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T Ichikura

Publications and source records attributed to T Ichikura.

18 recordsLinked to original sources
PubMed1998

Relationship between nodal stage and the number of dissected perigastric nodes in gastric cancer.

To evaluate the rationality of the current nodal staging system in gastric cancer, we retrospectively analyzed 152 patients with perigastric node involvement localized to a single station, in whom the route of metastasis to distant nodes was limited. No significant differences in pathology or survival were observed between patients with stage n1 and those with stage n2-3 nodal involvement, but the mean (standard deviation) number of perigastric nodes dissected was 22.6 (12.6) in those with stage nl involvement and 18.5 (9.5) in those with stage n2-3 involvement (P = 0.04). When perigastric node involvement was localized to station 3, the mean number of dissected station 3 nodes was 7.7 (4.2) in nl patients and 5.3 (2.8) in n2-3 patients (P = 0.04). This tendency was also observed in patients with perigastric node involvement limited to either station 1 (P = 0.08) or station 6 (P = 0.11). Thus, patients with fewer perigastric nodes may have more lymphatics that bypass perigastric nodes and empty directly into distant nodes, increasing the likelihood of skip metastases. The number of positive nodes, affected to a lesser degree by lymphatic distribution than the location of positive nodes, should be incorporated into the staging criteria.

Adult↗
PubMed1998

[Telomerase activity during the cell cycle in gastric cancer cell lines].

Telomerase, a ribonucleoprotein that adds telomeric repeats onto chromosome ends, is involved in telomere length maintenance and permits unlimited cell proliferation. We examined the possibility that higher telomerase activity is associated with the replicative phase of the cell cycle using gastric cancer cell lines treated with anticancer drugs. Telomerase activity increased at the time point of S-phase accumulation in NUGC-3 cells (5 x 10(5) cells/ml) incubated with CDDP (0.5 microgram/ml), paclitaxel (0.01 microM), or VP-16 (1 microM) and in MKN-28 cells incubated with CDDP. When these cell lines were incubated with 5-fluorouracil (10 microM) or CPT (0.1 microM), the increase of telomerase activity preceded the S-phase accumulation. Our results suggest that telomerase activity be regulated by the cell cycle.

Antineoplastic Agents↗
PubMed1996

Immunohistochemical staining for the p53 protein and proliferating cell nuclear antigen in familial clustering of gastric cancer.

UNLABELLED: Purpose of this study was to assess the role of p53 gene and tumor proliferating activity in familial clustering of gastric cancer. MATERIALS AND METHODS: Among 344 patients who underwent resections for gastric cancer, 10 patients had two or more gastric cancer-affected, first-degree relatives. We classified them as the group of gastric cancer with family history (FGC). Eighty-seven patients with gastric cancer who had no relatives with any malignant neoplasm were classified as the sporadic group. The paraffin-embedded specimens were stained immuno-histochemically using monoclonal antibodies against the p53 product and proliferating cell nuclear antigen (PCNA). RESULTS: There was no significant difference in any clinicopathologic factor and the PCNA labeling index between the two groups. Staining for the p53 product was positive in 80% of the FGC group and in 38% of the sporadic group (P < 0.05). CONCLUSION: Our study suggests that overexpression of p53 protein is one of the familial factors that correlates with carcinogenesis in the stomach.

Adult↗
PubMed1996

Clinical and prognostic characteristics of papillary clear carcinoma of stomach.

Papillary clear carcinoma (PCC), a variant of gastric papillary adenocarcinoma, demonstrates the histologic features of cancer cells with clear cytoplasm and no nuclear polarity, resembling the primitive gut epithelium of the fetus. To clarify the clinical and prognostic characteristics of PCC, we examined operative specimens from 73 patients with gastric papillary adenocarcinoma. Light microscopic examination of hematoxylin and eosin (H&E) stained sections of specimens from 15 patients revealed the features of PCC. The patients with PCC demonstrated a higher incidence of Type 3 gross appearance, tumor invasion into the muscularis propria or beyond, involvement of distal lymph nodes, liver metastasis, elevated serum AFP concentrations, and palliative resections. In two subsets of patients who underwent curative resections of tumors invading the muscularis propria or beyond, those with PCC were found to have a significantly lower survival rate than those with other types of papillary adenocarcinoma (P < 0.05). PCC histology was a significant prognostic determinant according to multivariate analysis with the Cox proportional hazards model. We conclude that this subclassification of papillary adenocarcinoma, based on the cellular findings, is a useful prognostic indicator, and that intensive adjuvant therapy may be indicated for patients with the features of PCC, even if they have undergone curative resections.

Adenocarcinoma, Papillary↗
PubMed1996

Thymidylate synthase inhibition by an oral regimen consisting of tegafur-uracil (UFT) and low-dose leucovorin for patients with gastric cancer.

PURPOSE: 5-Fluorouracil (5-FU) remains a standard therapy for patients with advanced gastric cancer. There has been no study using an oral regimen with a combination of tegafur, a masked compound of 5-FU, and leucovorin in gastric cancer. The purpose of this study was to determine whether orally administered low-dose leucovorin enhances thymidylate synthase (TS) inhibition when added to tegafur-uracil (UFT) in patients with gastric cancer. METHODS: A group of 26 patients with resectable gastric cancer were assigned to one of two regimens: UFT alone or UFT plus leucovorin. UFT, equivalent to 400 mg/day tegafur, with or without 30 mg/day leucovorin, was administered orally in divided daily doses every 12 h for 3 consecutive days prior to surgery. Tumor specimens were taken immediately following gastrectomy, and the TS inhibition rate (TSIR) was determined using a ligand-binding assay. RESULTS: The TSIR was significantly higher in the UFT plus leucovorin group than in the UFT alone group (P < 0.01). The TSIR in the patients treated with UFT alone ranged between 14% and 50%, while six of the eight patients treated with UFT plus leucovorin had a TSIR of 55% or higher. The remaining two patients in the group treated with UFT plus leucovorin, with a TSIR of 31% and 44%, had undifferentiated tumors. CONCLUSION: Our results suggest that orally administered low-dose leucovorin can add to the efficacy of UFT in patients with gastric cancer, and provide preliminary data for a randomized clinical trial.

Administration, Oral↗
PubMed1995

Surgical strategy for patients with gastric carcinoma with submucosal invasion. A multivariate analysis.

BACKGROUND: Early gastric cancer can be treated by endoscopic excision or simple wedge surgical resection. Standard gastrectomy often is advised if submucosal invasion is found, even though only 15-25% of these patients have lymph node metastases. In this study, the risk of lymph node involvement was examined by multivariate analysis to develop a simple discriminant function for surgical decision making in this setting. METHODS: The authors determined factors significantly correlated with lymph node involvement in a retrospective review of 196 patients with gastric adenocarcinoma invading into, but not beyond, the submucosa. Depth and horizontal spread of cancer in the submucosa were evaluated in addition to ordinary pathologic factors. Discriminant analysis for lymph node involvement was performed using explanatory variables chosen from the results of the univariate analyses. RESULTS: Lymph node involvement correlated significantly with larger tumor size; greater dimension of submucosal invasion; deeper submucosal invasion; gross appearance of Type I, IIc + III or IIa + IIc; and severity of vessel invasion. Of the variables, the amount of lymphatic invasion, macroscopic appearance, and maximum dimension of submucosal infiltration were selected as effective predictors of lymph node involvement according to discriminant analysis. A correct discrimination of 74.8% was obtained with a linear discriminant function using these variables. Lymph node involvement was observed in 50% of the cases with a discriminant score less than -1 and in 25% of those with a score between -1 and 0, whereas no lymph node involvement was observed in those with a score greater than 2. CONCLUSIONS: Discriminant function as used in this study provided a useful criterion for additional surgery for patients with gastric carcinoma invading the submucosa who were treated initially by localized excision. Prophylactic lymph node dissection may not be necessary for a discriminant score greater than 2, whereas extended lymphadenectomy would be recommended for a score less than -1.

Adenocarcinoma↗
PubMed1994

Roles of histological findings and serum AFP levels in the prognosis of AFP-producing gastric cancers.

We investigated the roles of histological findings and serum AFP levels in the prognosis of gastric cancers which produce AFP. We considered the typical features of such gastric cancers to be the medullary growth of undifferentiated cancer cells with clear, or slightly eosinophilic, abundant cytoplasm and pleomorphic large round nuclei, forming either papillary clear carcinomas or hepatoid carcinomas. Seventeen patients with AFP-producing gastric cancers were observed in the period, 1979-1991. They were divided into two groups: those with (n 5) and those without (n 12) the typical histological features mentioned above. Their clinicopathological findings and prognoses were compared. Both groups showed a male dominance, gross Borrmann's type 2 or 3 appearances, diagnoses made at an advanced stage and metastatic involvements of the liver. The patients with the typical histological features showed a significantly higher AFP serum level and a significantly shorter survival. The patients who lacked the typical findings, and with serum AFP levels > or = 100 ng/ml, had poorer prognoses, while those lacking the typical histological features, and serum AFP levels < 100 ng/ml had better prognoses. The combination of histological findings and serum AFP level appeared to be useful in predicting the prognosis of AFP-producing gastric cancers. Intensive adjuvant therapy, e.g., chemotherapy administered via hepatic arterial infusion, may be indicated for patients at a high risk of recurrence following curative surgery.

Carcinoma, Papillary↗
PubMed1993

Proposal of a risk score for recurrence in patients with curatively resected gastric cancer.

In this study, 168 patients who underwent curative resection for gastric cancer with prognostic serosal invasion [ps(+)] and 150 without prognostic serosal invasion [ps(-)] were analyzed separately to determine the prognostic importance of clinicopathological factors, and identify which patients were at high risk of recurrence. A multivariate analysis of survival time using Cox's proportional hazard model revealed the important prognostic factors to be: Lymph node involvement, the classification of gross appearance, macroscopic serosal invasion, and interstitial connective tissue in the ps(+) group; and lymph node involvement, macroscopic serosal invasion, and venous invasion in the ps(-) group. We proposed a risk score of recurrence based on the results of a further multivariate analysis called Hayashi's Quantification Analysis II, in which recurrence was chosen as an objective variable and the above prognostic factors were chosen as explanatory variables. Eighty-four percent of the patients with a score of 0 or higher in the ps(+) group and 83% of those with a score of +6 or higher in the ps(-) group showed recurrence. Thus, we believe that this score is useful for identifying those patients at high risk of recurrence, who should receive intensive chemotherapy even after curative resection.

Female↗
PubMed1993

Comparison of the prognostic significance between the number of metastatic lymph nodes and nodal stage based on their location in patients with gastric cancer.

PURPOSE: To determine which is the better prognostic determinant in gastric cancer: number of positive metastatic lymph nodes or current nodal stage. PATIENTS AND METHODS: Seven hundred seventy-seven patients who underwent potentially curative resections for gastric cancer were divided into three groups according to the depth of invasion. The influence of the number of positive nodes on their survival rate was analyzed. A multivariate analysis by the Cox proportional hazards model was used to determine independent prognostic factors. RESULTS: A decreased survival rate was associated with an increased number of positive nodes in all of the subjects and in each of the three groups. Patients with one to three positive nodes had as good a prognosis as those without nodal involvement when each of the three groups was analyzed separately. Using a multivariate analysis in the patients with four or more positive nodes, we found that the number of positive nodes was the most important prognostic determinant (P < .0001), followed by the depth of invasion (P < .02), and that the nodal stage was not significantly prognostic. Further multivariate analysis in the patients with one to three positive nodes showed that nodal stage and number of positive nodes were not significantly prognostic. CONCLUSION: The number of metastatic nodes should be adopted for classification of nodal stage in gastric cancer.

Adenocarcinoma↗
PubMed1992

Intravascular circulation and distribution of human 51Cr-DBBF stroma-free hemoglobin.

Male B6C3HF1 mice were infused with 51Cr-labeled DBBF (bis 3,5-dibromosalicyl fumarate) crosslinked stroma-free hemoglobin (SFH). The intravascular halftime (T50) of the DBBF-SFH, determined from plasma hemoglobin levels, was 0.5 hours in the first 10 minutes and 4.3 hours during the next 50 minutes. At 24 hours, less than 5% of the DBBF-SFH remained. Elution of 51Cr was reflected in a lower T50 determined from the radioactivity levels: during the first 10 minutes the T50 was 0.3 hours; in the next 50 minutes it was 1 hour. The radioactivity sequestered in each organ in the first hour following DBBF-SFH infusion was as follows: 11.2% of the infused radioactivity was in the skin, 11.4% in muscle, 9.1% in the skeleton, and 5% in the liver. After 24 hours, the percentages in skin, muscle, skeleton and liver were 15.4, 10.3, 16.6 and 6.7% respectively. The percentage of infused radioactivity in the gastrointestinal tract and kidney at 1 hour and 24 hours ranged from 3.5 to 5.5%. Less than 0.4% was found in the spleen and lung. At 24 hours, 25% of the radioactivity was recovered in urine and 3% in feces.

Animals↗
PubMed1992

[Acid-base disturbances in surgical operation].

Metabolic acidosis immediately after surgical operation is followed by metabolic alkalosis. Hormonal change by surgical stress and anaerobic glucolysis due to tissue ischemia cause initial lactic acidosis. Later alkalosis may be caused by secondary aldosteronism and bicarbonate production from lactate and citrate supplied by massive infusion and transfusion. Postoperative complications, such as respiratory insufficiency, renal failure and hypovolemic or septic shock, cause acidosis. In the gastrointestinal surgery, acidosis can be caused by starvation and loss of bicarbonate contained in bile, pancreatic juice or intestinal fluid, and alkalosis can be caused by loss of HCl in gastric juice. Severe acidosis can be caused by extracorporeal circulation, hypothermia, low output syndrome or declamping shock in cardioaortic surgery.

Acid-Base Imbalance↗
PubMed1991

[Effects of syngeneic preserved blood cells on metastatic growth of the Lewis lung carcinoma].

Each of B6C3HF1 mice was infused with stored syngeneic blood cells, fresh syngeneic blood cells, or saline, and then was injected intravenously with 1 x 10(6) Lewis lung carcinoma cells. Survival rate of each group declined in order of the saline group, the fresh-cell group, and the stored-cell group with a significant difference between all paired groups (p less than 0.001). When the number of metastases and 125I-Iododeoxyuridine uptake in the lungs and livers were compared between these groups, there were significant differences with greater number and uptake in the stored-cell group than the fresh-cell group or the saline group on day 15 through 17, and greater in the fresh-cell group than the saline group on day 23 and 24. In the second experiment, each mouse was inoculated subcutaneously with 1 x 10(5) tumor cells. Twenty-one days later, the subcutaneous tumors were removed, and the mice were infused with blood cells or saline immediately. The number of lung metastases of the stored-cell group was significantly larger than that of the fresh-cell group or the saline group on 9 and 11 days following tumor removal. In conclusion, the transfusion of the preserved syngeneic blood cells was considered to enhance both artificial and spontaneous metastasis of the Lewis lung carcinoma.

Animals↗
PubMed1988

[A study of the effects of fresh frozen plasma to improve host defense against bacterial infection and levels of coagulation factors after hepatectomy].

Intraperitoneal infection and massive bleeding after hepatectomy often lead to liver failure. A possible cause of these complications may be the debasement of coagulation factors and opsonins in plasma after hepatectomy. The effects of fresh frozen plasma (FFP) to prevent these complications were investigated. 1) In the patients administered with more than 10 units/day of FFP after major hepatectomy, postoperative plasma opsonic activity was higher and the frequency of the intraperitoneal infection was lower than in the patients administered with smaller volume. In the former group, the activity of coagulation factors tended to increase postoperatively except for factor VII. But even the activity of factor VII was above critical level, and actually postoperative bleeding caused by coagulative insufficiency was not observed. 2) In the 70%-hepatectomized dogs, disappearance curve of intravenously injected Escherichia coli was biexponential. So two compartment model composed of circulating blood and phagocytic system was applied and velocity constants of the each phases of sequestration, reflux, and ingestion were calculated. The administration of FFP and opsonization of bacteria by normal plasma did not influence the phases of sequestration and reflux, but significantly accelerated the ingestion phase. The administration of FFP also increased survival rate after bacterial injection. These results suggest that FFP is effective on improving host defense against bacterial infection.

Aged↗
PubMedDate not supplied

Correlation between telomerase activity and DNA ploidy in gastric cancer.

Telomerase has been reported to be activated in most immortal cells and human cancers. In the present study, we assessed the correlation between telomerase activity and cellular DNA ploidy level in gastric cancer. Telomerase activity was determined semiquantitatively using the telomeric repeat amplification protocol assay, a polymerase-chain-reaction-based assay, in surgical specimens of primary tumors obtained from 36 patients with gastric cancer. No correlation was observed between telomerase activity and the proliferating cell nuclear antigen labeling index. In contrast, a positive linear correlation was observed between telomerase activity and the DNA index (r = 0.59; p < 0.01). Tumor cells with aneuploid patterns showed higher telomerase activity than those with diploid patterns (27.6+/-5.8 vs. 5.8+/-1.1%; p < 0.01). Telomerase activity of tumors with liver metastases was significantly higher than activity of those without metastases (34.5+/-16.6 vs. 11.8+/-2.4; p < 0.05). There was a trend toward a lower survival rate in 9 patients with a telomerase activity of 20% or higher compared to 27 patients with telomerase activity lower than 20%. These results suggest that the telomerase activity of gastric cancer tissue may reflect the malignant potential of the tumor.

Adult↗