Biomedical subjects

Y Maehara

Publications and source records attributed to Y Maehara.

At least 235 records · Page 13Linked to original sources

PubMed1992

Lower survival rate for patients with carcinoma of the stomach of Borrmann type IV after gastric resection.

Between 1965 and 1985, 194 of 1,113 patients (17.4 percent) with advanced carcinoma of the stomach who underwent gastric resection had Borrmann type IV carcinoma of the stomach, a macroscopically evident and diffusely spreading tumor. These patients tended to be younger and female and to have larger tumors that involved the entire stomach, as compared with patients with other types of carcinomas. Tissues were commonly undifferentiated, serosal invasion was prominent with infiltrative growth and high rates of metastasis to the lymph nodes and peritoneal dissemination were evident. In most instances, the disease was advanced; therefore, total gastrectomy was performed upon 82.0 percent of the patients and a palliative resection was done in 64.4 percent. The survival rate was lower than for patients with carcinoma of the stomach of other types (p less than 0.01). A multivariate analysis indicated that curative resection is an independent favorable prognostic event, while other factors are dependent covariates. Early detection of this carcinoma is crucial to extend survival time of patients with Borrmann type IV carcinoma of the stomach. Aggressive postoperative chemotherapy should be considered when a noncurative resection is done.

Female↗

PubMed1991

DNA ploidy is associated with growth potential in gastric carcinoma.

To correlate growth potential with DNA ploidy 109 patients with early gastric carcinoma and 132 patients with advanced gastric carcinoma were studied. Early gastric carcinomas were classified by growth potential into the small mucosal type, the superficially spreading (super) type, or the expansively penetrating (Pen A)/infiltratively penetrating (Pen B) types. Advanced gastric carcinomas were classified into funnel, column, or mountain types, each of which was divided further into expanding and infiltrative types. Cell nuclear DNA content was measured by microspectrophotometric study and classified as either low or high ploidy according to the degree of dispersion on the DNA histogram. Super type early and funnel type advanced carcinomas, characterized by superficially spreading growth, were more likely to have low DNA ploidy. In contrast, Pen A type early and column-expanding type advanced carcinomas, characterized by expansively penetrating growth, were more likely to have high DNA ploidy.

DNA, Neoplasm↗

PubMed1991

Helix pomatia agglutinin binding activity is a predictor of survival time for patients with gastric carcinoma.

The authors used helix pomatia agglutinin (HPA) staining to examine 163 primary gastric carcinoma isolates, using the avidin-biotin-peroxidase complex method. The positive HPA staining rate was 59% (96/163) for the primary tumors, and the positive staining correlated well (with statistical significance) with tumor enlargement, penetration, lymphatic invasion, and metastasis (P less than 0.01), and with infiltrative spread (P less than 0.05). Patients with gastric cancer showing positive HPA staining had a lower survival rate (P less than 0.001), particularly when the cancer cells were present on the serosal surface. Careful follow-up and intensive postoperative therapy are required for patients with an HPA-positive advanced gastric carcinoma.

Acetylgalactosamine↗

PubMed1991

Nuclear DNA content, tumor cell aggregation, and metastatic events in patients with poorly differentiated adenocarcinoma of the stomach.

Data on 100 patients who had undergone resection for poorly differentiated adenocarcinoma of the stomach with serosal invasion were examined to assess the prognostic significance of the DNA distribution pattern in relation to the histologic tumor cell aggregation pattern. DNA distribution patterns were classified into low and high ploidies and tumor cell aggregation patterns were classified into free-cell, small nest, and large nest types. The rates of high ploidy in the free-cell, small nest, and large nest types were 23.1%, 48.0%, and 66.7%, respectively, with a significant increase according to the degree of aggregation. The high ploidy group and large nest type had a higher incidence of lymphogenous and hematogenous metastasis than the low ploidy group and free-cell type, respectively. DNA ploidy had no prognostic value for the free-cell type of tumor, but differences in prognosis and the incidence of metastasis between the DNA ploidies were evident in the nest-forming type. Aneuploid tumors consisting of a poorly differentiated adenocarcinoma were those with nest formation, from the standpoint of histologic structure and metastatic behavior. The DNA analysis of poorly differentiated adenocarcinomas was of prognostic value, especially in the nest-forming type.

Adenocarcinoma↗

PubMed1991

Clinicopathologic features and prognostic significance of duodenal invasion in patients with distal gastric carcinoma.

Clinicopathologic features and prognostic significance of duodenal invasion were studied in a retrospective study on 593 patients who underwent gastrectomy for adenocarcinoma in the antrum. The patients were grouped into three, according to the histologic extent of duodenal invasion: Group A (80 patients), obvious invasion beyond the pyloric ring; Group B (61 patients), invasion up to the pyloric ring; and Group C (452 patients), no evidence of duodenal invasion. Five-year survival rates in Groups A, B, and C were 7.9%, 31.6%, and 57.6%, respectively (P less than 0.001). Cox's regression analysis showed that duodenal invasion is an independent prognostic factor in cases of a gastric antrum carcinoma. Gastric cancer with duodenal invasion (Groups A and B) most often was infiltrative and the incidence of serosal invasion, lymphatic and vascular invasion, and lymph node metastasis was high. Duodenal invasion was direct through submucosal or subserosal layers or through submucosal lymphatics.

Adenocarcinoma↗

PubMed1991

Predictive value of Ki-67 and argyrophilic nucleolar organizer region staining for lymph node metastasis in gastric cancer.

Proliferative activities in 91 primary gastric carcinomas and 36 corresponding metastatic perigastric lymph nodes were investigated using Ki-67 labeling percentage and an argyrophilic nucleolar organizer region (AgNOR) count. Tumors with a high proliferative activity often metastasized to lymph nodes, and the proliferative activities of the primary lesion and the perigastric lymph node metastases were similar. A significant correlation was recognized between the Ki-67 labeling percentage and the AgNOR count (r = 0.744; P less than 0.001). The Ki-67 labeling percentage and AgNOR count proved to be useful predictors of nodal metastasis regardless of tumor size, depth of invasion, and histological type. Even when tumors are smaller (less than 7 cm) or the stage of the disease is early (pT1, 2), the formation of metastasis increased with an increased Ki-67 labeling percentage or AgNOR count. The combination analysis of depth of invasion with Ki-67 labeling percentage or AgNOR count gives a more precise prediction of nodal metastasis, compared with histological analysis alone.

Antibodies, Monoclonal↗

PubMed1991

Splenectomy does not correlate with length of survival in patients undergoing curative total gastrectomy for gastric carcinoma. Univariate and multivariate analyses.

The relationship between splenectomy and survival time after curative total gastrectomy for advanced gastric cancer was examined by reviewing retrospectively data on 252 patients treated in our clinics between 1965 and 1985. One hundred three patients (40.9%) did not undergo splenectomy and 149 (59.1%) did. In patients subjected to splenectomy, advanced stages of the malignancy were more frequent and metastasis was noticed in 8.1% of splenic hilar lymph nodes and in 10.1% of the lymph nodes associated with the splenic artery. A univariate analysis revealed that the survival time of patients with splenectomy was significantly less than those for whom splenectomy was not done (P less than 0.05). In a subgroup of our patients stratified to adjust for the stage of disease, there was no significant difference between the survival rates. Subsequently, multivariate analysis using the Cox regression analysis adjusted for sex, age, and other covariates indicated that serosa invasion, lymph node metastasis, and tumor size were the most important prognostic factors, and there was no correlation whatever with splenectomy. Our findings rule out any relationship between splenectomy and length of survival time in patients undergoing curative total gastrectomy for advanced gastric cancer.

Carcinoma↗

PubMed1991

Clinical management of gastric cancer and concomitant esophagogastric varices.

We report the late results of treatment of 13 consecutive patients with gastric cancer and concomitant esophagogastric varices. Of seven good-risk patients classified as Child's class A or B, gastrectomy together with selective shunt operation was performed in two, total gastrectomy with splenectomy in three, and distal partial gastrectomy with paraesophageal devascularization without splenectomy in one. The remaining patient with early gastric cancer underwent distal partial gastrectomy following repeated endoscopic injection sclerotherapy (EIS) for treatment of the esophageal varices. Although the majority of patients who underwent surgical repair of varices (i.e., shunt, splenectomy, or devascularization) died, total gastrectomy with splenectomy was the only procedure that led to control of the esophageal varices. Since partial gastrectomy combined with EIS limits the morbidity and mortality of an extensive resection and at the same time controls esophageal variceal bleeding, it is probably the procedure of choice for patients with a carcinoma in the lower two-thirds of the stomach. Concerning non-surgical cases, two patients were effectively treated using laser endoscopy and EIS, without the occurrence of variceal bleeding. The remaining four patients, given chemotherapy or irradiation for treatment of gastric carcinoma, died within 4 months with variceal bleeding or liver failure. For the poor-risk patients with evidence of severe liver dysfunction, laser treatment and EIS would be the treatment of choice.

Aged↗

PubMed1991

Comparison of R1 and R2 gastrectomy for gastric cancer in patients over 80 years of age.

To evaluate the benefit of R2 gastrectomy for gastric cancer in Japanese patients over 80 years of age, data on 93 patients who underwent gastrectomy between 1967 and 1989 were collected retrospectively from charts filed in the Kyushu University Hospital and two affiliated national hospitals. Of 93 patients, 62 had a localized tumor without evidence of metastatic spread. These 62 patients were classified into two groups according to the procedures performed: 35 underwent R1 gastrectomy and 27, R2 gastrectomy. The clinical and pathological characteristics of the patients in the two groups were comparable at the time of surgery, except that the group who underwent R1 gastrectomy was older. R2 gastrectomy involved a significantly longer operation time (P less than 0.01) and greater intraoperative blood loss (P less than 0.05) when compared to R1 gastrectomy, but no patient undergoing this extensive surgery died. The difference in the morbidity rate between the two groups was not statistically significant. The 5-year survival rate was 55.8% in the R1 group and 65.4% in the R2 group. When gastric cancer invaded the serosa and/or secondary nodes, a substantial increase in survival time was gained with R2 gastrectomy when compared to an R1 operation. These findings suggest that an R2 gastrectomy is feasible, even for patients over 80 years, but is indicated mainly when the carcinoma had invaded the serosa and/or secondary nodes and the patients are at good risk for major surgery.

Aged↗

PubMed1991

Clinical features of the differentiated and undifferentiated types of advanced gastric carcinoma: univariate and multivariate analyses.

This study was done to define clinical features for the different pathological types of advanced gastric carcinoma. One thousand one hundred three patients were identified and classified into two groups: 479 patients (43.4%) had a differentiated adenocarcinoma and 624 patients (56.6%) had an undifferentiated adenocarcinoma. Patients with the undifferentiated type were more likely to have large invasive tumors and a higher incidence of peritoneal dissemination. Conversely, the patients with the differentiated type were more likely to have a liver metastasis. Multivariate analysis, using Cox' proportional hazard model adjusted for sex, age, and other factors, suggested that tumor size was one of the seven most independent prognostic factors in patients with the undifferentiated type (relative risk = 1.01), but this parameter lost prognostic value in patients with the differentiated type. With regard to correlation between survival time and tumor size, the larger the tumor (over 10 cm), the shorter the survival time of patients with the undifferentiated type, as compared to findings in patients with the differentiated type (P less than 0.01). Thus, differences in clinical characteristics, including characteristics in the individual patients, extent of tumor, distant metastasis, prognostic factors, and prognosis correlate with the histopathological type of gastric carcinoma.

Adenocarcinoma↗

PubMed1991

Increased cytotoxicity of low-dose, long-duration exposure to 5-fluorouracil of V-79 cells with hyperthermia.

We examined the cytotoxic effects of combined low dose and long exposure to 5-fluorouracil (5-FU) and hyperthermia on Chinese hamster V-79 cells with reference to timing and sequence of administration. The survival rate following hyperthermia at 42 degrees C for 2 h alone was 95.4%, and that after exposure to 1.0 micrograms/ml/5-FU alone for 48 hours, 94.2%. With respect to the combination of 5-FU and heat, the survival rate of cells exposed to hyperthermia at 42 degrees C for 2 h followed by 1.0 micrograms/ml 5-FU treatment for 48 h followed by hyperthermia led to a survival rate of 10%. Flow cytometric analysis of V-79 cells after exposure to 1.0 micrograms/ml 5-FU for 48 h revealed an accumulation of cells in the S-phase; the percentage of S-phase exponential growing cells was 65% and the plateau phase was 38%. The former were more sensitive to heat than the latter cells according to the MTT assay. V-79 cells pretreated with 5-FU were more sensitive to hyperthermia than were those not pretreated with 5-FU. Therefore, when 5-FU plus heat is to be used to treat a patient with a malignancy, the sequence of 5-FU followed by hyperthermia may be more effective than the reverse.

Animals↗

PubMed1991

Lower survival rate for patients under 30 years of age and surgically treated for gastric carcinoma.

We analysed data on 38 patients with gastric cancer aged 30 years and younger who were surgically treated in the Department of Surgery II, Kyushu University Hospital, between 1965 to 1985. These younger patients comprised 2.6% of the total 1,470 patients treated for gastric cancer during this 21-year period. The durations and the kinds of symptoms in the preoperative period varied with the patient. In patients under 30 years of age, the female patients predominated, and in addition, undifferentiated lesions were more common than the differentiated type, tumours were larger, serosal invasion was more prominent, lymphatic involvement was more common, tumours showed infiltrative growth and the rate of peritoneal dissemination was higher. Consequently the survival rates for these younger patients were poor. Detection at an early stage of the disease is mandatory if the survival rates of younger patients with gastric cancer are to improve.

Adult↗

PubMed1991

Death due to recurrence following curative resection of early gastric cancer depends on age of the patient.

This study was done to define the relationship between age at the time of surgery and the prognosis after curative resection for patients with an early gastric cancer. Three hundred and eighty-two patients were identified and 25 patients died of tumour recurrence. Overall, the cumulative survival rate was 94.9% at 5 years and 92.4% at 10 years. Patients with a recurrence of the gastric cancer tended to be older, were more likely to have large differentiated type of tumour and lymph node metastases were often present. Stratified into age-classified groups, the survival rate decreased with increase of age (for patients under age 34 years, 35 to 44, 45 to 54, 55 to 64, 65 to 74, over age 75 years, the 5-year survival rates were 100.0, 97.7, 97.6, 94.2, 94.1 and 84.4 (%]. Of the 25 patients with a tumour recurrence and who died, the survival time of 18 patients over age 55 years was significantly shorter than that of seven patients under age 54 years (median, 1.7 vs 5.6 years, P less than 0.05). The multivariate analysis showed that, over and above the differentiated type of tumour (P less than 0.01) and the presence of lymph node metastases (P less than 0.01), age was one of the prognostic factors (P less than 0.05). We conclude that age at the time of primary surgery is a significant factor in patients with an early gastric cancer.

Adult↗

PubMed1991

1-Hexylcarbamoyl-5-fluorouracil alters the expression of heat shock protein in HeLa cells.

We determined the effect of 1-hexylcarbamoyl-5-fluorouracil (HCFU), a masked compound of 5-fluorouracil, on the expression of heat shock protein (HSP) in heat-treated HeLa cells. We used a monoclonal anti-72-kDa heat shock protein antibody. At 37 degrees C, HSP was predominant in the cytoplasm of cells and heating to 43 degrees C for 30 min increased the synthesis of HSP in the nucleus. When HeLa cells were treated with heat and HCFU, at a concentration which showed evidence of synergy, nuclear staining of the cells decreased. Thus, the altered expression of HSP by HCFU is related to a synergism between heat and HCFU.

Cells, Cultured↗

PubMed1991

Dipyridamole combination chemotherapy can be used safely in treating gastric cancer patients.

The feasibility of a combined chemotherapy using dipyridamole (DP) with adriamycin (ADM) and 5-fluorouracil (5-FU) was investigated. First, the chemosensitivity of gastric cancer tissues was determined by the succinate dehydrogenase inhibition test, which showed sensitivity to ADM and 5-FU is increased by DP. Next, a clinical trial of combined therapy of DP, ADM and 5-FU, as a post-operative adjuvant chemotherapy for gastric cancer patients, was performed. DP (50 mg) was given as a 1-h i.v. infusion, and ADM (20 mg) was given as a single i.v. injection. This treatment was started on post-operative day 10, and was repeated every 2 weeks. Simultaneously with these treatments, DP (300 mg) and 5-FU (150 mg) were administered post-operatively daily. A total of 63 courses of therapy in nine patients were performed. The adverse effects related to the DP infusion were flushing, headache, nausea and upper abdominal discomfort, all of a low grade. DP did not appear to alter the toxicity of ADM and 5-FU, and no severe adverse effect was noted for this combination therapy. The pharmacokinetics of DP were also investigated in five patients. The mean plasma concentration of DP increased 4.41 micrograms/ml and remained above 0.25 microgram/ml for over 6 h. This combination chemotherapy appears to be safe and may be useful clinically in treating cancer.

Adult↗

PubMed1991

The microtiter SDI test is more advantageous than the SDI test for assessing the chemosensitivity of human tumor cells.

The in vitro succinate dehydrogenase inhibition (SDI) test was adapted to be used with microtiter plates and this microtiter SDI (mSDI) test was evaluated for clinical use of chemosensitivity testing, as compared to findings with the SDI test. The optimal conditions of the mSDI test were determined: (1) 2-5 x 10(4) cells/well; (2) enzymatic disaggregation of solid tumors with the use of a mixture of 0.2% pronase, 0.25% collagenase, 0.1% DNase for 20 min at 37 degrees C; (3) addition of 10 mM sodium succinate in the colorimetric reaction; and (4) use of dimethyl sulfoxide (DMSO) as a solvent for extraction of formazan product. Good correlations were observed between the mSDI and the SDI tests when S-180 cells (r = 0.890-0.996) or 16 human fresh tumor cells (r = 0.731-0.999) were exposed to six anti-cancer drugs (carboquone, adriamycin, mitomycin C, aclacinomycin A, cisplatin, 5-fluorouracil). Thus, the mSDI test facilitates testing of a large number of drugs with minimal amounts of specimens, and is expected to replace the SDI test for chemosensitivity testing of clinical tumor cells.

Animals↗

PubMed1991

A protein-bound polysaccharide immunomodulator, PSK, does not suppress the conversion from 1-(2-tetrahydrofuryl)-5-fluorouracil to 5-fluorouracil in patients with gastric cancer.

Effects of the immunomodulator PSK on the metabolism of 1-(2-tetrahydrofuryl)-5-fluorouracil (tegafur) to 5-fluorouracil (5-FU) were examined in 10 patients with advanced gastric cancer and who had undergone curative resection. PSK is a protein-bound preparation, extracted from Coriolus versicolor and belongs to Basidiomycetes. The 5-FU concentration in the plasma was 0.024 micrograms/ml at 15 min after the intravenous injection of 400 mg of tegafur and the area under the curve of 5-FU was 0.58 micrograms.h/ml. Following administration of PSK, 3 g/day for 8-14 months, there was no change in the plasma level of 5-FU, in any patient. As the clinical dose of PSK had no apparent influence on the metabolism of tegafur to 5-FU, the combination of PSK and tegafur can be prescribed to treat patients with advanced gastric cancer.

Antibiotics, Antineoplastic↗

PubMed1991

Cisplatin plus continuous infusion of 5-fluorouracil for 5 days effective for patients with advanced gastric cancer.

Seventeen consecutively treated patients with advanced gastric cancer were prescribed every 3 weeks intravenous cisplatin (20 mg/m2/day) and a continuous infusion of 5-fluorouracil (5-FU) (750 mg/m2/day) for 5 days. Twelve (71%) patients had been treated previously with other anticancer drugs. Seven (42%) patients showed a partial response and these responses persisted for over 4.4 months. Stabilization of the disease occurred in eight (47%) patients, and in two (12%) the disease progressed. At the time of analysis, mean survival of the responders was 8.2 months, while that of non-responders was 5.0 months. The toxicities were within acceptable limits and only a few had a grade III toxicity. This combined administration of cisplatin and 5-FU for 5 days is safe and effective for patients with advanced gastric cancer.

Adult↗