Reliability analysis of first and second generation PSA assays.

PURPOSE: To assess the reliability of first and second generation PSA assays. MATERIALS AND METHODS: In the present investigation we sought to compare pretreatment serum PSA levels determined by a first (IMx) and a second (IMMULITE) generation PSA assays to determine whether there were differences. Sera from 545 men were investigated in the range > 0 - 5330 microg/L, and prostatic histology was known, based on either transrectal ultrasound (TRUS), guided systematic needle biopsies, or transurethral resection or prostatectomy. RESULTS: Over the entire range there was an excellent correlation (r > 0.97) between the IMx and the IMMULITE PSA assays. When analyzed according to histology, there was an equivalent slope in the PSA ranges for patients with benign prostatic hyperplasia compared with prostate cancer patients. The area under the ROC curve for the IMx for the total PSA range was 0.7860, and for the IMMULITE assay the area under the ROC curve was 0.7810, a striking resemblance and not different significantly (p=0.87). CONCLUSION: For the majority of men, the first (IMx) and second (IMMULITE) generation PSA assays are equivalent. Small differences between both assays will not be of clinical significance for most men, but should be considered when comparing results of different assays in sequential determinations for a specific man.

Clinical implications of free-to-total immunoreactive prostate-specific antigen ratios.

OBJECTIVE: A study was performed to evaluate the free-to-total prostate-specific antigen (PSA) ratio for discriminating benign prostatic hyperplasia (BPH) or prostate cancer in the intermediate PSA range (2.0-10.0 microg/l) in patients referred for prostate evaluation. In addition, the relationship of free-to-total PSA ratio and tumor grade in prostatic cancer cases, implying a higher concentration of complex PSA in poorly differentiated cancer, was assessed for its predictive value of tumor aggressiveness at the time of diagnosis. PATIENTS AND METHODS: Seven hundred and sixteen patients referred to the out-patient clinics of two urological departments were included in this prospective study. Blood samples were taken for total immunoreactive and free PSA (IMMULITE) determinations prior to any manipulation. The patients were grouped according to their PSA levels: 2.0-4.0 microg/l, 4.0-10.0 microg/l, 10.0-20.0 microg/l and > or = 20.0 microg/l. All patients were categorized, after histological confirmation, as having BPH (n = 423) or prostate cancer (n = 293). In patients with cancer the tumor grade was also assessed. RESULTS: In patients with serum immunoreactive PSA levels in the 2.0-4.0 microg/l range, a free-to-total PSA ratio lower than 22% predicted the presence of prostate cancer with a sensitivity of 67% and a specificity of 63%. The positive- and negative-predictive values were 29% and 90% respectively. Receiver-operating characteristic curve analysis indicated a free-to-total PSA ratio of 22% to be the optimum discriminatory level in this low PSA range. For patients with a serum PSA level between 4.0 and 10.0 microg/l, the threshold ratio of 18% gave a sensitivity of 70%, a specificity of 70%, a positive-predictive value of 46% and a negative-predictive value of 87%. Men with a well differentiated grade of prostate cancer had higher free-to-total PSA ratios than those with less differentiated tumors (p = 0.01). CONCLUSIONS: Our data indicate that the free-to-total PSA ratio, in patients with prostatic disease and with PSA levels in the 2.0-10.0 microg/l range, gives a significant improvement in prediction of cancer over the total immunoreactive PSA value alone. Because of the correlation between a higher tumor grade and a lower free-to-total PSA ratio, this ratio may be helpful in assessing the risk of a poorly differentiated cancer.

Importance of a new tumor marker TRA-1-60 in the follow-up of patients with clinical stage I nonseminomatous testicular germ cell tumors.

BACKGROUND: TRA-1-60 is a new tumor marker for embryonal carcinoma-positive nonseminomatous testicular germ cell tumors (NSTGCT). Upper normal reference value (RV) and serum half-life (t1/2) were determined. The value was determined in the follow-up of 154 patients with stage I NSTGCT. METHODS: TRA-1-60 was measured in normal controls (n = 100) to determine RV and in patients without recurrence for t1/2. In all patients, TRA-1-60 was determined at the time of orchidectomy. In 42 patients with recurrence, values were also evaluated 1 month before and at the time of computed tomography-confirmed recurrence. Predictive values and survival probability were examined and compared with values for alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG). RESULTS: RV was 230 U/ml and t1/2 9.5 days. Elevated TRA-1-60 at the time of orchidectomy was not associated with recurrence. One month before recurrence, 21 of 42 patients had elevated TRA-1-60 levels (50%); 10 were negative for both AFP and hCG. At the time of recurrence, 24 patients had elevated TRA-1-60 levels (57.1%): 9 were negative for AFP/hCG. Patients with TRA-1-60 levels of > 500 U/ml had a poorer recurrence-free survival probability (p = 0.015). CONCLUSIONS: TRA-1-60 is useful in the follow-up of stage 1 NSTGCT. The combination of AFP, hCG, and TRA-1-60 may improve the early detection of recurrence.

Increased urinary levels of Tamm-Horsfall glycoprotein suggest a systemic etiology of interstitial cystitis.

PURPOSE: We investigated the role of Tamm-Horsfall protein in interstitial cystitis. MATERIALS AND METHODS: Urinary Tamm-Horsfall protein excretion was analyzed in interstitial cystitis patients and controls, and bladder biopsy specimens were stained immunohistochemically for Tamm-Horsfall protein. RESULTS: Urinary Tamm-Horsfall protein levels in 28 women with interstitial cystitis were statistically significantly greater than those in 25 female controls. No positive staining for Tamm-Horsfall protein was demonstrated in the bladder tissue from 10 interstitial cystitis cases. CONCLUSIONS: The results support the notion that interstitial cystitis may have a systemic etiology. In addition, this assay might have clinical value in the diagnosis of interstitial cystitis.

Increased urinary IgG/albumin index in normoalbuminuric insulin-dependent diabetic patients: a laboratory artefact.

The previous observation that urinary IgG excretion is increased in normoalbuminuric insulin-dependent (IDDM) patients is unexplained and could possibly be related to a laboratory phenomenon. When untreated urine samples were stored -20 degrees C for 2 to 4 weeks, the IgG/albumin Index (IgG clearance divided by albumin clearance) was higher in normoalbuminuric IDDM patients than in control subjects (0.91 (0.68-1.54), n = 27 vs 0.72 (0.55-0.79), n = 15 (median (interquartile range)), p < 0.05). In normo- and microalbuminuric IDDM patients the IgG/albumin index was higher in urine samples with glucose than without glucose (1.16 (0.93-1.68), n = 11 vs 0.73 (0.50-0.91), n = 16, p < 0.05, and 0.33 (0.23-0.60), n = 17 vs 0.15 (0.10-0.26), n = 14, p < 0.02 for normo- and microalbuminuric patients, respectively). We, therefore, evaluated the preserving effects of glucose and bovine serum albumin (BSA) on urinary IgG after 1 h to 16 weeks of freezing at -20 degrees C in 4 non-diabetic subjects (proteinuria ranging from 0.05 to 8.0 g 24 h-1). Urine samples were either stored without precautions or treated with addition of phosphate buffer, BSA (1%) and glucose 100 and 300 mM). The weekly decline from 1 to 16 weeks of IgG in the urine aliquots diluted 1:1 with buffered glucose 300 mM and glucose 300 mM + BSA 1% was insignificant, whereas urinary IgG declined with all other storage regimes (p < 0.05). These results suggest that glucose in urinary specimens of IDDM patients prevents at least in part the loss of urinary IgG and may thus explain the higher urinary IgG/albumin index when unprocessed urine is stored frozen before assay. Laboratory precautions are necessary when urinary IgG cannot be measured immediately.

Detection of recurrence in patients with clinical stage I nonseminomatous testicular germ cell tumors and consequences for further follow-up: a single-center 10-year experience.

PURPOSE: A wait-and-see policy for patients with stage I nonseminomatous testicular germ cell tumors (NSTGCT) was evaluated in a prospective study. The frequency and time of recurrence, detection of recurrence, and presence of unfavorable prognostic factors were investigated. PATIENTS AND METHODS: During the period 1982 to 1992, 154 patients with stage I NSTGCT (median age, 29 years) underwent orchidectomy and were monitored at follow-up evaluation with physical examinations, alfafetoprotein (AFP) and beta-human choriogonadotropin (hCG) levels, chest x-rays (CXR), and computed tomographic (CT) scans of the abdomen and chest. Multivariate logistic regression analyses were performed to identify prognostic factors. RESULTS: During a median follow-up period of 7 years (range, 2 to 12), recurrence was found in 42 patients (27.3%). All cases of recurrence were detected within 2 years, 90% in the first year after orchidectomy. In 29 patients (69.0%), recurrence was detected in the abdominal lymph nodes. Nine patients (21.4%) had metastases in the retroperitoneum and mediastinum and/or lungs, and four patients (9.6%) had metastases only in the mediastinum or lungs. The majority of recurrences (97.6%) were detected by tumor markers and CT scans. Recurrence was related to the presence of vascular invasion, embryonal carcinoma (E), elevated preoperative hCG level, and absence of mature teratoma (M). Only vascular invasion was an independent risk factor. After polychemotherapy treatment for recurrence, the survival rate for the total group was 98.7%. CONCLUSION: The wait-and-see policy is a reliable method for follow-up monitoring of patients with stage I NSTGCT. Even in patients with unfavorable prognostic factors, it is justified to await the possible appearance of metastases. For the future, it is recommended that CXR be omitted from the schedule, and it might be feasible to discontinue follow-up evaluations after 5 years.

Anti-sulphatide antibodies in peripheral neuropathy.

A study was carried out on 135 patients with chronic idiopathic neuropathy (63), neuropathy associated with monoclonal gammopathy (51, including eight with anti-MAG antibody activity) and the Guillain-Barré syndrome (GBS) (21). Serum IgM, IgG and IgA anti-sulphatide antibody titres were compared with titres in 304 patients with other neurological or immunological diseases and in 50 normal subjects. Titres were presented a) as the highest serum dilution at which reactivity could be detected, and b) in the linear region of the optical density curve. A substantial number of patients with neurological or immunological diseases had higher titres than normal subjects. Compared with normal and disease controls, five patients with neuropathy associated with IgMk monoclonal gammopathy had raised titres of IgM anti-sulphatide antibodies and one patient with GBS had raised IgM, IgG and IgA anti-sulphatide antibodies in the acute phase of the disease. Two patients had a predominantly axonal sensory neuropathy with presenting symptoms of painful paresthesiae and minimal neurological deficit. Three patients had a predominantly demyelinating sensorimotor neuropathy associated with anti-MAG antibody activity. The patient with GBS had extensive sensory loss and antibody titres returned to normal within three weeks. Raised titres of anti-sulphatide antibodies occurred in several types of neuropathy, but all had some degree of sensory impairment and associated immunological abnormality.

Cancer-associated antigen CA 195 in patients with mucinous ovarian tumours: a comparative analysis with CEA, TATI and CA 125 in serum specimens and cyst fluids.

The CA 195 levels in ovarian cyst fluids from malignant mucinous tumours (median 2,300,000 U/ml) were significantly higher than the levels in benign mucinous tumours and malignant non-mucinous tumours (medians of 26,800 and 1,700 U/ml, respectively, p = 0.039 and 0.011). Also, the carcinoembryonic antigen (CEA) and tumour-associated trypsin inhibitor (TATI) levels in cyst fluid from mucinous tumours were much higher than those in non-mucinous tumours. Pretreatment serum CA 195 levels were found to be elevated (> 10.5 U/ml) in 72% of the patients with malignant mucinous tumours (n = 25), compared with 35% in malignant non-mucinous tumours and 28% in benign mucinous tumours. The positivity rate shown for serum CA 195 in malignant mucinous tumours was higher than that measured for serum TATI, CA 125 or CEA (60, 53 and 42%, respectively). Measurement of serum CA 195 can be valuable in the clinical management of patients with mucinous ovarian cancer.

Tissue polypeptide-specific antigen: a discriminative parameter between prostate cancer and benign prostatic hypertrophy.

The serum concentration of the cell proliferation marker TPS (tissue polypeptide-specific antigen) was compared with the tumour marker PSA (prostate specific antigen). PSA was found elevated in 50% of the benign prostatic hypertrophy (BPH) patients, in 88% of the patients with active prostate cancer and in 40% of the patients who were in an inactive phase. For TPS these values were 6, 34 and 0%, respectively. The metastatic progression was biochemically mirrored by pronounced elevations of PSA and TPS. These data suggest that TPS might be a valuable adjunct in the diagnosis and follow-up of patients with prostate cancer, especially in differentiating benign from malignant deterioration of the disease.

Serum lactate dehydrogenase isoenzyme 1 activity in patients with testicular germ cell tumors correlates with the total number of copies of the short arm of chromosome 12 in the tumor.

The aim of our study was to assess the relationship between the serum lactate dehydrogenase isoenzyme 1 (S-LDH-1) activity in patients with testicular germ cell tumors and the number of copies of the short arm of chromosome 12 (12p) present in tumor. Twenty-seven adult patients with measurable tumor lesions were studied. Twenty-five had three or more copies of chromosome 12 per cell in the tumors. Nineteen had one or more copies of a specific chromosomal abnormality, an isochromosome of the short arm of chromosome 12, i(12p). Fourteen had increased S-LDH-1 levels. S-LDH-1 activity correlated significantly with the product of total tumor volume and the total number of copies of the short arm of chromosome 12 present per cell (total tumor 12p). We conclude that the total number of copies of the short arm of chromosome 12 in the tumors is most probably a factor contributing to the LDH-1 activity released from the tumors.

Maternal serum alpha-fetoprotein levels and fetal outcome in early second-trimester oligohydramnios.

Early second-trimester oligohydramnios was associated with normal maternal serum alpha-fetoprotein (MSAFP) levels in nine out of 26 cases (35 per cent). Congenital malformations of the fetal urinary tract resulting in fetal anuria were present in nine cases; in seven of them, normal MSAFP levels were measured. In contrast, normal MSAFP levels were established in only 2 out of the 17 cases without fetal malformations. These data suggest that fetal urine is the major source of elevated AFP in the maternal compartment in early second-trimester oligohydramnios. This is further supported by the lack of any relationship between concentrations of MSAFP non-reactive with Concanavalin A, originating mainly from the yolk sac-derived amniotic fluid AFP pool, and the presence of fetal diuresis. Three out of 26 women had experienced early second-trimester oligohydramnios in a previous pregnancy, suggesting the existence of a recurrence risk for this condition.

Anti-GM1 antibodies in patients with Guillain-Barré syndrome.

Anti-GM1 antibodies were measured in 22 patients with the Guillain-Barré syndrome (GBS) and compared with anti-GM1 antibody activity in patients with other neurological or immunological diseases and in normal subjects. Four out of 22 patients with GBS had raised IgM, IgG, or IgA anti-GM1 antibody activities. All four patients were tetraparetic with only minimal or no sensory deficit. Three of the patients had highly raised antibody activity and showed severe residual deficits, while of the remaining patients with GBS, only one remained severely affected. One patient had anti-GM1 antibodies specific for GM1, whereas the other three patients showed antibody activity with asialo-GM1 or GD1b. The presence of anti-GM1 antibodies may define a subgroup of patients with GBS who have a poor prognosis.

Origin of raised maternal serum alpha-fetoprotein levels in second-trimester oligohydramnios.

Concanavalin A (Con A) subtyping of alpha-fetoprotein (AFP) revealed higher concentrations of AFP non-reactive with Con A in sera of 12 pregnant women with second-trimester oligohydramnios and raised total serum AFP levels than in sera of 42 pregnant women with raised total serum AFP levels and a normal amniotic fluid volume. This suggests that in oligohydramnios the origin of excess AFP in the maternal compartment is amniotic fluid. It is proposed that oligohydramnios and the associated raised maternal serum AFP levels are caused by damage of the fetal membranes prior to 16 weeks of gestation resulting in leakage of amniotic fluid to the decidual tissue and resorption in the maternal circulation.

Complement activation and the production of inflammatory mediators during the treatment of severe sepsis in humans.

Sepsis or septic shock is frequently associated with activation of the complement system, coagulation and fibrinolytic changes and the release of several cytokines. In this study we analyzed the relation of complement activation to the inflammatory mediators, hemodynamic and biochemical parameters and severity of illness and outcome in 20 consecutive patients with clinically defined sepsis. Levels of C3a and C3d were elevated in 90% of the patients (median levels 0.19 mg/l and 8.6 mg/l respectively) in comparison to 14% and 42%, respectively of 7 patients with non-septic shock. Levels of C4 were decreased in only 1 of the 20 septic patients. Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, Levels of TNF and IL-6 were elevated in 94% and 100% of the patients, respectively (median levels 122 ng/l and 1300 U/ml) and were clearly interrelated (r = 0.67, p less than 0.01). C3a levels correlated with the APACHE II score (r = 0.57, p less than 0.05) and high C3a levels were associated with fatal outcome (p less than 0.05). C3a was also correlated inversely with mean arterial pressure (r = 0.50, p less than 0.01). Levels of complement C3a and C3d significantly correlated with levels of plasminogen activator inhibitor-1 (PAI) and correlated inversely with AT-III levels. We found no correlation between these complement products and leukocyte counts or lactate levels, nor was there a correlation between C3a or C3d and the cytokines TNF and IL-6. Levels of C3a and C3d did not decrease significantly during the first 24 h of treatment, in contrast to a clear decrease in IL-6 levels in all patients and a decrease in TNF in the surviving patients. TNF levels remained stable or increased in the non-survivors. We conclude that both the complement system and the cytokine system are involved in the pathogenesis of septic shock and may be involved in the development of some of the fatal complications like hypotension and disseminated intravascular coagulation.

TRA-1-60: a new serum marker in patients with germ-cell tumors.

TRA-1-60 is a monoclonal antibody (MAb) that recognizes a mucin-like antigenic determinant expressed on the surface of embryonal carcinoma (EC) progenitor cells. In order to determine whether this antigen is released into the serum of patients with a non-seminomatous germ-cell tumor (NSGCT), we developed a sensitive 2-step immunoenzymometric assay. Of 42 EC-positive NSGCT patients tested, 32 (76%) were found to release TRA-1-60-reactive antigen into their serum, in contrast to 1 positive finding in 10 EC-negative NSGCT patients. The marker was found in 67% (10/15) of the EC-positive patients who were negative for both AFP and HCG. Sera from seminoma patients did not contain elevated levels of the TRA-1-60 antigen. Therefore, we propose that the TRA-1-60 antigen is a useful additional serum marker for following the progress of NSGCT(EC+) patients.

Aggressive chemotherapy for acute leukaemia frequently causes intestinal protein leakage.

Cytostatic drugs are known to produce disturbances in intestinal absorption of carbohydrates. To further explore the gastrointestinal (GI) toxicity of cytostatic therapy, 37 patients with acute leukemia were investigated during and/or after remission induction courses by the use of the differential sugar absorption test (DSAT) and the intestinal clearance of alpha-1-antitrypsin (ClAAT). The ratio of the lactulose to the mannitol excretion in the urine was found abnormal in 44% of the tests. The ClAAT was increased in 74% of tests. The tests results differed considerably from patient to patient and depended on the chemotherapy course; correlation between the tests was low, probably indicating the unrelated pathophysiological processes were measured. After haematological regeneration, abnormal test results normalised. It is concluded that aggressive chemotherapy not only causes a reduction in the absorption of sugars, but commonly also protein leakage. These GI side-effects are reversible, and the application of both tests in combination provides a practical and reproducible method for investigation of GI toxicity in patients treated with cytostatic drugs.

Alpha-fetoprotein-lectin binding as a marker of tumour activity or liver damage.

To establish whether alpha-fetoprotein (AFP) produced in the early post-treatment phase of a patient with a germ cell tumour of the testis or the ovary originates from the tumour or is due to an underlying disturbance in liver function, the binding of AFP to concanavalin A (Con A) was investigated as a discriminative variable. A two-step assay is described that can distinguish the type of AFP produced at levels as low as 10 ng/ml. A Con A-binding ratio of 12-43% was found in the patients with disseminated germ cell tumours and in patients with AFP-positive gastrointestinal carcinomas. AFP from the liver gives ratios below 10%.