Hirotoshi Akiyama

Learning curve for laparoscopy-assisted distal gastrectomy with regional lymph node dissection for early gastric cancer.

An assessment of the learning curve of laparoscopy-assisted distal gastrectomy (LADG) might encourage its worldwide spread among inexperienced surgeons. One hundred sixty-seven patients with early gastric cancer were enrolled in this study: 67 underwent conventional open distal gastrectomy and 100 underwent LADG after classification into 5 groups of 20 according to the surgeons level of experience. Patient characteristics and operative findings were compared between groups. Operation time was significantly longer, time to first flatus earlier, and blood loss reduced in the LADG groups compared with the open distal gastrectomy group. Surgeons with experience of 60 cases performed operations of similar times in both groups, and blood loss decreased with experience of 20 cases. There was no operative conversion, the frequency of nonsteroidal anti-inflammatory drugs administered were significantly less, and length of hospital stay were shorter by surgeons with experience of 60 cases. LADG is a technically feasible surgical procedure, depending on the surgeons technical proficiency. Experience of at least 60 cases of LADG seems to result in satisfactory patient outcomes.

Therapeutic strategy for signet ring cell carcinoma of the stomach

Reports of clinicopathological characteristics and prognosis in patients with signet ring cell carcinoma (SRC) of the stomach are conflicting.

Predictive factors for surgical complications of laparoscopy- assisted distal gastrectomy for gastric cancer

BackgroundSome studies have found high incidences of intraoperative and postoperative complications for patients with gastric cancer. To determine the predictive factors for the surgical complications of laparoscopic gastric surgery, surgical outcomes were evaluated.MethodsBetween April 2002 and December 2007, 152 patients with preoperatively diagnosed early gastric cancer who underwent laparoscopy-assisted distal gastrectomy (LADG) were enrolled. Visceral (VFA) and subcutaneous fat areas (SFA) were assessed by Fat Scan software. The predictive factors for surgical complications of LADG were evaluated by univariate and logistic regression analyses.ResultsOf 152 patients, conversion to open surgery due to uncontrollable bleeding was observed in nine male patients, and postoperative complications were detected in seven male and one female patient (four anastomotic leakage, two intraabdominal abscess, one pancreatic fistula, and one lymphorrhea). High body mass index (BMI) and high VFA independently predicted conversion to open surgery and postoperative complications. VFA was significantly higher, operation time was longer, blood loss was greater, and SFA was lower in male than in female patients, whereas no significant difference was observed in BMI between male and female patients.ConclusionsHigh BMI and high VFA can predict technical difficulties during laparoscopic gastric surgery and postoperative complications. Particularly, LADG should be performed cautiously to prevent surgical complications for male patients with high VFA. Predictive impact of VFA should be further determined in a larger set of patients.

Comparison of Surgical Results of D2 Versus D3 Gastrectomy (Para-Aortic Lymph Node Dissection) for Advanced Gastric Carcinoma: A Multi-Institutional Study

Curative gastrectomy is a promising approach for the treatment of gastric cancer; however, the optimal extent of lymph node dissection for advanced cancer remains controversial. The aim of this multi-institutional study was to evaluate the feasibility of D3 gastrectomy (para-aortic lymph node dissection) for advanced gastric cancer. The surgical results of D2 and D3 gastrectomy (para-aortic lymph node dissection) were retrospectively compared. A series of 580 advanced gastric cancer patients were registered between 1992 and 2000. Of these, 430 underwent D2 gastrectomy and 150 underwent D3 gastrectomy. Survival time, prognostic factors, postoperative morbidity/mortality, and pattern of recurrence were compared. There was no significant difference in survival time between D2 and D3 patients. However, the survival times of D3 patients with tumor diameters measuring 50 to 100 mm or with pN1 disease were significantly longer than those of the corresponding D2 patients. Analysis of the survival of patients with tumor diameters measuring 50 to 100 mm revealed that D3 gastrectomy conferred a survival advantage only to patients with pN2 disease. The incidence of lymphatic recurrence was lower in D3 patients with 50- to 100-mm tumors than in the corresponding D2 patients. D3 gastrectomy might be beneficial in patients with advanced pN2 gastric cancer within the group with tumors measuring 50 to 100 mm. A randomized controlled trial of patients with 50- to 100-mm tumors should be performed to test the validity of this preliminary result.BackgroundCurative gastrectomy is a promising approach for the treatment of gastric cancer; however, the optimal extent of lymph node dissection for advanced cancer remains controversial. The aim of this multi-institutional study was to evaluate the feasibility of D3 gastrectomy (para-aortic lymph node dissection) for advanced gastric cancer. The surgical results of D2 and D3 gastrectomy (para-aortic lymph node dissection) were retrospectively compared.MethodsA series of 580 advanced gastric cancer patients were registered between 1992 and 2000. Of these, 430 underwent D2 gastrectomy and 150 underwent D3 gastrectomy. Survival time, prognostic factors, postoperative morbidity/mortality, and pattern of recurrence were compared.ResultsThere was no significant difference in survival time between D2 and D3 patients. However, the survival times of D3 patients with tumor diameters measuring 50 to 100 mm or with pN1 disease were significantly longer than those of the corresponding D2 patients. Analysis of the survival of patients with tumor diameters measuring 50 to 100 mm revealed that D3 gastrectomy conferred a survival advantage only to patients with pN2 disease. The incidence of lymphatic recurrence was lower in D3 patients with 50- to 100-mm tumors than in the corresponding D2 patients.ConclusionsD3 gastrectomy might be beneficial in patients with advanced pN2 gastric cancer within the group with tumors measuring 50 to 100 mm. A randomized controlled trial of patients with 50- to 100-mm tumors should be performed to test the validity of this preliminary result.

Outcomes of mass screening for gastric carcinoma.

BackgroundTherapeutic results of gastric cancer have been improved by early detection of gastric cancer with the mass screening system in Japan. The objective of our study was to assess the efficacy of mass screening for gastric cancer by using a barium meal.MethodsA series of 1050 patients (364 in the screened group and 686 in the nonscreened group) were included in this study from April 1992 to March 2000. Patient characteristics, therapeutic results, and prognostic factors were compared in the two groups.ResultsThe screened patients tended to be younger and male, with tumors in the middle third of the stomach that were of a macroscopically superficial type, with a smaller diameter, and at an earlier stage. They had fewer metastatic lymph nodes and underwent more frequent curative resection. Among the screened patients with curatively resected disease, tumors tended to be of a smaller diameter, and there were fewer metastatic lymph nodes in both early and advanced cases. Disease-specific survival was significantly better in the screened cases among all registered and curatively resected patients. Mass screening achieved significantly better surgical results in early or advanced gastric cancer patients who received curative resection. Multivariate analysis revealed that mass screening was an independent prognostic factor (hazard ratio, .3949; P < .0001), together with depth of invasion, lymph node metastasis, age, and tumor diameter.ConclusionsMass screening by using barium meal examination for gastric cancer detects cancer at an early stage and produces good therapeutic results.

Application of the transorally inserted anvil (OrVil) after laparoscopy-assisted total gastrectomy.

BackgroundLaparoscopy-assisted total gastrectomy (LATG) is not a commonly performed procedure due to the surgical difficulty associated with reconstruction. Although various reconstruction methods have been reported, a standard technique has not yet been established. In this study, we compared the short-term outcomes of LATG reconstructed by mini-laparotomy and by the newly developed transorally inserted anvil (OrVil™).MethodsFrom April 2006, a series of 45 patients underwent LATG. Of these, 15 were reconstructed by mini-laparotomy and 30 by OrVil™. Short-term outcomes were compared between the two groups.ResultsOperation time was significantly shortened and intraoperative blood loss significantly reduced by the use of OrVil™. The postoperative course, including morbidity, did not differ between the two groups.ConclusionsLATG using OrVil™ for the treatment of early gastric cancer is a technically feasible surgical procedure with sufficient lymph node dissection, satisfactory early recovery, and acceptable morbidity. It will be necessary to perform this novel technique in a large number of patients to confirm its feasibility.

Risk factors for lymph node metastasis in histologically poorly differentiated type early gastric cancer.

BACKGROUND We retrospectively evaluated the predictive factors for lymph node metastasis in poorly differentiated early gastric cancer (poorly differentiated tubular adenocarcinoma, signet-ring cell carcinoma, mucinous adenocarcinoma) in order to examine the possibility of endoscopic resection for poorly differentiated early gastric cancer. METHODS A total of 573 patients with histologically poorly differentiated type early gastric cancer (269 mucosal and 304 submucosal), who had undergone curative gastrectomy, were enrolled in this study. Risk factors for lymph node metastasis were evaluated by univariate and logistic regression analysis. RESULTS Lymph node metastasis was observed in 74 patients (12.9%) (6 with mucosal cancer and 68 with submucosal cancer). By univariate analysis risk factors for lymph node metastasis were lymphovascular invasion (LVI) (presence), depth of invasion (submucosa), and tumor diameter (> 20 mm), ulcer or ulcer scar (presence), and histological type (mucinous adenocarcinoma). By multivariate analysis, risk factors for lymph node metastasis were LVI, depth of invasion, and tumor diameter. In mucosal cancers, the incidence of lymph node metastasis was 0% irrespective of LVI in tumors smaller than 20 mm, and 1.7% in tumors 20 mm or larger without LVI. In submucosal cancers, the incidence of lymph node metastasis was 2.4% in tumors smaller than 20 mm without LVI. CONCLUSIONS A histologically poorly differentiated type mucosal gastric cancer measuring less than 20 mm and without LVI may be a candidate for endoscopic resection. This result should be confirmed in a larger study with many patients.

Exosomal miRNAs from Peritoneum Lavage Fluid as Potential Prognostic Biomarkers of Peritoneal Metastasis in Gastric Cancer

Peritoneal metastasis is the most frequent type of recurrence in patients with gastric cancer (GC) and is associated with poor prognosis. Peritoneal lavage cytology, used to evaluate the risk of peritoneal metastasis, has low sensitivity. Here, we assessed the diagnostic potential of exosomal miRNA profiles in peritoneal fluid for the prediction of peritoneal dissemination in GC. Total RNA was extracted from exosomes isolated from six gastric malignant ascites (MA) samples, 24 peritoneal lavage fluid (PLF) samples, and culture supernatants (CM) of two human gastric carcinoma cell lines that differ in their potential for peritoneal metastasis. Expression of exosomal miRNAs was evaluated with Agilent Human miRNA microarrays and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The microarray analysis indicated a low variability in the number and signal intensity of miRNAs detected among the samples. In the six MA fluids, miR-21 showed the highest signal intensity. We identified five miRNAs (miR-1225-5p, miR-320c, miR-1202, miR-1207-5p, and miR-4270) with high expression in MA samples, the PLF of serosa-invasive GC, and the CM of a highly metastatic GC cell line; these candidate miRNA species appear to be related to peritoneal dissemination. Differential expression of miR-21, miR-320c, and miR-1225-5p was validated in the PLF of serosa-invasive and non-invasive GC by qRT-PCR and miR-21 and miR-1225-5p were confirmed to be associated with serosal invasion in GC. PLF can be used to profile the expression of exosomal miRNAs. Our findings suggest that miR-21 and miR-1225-5p may serve as biomarkers of peritoneal recurrence after curative GC resection, thus providing a novel approach to early diagnosis of peritoneal dissemination of GC.

Clinicopathologic Characteristics and Surgical Outcomes of Mucinous Gastric Carcinoma

BackgroundThe clinicopathologic characteristics of mucinous gastric carcinoma (MGC), an uncommon subtype of gastric carcinoma, were examined by comparing 45 MGC and 1255 non-MGC (NGC) cases.MethodsOf 1300 gastric cancer patients, 1184 (early, n = 568; advanced, n = 616) underwent potentially curative or palliative resection. Age, sex, tumor location, tumor diameter, macroscopic appearance, depth of invasion, lymph node metastasis, lymphatic invasion, and venous invasion were monitored.ResultsIn all registered patients, MGC patients’ characteristics were as follows: advanced-stage disease (P = .0293), macroscopically ill-defined tumors (P = .0051), deeper invasion (P = .0046), and more lymph node involvement (P = .0008). Although there were no significant differences between curatively resected MGC and NGC advanced-cancer patients, in curatively resected early-cancer patients, depth of invasion (P = .0060) and lymphatic invasion (P = .0374) were significantly different. Survival time in all registered patients was shorter for MGC patients (P = .0489). Survival of curatively resected advanced and early gastric cancer patients was not significantly different. Age, macroscopic appearance, tumor diameter, depth of invasion, lymph node metastasis, and curability, but not histological type, were independent prognostic factors in all registered patients. Histological type also did not influence prognosis after curative resection. MGC patients had significantly more metastatic lymph nodes and lymphatic and venous invasion. Survival was significantly different (P = .0450) between all patients with undifferentiated and differentiated MGC, but not in curatively resected patients.ConclusionsMGC patients’ poor prognosis correlates with advanced disease at diagnosis. Therapeutic and follow-up plans after curative resected MGC and NGC should remain the same, possibly with alterations according to the former’s histological subtype.

Significance of long-term follow-up of early gastric cancer.

BackgroundTherapeutic outcomes for most patients with early gastric cancer are favorable. However, mortality among these patients remains a concern. Improvements in therapeutic outcomes are being sought by studying the timing and causes of death. Here, the results of surgery were evaluated to assess the appropriate treatment and follow-up schedule for early gastric cancer.MethodsA total of 1169 patients with early gastric cancer underwent curative gastrectomy between 1992 and 1999. Survival time, prognostic factors, cause of death, and time of death were evaluated retrospectively.ResultsMultivariate analysis of disease-specific survival identified lymph node metastasis as an independent prognostic factor. The anatomical extent of lymph node metastasis and the number of metastatic lymph nodes influenced the rate of recurrence. Multivariate analysis of overall survival identified age as a prognostic factor. A total of 91 patients (7.8%) from the study group died: 56 from comorbid diseases, 21 from gastric cancer, and 14 from other second primary cancers. Death from gastric cancer was frequently observed within 5 years of surgical resection, whereas death from other diseases usually occurred after 5 years. Patients who died as a result of diseases other than gastric cancer tended to be older.ConclusionsAppropriate lymph node dissection is necessary for patients with early gastric cancer, particularly those with risk factors associated with lymph node metastasis. Meticulous follow-up protocols that can detect second primary cancers, together with the development of treatments for comorbid diseases, are required to improve survival.