Evaluation of the recurrence pattern of gastric cancer after laparoscopic gastrectomy with D2 lymphadenectomy

Helicobacter pylori modulated host immunity in gastric cancer patients with S-1 adjuvant chemotherapy

BACKGROUND

Paradoxically, Helicobacter pylori-positive (HP+) advanced gastric cancer patients have a better prognosis than those who are HP-negative (HP-). Immunologic and statistical analyses can be used to verify whether systemic mechanisms modulated by HP are involved in this more favorable outcome.

METHODS

A total of 658 advanced gastric cancer patients who underwent gastrectomy were enrolled. HP infection, mismatch repair, programmed death-ligand 1 (PD-L1), and CD4/CD8 proteins, and microsatellite instability were analyzed. Overall survival (OS) and relapse free survival (RFS) rates were analyzed after stratifying clinicopathological factors. Cox proportional hazards regression analysis was performed to identify independent prognostic factors.

RESULTS

Among 491 cases that were analyzed, 175 (36%) and 316 (64%) cases were HP+ and HP⁻, respectively. Analysis of RFS indicated an interaction of HP status among the subgroups for S-1 dose (Pinteraction=0.0487) and PD-L1 (P = .016). HP+ patients in the PD-L1⁻ group had significantly higher five-year OS and RFS than HP- patients (81% vs. 68%; P = .0011; HR 0.477; 95% CI, 0.303-0.751 and 76% vs. 63% P = .0011; HR 0.508; 95% CI, 0.335-0.771, respectively). The five-year OS and RFS was also significantly higher for HP+ compared to HP- patients in the PD-L1-/S-1-reduced group (86% vs. 46%; P = .0014; HR 0.205; 95% CI, 0.07-0.602 and 83% vs. 34%; P = .001; HR 0.190; 95% CI, 0.072-0.498, respectively). Thus, HP status was identified as one of the most potentially important independent factors to predict prolonged survival.

CONCLUSION

This retrospective study suggests that an HP-modulated host immune system may contribute to prolonged survival in the absence of immune escape mechanisms of gastric cancer.

A Case Study on Modeling the Time to Recurrence of Gastric Cancer Patients

BACKGROUND

Gastric cancer is a malignant tumor of the stomach and it is one of the leading causes of death worldwide. The study aimed to model the time to first recurrence of gastric cancer patients at the Tikur Anbesa specialized hospital.

METHODS

The data for this study were gastric cancer patients followed up from January 1, 2013 to February 29, 2020 at Tikur Anbesa Specialized Hospital, Oncology Center, Addis Ababa. We used Weibull, log-logistic and lognormal as baseline hazard functions with the gamma and the inverse Gaussian frailty distributions. Data analyzed with the statistical software R.

RESULTS

The median recurrence time of the patients was about 23.96 months with a maximum recurrence time of 60.81 months, of which about 61.2% had first recurrences of gastric cancer. The clustering effect is significant in modeling the time to recurrence of gastric cancer. According to the result of the log-logistic inverse Gaussian frailty model, the sex of the patient, the tumor size, smoking habit, the treatment carried out, the vascular invasion, the stage of the disease, the helicobacter pylori infection and the histological type were the significant prognostic factors  at 5% level of significance.

CONCLUSION

Inverse Gaussian frailty model is the model that best describes the time to recurrence of the gastric cancer data set. Gender of the patients, tumor size, treatment taken, vascular invasion, disease stage, helicobacter pylori infection and histological type were the determining prognostic factors. This requires measures to improve patient health and prevent relapse based on significant risk factors, and particular attention should be paid to patients with such factors.

Outcomes of preoperative S-1 and docetaxel combination chemotherapy in patients with locally advanced gastric cancer

PURPOSE

The therapeutic outcomes of stage III gastric cancer patient receiving D2 gastrectomy and adjuvant chemotherapy remain unsatisfactory. To improve the long-term outcomes in this population, the combination of docetaxel and S-1 (DS) therapy can be expected to be a useful regimen as neoadjuvant chemotherapy (NAC). This study aimed to prospectively evaluate the efficacy of NAC-DS for clinical stage III gastric cancer.

METHODS

Between January 2010 and December 2013, 26 patients were enrolled. Patients with clinical stage III gastric cancer received two courses of docetaxel 40 mg/m² on day 1, 15 and S-1 40 mg/m² bid orally on day 1-7, 15-21 every 4 weeks, followed by radical D2 gastrectomy. Short- and long-term outcomes were evaluated. This study was approved by the ethics committee of Yokohama City University, and was registered in the University Hospital Medical Information Network (UMIN) database (ID: 000011521).

RESULTS

Of 26 patients, 24 (92.3%) patients completed two courses of NAC. After NAC-DS, Grade 3 neutropenia was observed in 5 (19.2%) patients including one patient with febrile neutropenia, anemia in 1 (3.8%) patient and diarrhea in 1 (3.8%) patient. All patients underwent R0 gastrectomy and pathological response was found in 15 (57.6%) patients. Postoperatively, Clavien-Dindo grade II complication occurred in 8 (30.7%) patients and no mortality was observed. The 5-year overall survival (OS) was 57.7%, median OS was 78.7 months and recurrence free survival (RFS) was 49.0%, median RFS was 45.4 months with 66.5 months median follow-up. Pathological response (HR = 0.091, 95% CI 0.011-0.730, p = 0.016) and > 5% body weight loss before NAC-DS (HR = 0.133, 95% CI 0.023-0.765, p = 0.024) were independent risk factors for recurrence, > 5% body weight loss before NAC-DS (HR = 0.133, 95% CI 0.023-0.765, p = 0.024) were independent risk factors for overall survival by multivariate analysis.

CONCLUSIONS

NAC-DS demonstrated acceptable toxicity with a high R0 resection rate in clinical stage III gastric cancer patients, especially in patients with good nutritional status. Further prospective study is warranted to compare the long-term outcomes between with and without NAC-DS.

A Proposal of a Personalized Surveillance Strategy for Gastric Cancer: A Retrospective Analysis of 9191 Patients

Background

In gastric cancer, various surveillance strategies are suggested in international guidelines. The current study is intended to evaluate the current strategies and provide more personalized proposals for personalized cancer medicine.

Materials and Methods

In the aggregate, 9191 patients with gastric cancer after gastrectomy from 1998 to 2009 were selected from the Surveillance, Epidemiology, and End Results database. Disease-specific survival was analyzed by Kaplan-Meier method and the log-rank test. Cox proportional hazards regression analyses were used to confirm the independent prognostic factors. As well, hazard ratio (HR) curves were used to compare the risk of death over time. Conditional survival (CS) was applied to dynamically assess the prognosis after each follow-up.

Results

Comparisons from HR curves on different stages showed that earlier stages had distinctly lower HR than advanced stages. The curve of stage IIA was flat and more likely the same as that of stage I while that of stage IIB is like that of stage III with an obvious peak. After estimating CS at intervals of three months, six months, and 12 months in different periods, stages I and IIA had high levels of CS all along, while there were visible differences among CS levels of stages IIB and III.

Conclusions

The frequency of follow-up for early stages, like stages I and IIA, could be every six months or longer in the first three years and annually thereafter. And those with unfavorable conditions, such as stages IIB and III, could be followed up much more frequently and sufficiently than usual.

Peritoneal recurrence in gastric cancer following curative resection can be predicted by postoperative but not preoperative biomarkers: a single-institution study of 320 cases

To determine the risk factors for peritoneal recurrence in gastric cancer patients after curative resection, we included 320 patients with stage I-III primary gastric cancer between January 2008 and June 2012. Data on each patient's surgical and pathological information, preoperative and postoperative tumor markers were collected and analyzed retrospectively. The risk factors for peritoneal recurrence were investigated by univariate and multivariate analysis. In patients with peritoneal recurrence, advanced T or N stage, low differentiation, vascular/lymphatic invasion, perineural invasion, and elevated postoperative CEA/CA19-9 were more common than in patients without peritoneal recurrence. Patients with peritoneal recurrence showed a worse overall survival (OS) compared to those without peritoneal recurrence. In addition, patients with peritoneal recurrence within the first year had a worse OS compared to those with recurrence after 1 year. The univariate and multivariate analyses revealed that elevated number of metastatic lymph nodes and elevated postoperative CEA and CA19-9 were three independent risk factors for peritoneal recurrence in gastric cancer patients. For patients with N3 stage and high postoperative CEA and CA19-9, we found an initial steep slope within approximately 1 year and a subsequent gentle slope in the risk curve. Combined receiver operating characteristic curve analysis using the three independent risk factors for peritoneal recurrence yielded an area under the curve value of 0.73 with 73.7% sensitivity and 64.2% specificity. Therefore, the risk factors may be associated with peritoneal recurrence after curative resection in selected gastric cancer patients.

Early postoperative imaging after non-bariatric gastric resection: a primer for radiologists

Abstract

Surgical resection represents the mainstay treatment and only potentially curative option for gastric carcinoma, and is increasingly performed laparoscopically. Furthermore, other tumours and selected cases of non-malignant disorders of the stomach may require partial or total gastrectomy. Often performed in elderly patients, gastric resection remains a challenging procedure, with significant morbidity (14–43% complication rate) and non-negligible postoperative mortality (approximately 3%). This paper provides an overview of contemporary surgical techniques for non-bariatric gastric resection, reviews and illustrates the expected postoperative imaging appearances, common and unusual complications after partial and total gastrectomy. Albeit cumbersome or unfeasible in severely ill or uncooperative patients, contrast fluoroscopy remains useful to rapidly check for anastomotic patency and integrity. Currently, emphasis is placed on multidetector CT, which comprehensively visualizes the surgically altered anatomy and consistently detects complications such as anastomotic leaks and fistulas, duodenal stump leakage, afferent loop syndrome, haemorrhages, pancreatic fistulas and porto-mesenteric venous thrombosis. Our aim is to help radiologists become familiar with early postoperative imaging, in order to understand the surgically altered anatomy and to differentiate between expected imaging appearances and abnormal changes heralding iatrogenic complications, thus providing a consistent basis for correct choice between conservative, interventional or surgical treatment.

Teaching points

• Radical gastrectomy is associated with frequent postoperative morbidity and non-negligible mortality.

• In cooperative patients fluoroscopy allows checking for anastomotic patency and leaks.

• Multidetector CT with / without oral contrast comprehensively visualizes the operated abdomen.

• Awareness of surgically altered anatomy and expected postoperative appearances is warranted.

• Main complications include anastomotic and duodenal leaks, haemorrhages and pancreatic fistulas.