2) dissection is routinely performed during subtotal or total gastrectomy. Ongoing trials in Western populations comparing preoperative chemotherapy to chemoradiotherapy will help inform the decision regarding the optimal treatment for patients with resectable gastric cancer. Additional studies are needed to identify predictors of treatment response to identify the optimal preoperative or perioperative approach. As peritoneal disease is the most common site of recurrence, studies are also urgently needed for more accurate methods of detecting peritoneal disease at diagnosis, and also investigating potential treatment modalities such as hyperthermic intraperitoneal chemotherapy.

Preoperative Chemoradiation Therapy Does Not Increase Risk of Anastomotic Leak in Patients With Gastric Cancer

INTRODUCTION

We sought to determine whether preoperative chemoradiation therapy or chemotherapy increases the risk of anastomotic leak after gastrectomy in gastric cancer patients without gastroesophageal junction involvement.

METHODS

We reviewed data from a prospectively maintained database of patients who underwent gastrectomy at our institution between 2001 and 2016. The incidence of anastomotic leak and symptomatic intra-abdominal fluid collection was determined and tested for associations with the type of preoperative therapy. Risk factors for these adverse events were identified by univariate and multivariable logistic regression models.

RESULTS

Of 346 included patients, 35% had upfront surgery, 44% had preoperative chemoradiation therapy, and 21% had preoperative chemotherapy. Anastomotic leak and intra-abdominal fluid collection were diagnosed in 3.5% and 7.5% of patients, respectively. Multivariable analysis revealed that concomitant organ resection was the only significant risk factor for anastomotic leak or intra-abdominal fluid collection (P=.014). The type of preoperative therapy was not a risk factor for anastomotic leak or intra-abdominal fluid collection.

CONCLUSIONS

Anastomotic leak and intra-abdominal fluid collection were rare after gastrectomy, and neither type of preoperative therapy increased the risk of these adverse events. Our results add to the existing literature that preoperative therapy, including preoperative chemoradiation therapy, is safe for patients with gastric cancer.