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N Hamajima

Publications and source records attributed to N Hamajima.

At least 145 records · Page 8Linked to original sources
PubMed1989

Clinical value of long-term maintenance chemotherapy in 5-year survivors of acute leukemia.

We investigated whether long-term follow-up of 5-year or longer survivors of acute leukemia might provide some information concerning cure-oriented chemotherapeutic strategy. By sending a questionnaire form to major medical institutions throughout the country, data of 2202 5-year or longer survivors of acute leukemia was obtained as of 30 June 1988. There were 1607 children and 595 adults. In order to investigate the data further, they were divided into four periods according to the year of diagnosis: before 1969, 1970-1974, 1975-1979 and 1980-April 1983. As regards remission induction regimens, vincristine plus prednisolone (VP) was the most popular in childhood acute lymphoblastic leukemia (ALL) throughout these four periods. In adult acute non-lymphoblastic leukemia (ANLL), daunomycin (DM), cytosine arabinoside (ard-C), 6-mercaptopurine (6MP), prednisolone (STH) (DCMP) or behenoyl ara-C, DM, 6-MP, STH (BH-AC.DMP) was the most popular since the latter half of the 1970s. Both in childhood ANLL and adult ALL, there was no predominant regimen whatsoever. In an analysis of survival curves for the above four periods, each survival plateau for childhood ALL rose over time with statistical significance, reaching over 90% in the 1980s, whereas those for adult ANLL were not so, suggesting that newer ANLL regimens in the 1980s did not play a successful role in cure-oriented therapy. Whether duration of post-remission chemotherapy could be a prognostic factor for these survivors was studied by dividing the duration as follows: less than one year, 1-2, 2-3, 3-5 and more than 5 years. A therapeutic gain, with a cure rate of over 90%, was observed in childhood ALL patients treated with chemotherapy for 5 years or longer. In adult ANLL patients, results were similar with chemotherapy groups of both less than one year and 5 years or longer. This suggests that risk-adapted therapy is an optimal strategy for cure of adult ANLL as well as childhood ALL.

Antineoplastic Agents↗
PubMed1989

T-cell phenotype is associated with decreased survival in non-Hodgkin's lymphoma.

This study was undertaken to determine which if any pretreatment factors are statistically significant determinants of the clinical outcome in patients with non-Hodgkin's lymphoma. The pretreatment factors in 20 patients with T-cell lymphoma, including two patients with adult T-cell leukemia/lymphoma (ATLL), and 28 patients with B-cell lymphoma were evaluated. In a stepwise logistic regression analysis, a T-cell phenotype in addition to high grade histology and pleural involvement demonstrated a statistically significant correlation with decreased response rate, when the analysis did not include patients with ATLL. Analysis by means of the Cox proportional hazards model disclosed that the T-cell phenotype retained a statistically significant correlation with survival after adjustments for other prognostic factors, whether the study included the patients with ATLL or not. The decreased response rate and survival of Japanese patients with non-Hodgkin's lymphoma in comparison with those reported in Western countries seem to be due to increased intrusion of T-cell lymphomas. To permit a reliable comparison of reports on new chemotherapeutic regimens from different institutions, the tumor phenotype must be determined in the population studied.

Aged↗
PubMed1989

Multivariate evaluation of determinants affecting regional lymph node metastasis and survival in bladder cancer patients who underwent radical cystectomy.

To elucidate the relative importance of clinicopathologic factors affecting regional lymph node metastasis and survival in bladder cancer patients, multivariate analyses by the logistic regression model and proportional hazards model were performed for 86 patients who underwent radical cystectomy between 1978 and 1988. Clinicopathologic factors included in the analysis were sex, age, prior tumor history, time from onset of symptoms to cystectomy, and tumor characteristics (size, number, growth pattern, grade, stage, infiltration pattern, lymphatic invasion, lymphocytic infiltration around tumors, and lymph node metastasis). Nineteen of eighty-six patients (22%) had regional lymph node metastasis. Univariate analysis showed that lymph node metastasis was related to stage (p = 0.0006), lymphatic invasion (p = 0.006) and infiltration pattern (p = 0.02). Multivariate analysis revealed that stage is the only determinant of statistical significance for lymph node metastasis. High-stage tumors (pT3a-pT4) had 15 times higher risk for lymph node metastasis than low-stage tumors (pTis-pT2). The 5-year survival rates were 25 and 75% for patients with and without lymph node metastasis, respectively. Proportional hazards model revealed that stage is the most significant determinant (p = 0.0001) for survival, followed by lymph node metastasis with borderline significance (0.005 less than p less than 0.1). A two-factor model consisting of stage and lymph node metastasis yielded corrected hazard ratios of 14.7 for stage and 2.3 for lymph node metastasis. The present study quantitatively confirms previous univariate analyses of factors affecting lymph node metastasis and survival in patients undergoing radical cystectomy.

Adult↗
PubMed1989

[Methodological consideration on evaluation of lung cancer screening program: one-step process and two-step process].

A reasonable method to evaluate lung cancer screening program is to measure the reduction in death rate from lung cancer among those randomly allocated to screening program (one-step process). Alternative method is two-step process; step 1 is to measure what proportion of lung cancer patients, can be detected through screening and how early the screening can detected lung cancer patients, and step 2 is to delineate effectiveness of therapy following early detection. Advantages and disadvantages of the two processes were described in view of statistical power and sample size. In addition, a workplace-based screening program using chest X-ray files was mentioned as an example of step 1 of two-step process. The example also included economical consideration of the screening.

Adult↗
PubMed1989

Dealing with the proportional hazards assumption when using the proportional hazards model with a single independent variable.

In order to examine the proportional hazards assumption implicit in the proportional hazards model, three types of simulations were carried out on two groups of hypothetical survival data. Simulation 1 assumed that the hazard rate for one group was higher than that for the other group but that they were not proportional. Simulation 2 was an example of hazard rates crossing each other. Simulation 3 demonstrated the effect of the extent to which the hazard rates crossed. The test statistic, Z:PH, used for testing the proportional hazards assumption was calculated, along with the logarithm of the hazard ratio with its standard error. Although the increase in number of subjects was found to favor detections of violations of the proportional hazards assumption, cases such as those in Simulation 1 were considered acceptable for clinical use. Cases such as those in Simulation 2 were not suitable for the proportional hazards model. Simulation 3 suggested that cases with a substantial degree of unproportionality could be detected to violate the proportional hazards assumption, even when groups of 100 subjects each were involved in the analysis.

Computer Simulation↗
PubMed1988

A notable change in mortality of aplastic anemia observed during the 1970s in Japan.

The age adjusted mortality rate of aplastic anemia in Japan decreased sharply in the mid-1970s; before this time, it had increased only slightly. A report on the survival rate among a substantial number of patients with aplastic anemia showed that patients who sought medical care at the hospital after 1973 had a better survival rate than those who sought care before 1973; the extent of improvement in the survival rate was almost equal to the extent of decrease in the mortality rate. The supply of platelet concentrates was found to increase with the decrease in the age adjusted mortality rate. Although there were several factors that affected the mortality rate from aplastic anemia, the major recognizable factor seemed to be therapeutic improvement, mainly due to the platelet concentrates. Probably neither a decrease in the incidence nor factors related to the data processing of vital statistics played a major role.

Adolescent↗
PubMed1987

Multivariate evaluation of prognostic determinants in bladder cancer patients.

To clarify the relative importance of factors affecting the survival of patients with bladder cancer, a multivariate analysis by Cox's proportional hazards model was performed on 264 patients initially treated from 1973 to 1984 at Nagoya University Hospital. Clinicopathological data included in the analysis were sex, age, symptoms, interval from onset of symptoms to first consultation, smoking history and tumor characteristics (location, size, number, shape, histological grade and stage). The analysis revealed that stage is the most statistically significant determinant for survival, followed by size, irritative symptoms, age and grade in this order. The model composed of the above five determinants yielded hazard ratios of: 4.6 for stage (pT2-pT4 vs. pTa-pT1); 3.1 for size (greater than 3 vs. less than or equal to 3 cm); 2.5 for irritative bladder symptoms (present vs. absent); 2.7 for age (70 years or more vs. younger), and 2.1 for grade (high grade vs. low grade tumors). We conclude that these findings quantitatively confirm previous clinical impressions that accurate staging of the tumors is most important for improving the prognosis of bladder cancer patients, and that each of the above five determinants should be considered when planning an effective initial treatment regimen.

Adenocarcinoma↗
PubMed1987

A workplace-based case-control study of gastric ulcer among male municipal employees in Japan.

In order to detect risk factors of gastric ulcer among male workers in Japan, a workplace-based case-control study was conducted in a municipal government, using cases registered during 1981 to 1983 with individually matched controls. Statistically significant factors in univariate analysis were smoking, time interval from waking up to leaving home for job, meal time for supper, sleeping hours, anxiety, and gloomy feeling. Logistic analysis showed that among the above factors the significant relative risks were 11.9 (95% confidence interval: 1.6-89.4) for 1-9 cigarettes per day, 9.9 (2.6-37.7) for 10 cigarettes or more per day, and 5.3 (1.6-17.5) for gloomy feeling. These findings obtained among the male Japanese workers were almost consistent with those epidemiologic results in other developed countries that smoking and personality traits are major risk factors of gastric ulcer.

Adult↗
PubMed1987

Relationships of age, period, and birth cohort for stomach cancer mortality in Japan.

The mortality data on stomach cancer in Japan during 1955 to 1980 were analyzed by the use of an age-period-cohort model. Although the model could not give a unique solution of age, period, and cohort parameters, several sets of estimates of the parameters clarified particular features of each effect. Within a plausible range, the features were as follows. The period parameter underwent linear change from 1965 to 1980 for males and from 1970 to 1980 for females. The cohort parameters decreased birth cohort by birth cohort, at least among those who were born after 1891. The curve of the age parameter in females showed a shoulder around age 40 and a subsequent upward slope to age 80, while that in males was unimodal. The curve in females was compatible with the idea that there might be two different main entities in stomach cancer. The model also gave estimates of future trends in stomach cancer mortality under the assumption that there would be no additional change in period effect other than that expected from the recent quinquennia. The number of deaths from stomach cancer in males would be rather stable until 2000, and that in females would decline slightly. The age-adjusted and crude mortality rates would continue to decrease at least until 2000.

Adult↗
PubMed1987

Smoking, alcohol drinking and serum carotenoids levels.

Serum carotenoids concentrations in healthy inhabitants, aged 40-79 years, of a community were measured. The results are as follows. 1. The alpha- and beta-carotene and lycopene levels in serum were significantly higher in females than males. The alpha- and beta-carotene concentrations tended to increase with advancing age, this being especially marked for serum beta-carotene levels in males. However, beta-carotene levels were high in females throughout the age range of 50-69 years. There was no significant change in serum level of lycopene with age. 2. There was no significant difference in intake frequency of foods containing large amounts of carotenoids among the groups with or without smoking and drinking, as serum alpha- and beta-carotene levels were closely associated with intake frequency of green-yellow vegetables. 3. Regular alcohol drinkers or current smokers showed lower serum beta-carotene concentrations, and the effect of alcohol drinking on serum carotene level seemed to be larger than that of smoking. A synergistic lowering action of smoking and drinking on serum beta-carotene level was suggested. Among the alcohol drinkers, the more cigarettes consumed per day, the lower the serum beta-carotene level was, but this was not the case among the non-drinkers. Ex-smokers showed intermediate values between current smokers and non-smokers. The results suggest that alcohol drinking and smoking habit might be associated with lower serum beta-carotene level, which in turn may be related to excess incidence of cancer among smokers or drinkers.

Adult↗
PubMed1986

[Dietary habits among smokers].

Differences in dietary habits between smokers and non-smokers were examined, using the data of well-designed case-control study of colon cancer. Smokers took much more coffee, beef and sake than non-smokers, and smokers tended to take meals irregularly. These dietary habits showed dose-response relationship in the amount of smoking. Odds ratio of proportion of smokers with the above four factors to those without any factors was 10.5, and those with two or three factors were 2-6. These results suggest that the interaction of smoking and dietary habits should be analysed in epidemiological study on cancer.

Adult↗
PubMed1985

Leukemia relapse in long-term survivors of acute leukemia.

Between 1964 and 1982, 862 patients with acute leukemia who were collected from medical institutions throughout the country had a survival of 5 years or longer. Their remission has been achieved mainly with a combination therapy of vincristine and prednisone in childhood acute leukemia and daunomycin, cytosine arabinoside, 6-mercaptopurine, prednisone (DCMP) regimen in adult acute leukemia. Among 320 relapsed patients, 88 (38.8%) of 227 children had a primary relapse in the marrow, 85 in the central nervous system (CNS), 37 in the testis/ovary, and 13 in a combined site. The large majority of adult relapsed patients relapsed in the marrow. Ninety-three patients who experienced only one relapse had a much longer prolongation of survival, not yet reaching a median over 14 years after diagnosis, compared to those experiencing two or more relapses. Survival curves in five groups of patients divided by length of maintained remission were investigated by the life table method. In children as well as adults, survival duration in patients on 5 or more years maintained remission was significantly longer than that in the other maintained groups. With respect to relation between frequency of CNS relapse and type of CNS prophylaxis, there was no statistically significant difference between patients who received CNS prophylaxis and patients who did not. However, a better survival was observed in patients who received CNS prophylaxis with cranial radiation plus intrathecal methotrexate. Thus, long-term clinical follow-up might provide important information for the therapeutic strategy against acute leukemia.

Actuarial Analysis↗