Itasu Ninomiya

Expression of C-erbB-2 oncoprotein in gastric carcinoma. Immunoreactivity for C-erbB-2 protein is an independent indicator of poor short-term prognosis in patients with gastric carcinoma

Correlations of c‐erbB‐2 protein expression with clinical outcomes of gastric carcinomas were studied in 189 gastric carcinomas. There were 23 (12.2%) carcinomas with evidence of c‐erbB‐2 protein in which the reaction was localized to the cell membrane. There was no significant association between c‐erbB‐2 staining and the macroscopic or histologic type of the carcinomas. c‐erbB‐2‐stained tumors were more likely to be associated with serosal invasion, nodal involvement, and peritoneal metastasis, than c‐erbB‐2‐unstained ones. In addition, c‐erbB‐2 was stained in none of early gastric carcinomas. The 5‐year survival rates of the c‐erbB‐2 protein‐positive and the protein‐negative group were 11% and 50%, respectively. When the c‐erbB‐2 tissue status and seven clinicopathologic variables as conventional prognostic factors were entered simultaneously into the Cox regression model, serosal invasion, hepatic metastasis, peritoneal metastasis, nodal status, and c‐erbB‐2 tissue status emerged as independent prognostic variables. The results suggested that c‐erbB‐2 protein expression might be enhanced in advanced stages during the progression of gastric carcinoma. In this particular group of patients, immunoreactivity for c‐erbB‐2 protein is an indicator of poor short‐term prognosis.

Impact of the Biliary Diversion Procedure on Carcinogenesis in Barrett's Esophagus Surgically Induced by Duodenoesophageal Reflux in Rats

Objective:To determine whether the elimination of bile reflux in the established esophagojejunostomy model of Barretts esophagus (BE) will reduce or eliminate the risk of developing esophageal adenocarcinoma. Summary Background Data:Reflux of duodenal juice as well as gastric acid plays an important role in the pathogenesis of BE and adenocarcinoma. Duodenoesophageal reflux (DER) per se induces these diseases without carcinogen. However, it is unclear whether antireflux surgery induces regression of BE and prevents adenocarcinoma. Methods:Two hundred F344 male rats underwent one of following 3 operations: (1) total gastrectomy and esophagojejunostomy to induce DER, followed by killing after 20 (n = 13), 30 (n = 12), and 50 weeks (n = 30); (2) biliary diversion procedure, converted to Roux-en-Y method, to avoid bile regurgitation into the esophagus at 20 (n = 29) and 30 weeks (n = 32) after the operation to induce DER, followed by killing 50 weeks after initial operation; or (3) total gastrectomy and Roux-en-Y esophagojejunostomy followed by killing after 50 weeks served as controls (n = 28). Results:BE developed in more than half of the animals exposed to DER for 20 weeks, in more than 90% of rats with DER for 30 weeks, and in 100% of animals exposed to DER for 50 weeks. In the incidence and the length of BE, there is no difference between the animals that underwent biliary diversion at 20 (62%) and 30 weeks (94%) and those that had DER for 20 (54%) and 30 weeks (92%), respectively. Incidence of adenocarcinoma was significantly lower in the rats that underwent the biliary diversion procedure after 30 (19%) and 20 weeks (3%) than in the rats that had DER for 50 weeks (60%) (P < 0.005). None of the control animals that underwent Roux-en-Y esophagojejunostomy developed BE and carcinoma. Conclusions:It is likely that the converting procedure from the esophagojejunostomy to induce DER to biliary diversion does not lead to regression of BE but prevents the development of esophageal adenocarcinoma in the rats.

Growth fractions in gastric carcinomas determined with monoclonal antibody Ki‐67

The growth fractions of 101 gastric carcinomas were determined in situ by immunostaining with the monoclonal antibody Ki‐67 and the results correlated with the histopathologic findings, bromodeoxyuridine (BrdU) labeling index, and DNA ploidy pattern. DNA ploidy patterns were determined by flow cytometric analysis. The Ki‐67 labeling rates are rated from 4.6% to 82% (mean, 22%). A significant correlation was found between Ki‐67 labeling rates and BrdU labeling indices. Sixty‐seven percent of tumors with lymph node metastases showed Ki‐67 labeling rates of greater than 22%, whereas 33% of tumors without lymph node metastases showed Ki‐67 labeling rates of less than 22%. There was a significant correlation between these two groups. Tumors with vessel invasion more often have higher Ki‐67 labeling rates than those without vessel invasion. By the DNA ploidy classification, the mean Ki‐67 labeling rates of aneuploid tumors was significantly higher than that of diploid tumors. This method yielded similar results to those obtained by BrdU labeling and flow cytometric study. The measurement of Ki‐67 labeling rates may be useful to decide the therapeutic modalities.

Interrelationship between Transforming Growth Factor-α and Epidermal Growth Factor Receptor in Advanced Gastric Cancer

An immunohistochemical study for transforming growth factor-alpha (TGF alpha) and epidermal growth factor receptor (EGFR) was made with 167 primary tumors of advanced gastric cancer to demonstrate the potential existence of autocrine mechanism. TGF alpha stained positively in 87 (52%), and EGFR in 68 (41%) of the tumors. The authors classified the tumors into the following three groups: group 1 with neither TGF alpha nor EGFR staining positively (63 tumors); group 2 with either TGF alpha or EGFR staining positively (53 tumors); group 3 with both TGF alpha and EGFR staining positively (51 tumors). The incidence rates of macroscopically infiltrative tumors and large tumor measuring 6 cm or more in diameter were significantly higher for group 3 than for groups 1 and 2. The patients of group 3 had the poorest prognosis, with a 5-year survival rate of only 12%, while the 5-year survival rates were 45 and 36% for groups 1 and 2. There was a significant difference in survival between the patients of group 1 and those of group 3. Bromodeoxyuridine labeling indices were significantly higher in the tumors belonging to group 3 (median 15.8%) than in those of group 1 (median 10.8%). The results suggest that the autocrine mechanism between TGF alpha and EGFR may play an important role in the progression of gastric cancer, and that when such a mechanism becomes operative, prognosis may be poor.

E-cadherin and urokinase-type plasminogen activator tissue status in gastric carcinoma.

Background. E‐cadherin (ECD) is known to be an invasion suppressor gene, and urokinase‐type plasminogen activator (uPA) plays a central role in infiltration of solid cancers.

Amplification of Epidermal Growth Factor Receptor Gene and Its Relationship to Survival in Human Gastric Cancer

The correlation between the clinical features in 103 patients with primary gastric carcinoma and amplification of epidermal growth factor receptor (EGFR) gene was analyzed retrospectively. EGFR gene amplification was examined by slot-blot hybridization using DNA extracted from formalin-fixed, paraffin-embedded tissues. EGFR expression was also examined immunohistochemically using the same tissues with a monoclonal antibody that is monospecific for EGFR. In 5 of 103 cases (4.9%), a 2- to 11-fold amplification of EGFR gene was detected. Four of these 5 cases were poorly differentiated adenocarcinomas. All of them had overexpressions of EGFR. The cumulative survival rate of patients with EGFR gene amplification was significantly lower than that of the patients without amplification (p < 0.05) and all of them died within 3 years. Except for tumor size (p < 0.03), there were no significant clinicopathologic differences between the two groups. On the other hand, 41 of 103 cases (39.8%) exhibited expression of EGFR. However, there was no significant correlation between EGFR expression and clinicopathologic factors or prognosis. These results indicate that EGFR gene amplification may occur in advanced stages during the progression and be an important indicator of poor short-term prognosis in gastric carcinoma.

Detection of sentinel and non-sentinel lymph node micrometastases by complete serial sectioning and immunohistochemical analysis for gastric cancer

BackgroundWe investigated the presence and distribution of the sentinel and the non-sentinel node micrometastases using complete serial sectioning and immunohistochemical staining (IHC), to inspect whether lymph node micrometastases spread to the sentinel lymph nodes first.MethodsA total of 35 patients, who underwent gastrectomy with a sentinel lymph node biopsy for gastric cancer, were enrolled in this study. Total of 1028 lymph nodes of 35 patients having gastric cancer without metastasis of lymph node by permanent section with hematoxylin and eosin staining (H&E) were selected. There were 252 sentinel nodes and the other 776 were non-sentinel nodes. All nodes were sectioned serially and stained alternately with H&E and IHC. Lymph node micrometastases was defined as proving to be positive first either the IHC or the complete serial sectioning.ResultsMicrometastases were detected in 4 (11%) of the 35 patients, 6 (0.58%) of 1028 nodes. Of these 4 patients, 3 had micrometastases exclusively in sentinel nodes, and the other had micrometastasis in both sentinel and non-sentinel nodes. There was no patient who had the micrometasitases only in non-sentinel nodes.ConclusionThese results support the concept that lymph node micrometastasis of gastric cancer spreads first to sentinel nodes.

PTD classification: proposal for a new classification of gastric cancer location based on physiological lymphatic flow

BackgroundWe propose a new classification for the location of gastric cancer — the PTD classification (i.e., zones P, T, and D; see below), with the zones classified according to the physiological lymphatic flow.MethodsThree hundred and thirty-six patients with T1 or small T2 gastric cancer who underwent sentinel node mapping at our hospital were enrolled. The relationship between the location of the gastric cancer and the physiological lymphatic flow derived from sentinel node mapping was investigated. Lymphatic basins were defined as lymphatic zones divided by the stream of stained lymphatic canals.ResultsOne hundred and forty-six patients underwent standard gastrectomy with more than D2 dissection and the other 190 patients underwent function-preserving gastrectomy with the omission of lymph node dissection outside the lymphatic basin. In the former group, the progression pattern of lymph node metastasis was observed; nodal metastasis occurred in sentinel nodes first, and rarely extended outside the lymphatic basin. In the latter group, none of the patients have had a recurrence. The PTD classification we propose is as follows: the dividing line between the proximal region (zone P) and the transitional region (zone T) is the line that links the point of the watershed between the left gastroepiploic artery and right gastroepiploic artery, to the point that is the inflow point of the first descending branch of the left gastric artery; and the dividing line between zone T and the distal region (zone D) is an arc at a radius of 8 cm from the pylorus. There were no lymphatic basins within the right gastric artery area for tumors located in zone T.ConclusionThe advantage of the PTD classification is that if the PTD classification were to be used as a guide for gastric resection procedures, preservation of the pylorus would become possible without diminishing the prognosis in patients with cT1N0 cancer located in zone T.

Expression of Vascular Endothelial Growth Factor D Is Associated with Lymph Node Metastasis in Human Colorectal Carcinoma

Objective: Expression of vascular endothelial growth factor (VEGF)-D by tumors is associated with metastasis to lymph nodes in mice. However, there are few reports concerning the clinical significance of VEGF-D protein in human carcinoma. Methods: After confirming production of VEGF-D by eight colorectal carcinoma cell lines, we investigated relationships between the expression of VEGF-D protein, lymph node metastasis and postoperative survival in 83 colorectal carcinoma patients. mRNA levels in cell lines were evaluated using the real-time reverse transcriptase-polymerase chain reaction, and protein was detected by Western blotting in cell lines and by immunohistochemistry in resected tissues using an antibody recognizing the processed form of the molecule. Results: Immunohistochemistry showed VEGF-D-positive staining in 26 of the 83 carcinomas (31%). There was a significant relationship between the presence of VEGF-D protein and the incidence of lymph node metastasis (p < 0.01). Multivariate logistic regression analysis revealed that VEGF-D protein expression was an independent factor affecting lymph node metastasis (p < 0.01). Nonetheless, the presence or absence of VEGF-D protein had no significant impact on the survival of the patients (p = 0.15). Conclusion: These results suggest that the expression of VEGF-D protein could be useful in predicting the nodal status of colorectal carcinoma patients.

Alteration of β‐catenin expression in esophageal squamous‐cell carcinoma

β‐catenin regulates cadherin‐mediated cell‐cell adhesion and also functions as a signaling molecule. In this study, we examined the expression pattern of E‐cadherin, α‐catenin and β‐catenin in 22 cases of esophageal squamous‐cell carcinoma by Western‐blot analysis. Expression of E‐cadherin, α‐catenin and β‐catenin was lower in carcinomas than in normal esophageal mucosa in 4 cases (18.2%) for E‐cadherin, 6 cases (27.3%) for α‐catenin and 9 cases (40.9%) for β‐catenin. Expression of β‐catenin was not always correlated with that of E‐cadherin. Over‐expression of β‐catenin was observed in 3 cases (13.6%). Of 3 cases that presented with over‐expression of β‐catenin, 2 showed cytoplasmic staining by immunohistochemistry. Nuclear localization of β‐catenin was observed in one case that had higher β‐catenin level in tumor tissue (1.4‐fold higher than normal mucosa). The genomic DNA sequences of the β‐catenin and the APC gene were analyzed. No mutation of the β‐catenin gene was observed in any cases. Silent mutation of the APC gene was found in all the cases that showed over‐expression or nuclear localization of the β‐catenin protein. These results indicate that alterations of the cadherin‐catenin complex may play an important role in a sub‐set of esophageal carcinogenesis. Furthermore, it is suggested that β‐catenin over‐expression is not caused by genetic alteration of either the β‐catenin or the APC gene. Int. J. Cancer 85:757–761, 2000.