Jen Hao Chen

Initial Experience of Robotic Gastrectomy and Comparison with Open and Laparoscopic Gastrectomy for Gastric Cancer

BackgroundRobotic gastrectomy has become more popular in the treatment of gastric cancer, especially in Asian countries. Until now, few studies have compared robotic surgery with open or laparoscopic surgery for gastric cancer patients.MethodsData were prospectively collected between January 2006 and February 2012. A total of 689 patients underwent curative resection of adenocarcinoma of the stomach. Patients were separated into three groups according to the different surgical approaches used (586 open, 64 laparoscopic, and 39 robotic). The clinicopathological characteristics and surgical outcomes of the three groups were compared.ResultsThe open group was associated with a larger tumor size, more D2 dissection, more advanced tumor stage, and more blood loss than the groups treated with laparoscopic and robotic methods. Robotic gastrectomy was associated with female predominance, less blood loss, shorter hospital stay, and longer operative time than open and laparoscopic gastrectomy. The retrieved lymph node numbers were similar between the open and robotic groups. Postoperative morbidity rates were similar among the three groups. In terms of the learning curve of robotic gastrectomy, operative time and docking time were significantly reduced in the recent robotic group (nu2009=u200914) compared to the initial robotic group (nu2009=u200925).ConclusionRobotic gastrectomy could achieve extended lymph node dissection similar to open surgery. Our results showed a significant learning curve effect in the initial 25 cases of the robotic group.

Quality of life after curative gastrectomy for gastric cancer in a randomised controlled trial

Quality of life (QOL) was studied in gastric cancer patients treated on a randomised, controlled trial comparing D1 (level 1) with D3 (levels 1, 2 and 3) lymphadenectomy. A total of 221 patients were randomly assigned to D1 (n=110) and D3 (n=111) surgery. Quality-of-life assessments included functional outcomes (a 14-item survey about treatment-specific symptoms) and health perception (Spitzer QOL Index) was performed before and after surgery at disease-free status. Patients suffered from irrelative events such as loss of partners was excluded thereafter. Main analyses were done by intention-to-treat. Thus, 214 D1 (106/110=96.4%) and D3 (108/111=97.3%) R0 patients were assessed. Longitudinal analysis showed that functional outcomes decreased at 6 months after surgery and increased over time thereafter, while health perceptions increased over time in general. On the basis of linear mixed model analyses, patients having total gastrectomy, advanced cancer and hemipancreaticosplenectomy, but not complications had poorer QOL than those without. D1 and D3 patients showed no significant difference in QOL. The results suggest that changes of QOL were largely due to scope of gastric resection, disease status and distal pancreaticosplenectomy, rather than the extent of lymph node dissection. This indicates that nodal dissection can be performed for a potentially curable gastric cancer.

Esophagogastric Junction Adenocarcinoma According to Siewert Classification in Taiwan

BackgroundThe incidence of adenocarcinoma of the esophagogastric junction (AEG) is rapidly increasing. We evaluated the clinicopathological difference and outcomes of Taiwanese patients with AEG according to the Siewert classification.MethodsData were prospectively collected between December 1987 and July 2007. Two hundred thirty-one patients underwent curative resection of AEG at Taipei Veterans General Hospital and were divided into different Siewert types. The clinicopathological characteristics, operative morbidity, survival, and initial recurrence pattern were compared between the different types.ResultsFifty-one type II and 180 type III cancer patients were studied. Subtotal esophagectomy via a left thoracotomy (19.6% vs 2.8%), smaller tumor size (4.43xa0±xa02.04 vs. 5.35xa0±xa02.03xa0cm), and more combined organ resection (60% vs. 43.1%) were more common in type II than type III cancer. Multivariate analysis showed that three independent risk factors for death were gender, tumor size, and lymphovascular invasion. There were long-term survivors among the patients with lesser curvature site lymph node metastasis, whereas metastasis to the lymph nodes of the distal stomach and along the greater curvature site was associated with poor prognosis. The 5-year survival was similar between type II and type III cancer (59.6% vs. 63.5%, Pxa0=xa00.947).ConclusionsLymphovascular invasion, tumor size, and gender were determined to be three independent factors of survival after curative resection for AEG, and Siewert type was not associated with differences in survival.

Comparison of the Survival Difference Between AJCC 6th and 7th Editions for Gastric Cancer Patients

BackgroundThe AJCC 7th edition changes the classification of T- and N-factors and the TNM stage of gastric cancer. We evaluated its prognostic impact.MethodsFrom December 1987 to December 2006, a total of 1,380 patients underwent curative surgery for gastric cancer at the Department of Surgery, Taipei Veterans General Hospital, with a retrieved lymph node number ≥15. Survival was compared for disease classified according to the AJCC 6th and 7th editions.ResultsThere is a significant difference in 5-year survival between T2 and T3 gastric cancer classified according to the AJCC 7th edition (75.2 vs. 54.9%, pxa0<xa00.001), as well as between N1 and N2 (71.4 vs. 44.1%, pxa0<xa00.001). Although patients with N3a had a better 5-year survival than did those with N3b (27.6 vs. 11.3%, pxa0<xa00.001), the N3 categories were combined and not applied in the TNM stage in the 7th edition. Multivariate analysis using Cox’s proportional hazards model with a forward logistics regression stepwise procedure demonstrates that age, N category of 6th edition, and T and N categories of 7th edition are independent prognostic factors; however, T category of 6th edition is no longer significant. Furthermore, the discriminative power of survival difference between each TNM stage seems to be comparable between the 6th and 7th editions.ConclusionsThe AJCC 7th edition provides a more stratified survival difference in staging of gastric cancer. Future division of N3a and N3b in the classification of the TNM stage is recommended.

Microsatellite instability is associated with a better prognosis for gastric cancer patients after curative surgery.

BackgroundMicrosatellite instability (MSI) is one of the leading mechanisms for the carcinogenesis of gastric cancer. Its prognostic value is controversial.MethodsBetween May 1988 and Oct 2003, a total of 214 gastric cancer patients undergoing curative surgery were enrolled, and their MSI statuses were classified as MSI-H (high) or MSI-L/S (low/stable). The clinicopathologic characteristics of MSI-H and MSI-L/S gastric cancers were compared.ResultsThe MSI-H tumors accounted for 11.7xa0% (nxa0=xa025) of the 214 total gastric cancers. Although not statistically significant, the MSI-H gastric cancers were more frequently located in the lower third of the stomach (64xa0% vs. 49.2xa0%) and were more often the intestinal type (72xa0% vs. 61.4xa0%) compared to the MSI-L/S gastric cancers. The MSI-H gastric cancers had a significantly better 5-year overall survival (OS) rate (68xa0% vs. 47.6xa0%, pxa0=xa00.030) and a trend of a better 3-year disease-free survival rate (71.8xa0% vs. 55.2xa0%, pxa0=xa00.076) compared to the MSI-L/S gastric cancers. A multivariate analysis revealed that pathologic TNM stage and MSI status were the independent prognostic factors for OS after curative surgery.ConclusionsCompared to MSI-L/S tumors, MSI-H tumors are associated with a better OS rate for gastric cancer patients after R0 resection.

Factors Associated with Recurrence Within 2 Years After Curative Surgery for Gastric Adenocarcinoma

BackgroundDespite curative surgery for gastric cancer, many patients die of recurrent cancer. Few studies have investigated the time to recurrence after curative resection for gastric cancer.MethodsData were collected prospectively between December 1987 and December 2006. A total of 1,549 patients underwent curative resection of adenocarcinoma of the stomach at Taipei Veterans General Hospital. Among them, 419 patients had recurrence; they were divided into early recurrence (<2xa0years) and late recurrence (≥2xa0years). The clinicopathological characteristics, survival time after recurrence, and recurrence patterns were compared between the two groups.ResultsMultivariate analysis showed that stage III gastric cancer patients with early recurrence had larger tumors and more lymph node metastasis than patients with late recurrence, while no difference between early and late recurrence was observed in stage I and II patients. Early recurrence was associated with more distant metastasis than was late recurrence. Patients with advanced TNM stage tended to die within 2xa0years after recurrence.ConclusionsGastric cancer patients with larger tumors and more lymph node metastasis tended to have early recurrence, especially stage III patients. Advanced TNM stage was associated with early cancer death after recurrence.

Impact of Body Mass Index on Postoperative Outcome of Advanced Gastric Cancer After Curative Surgery

IntroductionThe impact of body mass index (BMI) on the outcome of advanced gastric cancer surgery is controversial. Between December 1987 and December 2006, a total of 947 advanced gastric cancer patients receiving curative resection with retrieved lymph node number >15 were studied and divided into three groups according to BMI (<25, 25–30, and >30xa0kg/m2).Results and DiscussionWith regard to comorbidities present prior to surgery, higher BMI patients were more likely to have heart disease, type 2 diabetes, and hypertension than lower BMI patients. Compared with BMI <25xa0kg/m2, higher BMI patients had longer operative time and more surgery-related morbidity. Multivariate Cox proportional-hazard analysis showed that age, pathological T and N categories, and lymphovascular invasion were independent prognostic factors. The initial recurrence patterns, 5-year overall survival, and cancer-specific survival were similar among the three groups.ConclusionOnly in stage III gastric cancer with BMI less than 25xa0kg/m2 patients receiving total gastrectomy had a more advanced pathological N category and a worse prognosis compared to those receiving subtotal gastrectomy. Higher BMI was associated with longer operative time and more surgery-related morbidity than lower BMI. BMI alone is not an independent prognostic factor.

Combined splenectomy does not improve survival in radical total gastrectomy for advanced gastric cardia cancer

BACKGROUND/AIMSnSplenectomy is the most common combined organ resection in the surgical management for gastric cardia cancer. The role of combined splenectomy is still controversial.nnnMETHODOLOGYnFrom January 1998 to December 2006, a total of 174 patients received radical total gastrectomy for advanced adenocarcinoma of cardia. Patients with previous gastric surgery or tumor invasion of pancreas or spleen were excluded. Among them, 115 patients were enrolled in this study. Patients were divided into group 1 (splenectomy, n=47) and group 2 (spleen preservation, n=68). Their clinicopathological characteristics were compared.nnnRESULTSnMultivariate analysis showed that only tumor size and lymphovascular invasion were two independent indicators of survival. The surgically-related morbidity and mortality rates were similar between the two groups. Among the 3 patients with splenic hilar lymph nodes metastasis, all of them had large tumor size (=4cm), advanced stage (stage III and IV) and tumor center located at the posterior wall of stomach. The 5-year overall survival for advanced cancer was similar (57.1% vs. 60.2%, p=0.681).nnnCONCLUSIONSnSplenectomy does not improve overall survival in the management of advanced gastric cardia cancer. Splenectomy has limited clinical benefits except for large advanced tumors located at the posterior wall of stomach.

Peritoneal recurrence in serosa-negative gastric adenocarcinoma after curative surgery

BACKGROUND/AIMSnThe rate of recurrence increases in proportion to the degree of tumor depth, even after curative resection for gastric adenocarcinoma. Serosal exposure is considered as an important risk factor of peritoneal recurrence. However, some patients with serosa-negative cancer were found to have peritoneal recurrence. There are few reports concerning risk factors of peritoneal recurrence in serosa-negative gastric adenocarcinoma. The aim of this study is to evaluate the incidence and risk factors of peritoneal recurrence in serosa-negative gastric adenocarcinoma after curative resection.nnnMETHODOLOGYnTotal 1128 serosa-negative gastric cancer patients (574 pT1, 251 pT2, 303 pT3) diagnosed as gastric adenocarcinoma that underwent R0 resection from 1988 to 2005 were enrolled.nnnRESULTSnPeritoneal recurrence was observed in 50 (4.4%) patients, including 3 pT1, 3 pT2 and 44 pT3 patients. The incidence of peritoneal recurrence increased significantly with tumor invading subserosa (pT3). Multivariate analysis showed that the independent risk factor of peritoneal recurrence was tumor depth.nnnCONCLUSIONSnThe incidence of peritoneal recurrence in serosa-negative cancer is low, and tumor depth is a significant risk factor. We should be aware of peritoneal recurrence during follow-up, especially for patients with subserosal tumor invasion.