Effect of Laparoscopic Distal Gastrectomy vs Open Distal Gastrectomy on Long-term Survival Among Patients With Stage I Gastric Cancer: The KLASS-01 Randomized Clinical Trial

Survival outcomes after laparoscopy-assisted distal gastrectomy versus open distal gastrectomy with nodal dissection for clinical stage IA or IB gastric cancer (JCOG0912): a multicentre, non-inferiority, phase 3 randomised controlled trial

BACKGROUND

Laparoscopy-assisted distal gastrectomy (LADG) is increasingly being used as an alternative to open distal gastrectomy (ODG) for gastric cancer treatment. Retrospective studies have shown equivalent survival with the two procedures, but these studies are limited by selection bias because LADG is more technically difficult than ODG. We aimed to evaluate whether LADG was non-inferior to ODG in terms of long-term survival outcomes.

METHODS

We did an open-label, multicentre, non-inferiority, phase 3 randomised controlled trial at 33 institutions in Japan. Patients aged 20-80 years with histologically confirmed gastric adenocarcinoma (T1N0, T1N1, or T2[MP]N0), clinical stage I, in the middle or lower third of the stomach, Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, with a body-mass index of less than 30 kg/m², were randomly assigned (1:1) to receive ODG or LADG. Randomisation was done by telephone, fax, or with a web-based system in the Japan Clinical Oncology Group Data Center; a minimisation method with a random component was used to adjust for institution and clinical stage (IA or IB). Only study-accredited surgeons performed ODG and LADG. The primary endpoint was relapse-free survival and was analysed according to the intention-to-treat principle. The non-inferiority margin (LADG vs ODG) was set at a hazard ratio (HR) of 1·54. The trial was registered with the UMIN Clinical Trials Registry, UMIN000003319.

FINDINGS

Between March 15, 2010, and Nov 29, 2013, 921 patients were enrolled and randomly assigned to receive ODG (n=459) or LADG (n=462). 912 (99%) participants had the assigned surgery. 5-year relapse-free survival was 94·0% (95% CI 91·4-95·9) in the ODG group and 95·1% (92·7-96·8) in the LADG group. LADG was non-inferior to ODG for relapse-free survival (HR 0·84 [90% CI 0·56-1·27]), p=0·0075). The most common grade 3 or 4 adverse event was bowel obstruction, occurring in 11 (2%) of 455 patients in the ODG group and five (1%) of 457 patients in the LADG group. There were no treatment-related deaths.

INTERPRETATION

This trial supports the non-inferiority of LADG compared with ODG for clinical stage I gastric cancer relapse-free survival, suggesting that LADG should be considered a standard treatment option when performed by experienced surgeons.

FUNDING

Japan National Cancer Center, Ministry of Health, Labour and Welfare of Japan, Japan Agency for Medical Research and Development.

Clinical Implications of Microsatellite Instability in Early Gastric Cancer

Purpose

We aimed to evaluate the clinical characteristics of microsatellite instability in early gastric cancer.

Materials and Methods

The microsatellite instability status of resected early gastric tumors was evaluated using two mononucleotide repeat markers (BAT25 and BAT26) and three dinucleotide repeat markers (D5S346, D2S123, and D17S250). Tumors with instability in two or more markers were defined as microsatellite instability-high (MSI-H) and others were classified as microsatellite stable (MSS).

Results

Overall, 1,156 tumors were included in the analysis, with 85 (7.4%) classified as MSI-H compared with MSS tumors. For MSI-H tumors, there was a significant correlation with the female sex, older age, tumor location in the lower gastric body, intestinal histology, lymphovascular invasion (LVI), and submucosal invasion (P<0.05). There was also a trend toward an association with lymph node (LN) metastasis (P=0.056). In mucosal gastric cancer, there was no significant difference in MSI status in tumors with LN metastasis or tumors with LVI. In submucosal gastric cancer, LVI was more frequently observed in MSI-H than in MSS tumors (38.9% vs. 25.0%, P=0.027), but there was no difference in the presence of LN metastases. The prognosis of MSI-H tumors was similar to that of MSS tumors (log-rank test, P=0.797, the hazard ratio for MSI-H was adjusted by age, sex, pT stage, and the number of metastatic LNs, 0.932; 95% confidence interval, 0.423–2.054; P=0.861).

Conclusions

MSI status was not useful in predicting prognosis in early gastric cancer. However, the frequent presence of LVI in early MSI-H gastric cancer may help guide the appropriate treatment for patients, such as endoscopic treatment or limited LN surgical dissection.

Advances in the treatment of gastric cancer: 2019

PURPOSE OF REVIEW

The aim of this study was to review studies published within the past year regarding management of gastric cancer.

RECENT FINDINGS

Laparoscopic gastrectomy achieves equivalent survival compared with open gastrectomy in early stage and locally advanced gastric cancer. Adjuvant chemotherapy with 6 months of S-1 and oxaliplatin was superior to 12 months of S-1, and the addition of postoperative radiation therapy did not improve survival. The FLOT regimen is the new standard for preoperative chemotherapy. In metastatic gastric cancer, the addition of docetaxel to S-1 and cisplatin failed to improve overall survival over two-drug chemotherapy. The addition of the immune checkpoint inhibitor pembrolizumab to chemotherapy failed to improve overall survival compared with chemotherapy alone.

SUMMARY

Laparoscopic gastrectomy is acceptable in early and locally advanced gastric cancer. Combination adjuvant chemotherapy is superior to S-1 monotherapy. Adjuvant radiation therapy after D2 gastrectomy for node-positive gastric cancer does not improve survival. Preoperative chemotherapy with FLOT (5-FU, leucovorin, oxaliplatin and docetaxel) without radiation therapy is the standard treatment in the West. Two-drug chemotherapy is the optimal initial treatment in metastatic disease. Adding pembrolizumab to front-line chemotherapy did not improve survival, with use of immune checkpoint inhibitors reserved to treat chemotherapy refractory metastatic disease.

Biomarkers for Evaluating the Inflammation Status in Patients with Cancer

Inflammation can be a causative factor for carcinogenesis or can result from a consequence of cancer progression. Moreover, cancer therapeutic interventions can also induce an inflammatory response. Various inflammatory parameters are used to assess the inflammatory status during cancer treatment. It is important to select the most optimal biomarker among these parameters. Additionally, suitable biomarkers must be examined if there are no known parameters. We briefly reviewed the published literature for the use of inflammatory parameters in the treatment of patients with cancer. Most studies on inflammation evaluated the correlation between host characteristics, effect of interventions, and clinical outcomes. Additionally, the levels of C-reactive protein, albumin, lymphocytes, and platelets were the most commonly used laboratory parameters, either independently or in combination with other laboratory parameters and clinical characteristics. Furthermore, the immune parameters are classically examined using flow cytometry, immunohistochemical staining, and enzyme-linked immunosorbent assay techniques. However, gene expression profiling can aid in assessing the overall peri-interventional immune status. The checklists of guidelines, such as STAndards for Reporting of Diagnostic accuracy and REporting recommendations for tumor MARKer prognostic studies should be considered when designing studies to investigate the inflammatory parameters. Finally, the data should be interpreted after adjusting for clinically important variables, such as age and cancer stage.

Prognosis After Laparoscopic Gastrectomy in Patients with Pathological Stage II or III Gastric Cancer Who Were Preoperatively Diagnosed with Clinical Stage I: Propensity Score Matching Analysis of a Multicenter Dataset

BACKGROUND

Laparoscopic gastrectomy (LG) is a standard approach for patients with clinical stage I gastric cancer in East Asia; however, following surgery, these patients may be pathologically diagnosed with stage II or III cancer. The prognosis of patients with gastric cancer migration from clinical stage I to pathological stage II or III after LG has not been completely clarified.

METHODS

To compare the prognosis following LG and open gastrectomy (OG) in patients with pathological stage II or III gastric cancer who were preoperatively diagnosed with stage I cancer, we conducted a retrospective analysis using a multicenter dataset comprising details of 3480 patients who underwent gastrectomy between 2010 and 2014 at nine participating institutions. We used propensity score matching to reduce selection bias.

RESULTS

After propensity score matching, 146 patients were finally selected. There were no significant differences in the number of dissected lymph nodes. Morbidity rates, length of postoperative hospital stay, and time between surgery and initiation of adjuvant chemotherapy were comparable between the two groups. Moreover, there were no significant differences in the overall, disease-specific, and relapse-free survival rates between the LG and OG groups. The LG group tended to have more patients with hematogenous recurrence, whereas the OG group tended to have more patients with peritoneal recurrence.

CONCLUSIONS

Our multicenter dataset analysis indicated that the prognosis of patients with gastric cancer migration from clinical stage I to pathological stage II or III was independent of the surgical approach.

Oncological feasibility of laparoscopic subtotal gastrectomy compared with laparoscopic proximal or total gastrectomy for cT1N0M0 gastric cancer in the upper gastric body

BACKGROUND

The upper gastric body is of particular interest in relation to gastrectomy because this area includes a border; that is, both distal and proximal gastrectomy for early gastric cancer can involve this area. Laparoscopic subtotal gastrectomy (LsTG) is reported to be suitable procedure compared with laparoscopic proximal and total gastrectomy (LPG, LTG), regarding postoperative nutritional status and surgical safety. However, whether LsTG is an oncologically acceptable procedure for early gastric cancer in the upper gastric body is unclear.

METHODS

We analyzed 215 patients with cT1N0M0 gastric cancer limitedly located in the upper gastric body. The frequency of conversion from each intended procedure to an alternative procedure, the width of the pathological margin, the incidence of lymph node metastasis at each station and the 3-year overall survival (OS) and relapse-free survival (RFS) were evaluated.

RESULTS

LsTG was planned for 65 patients, and LPG for 72 and LTG for 78, respectively. Conversion to other procedures was required in about 10% of patients for whom LsTG or LPG was planned. The width of the pathological margin in patients who underwent LsTG was significantly shorter than patients who underwent the others. No patients who underwent LsTG, LPG or LTG had metastases in station no. 2 or 4sa lymph node. The 3-year OS and RFS rates of patients for whom each procedure was planned were not different.

CONCLUSIONS

LsTG could be an oncologically acceptable procedure for cT1N0M0 gastric cancer in the upper gastric body. LsTG could be one option for such disease.

Short-Term Outcomes of Laparoscopic and Open Total Gastrectomy for Gastric Cancer: A Nationwide Retrospective Cohort Analysis

BACKGROUND

Laparoscopic total gastrectomy is gradually gaining popularity; however, previous studies have produced conflicting results regarding the safety and advantages of the procedure, partly because of small sample sizes. The purpose of this study was to compare short-term outcomes between laparoscopic and open total gastrectomy for gastric cancer.

METHODS

We analyzed data for patients undergoing laparoscopic or open total gastrectomy for clinical stage I-III gastric cancer from July 2010 to March 2017, using a Japanese nationwide inpatient database. We performed propensity-matched analyses to compare in-hospital mortality, morbidity, duration of anesthesia, time to first oral intake, and length of postoperative stay between the two groups.

RESULTS

Among 58,689 eligible patients, propensity-score matching created 12,229 pairs. Laparoscopic total gastrectomy was associated with higher incidences of anastomotic leakage (2.9% vs. 1.7%, p < 0.001) and stenosis (0.9% vs. 0.6%, p = 0.02), lower incidences of pancreatic injury (1.4% vs. 1.8%, p = 0.01), endoscopic hemostasis (0.9% vs. 1.7%, p < 0.001), blood transfusion (9.9% vs. 17.7%, p < 0.001) and 30-day readmission, a shorter interval from surgery to first oral intake (4 vs. 5 days, p < 0.001), shorter postoperative hospital stay (14 vs. 15 days, p < 0.001), and a longer duration of anesthesia (323 vs. 304 min, p < 0.001). There was no significant difference in in-hospital mortality (0.6% vs. 0.8%, p = 0.58).

CONCLUSIONS

Laparoscopic total gastrectomy has some advantages over open surgery for gastric cancer in terms of time to first oral intake and postoperative length of stay, but the incidence of anastomotic leakage was higher than that of open total gastrectomy.

Multi-institutional analysis of the prognostic significance of postoperative complications after curative resection for gastric cancer

Background

Insufficient data are available on the prognostic significance of complications after resection of gastric cancer. Therefore, we aimed to assess this gap in our knowledge by studying patients with resectable gastric cancer.

Methods

A multi‐institutional retrospective database comprising clinical information of 3575 patients who received resection of gastric cancer from 2010 to 2014 at nine institutions. Grades 2 or greater complications of the Clavien‐Dindo classification were judged as clinically relevant postoperative complications, and their associations with postoperative survival were assessed. We assessed the effect of complications on times of initiation and continuation of postoperative adjuvant chemotherapy by S‐1.

Results

A total of 2954 patients were included in the analysis. Clinically relevant postoperative complications occurred in 664 (23%) patients. Patients’ recurrence‐free survival rate incrementally decreased as the grade of complications became greater. Patients with abdominal complications (eg, leakage of pancreatic fluids, intra‐abdominal abscess, and anastomotic leakage) and those with nonabdominal complications (eg, pneumonia) experienced worse recurrence‐free survival compared to those without complications. Patients who had complications were generally at greater risk of disease recurrence, except for those who underwent laparoscopic surgery and those with pathological stage I. Delayed initiation and shorter continuation of adjuvant S‐1 chemotherapy was experienced by patients with postoperative complications.

Conclusions

Postoperative complications adversely affected the prognosis in patients with resectable gastric cancer.

Effect of Laparoscopic vs Open Distal Gastrectomy on 3-Year Disease-Free Survival in Patients With Locally Advanced Gastric Cancer: The CLASS-01 Randomized Clinical Trial

IMPORTANCE

Laparoscopic distal gastrectomy is accepted as a more effective approach to conventional open distal gastrectomy for early-stage gastric cancer. However, efficacy for locally advanced gastric cancer remains uncertain.

OBJECTIVE

To compare 3-year disease-free survival for patients with locally advanced gastric cancer after laparoscopic distal gastrectomy or open distal gastrectomy.

DESIGN, SETTING, AND PATIENTS

The study was a noninferiority, open-label, randomized clinical trial at 14 centers in China. A total of 1056 eligible patients with clinical stage T2, T3, or T4a gastric cancer without bulky nodes or distant metastases were enrolled from September 2012 to December 2014. Final follow-up was on December 31, 2017.

INTERVENTIONS

Participants were randomized in a 1:1 ratio after stratification by site, age, cancer stage, and histology to undergo either laparoscopic distal gastrectomy (n = 528) or open distal gastrectomy (n = 528) with D2 lymphadenectomy.

MAIN OUTCOMES AND MEASURES

The primary end point was 3-year disease-free survival with a noninferiority margin of -10% to compare laparoscopic distal gastrectomy with open distal gastrectomy. Secondary end points of 3-year overall survival and recurrence patterns were tested for superiority.

RESULTS

Among 1056 patients, 1039 (98.4%; mean age, 56.2 years; 313 [30.1%] women) had surgery (laparoscopic distal gastrectomy [n=519] vs open distal gastrectomy [n=520]), and 999 (94.6%) completed the study. Three-year disease-free survival rate was 76.5% in the laparoscopic distal gastrectomy group and 77.8% in the open distal gastrectomy group, absolute difference of -1.3% and a 1-sided 97.5% CI of -6.5% to ∞, not crossing the prespecified noninferiority margin. Three-year overall survival rate (laparoscopic distal gastrectomy vs open distal gastrectomy: 83.1% vs 85.2%; adjusted hazard ratio, 1.19; 95% CI, 0.87 to 1.64; P = .28) and cumulative incidence of recurrence over the 3-year period (laparoscopic distal gastrectomy vs open distal gastrectomy: 18.8% vs 16.5%; subhazard ratio, 1.15; 95% CI, 0.86 to 1.54; P = .35) did not significantly differ between laparoscopic distal gastrectomy and open distal gastrectomy groups.

CONCLUSIONS AND RELEVANCE

Among patients with a preoperative clinical stage indicating locally advanced gastric cancer, laparoscopic distal gastrectomy, compared with open distal gastrectomy, did not result in inferior disease-free survival at 3 years.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01609309.

History of Esophagogastric Junction Cancer Treatment and Current Surgical Management in Western Countries

The incidence of esophagogastric junction (EGJ) cancer has been significantly increasing in Western countries. Appropriate planning for surgical therapy requires a reliable classification of EGJ cancers with respect to their exact location. Clinically, the most accepted classification of EGJ cancers is "adenocarcinoma of the EGJ" (AEG or "Siewert"), which divides tumor center localization into AEG type I (distal esophagus), AEG type II ("true junction"), and AEG type III (subcardial stomach). Treatment strategies in western countries routinely employ perioperative chemotherapy or neoadjuvant chemoradiation for cases of locally advanced cancers. The standard surgical treatment strategies are esophagectomy for AEG type I and gastrectomy for AEG type III cancers. For "true junctional cancers," i.e., AEG type II, whether the extension of resection in the oral or aboral direction represents the most effective surgical therapy remains debatable. This article reviews the history of surgical EGJ cancer treatment and current surgical strategies from a Western perspective.