Improved human chorionic gonadotropin detection with carboxyl-terminal radioimmunoassay of the beta subunit on concentrated 24-hour urine in patients with testicular cancer

False elevations of human chorionic gonadotropin associated to iatrogenic hypogonadism in gonadal germ cell tumors

Radioimmunoassay (RIA) for fraction beta of the chorionic gonadotropin hormone (HCG-beta subunit) has a clinical value in the management of patients with gonadal germ cell tumors (GCT). Treatment of disease causes temporary or permanent iatrogenic hypogonadism and secondary plasmatic elevations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Small but significant cross-reactions with LH have been observed, resulting in spurious elevations of HCG, as result, also in part, of the lack of specificity of the RIA. Twelve patients with complete response showed high HCG follow-up levels between 1.7 and 7.8 mIU/ml; simultaneous determination of LH and FSH resulted, also, in high levels: 79.9 to 24.9 mIU/ml and 80 to 19.2 mIU/ml, respectively, in females, and 78 to 18 mIU/ml and 65.1 to 5 mIU/ml, respectively, in males. Administration of exogenous hormones resulted in all cases in reduction of LH and FSH values and normalization of HCG. Therefore, relationship between spurious elevations of HCG and the iatrogenic hypogonadism is clarified through this simple technique that is of most importance as regards the adoption of the appropriate therapy.

Human chorionic gonadotropin detected in urinary concentrates from patients with malignant tumors of the testis, prostate, bladder, ureter and kidney

Human chorionic gonadotropin levels in concentrated 24-hour urine and serum were determined by a specific radioimmunoassay of beta-human chorionic gonadotropin in 47 patients with genitourinary carcinoma. Elevated human chorionic gonadotropin levels in urine were observed in 6 of 8 patients with active testicular tumor, 3 of 14 with prostatic cancer, 2 of 10 with bladder cancer, 1 of 2 with ureteral or renal pelvic tumors and 2 of 6 with renal cancer. Of the 14 patients with positive urinary human chorionic gonadotropin 4 had undetectable human chorionic gonadotropin levels in the serum. The tumors of all 8 patients with nontesticular cancer who had increased urinary human chorionic gonadotropin levels were in an advanced clinical stage or of poor histological differentiation. Our results suggest that some nontrophoblastic carcinomas of the genitourinary system are capable of ectopic production of human chorionic gonadotropin, particularly if the malignancy is advanced or poorly differentiated. The radioimmunoassay of beta-human chorionic gonadotropin in concentrated 24-hour urine specimens enhances the sensitivity of detection of ectopic human chorionic gonadotropin production.

The detection and evaluation of human tumor metastases

Many biochemical indices are purported to have clinical utility in the detection and management of neoplasia. Experience gained during the past decade tends to indicate their having a more important role in the detection and monitoring of metastases than of the primary lesion. From this present review of some of the commoner human tumours, it is concluded that such marker substances are important adjuncts in the management of germ cell and certain endocrine and endocrine-related tumours. The carcinoembryonic antigen (CEA) provides a marker for many gastrointestinal cancers, but there are no presently available substances with clinical usefulness for either breast or lung neoplasms. Alternative approaches to the detection of metastases are also presented. The particular use of antibody probes at an immunohistochemical level has been claimed to be able to detect micrometastastic disease in bone marrow or tumour-related monoclonal antibody probes may have application to other cancers in the future.

False-positive and false-negative alpha-feto protein and human chorionic gonadotropin assays in testicular cancer: a double blind study

The rates of false-positive and false-negative serum alpha-feto protein (AFP) and human chorionic gonadotropin (HCG) determinations in 50 patients with testicular cancer utilizing assays from a reference laboratory were studied. Seven (14%) of fifty patients had false-positive and one (2%) of 50 had false-negative serum HCG determinations. Although six (12%) of 50 of serum AFP determinations showed false-positive results; no false-negative rates were encountered for serum AFP. Utilizing simultaneous measurements of serum HCG and luteinizing hormone (LH) measuring urinary HCG by a highly specific carboxyl-terminal assay, one may rule out false-positive occurrences of serum HCG in patients with testicular cancer. This double-blind study also confirmed the need for correlating the clinical status of the patients with elevated serum AFP or HCG in patients with testicular cancer before embarking on any therapy.