Survival after surgical treatment of early gastric cancer, surgical techniques, and long-term survival

Inflammatory microenvironment in gastric premalignant lesions: implication and application

Gastric precancerous lesions (GPL) are a major health concern worldwide due to their potential to progress to gastric cancer (GC). Understanding the mechanism underlying the transformation from GPL to GC can provide a fresh insight for the early detection of GC. Although chronic inflammation is prevalent in the GPL, how the inflammatory microenvironment monitored the progression of GPL-to-GC are still elusive. Inflammation has been recognized as a key player in the progression of GPL. This review aims to provide an overview of the inflammatory microenvironment in GPL and its implications for disease progression and potential therapeutic applications. We discuss the involvement of inflammation in the progression of GPL, highlighting Helicobacter pylori (H. pylori) as a mediator for inflammatory microenvironment and a key driver to GC progression. We explore the role of immune cells in mediating the progression of GPL, and focus on the regulation of inflammatory molecules in this disease. Furthermore, we discuss the potential of targeting inflammatory pathways for GPL. There are currently no specific drugs for GPL treatment, but traditional Chinese Medicine (TCM) and natural antioxidants, known as antioxidant and anti-inflammatory properties, exhibit promising effects in suppressing or reversing the progression of GPL. Finally, the challenges and future perspectives in the field are proposed. Overall, this review highlights the central role of the inflammatory microenvironment in the progression of GPL, paving the way for innovative therapeutic approaches in the future.

Dynamic gene screening enabled identification of a 10-gene panel for early detection and progression assessment of gastric cancer

Early diagnosis and progression assessment are critical for the timely detection and treatment of gastric cancer (GC) patients. Identification of diagnostic biomarkers for early detection of GC represents an unmet clinical need, and how these markers further influence GC progression is explored rarely. We performed dynamic gene screening based on high-throughput data analysis from patients with precancerous lesions and early gastric cancer (EGC) and identified a 10-gene panel by the lasso regression model. This panel demonstrated good diagnostic performance in TCGA (AUC = 0.95, sensitivity = 86.67 %, specificity = 90.63 %) and GEO (AUC = 0.84, sensitivity = 91.67 %, specificity = 78.13 %) cohorts. Moreover, three GC subtypes were clustered based on this panel, in which cluster 2 (C2) demonstrated the highest tumor progression level with a high expression of 10 genes, showing a decreased tumor mutation burden, significantly enriched epithelial-mesenchymal transition hallmark and increased immune exclusion/exhausted features. Finally, the cell localization of these panel genes was explored in scRNA-seq data based on more than 40,000 cells. The 10-gene panel is expected to be a new clinical early detection signature for GC and may aid in progression assessment and personalized treatment of patients.

A cohort study using IL-6/Stat3 activity and PD-1/PD-L1 expression to predict five-year survival for patients after gastric cancer resection

OBJECTIVES

The expression/activation of IL-6, p-Stat3, PD-1 and PD-L1 in gastric cancer (GC) tissues were examined to evaluate their abilities in predicting the survival prognosis in postoperative patients with GC.

METHODS

The clinicopathological data and paraffin-embedded tissues of 205 patients who underwent gastric cancer resection were collected at the First Affiliated Hospital of Shihezi University School of Medicine, and the patients were followed-up annually after surgery. Immunohistochemistry (IHC) was used to detect the expression of IL-6, p-Stat3, PD-1 and PD-L1 proteins using tissue microarrays derived from these patients. Statistical analyses were performed using non-parametric tests, Spearman's correlation, ROC curves, Kaplan-Meier survival analysis, Cox single-factor and multifactor regression models. In comparison, the analyses were also performed for GC patients from public databases (407 patients from TCGA and 433 patients from GEO, respectively).

RESULTS

(1) The expression levels of IL-6, p-Stat3, PD-1 and PD-L1 in GC tissues were significantly higher than adjacent normal tissues (ANT) (81.01% vs. 52.78%, P<0.001; 100% vs. 93.41%, P<0.001; 58.58% vs. 40.12%, P<0.001; 38.20% vs. 26.90%, P = 0.025, respectively). The mean optical density (MOD) values of IL-6, p-Stat3, PD-1 and PD-L1 were significantly higher in GC tissues. (2) The higher the levels of IL-6 (P<0.001), p-Stat3 (P<0.001), and PD-L1 (P = 0.003) were, the worse the survival prognoses were observed, respectively, among GC patients. The expression of PD-1 was not correlated with the prognosis of GC patients (P>0.05). The lower the degree of cell differentiation (P<0.001) was, the worse the survival prognoses were observed among GC patients. (3) Independent risk factors for postoperative prognosis in GC patients included age (≥60 years old), poor cell differentiation, invasion depth (T3/T4), lymph node metastasis (N1-3), distant metastasis (M1), and high levels of IL-6 (2+/3+). (4) A multi-factor combination (cell differentiation+IL-6+p-Stat3+PD-1+PD-L1) appeared to be the best survival predictor for GC patients as indicated by AUC (AUC 0.782, 95% CI = 0.709, 0.856, P<0.001). This combination may be the optimal predictor for postoperative survival of GC patients. (5) The levels of IL-6, p-Stat3, PD-1 and PD-L1 correlated with the infiltration levels of various tumor-infiltrating immune cells. (6) The analyses of ROC curves, calibration, DCA and Kaplan-Meier (KM) survival curves in TCGA dataset confirmed that the nomogram model could accurately predict the prognosis in GC patients.

CONCLUSIONS

(1) The expressed levels of IL-6, p-Stat3, PD-1 and PD-L1 are higher in GC tissues than in adjacent normal tissues. (2) The high levels of IL-6, p-Stat3 and PD-L1 are correlated with poor survival in GC patients. (3) The high levels of IL-6, p-Stat3, PD-1 and PD-L1 have influences in GC tumor microenvironment. (4) The multi-predictor combination of "IL-6+p-Stat3+PD-1+cell differentiation" serves as an optimal survival predictor for postoperative GC patients and better than the TNM staging system. As these molecules can be examined in preoperative biopsies, these observations may provide a useful guide for clinicians to strategize individualized surgical plans for GC patients before surgery.

Effect of hyperthermic intraperitoneal chemotherapy for gastric cancer patients: a meta-analysis of the randomized controlled trials

Objective

To determine the effectiveness and safety of hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with advanced gastric cancer and peritoneal metastases.

Methods

PubMed®, CNKI, Web of Science, VIP and WANFANG databases were searched to identify randomized controlled trials (RCTs) that examined the effect of HIPEC on survival, clinical response and adverse events. Patients with advanced gastric cancer and peritoneal metastases were divided into an experimental group and a control group. The statistical results are presented as relative ratio (RR), mean difference (MD) and 95% confidence interval (CI).

Results

Twenty-one RCTs met the inclusion criteria (n = 1674 patients). Meta-analysis showed that the 3-year survival rate was significantly higher in the HIPEC group than in the control group (RR 1.61; 95% CI 1.43, 1.82) and the complete response rate was significantly higher in the HIPEC group than in the control group (RR 2.35; 95% CI 1.67, 3.31). HIPEC was also beneficial in terms of decreased CEA (MD −1.79; 95% CI −2.22, −1.35). There was no significant difference in the rate of adverse reactions (RR 1.00; 95% CI 0.87, 1.14).

Conclusions

HIPEC had a beneficial effect on 3-year survival rate and complete response in patients with advanced gastric cancer and peritoneal metastases.

SURVIVAL AND PERIOPERATIVE MORBIDITY OF TOTALLY LAPAROSCOPIC VERSUS OPEN GASTRECTOMY FOR EARLY GASTRIC CANCER: ANALYSIS FROM A SINGLE LATIN AMERICAN CENTRE

BACKGROUND

Laparoscopic gastrectomy has numerous perioperative advantages, but the long-term survival of patients after this procedure has been less studied.

AIM

To compare survival, oncologic and perioperative outcomes between completely laparoscopic vs. open gastrectomy for early gastric cancer.

METHODS

This study was retrospective, and our main outcomes were the overall and disease-specific 5-year survival, lymph node count and R0 resection rate. Our secondary outcome was postoperative morbidity.

RESULTS

Were included 116 patients (59% men, age 68 years, comorbidities 73%, BMI 25) who underwent 50 laparoscopic gastrectomies and 66 open gastrectomies. The demographic characteristics, tumour location, type of surgery, extent of lymph node dissection and stage did not significantly differ between groups. The overall complication rate was similar in both groups (40% vs. 28%, p=ns), and complications graded at least Clavien 2 (36% vs. 18%, p=0.03), respiratory (9% vs. 0%, p=0.03) and wound-abdominal wall complications (12% vs. 0%, p=0.009) were significantly lower after laparoscopic gastrectomy. The lymph node count (21 vs. 23 nodes; p=ns) and R0 resection rate (100% vs. 96%; p=ns) did not significantly differ between groups. The 5-year overall survival (84% vs. 87%, p=0.31) and disease-specific survival (93% vs. 98%, p=0.20) did not significantly differ between the laparoscopic and open gastrectomy groups.

CONCLUSION

The results of this study support similar oncologic outcome and long-term survival for patients with early gastric cancer after laparoscopic gastrectomy and open gastrectomy. In addition, the laparoscopic approach is associated with less severe morbidity and a lower occurrence of respiratory and wound-abdominal wall complications.

Five-year survival analysis of surgically resected gastric cancer cases in Japan: a retrospective analysis of more than 100,000 patients from the nationwide registry of the Japanese Gastric Cancer Association (2001-2007)

BACKGROUND

The aim of this retrospective study was to investigate the tumor characteristics, surgical details, and survival distribution of surgically resected cases of gastric cancer from the nationwide registry of the Japanese Gastric Cancer Association.

METHODS

Data from 118,367 patients with primary gastric carcinoma who underwent resection between 2001 and 2007 were included in the survival analyses. The 5-year survival rates were calculated for various subsets of prognostic factors.

RESULTS

The median age of the patients was 67 years. The proportions of patients with pathological stage (Japanese Gastric Cancer Association) IA, IB, II, IIIA, IIIB, and IV disease were 44.0%, 14.7%, 11.7%, 9.5%, 5.0%, and 12.4% respectively. The death rate within 30 days of operation was 0.5%. The 5-year overall survival rate in the 118,367 patients who were treated by resection was 71.1%. The 5-year overall survival rates of patients with pathological stage IA, IB, II, IIIA, IIIB, and IV disease were 91.5%, 83.6%, 70.6%, 53.6%, 34.8%, and 16.4% respectively. The 5-year disease-specific survival rates in the patients with pT1 (mucosa) disease after D1+ dissection of lymph node station no. 7 (D1 + α), D1+ dissection of lymph node station nos. 7, 8, and 9 (D1+ β), and D2 lymphadenectomy were 99.4%, 99.6%, and 99.1% respectively. The 5-year disease-specific survival rates in the patients with pT1 (submucosa) disease after D1 + α, D1 + β, and D2 lymphadenectomy were 97.3%, 98.1%, and 96.9% respectively.

CONCLUSION

Detailed analyses of the data from more than 100,000 patients show the recent trends of the outcomes of gastric cancer treatment in Japan and provide baseline information for use by medical communities around world.

Genetic host factors in Helicobacter pylori-induced carcinogenesis: Emerging new paradigms

Helicobacter Pylori is a gram negative rod shaped microaerophilic bacterium that colonizes the stomach of approximately half the world's population. Infection with c may cause chronic gastritis which via a quite well described process known as Correas cascade can progress through sequential development of atrophic gastritis, intestinal metaplasia and dysplasia to gastric cancer. H. pylori is currently the only bacterium that is classified as a class 1 carcinogen by the WHO, although the exact mechanisms by which this bacterium contributes to gastric carcinogenesis are still poorly understood. Only a minority of H. pylori-infected patients will eventually develop gastric cancer, suggesting that host factors may be important in determining the outcome of H. pylori infection. This is supported by a growing body of evidence suggesting that the host genetic background contributes to risk of H. pylori infection and gastric carcinogenesis. In particular single nucleotide polymorphisms in genes that influence bacterial handling via pattern recognition receptors appear to be involved, further strengthening the link between host risk factors, H. pylori incidence and cancer. Many of these genes influence cellular pathways leading to inflammatory signaling, inflammasome formation and autophagy. In this review we summarize known carcinogenic effects of H. pylori, and discuss recent findings that implicate host genetic pattern recognition pathways in the development of gastric cancer and their relation with H. pylori.

Is adjuvant chemotherapy necessary in pT1N1 gastric cancer?

Background

Due to a lack of consensus on adjuvant treatments for pT1N1 gastric cancer, surgeons face a dilemma when deciding treatments for patients with pT1N1 gastric cancer after gastrectomy. The objective of this study was to determine survival benefits of adjuvant chemotherapy and risk factors for tumor recurrence in gastric cancer patients with pT1N1.

Methods

Between 1996 and 2010, 510 patients who underwent curative resection for pT1N1 gastric cancer at three institutes were divided into two groups: adjuvant chemotherapy group (N = 150) and surgery-only group (N = 360). Disease-free survival rates and risk factors for tumor recurrence were analyzed.

Results

During the median follow-up of 78 months, 7.5% of patients experienced tumor recurrence (7.3% in adjuvant chemotherapy group and 7.5% in surgery-only group). The 5-year disease-free survival rate was 91.8% in the adjuvant chemotherapy group and 94.6% in the surgery-only group without significant difference between the two. In univariate analysis, older age (>65 years), male gender, body mass index <25 kg/m², elevated gross type, and differentiated histology were associated with tumor recurrence. Multivariate analysis showed that advanced age and male gender were independent risk factors for tumor recurrence. In addition, adjuvant chemotherapy showed no benefitial effect on tumor recurrence in pT1N1 gastric cancer.

Conclusions

Adjuvant chemotherapy did not show any oncologically benefitial effect on tumor recurrence, it might be unnecessary for pT1N1 gastric cancer after curative surgery.

Expanded endoscopic therapy criteria should be cautiously used in intramucosal gastric cancer

OBJECTIVE

Accurate estimation of lymph node metastasis (LNM) in intramucosal gastric cancer is essential to select less invasive treatment options and even avoid surgery. The aim of this study was to evaluate combined clinicopathological features to predict the presence of LNM.

METHODS

A retrospective review of data from 386 intramucosal gastric cancer patients who underwent gastrectomy with extended lymphadenectomy from 2003 to 2010 was conducted. The mutual relation between clinicopathological characteristics and LNM was analyzed.

RESULTS

LNM was detected in 40 (10.4%) of the 386 patients. Histological type and vascular or lymphatic invasion presence showed a positive correlation with LNM occurrence by univariate analysis. Multivariate analysis revealed that histological type was the only factor associated with LNM. Combined clinicopathologic characteristics would be more predictable for LNM. We found no LNM when we used combined clinicopathological characteristics conforming to Japanese absolute indications for endoscopic therapy. The LNM rate was as high as 8.7% when Japanese expanded criteria were used. Univariate analysis in cancer conformity to expand endoscopic submucosal dissection (ESD) indication also revealed that the undifferential type was the only significant factor for LNM.

CONCLUSIONS

It was possible to predict intramucosal gastric cancer cases without LNM using combined clinicopathological characteristic analysis. Extended indication for ESD should be cautiously used for intramucosal gastric cancer patients.

Review of atrophic gastritis and intestinal metaplasia as a premalignant lesion of gastric cancer

Atrophic gastritis (AG) and intestinal metaplasia (IM) are the main precursor lesions of gastric cancer as the incidence of gastric cancer increases in the gastric mucosa involved with AG and IM. The prevalence of AG and IM vary depending on countries, even it represents diverse results in the same nation. Usually AG is antecedent of IM but the etiologies of AG and IM are not always the same. The sensitivity and specificity of diagnostic methods to detect AG and IM are different. Furthermore, the management strategy of AG and IM has not been established, yet. Helicobacter pylori infection has been proved as the most important cause of AG and IM. Thus the eradication of H. pylori is very important to prevent the progression to gastric cancer which is still placed in the high rank in morbidity and mortality among cancers. However, the reversibility of AG and IM by eradication of H. pylori which was assumed to be certain by meta-analysis is; however, controversial now. Therefore, the understanding and early diagnosis of AG and IM are very important, especially, in high incidence area of gastric cancer such as Republic of Korea.

Prevalence and risk factors of atrophic gastritis and intestinal metaplasia: a nationwide multicenter prospective study in Korea

Background/Aims

Atrophic gastritis (AG) and intestinal metaplasia (IM) are premalignant gastric lesions. The aims of this study were to evaluate the prevalence of endoscopic AG and IM and to document the risk factors for these lesions.

Methods

In total, 4,023 subjects were enrolled at eight hospitals in Korea. AG and IM were diagnosed by endoscopy. Helicobacter pylori immunoglobulin G antibodies were measured.

Results

The prevalences of endoscopic AG and IM were 40.7% and 12.5%. In a multivariate analysis, the risk factors for AG were age groups of 40 to 59 years and >60 years, male sex, positive H. pylori serology, IM, and education below the college level (odds ratio [OR], 2.55, 5.00, 1.38, 1.41, 4.29, and 1.35, respectively). The risk factors for IM were age groups of 40 to 59 years and >60 years, male sex, positive H. pylori serology, AG, having relatives with gastric cancer, education below the college level and consumption of dairy products (OR, 3.16, 3.25, 1.88, 2.17, 3.68, 1.48, 1.47, and 1.40, respectively).

Conclusions

A nationwide survey regarding the prevalence of endoscopic AG and IM and their risk factors in Korea supports the hypothesis that endoscopic diagnosis of these premalignant lesions could be helpful to describe a group at high risk for gastric cancer.

GC-C gene silencing inhibits the growth of subcutaneously implanted gastric tumors in nude mice

AIM: To study the effect of GC-C gene silencing on the biological behaviors of subcutaneously implanted gastric tumors and to explore the possible mechanisms involved.

METHODS: Non-transfected SGC-7901 cells (SGC-7901 group), SGC-7901 cells transfected cell with an empty plasmid (PRNA group), and those transfected with a shRNA targeting the GC-C gene (GC-C-shRNA group) were subcutaneously inoculated into nude mice. Then, the histologically intact xenograft tissues were subcutaneously transplanted to nude mice to observe the condition of nude mice and determine the rate of tumor survival and growth velocity. The levels of GC-C mRNA and protein were determined by RFQ-PCR and Western blot, respectively. The heteromorphism and necrosis of tumor cells were observed after HE staining. The expression of CXCR4 protein was detected by Western blot and immunohistochemistry.

RESULTS: The rate of tumor survival and the condition of nude mice did not differ significantly among the three groups. Compared to the SGC-7901 group and PRNA group, the tumors grew more slowly and became smaller in the GC-C-shRNA group (all P < 0.05). The reduced rate of tumor growth velocity and volume in the GC-C-shRNA group were 33.7% and 33.2%, respectively, and GC-C gene silencing efficiency was 66.8% and 64.4%, respectively (P < 0.05). The expression of GC-C protein decreased by 50.0% and 49.6%, respectively (P < 0.05), and the degree of tumor heteromorphism and necrosis and expression of CXCR4 protein in the GC-C-shRNA group decreased obviously (all P < 0.05).

CONCLUSION: GC-C gene silencing slows the growth velocity of gastric tumors in vivo possibly in a CXCR4-dependent manner.

Ectopic expression of guanylyl cyclase C and endogenous ligand guanylin correlates significantly with Helicobacter pylori infection in gastric carcinogenesis

The molecular mechanisms leading to gastric carcinogenesis still remain unclear. Recently, several studies demonstrated that over-expression of guanylyl cyclase C (GCC) has been detected in intestinal-type gastric cancer (GC) and precursor lesions. Our objective was to explore the expression levels of GCC and endogenous ligands guanylin (GN) and uroguanylin (UGN) and the correlation between Helicobacter pylori (H. pylori) and GCC, GN, and UGN expressions in patients at different stages from normal mucosa to superficial gastritis, atrophic gastritis, intestinal metaplasia (IM), dysplasia, and finally adenocarcinoma. The expression of GCC and GN was absent in the distal normal gastric tissues and superficial gastritis in all cases, whereas they were measured in IM, dysplasia, and GC. The expression of GCC and GN was closely related to intestinal-type GC. From superficial gastritis to gastric carcinomas, the H. pylori positive rate was 19.7, 33.3, 69.6, 80.0, and 82.1%, respectively. The positive correlation was found between GCC and GN in IM, dysplasia, and GC. Also, the positive correlation was found between GCC, GN, and H. pylori infection in them. These results demonstrate that the detection of GCC and GN will be beneficial to diagnosis human gastric carcinoma and precancerous lesions. Ectopic expression of GCC and GN in human gastric mucosa and H. pylori infection may play an important role in the carcinogenesis of the intestinal-type GC.

Sentinel lymph node biopsy to direct treatment in gastric cancer. A systematic review of the literature

Gastric cancer is one of the main causes of cancer-related deaths around the world. The prevalence of early gastric cancer (EGC) among all gastric cancers of 45-51% in Japan, but only 7-28% in Western countries. The prevalence of EGC is growing partly because of better diagnostics and screening programmes. Possible treatment options for EGC treatment are expanded by the introduction of endoscopic mucosal resection and endoscopic submucosal dissection Therefore, detailed knowledge about nodal metastatic risk is warranted. We performed a systematic review of the literature concerning studies investigating the role of sentinel lymph node biopsy in EGCr and whether there is enough proof to introduce SLN as a part of treatment for EGC in the Netherlands. Several detection substances (dye or radiocolloid) and injection methods (submucosal or subserosal) are investigated. An overall sensitivity percentage of 85.4% was found. In comparison, high and clinically sufficient percentages were observed for specificity (98.2%), negative predictive value (90.7%) and accuracy (94%). Subgroup analyses showed that the combination of dye and radiocolloid detection substances is the best method for sentinel lymph node detection in early gastric cancer. However, the precise method of sentinel lymph node biopsy in EGC has to be determined further. Large, randomized series should be initiated in Europe to address this issue.

Recurrence after curative resection of early gastric cancer

BACKGROUND

Few studies have evaluated the recurrence of EGC after curative gastrectomy, due to its relatively low incidence. This study evaluated recurrence patterns and independent predictive factors for recurrence in order to determine appropriate follow-up and early detection of recurrence.

METHODS

We reviewed the medical records of 3,883 consecutive patients who underwent curative gastrectomy for EGC at Samsung Medical Center between February 1995 and January 2006 and were followed up until January 2008. The clinical and pathological characteristics and the predictive factors for recurrence were evaluated retrospectively.

RESULTS

Eighty-five (2.2%) patients had recurrence, and liver was the most common site of recurrence (45.9%). The recurrence rates within 2, 3, and 5 years were 43.5%, 67.1%, and 85.6%, respectively. There were 106 overall recurrences, with 86 (81.1%) being detected by computed tomography (CT). Second primary cancer was the primary cause of death after gastrectomy, followed by recurrence. Old age (>60 years), tumor size (>3 cm), multiple tumor, N category, and N2 station metastasis were significant factors for recurrence by multivariate analysis, but depth of invasion was not a significant factor.

CONCLUSIONS

Age, tumor size, number of tumors, N category, and N2 station metastasis were predictive factors for recurrence, with lymph node metastasis being the most significant factor. After curative gastrectomy, follow-up programs should be applied for more than 5 years for EGC patients, and computed tomography could be an essential diagnostic tool.

Lymph node metastasis in submucosal gastric cancer and reduction surgery

Although the concept of early gastric cancer (EGC) has been accepted, lymph node metastasis is the most important prognostic factor for EGC. Submucosal gastric cancer is greatly concerned because of its high lymph node metastasis incidence accounting for about 20% of all lymph node metastases. Many researchers suggest that reduction surgery should be performed for submucosal gastric cancer patients at a lower risk of developing lymph node metastasis. Submucosal gastric cancer can be divided into 3 levels (Sm1, Sm2, Sm3) based on its depth of invasion, which has been proven useful for predicting lymph node metastasis, directing treatment and evaluating prognosis. Recently, with the advances in clinical pathology and molecular biology, the risk factor for lymph node metastasis of submucosal gastric cancer can be accurately evaluated and its treatment has become rather rational. This paper reviews the relative factors for lymph node metastasis of submucosal gastric cancer and advances in its rational surgical treatment.

Outcome of gastric cancer patients after successful gastrectomy: influence of the type of recurrence and histology on survival

BACKGROUND

The effect of the location of disease recurrence after curative (R0) gastrectomy on patient survival has not been elucidated. The authors hypothesized that the location of recurrence would have a significant influence on survival.

METHODS

Medical records of all patients who received treatment for gastric cancer at The University of Texas M. D. Anderson Cancer Center between 1985 and 1998 were reviewed. Patients who underwent R0 resection for gastric cancer and subsequently developed localized (anastomotic) recurrence (LR), lymph node (regional) recurrence (NR), or distant metastases (DM) were analyzed for overall survival (OS). All study factors were entered into a Cox proportional hazards model to provide multivariate hazard ratios. The model was adjusted for the effects of primary site of recurrence, histologic grade, patient age, and location of the primary tumor.

RESULTS

This retrospective analysis included 227 consecutive patients. The median survival of patients who developed NR (11 months) was similar to that of patients who developed LR (10 months), but both groups had significantly longer median survival compared with patients who developed DM (7 months; log-rank P = .03). Patients who had well differentiated or moderately differentiated tumors had a longer OS (11 months) than patients who had poorly differentiated tumors (8 months; log-rank P = .02). In this cohort, location of the primary cancer and age at recurrence had no significant impact on OS.

CONCLUSIONS

The data from this study suggested that, among patients who undergo R0 gastrectomy for gastric cancer, LR and NR versus DM should be considered a valid stratification factor for randomized trials based on significant differences in survival. Determining whether this stratification should apply to histologic differentiation will require further investigation in a larger multicenter cohort.