Hidetaka Masuda

Serum CEA levels facilitate detection of recurrences of cancer in patients after gastrectomy

In an attempt to assess the usefulness of carcinoembryonic antigen (CEA) for predicting the progression of gastric cancer, CEA productivity was evaluated according to serum CEA levels, at the time of recurrence or relapse. In cases of a recurrence, abnormal CEA levels were observed in 14 of 17 (82.4 per cent) with differentiated carcinoma and in 9 of 21 (42.9 per cent) with undifferentiated carcinoma. Preoperative abnormal CEA levels were observed in only 6 of 41 patients (14.6 per cent). A median lead time of manifestation of recurrence was 5 months. In those with relapse, 9 of 11 (81.8 per cent) patients with differentiated carcinoma and 13 of 18 (72.2 per cent) with an undifferentiated carcinoma had abnormal CEA levels. Preoperative abnormal CEA levels were observed in 24 of these 89 patients (27.0 per cent). Postoperative monitoring of CEA seems to be useful for early recognition of gastric cancer progression, irrespective of the preoperative CEA levels.

Late results of postoperative long-term cancer chemotherapy for the gastric cancer patients subjected to curative resection

Postoperative long-term cancer chemotherapy (PLCC) with a combination of Mitomycin-C (MMC), FT-207 and PSK (an immunostimulant) was prescribed for gastric cancer patients subjected to curative resection. The 5 year survival rates for patients with stage III and stage IV cancer were 58.3 per cent and 50.0 per cent in the PLCC groups, 48.0 per cent and 15.4 per cent in MMC groups, and 46.3 per cent and 13.3 per cent in no chemotherapy groups, respectively. In stage IV, the survival rate in PLCC group was significantly higher than that in MMC or no chemotherapy group (p<0.05). In the PLCC group, there was a tendency toward a dose-dependent effect in each group, and 5 year survival rate of stage III group administered over 60 mg of MMC, 60 g of FT-207 and 270 g of PSK was 70 per cent, such being remarkably higher than 46.3 per cent in those given no chemotherapy (p<0.07). There was no drug related death and only a slight leukopenia and hepatotoxicity occurred in some patients.

Laparoscopy-assisted distal gastrectomy for early gastric cancer with versus without prophylactic drainage.

PurposeLittle has been reported on routine prophylactic abdominal drainage after gastrectomy, especially after laparoscopy-assisted distal gastrectomy (LADG). We conducted this retrospective study on patients undergoing LADG to evaluate the benefit of routine drainage in LADG procedures.MethodsThe subjects were 21 patients who underwent surgery for early gastric cancer (EGC) between January 2004 and March 2008. They comprised 10 who underwent LADG with drainage before January 2006 and 11 who underwent LADG without drainage after February 2006. We compared patient and tumor characteristics, operative results, and postoperative outcomes between the groups.ResultsThe no-drain group of patients were able to eat their first meal significantly sooner than the drain group patients (P < 0.01); however, the time to start ambulating, passing flatus, and drinking was similar in the two groups. There were no significant differences between the groups in the postoperative complication rate or the postoperative hospital stay. The drain did not seem to add benefit, and no complications due to the lack of drain placement were noted in the no-drain group.ConclusionRoutine prophylactic abdominal drainage after LADG for EGC may not be necessary.

5-Fluorouracil's cytotoxicity is enhanced both in vitro and in vivo by concomitant treatment with hyperthermia and dipyridamole.

SummaryWe obtained evidence that the cytotoxic effect of 5-fluorouracil (5-FU) is augmented when the drug is given in combination with hyperthermia (HYP) and dipyridamole (DP). Nontoxic levels of DP enhanced the combined cytotoxicity of 5-FU and HYP against B16 melanoma and human tumor cells in vitro as measured by the succinate dehydrogenase inhibition (SDI) test. Growth of B16 melanoma that had been subcutaneously implanted into the feet of C57 BL mice was inhibited by treatment with the combinations of 5-FU and HYP, of 5-FU and DP, and of 5-FU, HYP and DP as compared with the administration of 5-FU alone. Treatment with HYP plus DP did not alter the body weight of mice that received 5-FU. The administration of DP plus HYP seemed to render the tumor cells more sensitive to 5-FU. The combination of 5-FU, HYP and DP shows promise for the treatment of patients suffering from malignant disease.

Induction of chromosomal aberrations and 8-azaguanine-resistant mutations by aryldialkyltriazenes in cultured mammalian cells.

Inducibility of chromosomal aberrations, cell survival, and mutation to 8-azaguanine (8AG) resistance in cultured V79 cells by 1-phenyl-3,3-dimethyltriazene (PDMT), 1-phenyl-3,3-diethyltriazene (PDET), and 1-(pyridyl-3)-3,3-diethyltriazene (PyDET) were examined with or without metabolic activation. Chromosomal aberrations were induced in a dose-dependent manner by all 3 triazenes in a direct treatment for 24 h. Chromosomal aberrations were also induced by PDMT with metabolic activation system for 3 h, and little differences in the incidences were observed compared with those obtained by a direct treatment. All 3 triazenes were slightly mutagenic in a direct treatment for 24 h. In metabolic activation experiments, however, PDMT and PyDET were highly mutagenic. The mutagenicity, when compared with the cytotoxicity, was significantly higher in a metabolic activation system than in a direct treatment.

Bidirectional effects of splenectomy on the growth of syngeneic tumor in mice.

The effects of splenectomy on tumor growth following inoculation with a relatively large number of cells (1×107) and a smaller number of cells (5×105) of Meth I tumor were studied. When 1×107 tumor cells were inoculated, tumor growth in splenectomized mice was depressed, while tumor in sham-operated mice grew progressively. On the contrary, when 5×105 tumor cells were inoculated, the tumor take was lower in sham-operated than in splenectomized mice. The spleen cells from mice inoculated with either a large or small number of tumor cells, showed an equally potent cytotoxic activity, but no detectable suppressor cell activity. On the other hand, the activity of immunosuppressive factor was detected in sera from mice inoculated with 1×107 tumor cells, but not in those given 5×105 cells. The effect of splenectomy on tumor growth is, thus, bidirectional, depending on the dose of tumor cells inoculated.

Hydroxyurea inhibits degradation of internalized epidermal growth factor in HeLa cells.

Abstract Because epidermal growth factor stimulates DNA synthesis in cultured cells, five inhibitors of DNA synthesis were tested in HeLa cells to see whether the inhibition of DNA synthesis has any effect on the metabolism of the growth factor. Among these, only hydroxyurea inhibited the degradation of 125 I-labeled epidermal growth factor strongly. The reversal of hydroxyurea-induced inhibition of DNA synthesis by deoxyribonucleosides did not result in a recovery from the inhibition of the degradation. From these findings, it might be concluded that the inhibitory effect of hydroxyurea on the degradation is distinct from that on DNA synthesis.

Combination chemotherapy enhances survival of patients with unresectable gastric cancer.

Of 177 Japanese patients with a gastric cancer which could not be resected and seen at our institution during the period from 1964 to 1979, 153 were investigated with regard to the efficacy of anticancer agents, in terms of prolongation of life. The average survival time was 23 weeks in the combination chemotherapy group (57 cases), 17 weeks in the single drug chemotherapy group (42 cases) and 13 weeks in no chemotherapy group (54 cases). Three and 6 month survival rates in the overall patients were 57.1 per cent and 16.7 per cent for single drug chemotherapy group, and 37.0 per cent and 11.1 per cent for no chemotherapy group, while in the combination chemotherapy group, the rates were higher at 64.9 per cent and 29.8 per cent, respectively (combination chemotherapyvs. no chemotherapy group, p<0.05). In patients with peritoneal dissemination, hepatic metastasis and carcinomatous ascites, there was a significant difference in survival rates between those prescribed combination chemotherapy and those given no chemotherapy (p<0.05). Of 57 in the combination chemotherapy group, 6 and 9 month survival rates were 45.5 per cent and 22.7 per cent in the postoperative long-term cancer chemotherapy (PLCC) group (22 cases), such being higher than other combination chemotherapy group (35 cases), 22.9 per cent and 11.4 per cent, respectively. There was a significant difference in the survival rates between the two groups (p<0.05).