The role of serum prostatic acid phosphatase as a tumor marker in men with advanced adenocarcinoma of the prostate

Serial serum prostatic acid phosphatase levels were obtained every 4 hours during a 48-hour interval from 10 men with stage D adenocarcinoma of the prostate. No therapeutic or diagnostic manipulations occurred during sample procurement, so that the amount of fluctuation of serum prostatic acid phosphatase levels that can be expected in these patients could be determined. The coefficient of variation for each man ranged from 16.67 to 43.68 per cent, which was significantly higher than the expected 8 per cent coefficient of variation determined with a control sample. The maximum percentage variations above and below the mean were 79 and 50 per cent, respectively. The average percentage variation in all patients was within 50 per cent greater than and 50 per cent less than the mean value of prostatic acid phosphatase. Thus, the usefulness of serum acid phosphatase by radioimmunoassay as a clinical tumor marker is limited by the number of serial assays needed to establish a mean. Based on these findings, certain guidelines are suggested.

A simple semiquantitative radiometric measurement of antithyroglobulin antibodies in human serum. Comparison with hemagglutination method

A simple solid-phase radiometric assay for the measurement of thyroglobulin autoantibodies (TgRA) was developed and evaluated. The assay is semiquantitative, and the results were expressed as a ratio between sample versus negative control (normal human serum). In 59 normal subjects, the mean ratio was 0.93 +/- (SD) 0.34. Thyroglobulin antibodies by radiometric assay, by hemagglutination (TgHA), as well as microsomal antibodies by hemagglutination (MCHA) were measured in 41 patients with a histopathologic diagnosis of Hashimoto's thyroiditis (n = 22), adenomatous goiter (n = 10), carcinoma (n = 5), adenoma (n = 4), and in 59 patients without histopathologic diagnosis of thyroid disease. In patients with Hashimoto's thyroiditis, TgRA, TgHA, and MCHA were positive in 54, 31, and 81% of patients, respectively. 1 patient had positive TgRA with negative MCHA levels, and 2 had negative antibody titers by all methods. Thyrotropin-stimulating hormone levels were elevated (greater than 10 microU/ml) in 17 of these patients. Our results suggest that although the TgRA method is more sensitive than TgHA for detecting thyroglobulin antibodies, its diagnostic sensitivity is not equal to that of MCHA.

Effect of thyroxine on immune response in C57Bl/6J mice

The effect of T4 treatment (40 micrograms, 5 times/week) on immune function in C57Bl/6J mice was studied. The primary antibody synthesis as measured by the plaque-forming cell (PFC) assay demonstrated significant suppression in mice treated with T4 for 30 days. Mitogen assays using PHA and Con A demonstrated significant suppression of cellular immune responses as measured by [3H]thymidine incorporation. The effect was reversed when the treatment was discontinued and a normal response reappeared after 14 days. Allogeneic skin grafts (donor A/J mice) showed prolonged survival (median survival time, 13.5 days) in T4-treated mice as compared to control untreated mice (median survival time, 11 days). Further experiments using Chromium 51 assay for delayed type hypersensitivity also showed suppressed response. These results suggest that treatment with T4, in the above doses and duration, cause immunosuppression in C57Bl/6J mice.

Serum beta 2-microglobulin and interferon in homosexual males: relationship to clinical findings and serologic status to the human T lymphotropic virus (HTLV-III)

The identification of the human T cell lymphotropic virus (HTLV-III) as the presumed etiologic agent for AIDS has stimulated a re-examination and allowed better understanding of many of the immunologic abnormalities described in high risk individuals with and without clinical disease. Currently needed are useful predictors of clinical progression which will allow better counselling, earlier diagnosis and effective treatment of high risk individuals. We have examined the principles of test selection including sensitivity, specificity, predictive value and overall test efficiency for serum beta 2 microglobulin (beta 2M), serum interferon (IFN) and antibody to HTLV-III (HTLV-III Ab) in a group of 113 homosexual men and 62 controls. The presence of HTLV-III Ab and elevated serum beta 2M appear to be the most sensitive markers of immune dysregulation in the study group but also proved to be the least specific. Rising levels of serum beta 2M correlated with clinical severity where HTLV-III Ab positivity did not. The detection of elevated levels of acid labile serum IFN alpha was most specific for full-blown AIDS and was overall the most efficient test when compared with HTLV-III Ab, serum beta 2M and lymphocyte subpopulations. We believe that further examinations of the principles of test selection for immunologic abnormalities in AIDS may lead to potential applications for these tests in patient management.

Dependence of tolerance dose on irradiated volume in radiotherapy, and determination of volume corrected time, dose and fractionation factors

Clinical observations demonstrate that the tolerance dose depends on the volume of normal tissues irradiated. It has been found to decrease if volume size irradiated increases. A relationship between tolerance dose and volume irradiated has been derived. The time, dose and fractionation (TDF) factors given by Orton and Ellis (1973) do not include the effect of volume size of irradiation. That relationship has been used to derive equations of partial tolerance (PT) and TDF factor incorporating the treatment volume size. The incorporation of this factor becomes more important when treating deep-seated tumours and when large volumes of normal tissue are involved. The value of the TDF factor changes by 30% when volume irradiated increases from 500 to 1400 cc for 200 cGy per fraction in three fractions per week schedule.

Immunochemical measurement of serum prostatic acid phosphatase (PAP). Clinical evaluation of radioimmunoassay and counter immunoelectrophoresis

Two radioimmunoassay procedures (RIA-1 and RIA-2) were evaluated for the quantitation of prostatic acid phosphatase in serum and compared with the enzymatic method and counter immunoelectrophoresis method for their specificity and sensitivity. Sera from 168 patients were analyzed and these included: normals, 27; untreated prostatic cancer patients Stage A, 2; Stage C, 3; Stage D, 17; cancer of prostate treated with different modalities, 42; sarcoma of prostate, 1; prostatitis, 3; nonprostatic carcinoma, 17; and benign prostatic hyperplasia (BPH), 56. RIA-1 procedure appeared more sensitive (82% sensitivity) and specific (94.5% specificity) than the RIA-2 procedure (68% sensitivity and 91.8% specificity), but the differences were not statistically significant. The enzymatic method was found to be least sensitive (63.6% sensitivity) but also the most specific (100% specificity). Only 69 of the specimens were analyzed by counter immunoelectrophoresis, which showed sensitivity of 87% and specificity of 51.4%. False positives were observed more often in patients with nonprostatic cancer and BPH. The variations in diagnostic specificity of immunologic assays suggest the need of characterization of each antibody specificity.