Kunihiro Iwata

Focus on the Conditions of Resection and Reconstruction in Gastric Cancer

To assess the roles of the extent of gastric resection and duodenal food passage reconstruction in gastric cancer, we examined a consecutive series of 1,061 patients who underwent total or partial (proximal and distal) gastrectomies with or without duodenal food passage reconstruction between August of 1974 and January of 2002, and received gastrectomies with D2–3 lymph node dissection. Patients who underwent distal or proximal gastrectomy were found to have significantly better survival rates than those who underwent total gastrectomy in stages 1A (10-year survival: 86.6 and 78.9 vs. 61.6%), 2 (56.5 and 65.6 vs. 34.4%), 3A (45.9 and 33.3 vs. 15.2%), and 4 (5-year survival rates: 23.7 and 50.0 vs. 7.1%). Additionally, patients with duodenal food passage reconstruction or double tract reconstruction also showed significantly better survival rates than those without duodenal food reconstruction in stages 1A (10-year survival: 86.4 and 82.5 vs. 61.7%), 1B (69.9 and 90.6 vs. 54.1%), 2 (60.5 and 63.3 vs. 16.5%), and 3A (39.9 and 47.4 vs. 23.1%). In multivariate analysis, the independent prognostic factors were age at operation, depth of tumor, duodenal food passage reconstruction, and lymph node metastasis. Our results indicate that both the extent of gastric resection and duodenal food passage reconstruction were important factors in the outcome of gastric cancer patients, and that surgeons should perform minimal gastric resection with preservation of the duodenal food passage when the gastric stump is tumor-free.

HLA Can Provide a Personalized Therapy for Gastric Cancer as a MicroEnvironmental Genetic Factor

Background and Purpose: Based on the homogenous human leukocyte antigen (HLA) properties of the Japanese population, patients who have undergone examination of their HLA antigens have exhibited more beneficial outcomes than those without HLA examination. This study aimed to evaluate whether HLA type and location of the institutes and hospitals where patients were enrolled affected patient outcomes. Materials and Methods: A total of 1753 patients from member hospitals of the Japanese Society of Strategies for Cancer Research and Therapy throughout Japan were enrolled in this study from August 1977 to August 2005. HLA antigens were serologically tested using the NIH standard microlymphocytotoxicity method for HLA-A, -B, -C, - DR and -DQ. We used a method of quantification for the response pattern and classified similar HLA antigens into four groups: type 1, 2, 3 or 4, and classified patients into four groups: patients who received effective therapy, ineffective therapy, or neither effective nor ineffective therapy, and unclassified. Effective therapy was defined as therapy that resulted in a patients survival for a period of at least 5 to 10 years, and ineffective therapy as a therapy that resulted in a patients survival for a period of less than 5 years. The location of the institutes and hospitals where patients were enrolled was classified into three groups: eastern Japan, western Japan and Tokai University. Conclusions: There were no significant differences among HLA types, the locations and patient outcomes. Our idea is promising as a path toward individual treatment. HLA information could provide personalized therapy based on the homogenous HLA properties of the Japanese population.

Gastric Acid Secretion and Serum Gastrin Levels in Gastric Cancer

We investigated the association between gastric acid secretion, serum gastrin levels, and the differentiation of tumor cells in gastric cancer.Gastric acid output after stimulation by tetragastrin, and serum gastrin levels after stimulation by a test meal were, examined in 128 primary gastric cancer patients, in whom the tumor had invaded the mucosa. After tumors were histologically confirmed as adenocarcinomas, the patients underwent gastrectomy. Gastric ulcer patients showed decreases in both integrated gastrin response (T-IGR) after a test meal, and in gastric acid secretion related to their age. On the other hand, early gastric cancer patients showed decrease in acid secretion but an increase in T-IGR.

Immunosuppressive Acidic Protein and Postoperative Immunotherapy in Gastric Cancer

One hundred ninety-five gastric cancer patients who underwent total gastrectomy were examined for serum immunosuppressive acidic protein (IAP). Multivariate analysis utilizing Cox’s model was performed with seven variables including as age, sex, pTNM stage, postoperative adjuvant therapy, preoperative serum levels of IAP and histopathological grading. Postoperative chemotherapy with or without PSK was a significant prognostic factor in patients with abnormal levels of IAP. These results indicate that if patients with abnormal levels of IAP who had immunosuppressive status, they showed good results with postoperative immunotherapy, probably in combination with splenectomy.

HLA antigens and lymph node metastasis in gastric cancer can HLA antigens be indicators of local resection of tumor with preservation of regional lymph node

239例の胃癌切除例の術前にHLA抗原とPPD皮膚皮内反応, 急性相反応物質, NK細胞, リンパ球サブセットを測定し, リンパ節転移と対比検討したところ, HLAB40, Bw61, Cw3抗原はリンパ節転移抑制抗原, A9 (24) 抗原はリンパ節促進抗原であると考えられた. 深達度m-sm症例では, HLA抗原を測定することによってリンパ節転移の状態が106例中89例 (84.0%) 同定可能であった. リンパ節転移陰性症例のPPD皮膚皮内反応, 急性相反応物質, NK細胞, リンパ球サブセットの検討から, B40抗原陽性例では急性相反応物質が低値, OKT4が高値, OKT8が低値, Leu7が低値をA9 (24) では急性相反応物質が高値, OKT4/8が低値, Leu7, Leu11が高値を示した. 以上より, 胃癌の病態, 特にリンパ節転移に関与する遺伝的因子が主要組織適合性複合体遺伝子に強いかかわりをもつ可能性が考えられた. 術前のHLA抗原測定によりリンパ節転移が予測され, 胃癌の縮小手術が可能と思われる.