Masato Nomura

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.

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.

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.

Impact of splenectomy in patients with gastric adenocarcinoma of the cardia.

Previous reports have suggested that splenectomy treatment of gastric carcinoma of the cardia results in poor patient outcome, but the reason for this is unclear. This study aimed to clarify the impact of splenectomy for gastric carcinoma patients. A total of 118 patients with gastric carcinoma of the cardia were enrolled in this study. The characteristics of patients with lymph node metastasis at the splenic hilum were determined, and the effects of lymph node dissection or splenectomy on postoperative morbidity, mortality, and pattern of recurrence were evaluated. Advanced tumors were common in patients with lymph node metastasis at the splenic hilum, Siewert type III, greater curvature sites, larger and deeper tumors, multiple metastatic lymph nodes, and high incidences of para-aortic lymph node metastasis frequently observed. The effectiveness of lymph node dissection of the splenic hilum was low and equal to that of dissection of the para-aortic lymph nodes. Postoperative morbidity, as represented by pancreatic fistula, was high following splenectomy or pancreaticosplenectomy, but patient mortality did not occur. Hematogenous metastasis was common, as well as peritoneal metastasis after curative gastrectomy. Splenectomy should be limited in those patients with gastric cardia tumors invading the spleen or with metastatic bulky lymph nodes extending to the spleen.

Video-assisted thoracoscopic esophagectomy with a voice-controlled robot: the AESOP system.

The authors attempted to clarify the feasibility and safety of thoracoscopic esophagectomy with a voice-controlled robot, the AESOP system (3000 HR), and further determine whether innovative surgical equipment could allow the performance of complex thoracoscopic esophagectomy. Thoracoscopic surgery with a voice-controlled robot system has already been used in single-surgeon lung resection. Intra-operative and postoperative outcomes were compared between patients receiving hand-assisted laparoscopic surgery (HALS) and video-assisted thoracoscopic surgery (VATS) with the AESOP system (n = 15) and patients receiving open surgery (n = 30). In the AESOP group, the volume of blood loss was significantly less, but the total operation time was longer than in the open group. There were no significant differences in postoperative outcomes or the incidences of morbidity and mortality between the two groups. The surgeon using the AESOP system could obtain a stable, close-up, and long-lasting operative view. Laparoscopic and thoracoscopic surgery with the AESOP system has the potential to enable a single surgeon to perform a complex surgical procedure like esophagectomy.

Comparative evaluation of gastric carcinoma staging: Japanese classification versus new american joint committee on cancer/international union against cancer classification.

AbstractBackground: The TNM and Japanese classifications of regional lymph node spread (N categories) for gastric cancer differ, whereas the classifications of local extent (T categories) are identical. This study was designed to compare these staging systems and devise a more rational system for gastric carcinoma. Methods: A series of 1244 patients with gastric cancer were enrolled in the study. Survival rates were evaluated to clarify which aspects of each staging system (feasibility, reproducibility, and accuracy of prognostic stratification) were superior. Results: The TNM and Japanese classification systems differ in their categorizations of lymph node spread. A significant difference in survival rate was observed in lymph node metastasis classified as N1 and N2 by the Japanese classification and then subclassified by the TNM classification, although there was no significant difference in the survival in cases of lymph node metastasis classified by TNM into pN1 and pN2 and then subclassified by the Japanese classification. Among patients with M1 metastasis (number 16 a2 and b1 in Japanese classification) in the TNM classification, there was a significant difference in survival. A new classification that included the para-aortic lymph nodes (number 16 a2 and b1) as regional lymph nodes within the TNM classification provided homogeneity and an improvement in staging. Conclusions: TNM classification was more rational and homogenous than Japanese classification. New classification could lead to worldwide uniformity in the description of patients and make possible uniform interinstitutional comparisons of surgical results.

Clinicopathological Features of Gastric Carcinoma in Younger and Middle-Aged Patients: A Comparative Study

Gastric carcinoma is relatively rare in patients under the age of 40. This study was undertaken to clarify the clinicopathological characteristics and surgical outcomes of gastric carcinoma in younger patients compared with those of middle-aged patients. The surgical results from 131 younger patients (aged ⩽40 years) and 918 middle-aged patients (aged 55–65 years) were compared retrospectively. Female gender, undifferentiated tumor type and lymphatic invasion were significantly more common in the younger patients. Survival time did not differ between the two groups. The depth of tumor invasion was the only prognostic factor in younger patients, whereas macroscopic appearance, tumor diameter, depth of invasion, lymph node metastasis, and venous invasion were all significant prognostic factors in middle-aged patients. Peritoneal recurrence was significantly more common in younger patients. A family history of gastric adenocarcinoma was observed in 25.9% of younger patients, but this did not affect survival outcomes. As depth of invasion affects prognosis independently, and peritoneal metastasis is the predominant pattern of recurrence, it is essential to establish an optimal prophylactic treatment for peritoneal metastasis to improve surgical outcomes in younger patients with advanced gastric cancer.

Lymph node status in patients with submucosal gastric cancer.

BackgroundThe aim of this study was to clarify the lymph node status in patients with submucosal gastric cancer.MethodsBetween April 1994 and December 1999, 615 patients with histologically proven submucosal gastric cancer who underwent curative resection were included in this study. The results of the surgery and predictive factors for lymph node metastasis were evaluated by univariate and multivariate analyses. The accuracy of the predictive factors was assessed in a second population of a further 186 patients.ResultsLymph node metastasis was observed in 119 patients (19.3%). Multivariate analysis showed that pathologic tumor diameter (≥20 mm) and lymphatic invasion were independent predictive factors for lymph node metastasis. The incidence of lymph node metastasis without these 2 predictive factors was 1.8% (2 of 113), and it was 51.2% (85 of 166) with the 2 predictive factors, 9.5% (14 of 148) in tumors <20 mm in diameter, and 5.3% (22 of 414) in tumors without lymphatic invasion. Among patients with a tumor <20 mm in diameter, the incidence of lymph node metastasis was significantly reduced in those with a differentiated tumor: 4.2% (4 of 95). These results were almost identical to those observed in the second population.ConclusionsLymph node status can be accurately predicted on the basis of pathologic tumor diameter <20 mm, lymphatic invasion (absence), and histological type (differentiated) in patients with submucosal gastric cancer. Less extensive surgery for these patients might be reconsidered after confirmation of the reproducibility of the results of this study by an appropriately designed prospective clinical trial.