泌尿器科領域の悪性腫瘍における癌胎児性抗原(Carcinoembryonic antigen) -第2報-尿路上皮癌患者の血漿CEAおよび尿中CEA様物質について

Abstract

Determinations were made of plasma CEA in 124 bladder cancer and 26 renal pelvic and ureteral cancer patients and also of urinary CEA in 86 bladder cancer patients by radioimmunoassay (zirconylphosphate-gel) with the following results. 1) Plasma CEA levels (mean±SD) thus found were 2.4± 1.6 ng/ml for normal subjects and 3.0±1.9 ng/ml for patients with benign urologic diseases (abbreviated to benign diseases). Patients with localized bladder cancer and those with metastasis gave respective values of 5.7 ±3.9 ng/ml and 10.7±8.lng/ml, which were significantly higher than a corresponding value for those with previous history of bladder cancer of 3.1 ± 1.8 ng/ml (P<0.01). Of patients with renal pelvic and ureteral cancer, those with localized lesion gave a value of 6.0±6.0 ng/ml and those with metastasis showed a value of 13.8±9.9 ng/ml, the latter value being significantly higher than a corresponding value for those with previous history of renal pelvic and ureteral cancer of 3.6±2.4ng/ml (P<0.05). 2) If cases showing plasma CEA levels of 6 ng/ml or above are regarded as CEA-positive, the positivity rates of plasma CEA in bladder cancer patients were 40.8% for the group with localized cancer and 67% for the group with metastasis; both figures were significantly higher than that for the group with previous history of bladder cancer, 7.6% (P<0.01). Among patients with renal pelvic and ureteral cancer, 38.5% of those with localized cancer and 71.4% of those with metastasis were positive for plasma CEA, with the latter figure being found to be significantly higher than a corresponding value for patients with previous history of renal pelvic and ureteral cancer of 16.7% (P<0.05). 3) Fifty-four bladder cancer patients who were followed up for more than 6 months after operation were divided into 2 groups, with and without recurrence, and plasma CEA levels as determined before and I month after operation were compared between the two groups. In the group without recurrence, the plasma CEA values was 6.3±3.2 ng/ml preoperatively and 2.9± 1.6 ng/ml after operation. Of 29 cases in this group, 17 (58.6%) were positive for plasma CEA before operation, while only I (3.4%) was CEA-positive after operation. In the group with recurrence, on the other hand, the pre- and postoperative plasma CEA levels were 7.0±3.9 ng/ml and 7.4±4.4 ng/ml, respectively, and 13 (52%) and 15 (60%), respectively, of 25 cases were found to be CEA-positive pre- and postoperatively. Of 16 cases labeled as positive for plasma CEA at 1 month after operation, 15 (94%) had a recurrence postoperatively, a fact stressing the necessity of making a careful follow-up for possible recurrence of cancer in those cases with the plasma CEA exceeding 6 ng/ml after operation. Of 38 cases categorized as plasma CEA-negative postoperatively, no more than 10 (26%) had a recurrence. 4) Plasma CEA levels were further studied in relation to smoking habit. In 47 patients with benign urologic diseases the mean plasma CEA levels were 3.7±1.3 ng/ml for 17 smokers and 2.6±2.1 ng/ml for 30 non-smokers, with no statistically significant difference between the smokers and non-smokers. Of 47 patients with urothelial cancer, 31 smokers gave a plasma CEA value of 7.7±4.5 ng/ml and the remaining 16 non-smokers had a value of 6.4±3.2 ng/ml; both figures were significantly greater than corresponding values for patients with benign diseases (P<0.01). The positivity rates of plasma CEA were 6% (1/17) for benign disease patients with smoking, 10% (3/30) for those without smoking, 61 % (19/31) for urothelial cancer patients with smoking and 50% (8/16) for those without smoking. Thus, urothelial cancer patients, regardless of whether smokers or non-smokers, showed a significantly higher positivity rate of plasma CEA than benign disease patients (P<0.01). 5) Urinary CEA levels tended to be higher in females than in males. Even benign disease patients exhibited abnormally elevated urinary CEA levels in the presence of urinary tract infection, with a positivity rate in excess of 60%. Of bladder cancer patients without urinary tract infection, males gave a urinary CEA level of 9.4±11.4 ng/ml with a positivity rate of 56%, while females showed respective values of 23.4±36.7 ng/ml and 40%. These values were higher than corresponding values for benign disease patients without urinary tract infection (male: 2.3±2.0 ng/ml, 6%; female: 3.4±3.6 ng/ml, 6%). 6) These results suggest that the plasma CEA as determined by immunoassay provides a useful means of assessing the efficacy of surgical treatment, determining the likelihood of recurrence and the presence or absence of metastasis and evaluating prognosis in patients with urothelial cancer. Further immunochemical studies seem to be indicated for the clarification of what is called urinary CEA-like substance, which is thought to be related to bladder cancer.