膀胱癌における酵素学的研究 第1編: 膀胱癌患者の糖負荷による血清lactic dehydrogenaseおよびそのisoenzymeの変動について

Abstract

There have been many papers regarding the changes of various enzyme levels in malignant diseases since Gutman's work in 1933 on acid phosphatase in carcinoma of the prostate. No enzymological diagnostic method specific for malignant diseases is, however, established yet. Since the first report of Hill and Levi on high serum lactic dehydrogenase of the cancer-bearing individuals, this enzyme has been studied by many researchers. As to urogenital malignancies, enzymological studies were mainly focused on acid phosphatase and lactic dehydrogenase in carcinoma of the prostate, and few studies have been made on tumor of the bladder. Moreover, previous studies were not dynamic and did not follow the changes with course of time. Here the author tried a dynamic study on LDH and LDH isoenzymes as well as cholinesterase and transaminase by means of observation of changes after loading sugar. In this part, a report was made on serum lactic dehydrogenase (SLDH) and its isoenzymes. Thirty-eight patients with bladder tumor, either pre-treatment or post-treatment state and 13 controls were chosen for this study. Individuals showing fasting blood sugar higher than 120 mg/dl were excluded. The subjects were placed on the diet of 2, 400 calories per day. Sugar loading was given by drip infusion of 500 ml of 10% glucose in D/W for two hours, from 7.00 p. m. to 9.00 p. m. of each of two successive experimental days. Blood sample was obtained and submitted for measurement of SLDH and its V-fraction in the morning of each experimental day and the third day. Measurement of SLDH was carried out by using Iatron's kit on Caubard's method and that of V-fraction by thin layer gel electrophoresis on Wieme's method. The results were as follows. 1) Only few cases showed glucosuria after infusion of the sugar fluid. No glucosuria was noted one hour after completion of infusion when blood sugar was that of pre-infusion level. 2) Patients with bladder tumor in pre-treatment state showed SLDH and SLDH-V fraction significantly higher than the controls in average (p<0.05). Percentage of cases showing abnormally high value did not exceed 23.7% for SLDH and 37% for SLDH-V fraction. Cases of high stage or high malignancy showed higher SLDH and SLDH-V fraction level than those of low stage or low malignancy. 3) Sugar loading produced significant drop of SLDH and SLDH-V fraction level in the pretreatment patients group (SLDH; P0~48<0.01, SLDH-V: P0~48<0.02), whereas no obvious change was observed in the controls. Percentage of the patients who showed drop of the enzyme level greater than 20% remained 34.2% for SLDH and 40.7% for SLDH-V. The depression of the enzymes was significantly great in high satge or high malignancy group but not significantly great in the low stage or low malignancy group. 4) The patients of the post-treatment group did not show the changes of SLDH and SLDHV after sugar loading as observed in the pre-treatment group. As conclusion, the patiens with pre-treatment bladder tumor showed SLDH and SLDH-V fraction higher than the controls. In some of them, SLDH and SLDH-V fraction were significantly lowered by sugar loading. Post-treatment group free of tumor recurrence showed the same pattern of the enzymes with the controls even after the sugar loading test. Therefore, this kind of study would be of help for clinical follow-up after treatment of bladder tumor.