Individualized proximal margin correlates with outcomes in gastric cancers with radical gastrectomy

A shorter distal resection margin is a surrogate marker of nodal metastasis and poor prognosis in distal gastrectomy for advanced gastric cancer

BACKGROUND

Although a 3-5 cm surgical margin distance is recommended for advanced gastric cancer (GC) in Japanese guidelines, little is known about the clinical effects of the surgical margin, especially the distal resection margin (DM). This study aims to clarify the clinical significance of DM in GC.

METHODS

A total of 415 GC patients who underwent curative distal gastrectomy between 2008 and 2018 were analyzed retrospectively.

RESULTS

The DM significantly stratified recurrence-free survival (P = 0.002), and a DM < 30 mm was an independent factor of a poor prognosis (P = 0.023, hazard ratio: 1.91). Lymphatic recurrence occurred significantly more frequently in the DM < 30 mm group than in the DM ≥ 30 mm group (P = 0.019, 6.9% vs. 1.9%). Regarding the station No.6 lymph node metastases in advanced GC (DM < 30 mm vs. 30 mm ≤ DM ≤ 50 mm vs. DM > 50 mm), the number (P < 0.001, 1.42 ± 1.69 vs. 1.18 ± 1.80 vs. 0.18 ± 0.64), the positive rate (P < 0.001, 59.0% vs. 46.7% vs. 11.3%) and therapeutic value index (43.3 vs. 14.5 vs. 8.0) were significantly higher in the DM < 30 mm group. By subdivision using the DM distance of 30 mm, more segmented prognostic stratifications were possible (P < 0.001).

CONCLUSIONS

A DM of less than 30 mm could be a surrogate marker of poor RFS, especially increasing nodal recurrence. More intensive treatment strategies, including lymphadenectomy and chemotherapy, are needed for patients with this condition.

A systematic review of minimal length of lroximal margin in gastric adenocarcinoma resection

For early distal gastric cancers, a proximal margin (PM) > 2-3 cm might probably be sufficient. For advanced tumors, many confounding factors have a prognostic impact on survival and recurrence and negative margin involvement may be more relevant than negative margin length.

INTRODUCTION

In gastric cancer surgery, microscopic positive margin is a poor prognostic factor whereas complete resection with tumor-free margins remains a challenging issue. European guidelines recommended a macroscopic margin of 5 or even 8 cm for diffuse-type cancers to achieve R0 resection. However, it is unclear if the length of negative proximal margin (PM) could have a prognostic impact on survival. We aimed to perform a systematic review of the literature analyzing PM length and its prognostic impact in gastric adenocarcinoma.

MATERIAL AND METHODS

Pubmed and Embase databases were searched for "gastric cancer" or "gastric adenocarcinoma," combined with "proximal margin," between January 1990 and June 2021. English-written studies that specified PM length were included. Survival data, in relation to PM, were extracted.

RESULTS

Twelve retrospective studies, with a total number of 10,067 patients, met inclusion criteria and were analyzed. Mean length of proximal margin on the whole population varied from 2.6 to 5.29 cm. Three studies found minimal PM cut-off to improve overall survival in univariate analysis. Concerning recurrence-free survival analysis, only 2 series showed better results with PM > 2 or > 3 cm, using Kaplan-Meier method. Multivariate analysis demonstrated an independent impact of PM on overall survival in 2 studies.

CONCLUSION

For early distal gastric cancers, a PM > 2-3 cm might probably be sufficient. For advanced or proximal tumors, many confounding factors have a prognostic impact on survival and recurrence and negative margin involvement may be more relevant than negative margin length.

Current standards of surgical management of gastric cancer: an appraisal

PURPOSE

Gastric cancer (GC) is the fifth most common malignancy worldwide and portends a grim prognosis due to a lack of appreciable improvement in 5-year survival. We aimed to analyze the available literature and summarize the current standards of surgical care for curative and palliative intent treatment of GC.

METHODS

We conducted a systematic search on the PubMed database for studies on the management of GC.

RESULTS

Endoscopic resection is an acceptable treatment option for T1a tumors. The role of optimal resection margin for GC remains unclear. D2 lymph node dissection remains the standard of care with splenectomy needed selectively for splenic hilum involvement. A distal pancreatic resection should be avoided. The advantage of bursectomy and omentectomy in GC surgery is not clear. Multi-visceral resection may be considered for locally advanced GC in carefully selected patients. Minimally invasive approaches are non-inferior to open surgery. Surgery should be abandoned prior even in metastatic GC within the frame of multimodal therapy approach.

CONCLUSION

Various trials have conclusively shown improved patient outcomes when well-established surgical standards are followed.

The Role of Surgery in the Management of Gastric Cancer: State of the Art

Surgery still represents the mainstay of treatment of all stages of gastric cancer (GC). Surgical resections represent potentially curative options in the case of early GC with a low risk of node metastasis. Sentinel lymph node biopsy and indocyanine green fluorescence are novel techniques which may improve the employment of stomach-sparing procedures, ameliorating quality of life without compromising oncological radicality. Nonetheless, the diffusion of these techniques is limited in Western countries. Conversely, radical gastrectomy with extensive lymphadenectomy and multimodal treatment represents a valid option in the case of advanced GC. Differences between Eastern and Western recommendations still exist, and the optimal multimodal strategy is still a matter of investigation. Recent chemotherapy protocols have made surgery available for patients with oligometastatic disease. In this context, intraperitoneal administration of chemotherapy via HIPEC or PIPAC has emerged as an alternative weapon for patients with peritoneal carcinomatosis. In conclusion, the surgical management of GC is still evolving together with the multimodal strategy. It is mandatory for surgeons to be conscious of the current evolution of the surgical management of GC in the era of multidisciplinary and tailored medicine.

Bacterial Involvement in Progression and Metastasis of Adenocarcinoma of the Stomach

Simple Summary

Infectious bacteria influence primary gastric carcinogenesis, organotropism, and metastatic progression by altering the microenvironment at the primary and secondary tumors. Key species include Helicobacter pylori (H. pylori) and Mycoplasma hyorhinis (M. hyorhinis). Inflammation caused by H. pylori virulence factors, such as CagA, VacA, and oipA, disrupt epithelial integrity, which allows the primary tumor to progress through the metastatic process. Evidence supports the activation of aquaporin-5 by CagA-positive H. pylori infection, promoting epithelial–mesenchymal transition via the extracellular signal-regulated kinase/mitogen-activated protein kinase (MEK/ERK) pathway, thus laying the foundation for metastatic disease. M. hyorhinis has also been implicated in gastric neoplasia via β-catenin stabilization and subsequent activation of the WNT-signaling pathway, promoting gastric cancer cell motility and inciting cancer progression.

Abstract

Gastric cancer metastasis is a process in which the tumor microenvironment may carry significant influence. Helicobacter pylori (H. pylori) infection is well-established as a contributor to gastric carcinoma. However, the role that these bacteria and others may play in gastric carcinoma metastasis is a current focus of study. A review of the literature was conducted to elucidate the process by which gastric adenocarcinoma metastasizes, including its ability to utilize both the lymphatic system and the venous system to disseminate. Studies that investigate the tumor microenvironment at both the primary and secondary sites were assessed in detail. H. pylori and Mycoplasma hyorhinis (M. hyorhinis) were found to be important drivers of the pathogenesis of gastric adenocarcinoma by modifying various steps in cell metastasis, including epithelial–mesenchymal transition, cell migration, and cell invasion. H. pylori is also a known driver of MALT lymphoma, which is often reversible simply with the eradication of infection. M. hyorhinis has been implicated in gastric neoplasia via β-catenin stabilization and subsequent activation of the WNT-signaling pathway, promoting gastric cancer cell motility and inciting cancer progression. Fusobacterium nucleatum (F. nucleatum) and its association with worse prognosis in diffuse-type gastric adenocarcinoma are also reviewed. Recognition of the roles that bacteria play within the metastatic cascade is vital in gastrointestinal adenocarcinoma treatment and potential reoccurrence. Further investigation is needed to establish potential treatment for metastatic gastric carcinoma by targeting the tumor microenvironment.

Impact of Surgical Margins on Overall Survival after Gastrectomy for Gastric Cancer: A Validation of Japanese Gastric Cancer Association Guidelines on a Western Series

Purpose

No consensus exists on the resection extent needed to ensure oncological safety in gastrectomy for gastric adenocarcinoma (GAC). This study aims to assess the impact of margin adequacy according to Japanese Gastric Cancer Association (JGCA) guidelines on overall survival (OS).

Patients and Methods

Patients who underwent surgery for stage I–III GAC at our institution between 2010 and 2017 were included. Margin adequacy according to JGCA, National Comprehensive Cancer Network (NCCN), and European Society for Medical Oncology (ESMO) guidelines was assessed, and their predictive value on OS was evaluated with Harrell’s C-index. Patients were analyzed according to their margins’ adherence to JGCA guidelines, and a propensity score matching (PSM) was run. Indication to either total gastrectomy (TG) or distal gastrectomy (DG) according to each guideline was also assessed.

Results

A total of 279 patients were included, of whom 220 (79%) underwent DG. Adequate margins according to JGCA were obtained in 209 patients (75%). On multivariate analysis, JGCA margin adequacy was independently associated with OS, together with American Society of Anesthesiologist class, neoadjuvant chemotherapy, lymphadenectomy extent, R0 resection, and postoperative N stage. After PSM, patients with JGCA adequate margins showed better OS, recurrence-free survival (RFS), and local RFS than patients with JGCA inadequate margins. For 220 DG, JGCA guidelines would have recommended TG in 25 patients (11%), NCCN in 30 (14%), and ESMO in 90 (41%) (p < 0.001).

Conclusion

Adequacy of surgical resection margins to JGCA guidelines leads to improved survival outcomes and allows for a more organ-preserving approach than Western guidelines.

Optimal proximal resection margin distance for gastrectomy in advanced gastric cancer

BACKGROUND

The conventional guidelines to obtain a safe proximal resection margin (PRM) of 5-6 cm during advanced gastric cancer (AGC) surgery are still applied by many surgeons across the world. Several recent studies have raised questions regarding the need for such extensive resection, but without reaching consensus. This study was designed to prove that the PRM distance does not affect the prognosis of patients who undergo gastrectomy for AGC.

AIM

To investigate the influence of the PRM distance on the prognosis of patients who underwent gastrectomy for AGC.

METHODS

Electronic medical records of 1518 patients who underwent curative gastrectomy for AGC between June 2004 and December 2007 at Asan Medical Center, a tertiary care center in Korea, were reviewed retrospectively for the study. The demographics and clinicopathologic outcomes were compared between patients who underwent surgery with different PRM distances using one-way ANOVA and Fisher’s exact test for continuous and categorical variables, respectively. The influence of PRM on recurrence-free survival and overall survival were analyzed using Kaplan-Meier survival analysis and Cox proportional hazard analysis.

RESULTS

The median PRM distance was 4.8 cm and 3.5 cm in the distal gastrectomy (DG) and total gastrectomy (TG) groups, respectively. Patient cohorts in the DG and TG groups were subdivided into different groups according to the PRM distance; ≤ 1.0 cm, 1.1-3.0 cm, 3.1-5.0 cm and > 5.0 cm. The DG and TG groups showed no statistical difference in recurrence rate (23.5% vs 30.6% vs 24.0% vs 24.7%, P = 0.765) or local recurrence rate (5.9% vs 6.5% vs 8.4% vs 6.2%, P = 0.727) according to the distance of PRM. In both groups, Kalpan-Meier analysis showed no statistical difference in recurrence-free survival (P = 0.467 in DG group; P = 0.155 in TG group) or overall survival (P = 0.503 in DG group; P = 0.155 in TG group) according to the PRM distance. Multivariate analysis using Cox proportional hazard model revealed that in both groups, there was no significant difference in recurrence-free survival according to the PRM distance.

CONCLUSION

The distance of PRM is not a prognostic factor for patients who undergo curative gastrectomy for AGC.

Analysis of survival and prognosis of 298 gastric adenocarcinoma patients with no distant metastasis

This study investigated the survival and prognosis of 298 gastric adenocarcinoma patients with no distant metastasis. For analysis and comparison of the prognosis of patients, a retrospective analysis was performed in 298 patients with perfect clinical data and follow-up data who received the D2 resections for gastric cancer in Shandong Provincial Hospital Affiliated to Shandong University between January, 2005 and January, 2012, and were diagnosed as gastric adenocarcinoma with no distant metastasis in postoperative pathological examination. Among the gastric adenocarcinoma patients without distant metastasis, we found that differences of sex, age, differentiation and position of tumor had no statistical significance (P>0.05), while comparisons of the tumor diameter, regional lymphatic metastasis, vascular invasion and pathological TNM stages (pTNM; T for tumor, N for lymph node and M for metastasis) showed statistical significance (P<0.05). One-way analysis of variance (ANOVA) indicated the correlation between the prognosis of gastric adenocarcinoma patients and tumor diameter, regional lymphatic metastasis, vascular invasion and pTNM stages of patients (P<0.05). Multivariate analysis of Cox regression models was performed for discovering the factors associated with the prognosis of patients, and the results suggested that position of tumor (P=0.016), regional lymphatic metastasis (P=0.042), vascular invasion (P=0.021) and pTNM stage (P=0.009) were the independent risk factors affecting the prognosis of gastric adenocarcinoma patients. During 60-month follow-up, the median survival duration of gastric adenocarcinoma patients with no distant metastasis was 38 months, while the 5-year accumulate survival rate was 49.3%. The results indicated that in gastric adenocarcinoma patients without distant metastasis, tumor diameter, regional lymphatic metastasis, vascular invasion and pTNM stage are major indicators affecting the prognosis of patients.