Pre-operative serum level of tumour-associated trypsin inhibitor and residual tumour size as prognostic indicators in Stage III epithelial ovarian cancer

OBJECTIVE

To evaluate the use of the pre-operative tumour-associated trypsin inhibitor (TATI) level and residual tumour size at primary surgery as a prognostic indicators for patients with Stage III epithelial ovarian cancer.

DESIGN

Retrospective cohort study.

SETTING

Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.

PARTICIPANTS

Ninety-eight women with Stage III ovarian cancer.

METHODS

TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 microg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.

MAIN OUTCOME MEASURES

Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.

RESULTS

Surgery was optimal (residual tumour size < or = 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level < or = 22 microg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 microg/L. Patients with optimal surgery and a pre-operative TATI > 22 microg/L had a twofold relative risk of death compared with those with a pre-operative TATI < or = 22 microg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 microg/L.

CONCLUSIONS

Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials.

Advances in the laboratory diagnostics of acute pancreatitis

Acute pancreatitis is a rather common abdominal disorder. In most patients the disease is mild, but about 20% of cases develop a severe necrotizing form of the disease with complications. In an emergency setting, the diagnosis of acute pancreatitis remains problematic and several patients with severe disease are diagnosed only at autopsy. Measurements of amylase or lipase are the principal laboratory methods for diagnosing acute pancreatitis. However, their sensitivity and specificity are generally considered unsatisfactory. Recent advances in the knowledge of the pathogenesis of acute pancreatitis and advances in laboratory technology have revealed new diagnostic possibilities. Especially assays based on trypsin pathophysiology have brought new alternatives for diagnostics and severity grading of the disease. Additionally, development of phospholipase A2 determinations and discovery of a new pancreatic protein, pancreatitis-associated protein, are very interesting. This article summarizes the value of new methods in the laboratory diagnostics of acute pancreatitis.

Identification of choriocarcinoma by the hCG beta-to-hCG proportion in patients with delayed diagnosis caused by contraceptive use

The use of contraceptives, especially subdermal implants and levonorgestrel-containing intrauterine device (IUD), often cause irregular bleeding. Thus, they may mask unsuspected choriocarcinoma, which also often presents with abnormal bleeding. Choriocarcinoma is mostly curable with combination chemotherapy, but delayed diagnosis can lead to treatment failure. Two cases of choriocarcinoma with considerable delay in diagnosis, due partly to contraceptive use, are reported. The proportion of human chorionic gonadotropin-beta (hCG beta) and total hCG immunoreactivity showed that the proportion of hCG beta was elevated at presentation in both cases.

Increased serum trypsinogen 2 and trypsin 2-alpha 1 antitrypsin complex values identify endoscopic retrograde cholangiopancreatography induced pancreatitis with high accuracy

AIMS

To evaluate the clinical utility of two new tests for serum trypsinogen 2 and trypsin 2-alpha 1 antitrypsin complex (trypsin 2-AAT) in diagnosing and assessing the severity of acute pancreatitis (AP) induced by endoscopic retrograde cholangiopancreatography (ERCP).

PATIENTS

Three hundred and eight consecutive patients undergoing ERCP at Helsinki University Central Hospital in 1994 and 1995.

METHODS

Patients were followed prospectively for pancreatitis and clinical outcome. They were tested for serum trypsinogen 2, trypsin 2-AAT, and amylase in samples obtained before and one, six, and 24 hours after ERCP.

RESULTS

Pancreatitis developed in 31 patients (10%). Their median serum trypsinogen 2 increased 26-fold to 1401 micrograms/l at six hours after the procedure and trypsin 2-AAT showed an 11-fold increase to 88 micrograms/l at 24 hours. The increase in both markers was stronger in severe than in mild pancreatitis, and in patients without pancreatitis there was no significant increase. Baseline trypsinogen 2 and trypsin 2-AAT concentrations were elevated in 29% and 32% of patients, respectively. The diagnostic accuracy of a threefold elevation over the baseline value was therefore analysed. The sensitivity and specificity of these parameters in the diagnosis of post-ERCP pancreatitis was 93% and 91%, respectively, for serum trypsinogen 2 at six hours after the examination, and 93% and 90%, for trypsin 2-AAT at 24 hours.

CONCLUSIONS

Serum trypsinogen 2 and trypsin 2-AAT reflect pancreatic injury after ERCP. High concentrations are associated with severe pancreatic damage. The delayed increase in trypsin 2-AAT compared with trypsinogen 2 appears to reflect the pathophysiology of AP. A greater than threefold increase in trypsinogen 2 six hours after ERCP is an accurate indicator of pancreatitis.

Disappearance of human chorionic gonadotropin and its alpha- and beta-subunits after term pregnancy

We have used high-specificity and precision immunofluorometric assays to measure the elimination half-times of human chorionic gonadotropin (hCG), hCG alpha, and hCG beta in serum over 21 days after delivery in six women with term pregnancies. Baseline concentrations and half-times were calculated with the use of a curve-fitting algorithm for multiexponential decay. In contrast to the two-component model, a three-component exponential function with baseline provided a fit for which predicted values could not be distinguished from the observed values by analysis of variance. Median half-times were 3.6, 18.0, and 53.0 h for hCG; 1.0, 23.4, and 194 h for hCG beta; and 0.6, 6.2, and 21.9 h for hCG alpha. The mean ratio of hCG alpha to hCG decreased rapidly from 36.9% to 3.3% on day 3; thereafter it increased to 64.3% 21 days after delivery because of a higher baseline concentration of hCG alpha. hCG beta had the slowest total elimination rate, and the ratio of hCB beta to hCG in serum increased from 0.8% before delivery to 26.7% after 21 days. If the metabolism of hCG and hCG beta is similar in patients with trophoblastic disease, the ratio of hCG beta to hCG must be evaluated with caution in samples taken several days after initiating therapy. We conclude that the disappearance of hCG beta from plasma is slower than previously recognized and that the ratios of hCG beta or hCG alpha to intact hCG vary as a function of postpartum time. Such information may be important in clinical studies of pregnancy disorders.

Maternal serum screening for Down's syndrome on population basis

BACKGROUND

The favorable attitude among the public towards prenatal diagnostics in Finland allowed us to start a trial on population basis when screening for Down's syndrome by maternal serum markers and age was introduced.

METHODS

Screening by maternal serum markers for Down's syndrome was offered to all 17,200 pregnant women in the Helsinki area during the study period of 2.5 years. Screening due to advanced maternal age, 37 years or more, was continued as previously, and 1133 pregnant mothers used this option. Alpha-fetoprotein, human chorionic gonadotrophin, and during the first year also unconjugated estriol were used as markers.

RESULTS

The uptake of serum screening was 84%. The proportion of false positive results i.e. risk for Down's syndrome, 1:350 or more at term, was initially 5.7%. After ultrasound scan 4.1% of the mothers remained 'screen positive'. The amniocentesis or chorionic villus sampling uptake was 98.4%. Ten out of eighteen cases of Down's syndrome were detected by maternal serum screening, sensitivity 56%, 95% CI 31-79%. Other chromosomal abnormalities were found in three cases, and there were four cases of mosaicisms confined to the placenta. These were trisomies 16, 7 and 2, and tetraploidy. Elevated serum alpha-fetoprotein was found initially in 0.7% of the cases. One case of congenital nephrosis of the Finnish type and ten other, mainly structural, abnormalities were detected by high AFP.

CONCLUSIONS

The screening was well received by the mothers. The detection rate of 56% is in the same range as in previous studies. Ultrasound scan before the test would effectively lower the false positive rate caused by incorrect timing.

Prostate-specific antigen forms a complex with and cleaves alpha 1-protease inhibitor in vitro

BACKGROUND

Complexes between prostate-specific antigen (PSA) and alpha 1-protease inhibitor (API) occur in serum and they are of potential interest in the diagnosis of prostate cancer. Pure PSA-API complexes are needed for development of specific assays, but complex formation has not earlier been achieved in vitro.

METHODS

PSA was incubated with an excess of API at 37 degrees C. Complexes formed were quantitated by an immunofluorometric assay using antibodies to PSA and API. The products were further characterized by SDS-PAGE, immunoblotting and amino-acid sequencing. PSA-API was purified by gel filtration and immunoaffinity chromatography.

RESULTS

PSA formed an SDS-stable 80-kDa one-to-one complex with API. The rate of formation of PSA-API was slow compared to that of PSA-alpha 2-macroglobulin (A2M) or PSA-alpha 1-antichymotrypsin (ACT), and only about 15% of PSA complexed with a 5-fold molar excess of API at 37 degrees C in 7 days. A major part of API was cleaved between 358-Met and 359-Ser, causing loss of inhibitory activity. PSA-API formed in vitro was purified by gel filtration and immunoaffinity chromatography with anti-PSA antibody. After incubation for 7 days at 37 degrees C, 30-40% of the complex had dissociated causing release of active PSA and proteolytically cleaved inactive API. The dissociation was accelerated in the presence of serum, and released PSA complexed with A2M and ACT.

CONCLUSIONS

PSA forms a complex with API in vitro, but the reaction is slow and part of the API is cleaved. Complex formation is reversible and released PSA is enzymatically active, whereas API is inactivated. Purified PSA-API will facilitate development of quantitative immunoassays for this complex.

Activation of type IV procollagenases by human tumor-associated trypsin-2

Increased production of proteinases, such as matrix metalloproteinases (MMPs), is a characteristic feature of malignant tumors. Some human cancers and cell lines derived from them also express trypsinogen, but the function of the extrapancreatic trypsin has remained unclear. In this study we cloned and sequenced trypsinogen-2 cDNA from human COLO 205 colon carcinoma cells and characterized the ability of the enzyme to activate latent human type IV procollagenases (proMMP-2 and proMMP-9). As shown by cloning and N-terminal amino acid sequencing, the amino acid sequence of tumor-associated trypsin-2 is identical to that of pancreatic trypsin-2. We found that both pancreatic trypsin-2 and tumor cell-derived trypsin-2 are efficient activators of proMMP-9 and are capable of activating proMMP-9 at a molar ratio of 1:1000, the lowest reported so far. Human trypsin-2 was a more efficient activator than widely used bovine trypsin and converted the 92-kDa proMMP-9 to a single 77-kDa product that was not fragmented further. The single peptide bond cleaved by trypsin-2 in proMMP-9 was Arg87-Phe88. The generation of the 77-kDa species coincided with the increase in specific activity of MMP-9. In contrast, trypsin-2 only partially activated proMMP-2. Trypsin-2 cleaved the Arg99-Lys100 peptide bond of proMMP-2 generating 62-65-kDa MMP-2 species. Trypsin-2-induced proMMP-2 and -9 conversions were inhibited by tumor-associated trypsin inhibitor added either prior to or during activation indicating that proMMPs were not activated autocatalytically. Trypsin-2 also activated proMMPs associated with tissue inhibitor of matrix metalloproteinases, the complexes of which are thought to be the major MMP forms in vivo. The ability of human tumor cell-derived trypsin-2 to activate latent MMPs suggests a role for trypsin-2 in initiating the proteinase cascade that mediates tumor invasion and metastasis formation.

Determination of urinary free cortisol by HPLC

We here report a reversed-phase HPLC method for the determination of free cortisol in human urine, using methylprednisolone as the internal standard. Before chromatography, samples were extracted with a C18 solid-phase extraction column and the steroids were separated on a LiChrospher 100 C18 column with a mobile phase of methanol/acetonitrile/water (43/3/54 by vol). Linearity, precision, and accuracy of the method were established. The detection limit was 10 pmol of cortisol, and total CVs were < 8%. With various solid-phase extraction columns the recovery of cortisol was 36-97%; recovery of the internal standard was 43-85%. Study of interference by 6 other steroids and metabolites and 24 drugs showed that carbamazepine and digoxin partly overlapped with cortisol, but this interference could be reduced by modification of the mobile phase. The HPLC method was compared with an RIA and an automated immunoassay method. The results obtained by HPLC averaged 40% of the RIA values.

Immunoprocedures for detecting human chorionic gonadotropin: clinical aspects and doping control

The pregnancy hormone human chorionic gonadotropin (hCG) is also present at low concentrations in plasma and urine of men and nonpregnant women. hCG immunoreactivity occurs in various molecular forms: Besides the intact hCG heterodimer, considerable amounts of proteolytically cleaved forms, free subunits, and fragments are found in plasma and urine. Especially in urine, proteolytic fragments constitute a major part of the hCG immunoreactivity. The different forms of hCG cross-react to various degrees in immunoassays and constitute a problem for standardization of specific hCG determinations. After injection of hCG (10,000 IU of Pregnyl; Organon), above-normal concentrations of hCG can be detected in serum and urine for 7-11 days. Most immunoassays for hCG also measure hCG beta. Quantitative hCG determinations are mainly performed on serum samples, and very few commercial hCG determinations have been validated for determination of urine samples. Considerable care must therefore be exercised when utilizing such assays to analyze urines for doping control.

Rapid measurement of urinary trypsinogen-2 as a screening test for acute pancreatitis

BACKGROUND

Acute pancreatitis can be difficult to diagnose. We developed a rapid dipstick screening test for pancreatitis, based on the immunochromatographic measurement of urinary trypsinogen-2.

METHODS

We prospectively compared the urinary trypsinogen-2 dipstick test with a quantitative urinary trypsinogen-2 assay, a urinary dipstick test for amylase, and serum and urinary amylase assays in 500 consecutive patients with acute abdominal pain at two emergency departments. Acute pancreatitis was diagnosed according to standardized criteria.

RESULTS

The urinary trypsinogen-2 dipstick test was positive in 50 of the 53 patients with acute pancreatitis (sensitivity, 94 percent), including all 7 with severe pancreatitis. Two patients with urinary trypsinogen-2 concentrations below the sensitivity threshold of the test (50 ng per milliliter) and one with a very high concentration had false negative results. The test was also positive in 21 of the 447 patients without pancreatitis (specificity, 95 percent), including 7 with abdominal cancers, 3 with cholangitis, and 2 with chronic pancreatitis. The sensitivity and specificity of the dipstick test were similar to those of the quantitative urinary trypsinogen-2 assay and higher than those of the urinary amylase dipstick test. The serum amylase assay had a sensitivity of 85 percent (with a cutoff value of 300 U per liter for the upper reference limit) and a specificity of 91 percent. The sensitivity and specificity of the urinary amylase assay (cutoff value, 2000 U per liter) were 83 and 88 percent, respectively.

CONCLUSIONS

In patients with acute abdominal pain seen in the emergency department, a negative dipstick test for urinary trypsinogen-2 rules out acute pancreatitis with a high degree of probability. A positive test usually identifies patients in need of further evaluation.

Urinary trypsinogen-2 test strip in detecting ERCP-induced pancreatitis

BACKGROUND AND STUDY AIMS

We have evaluated a new urinary trypsinogen-2 test strip, based on the principle of immunochromatography, in the diagnosis of acute pancreatitis induced by endoscopic retrograde cholangiopancreatography (ERCP).

PATIENTS AND METHODS

One hundred six consecutive patients undergoing ERCP (with opacification of the pancreatic duct) at the Helsinki University Central Hospital were included in the study. Patients were tested with a urinary trypsinogen-2 test strip six hours after ERCP. Quantitative trypsinogen-2 as well as serum and urine amylase values were measured before the procedure and six hours after it.

RESULTS

In patients developing pancreatitis after ERCP, the median urinary trypsinogen-2 concentration six hours after the endoscopic procedure was 1780 micrograms/l (range 29-10,700 micrograms/l), and in patients without pancreatitis the median concentration was 3.6 micrograms/l (range 0.1-3390 micrograms/l; P < 0.0001). The sensitivity and specificity figures for the urinary trypsinogen-2 test strip results in diagnosing post-ERCP pancreatitis were comparable (81% and 97%, respectively) to those for serum amylase (91% and 96%) and urine amylase measurements (81% and 95%). The test strip showed a good correlation (kappa = 0.75) with the quantitative trypsinogen-2 assay.

CONCLUSIONS

The increase in urinary trypsinogen-2 concentration after ERCP reflects pancreatic injury, and can be detected by the test strip. Patients should be tested before the ERCP procedure as well, since elevated baseline values occur. The test is reliable and easy to perform even on an outpatient basis. However, its clinical usefulness requires evaluation in further trials.

The expression of prostate-specific membrane antigen in peripheral blood leukocytes

PURPOSE

Prostate-specific membrane antigen (PSM) and prostate-specific antigen (PSA) have been used as marker genes for detection of cancer cells in circulation of prostate cancer patients. However, PSA was recently found to be expressed in non-prostate cell lines and normal blood. To evaluate this phenomenon for PSM, we studied its mRNA expression in non-prostatic cells and cell lines, in blood from healthy donors and patients with prostate cancer.

MATERIALS AND METHODS

We studied PSM expression by a highly sensitive reverse transcription-polymerase chain reaction (RT-PCR) in peripheral blood of 24 patients with cancer of the prostate (CAP) and 13 healthy young male and female donors, in four non-prostatic cell lines and in isolated blood cells. The identity of the RT-PCR product was confirmed by sequencing. Contamination of the samples with cDNA or prostatic RNA was rigorously excluded by subjecting each sample to PCR reaction without RT-enzyme and by RT-PCR with PSA primers, respectively.

RESULTS

We found PSM mRNA expression in blood from 18 of 24 CAP patients and 12 of 13 healthy donors and in the leukocyte fraction of normal blood cells. PSM expression could not be detected in erythroblasts, platelets, K-562, U-937, HL-60 or Jurkat cell lines.

CONCLUSIONS

Our results indicate that sensitive nested RT-PCR method detects PSM mRNA in the leukocyte fraction of normal blood. This "background" expression is probably caused by a leaky promoter of PSM. We conclude that it is necessary to develop quantitative RT-PCR assays to differentiate PSM mRNA expression derived from circulating cancer cells from background expression in blood cells.

Detection of squamous-cell carcinoma antigen-expressing tumour cells in blood by reverse transcriptase-polymerase chain reaction in cancer of the uterine cervix

We used a reverse transcriptase-polymerase chain reaction method for squamous-cell carcinoma (SCC) antigen mRNA to detect circulating tumour cells in patients with carcinoma of the uterine cervix. The sensitivity of the method, as determined by cell spiking experiments, was 10 cultured A431 cells among 10(6) white blood cells. Circulating tumour cells were detected in 6 of 15 patients. In our control group of 24 women, SCC antigen mRNA was detected in 2 pregnant women at term. We followed up the patients for 24 months after sampling and evaluated the outcome. Three out of 6 patients positive for SCC antigen mRNA have relapsed. Additionally, 1 patient has developed breast cancer. In the group of 9 patients negative for SCC antigen mRNA there has been 1 relapse and 1 case of progression of disease. These results suggest that detection of SCC antigen mRNA in peripheral blood by RT-PCR could be useful for staging and evaluation of prognosis in epidermoid carcinoma of the uterine cervix.

Urinary excretion of iohexol as a marker of disease activity in patients with inflammatory bowel disease

BACKGROUND

Increased intestinal permeability of water-soluble contrast medium during an intestinal follow-through is found in patients with active Crohn's disease in the small bowel.

METHODS

Urinary excretion of the water-soluble X-ray contrast medium iohexol was measured after oral administration in patients with inflammatory bowel disease and in healthy controls. The patients were grouped on the basis of disease activity and location and extent of intestinal involvement.

RESULTS

Urinary excretion of iohexol was significantly higher in patients with active disease than in patients with quiescent disease or in healthy controls (P = 0.005), and it correlated positively with activity indices and with the extent of the disease.

CONCLUSION

The intestinal permeability of iohexol is significantly increased in patients with active inflammatory bowel disease in the small bowel and in the colon, whereas the permeability of patients with inactive disease is similar to that in healthy controls. We suggest that urinary excretion of iohexol can be used as a marker of disease activity in patients with inflammatory bowel disease.

Leptin synthesis is resistant to acute effects of insulin in insulin-dependent diabetes mellitus patients

Insulin stimulates ob gene expression and increases serum leptin concentrations in mice and in noninsulin-dependent diabetes mellitus patients. Obese women have higher ob gene messenger ribonucleic acid levels than obese men, suggesting that sex hormones are involved in the regulation of leptin synthesis. We studied the relationship among leptin, insulin, and testosterone in 15 men with insulin-dependent diabetes mellitus (IDDM; age, 29 +/- 2 yr; body mass index, 22.7 +/- 0.5 kg/m2; body fat, 9.5 +/- 1.0%; insulin dose, 44 +/- 4 U/day; hemoglobin A1c, 8.1 +/- 0.3%; diabetes duration, 12.7 +/- 2.0 yr) and 15 healthy control subjects (age, 27 +/- 1 yr; body mass index, 22.6 +/- 0.4 kg/m2; body fat, 9.6 +/- 0.5%) in the fasting state. In addition, the effect of a 4-h euglycemic hyperinsulinemia (approximately 600 pmol/L) on the plasma leptin concentration was determined. The fasting leptin concentration was negatively correlated to plasma testosterone (r = -0.55; P < 0.05) in IDDM patients. The fasting plasma leptin level rose 25% in healthy subjects (from 1.0 +/- 0.2 to 1.3 +/- 0.3 ng/mL; P < 0.05). The leptin levels were higher in IDDM subjects (P < 0.01) and remained unchanged (2.7 +/- 0.2 vs. 2.7 +/- 0.2 ng/mL) during hyperinsulinemia. We reached the following conclusions. 1) In nonobese IDDM patients, leptin synthesis is resistant to the acute effect of insulin. 2) Serum testosterone may contribute to the regulation of leptin synthesis in IDDM patients.

Significance of a single CA 125 assay combined with ultrasound in the early detection of ovarian and endometrial cancer

We evaluated the utility of a single CA 125 measurement in combination with transvaginal sonography for early detection of ovarian and endometrial cancer in asymptomatic postmenopausal women. A sample of peripheral blood was taken from 1291 apparently healthy postmenopausal women, who were examined by conventional and color Doppler ultrasound for early detection of ovarian and endometrial cancer. Serum CA 125 was determined in all samples 3 years later by the IMx CA 125 assay (Abbott Laboratories, Abbott Park, IL). The cutoff level based on the 99th percentile was 30 U/ml. Elevated values were controlled by repeat sonography and an additional determination of CA 125. Record linkage with the files of the Finnish Cancer Registry was performed 3 1/2 years after the primary sonographic screening. The mean CA 125 concentration was 8.1 U/ml (range 0-1410 U/ml). Fourteen of the 1291 women had a CA 125 level greater than 30 U/ml. None of these had signs of either endometrial or ovarian malignancy in the primary sonography screening. Among the other women three cases of endometrial carcinoma (all stage Ib) and one ovarian carcinoma (stage Ia with borderline malignancy) were detected by sonography. All these patients had a CA 125 value <30 U/ml, the mean value being 11.4 U/ml (range 7.5-16.7 U/ml). During follow-up of 3.5 years, one stage Ia ovarian carcinoma, one abdominal carcinomatosis, and two endometrial carcinomas (both stage Ib) were diagnosed. In these patients the mean value for CA 125 was 12.7 U/ml (range 2.5-30.9 U/ml) at the primary sonography screening. A single CA 125 measurement provides no advantage in the early detection of ovarian and endometrial cancer in asymptomatic postmenopausal women compared with transvaginal sonography. The vast majority of women with an elevated CA 125 value have some reason other than an ovarian or endometrial malignancy for this finding.

Pathophysiological importance of various molecular forms of human choriogonadotropin

Human chorionic gonadotropin (hCG), its subunits and fragments are widely used for diagnostic purposes. In addition to the diagnosis of pregnancy and pregnancy related disorders, hCG determinations are used for diagnosis of trophoblastic and recently also nontrophoblastic tumors. The use for diagnosis of nontrophoblastic tumors requires highly specific and ultrasensitive assays. With these, it is possible to measure the concentrations of both hCG, the free beta-subunits and the so called beta-core fragment in healthy subjects. Therefore it is important to establish reference values for these and also to be aware of the influence of physiological factors on the serum and urine concentrations. Improved standardization of the assay methods is also essential for these novel applications of hCG determinations to become useful.

Ectopic pregnancy after in-vitro fertilization is characterized by delayed implantation but a normal increase of serum human chorionic gonadotrophin and its subunits

We studied the dynamics of serum human chorionic gonadotrophin (HCG) and its free alpha (HCG alpha) and beta (HCG beta) subunits in 49 early pregnancies achieved by in-vitro fertilization (IVF) and embryo transfer. Of the 49 early pregnancies, nine were normal singleton pregnancies, 11 were twin pregnancies, 11 were ectopic, eight ended in a clinical (spontaneous) abortion and 10 ended in a preclinical abortion. The HCG, HCG alpha and HCG beta concentrations in serum were measured on days 12, 19 and 26 after embryo transfer. Most ectopic pregnancies could be distinguished from singleton (and twin) pregnancies on the basis of low HCG concentrations by 12 days after embryo transfer, but clinical abortions could not be distinguished from singleton pregnancies. In general, the measurement of HCG alpha and HCG beta and the molar ratios of the various forms provided only marginal additional value to that obtained from HCG, but on days 19 and 26 after embryo transfer HCG alpha was the most sensitive indicator of a normal pregnancy after IVF and embryo transfer. We conclude that in ectopic pregnancies the concentrations of HCG, HCG alpha and HCG beta increase as expected but 1.5 days later than in normal pregnancies. This appears to be the result of a delay in implantation.

Comparison of analysis of the different prostate-specific antigen forms in serum for detection of clinically localized prostate cancer

OBJECTIVES

To compare different forms and ratios of serum prostate-specific antigen (PSA) to determine which form or ratio provides optimal diagnostic specificity and sensitivity in distinguishing between benign prostatic hyperplasia (BPH) and clinically localized prostate cancer.

METHODS

Serum samples were obtained from 47 patients with BPH and 39 with clinically localized prostate cancer. Patients with BPH underwent either transurethral resection of the prostate or transurethral microwave thermotherapy. Patients with prostate cancer, all of whom had no metastases on radionucleotide bone scans and no pelvic lymph node involvement, underwent either radical external beam radiation therapy or radical retropubic prostatectomy. All patients had pretreatment serum PSA levels between 1 and 20 ng/mL. The different forms of serum PSA (free PSA [PSA-F], PSA complexed to alpha 1-antichymotrypsin [PSA-ACT], and total PSA [PSA-T]) were measured using different monoclonal antibodies against PSA and ACT and immunofluorometric assay techniques. Furthermore, three ratios (PSA-F/PSA-T, PSA-ACT/PSA-T, and PSA-F/PSA-ACT) were calculated.

RESULTS

By receiver operating characteristic curve analysis, the performance of the different forms and ratios were compared. The PSA-F/PSA-T ratio had the greatest area under the curve (AUC, 0.776), significantly larger than that for PSA-T (0.612; P = 0.024). For PSA-ACT/PSA-T, the AUC was 0.695 (P = 0.283 versus PSA-T) and 0.773 for PSA-F/PSA-ACT (P = 0.051 versus PSA-T). At a cutoff level < 0.17, PSA-F/PSA-T had a sensitivity of 79%, a specificity of 66%, and a positive predictive value of 66% compared with 74%, 38%, and 50%, respectively, for PSA-T at a cutoff level > 4.0 ng/mL.

CONCLUSIONS

The PSA-F/PSA-T ratio gives the best diagnostic performance compared with that for other forms and ratios of PSA and will reduce the number of prostatic biopsies in patients with BPH.

In vitro stability of free prostate-specific antigen (PSA) and prostate-specific antigen (PSA) complexed to alpha 1-antichymotrypsin in blood samples

OBJECTIVES

To study the in vitro stability of free and complexed forms of prostate specific antigen (PSA) in blood samples in order to establish guidelines for specimen handling, in particular for the clinical utility of the analysis of percentage free PSA.

METHODS

Blood samples were collected and processed to generate serum, heparin plasma, and EDTA plasma. Three different two-site immunoassays were used to measure the concentrations of total PSA (PSA-T), free form of PSA (PSA-F), and PSA-alpha 1-antichymotrypsin complex (PSA-ACT) in order to determine the effect of repeated freezing and thawing, delayed separation of serum from blood cells, and stability during storage at 4 degrees C and 30 degrees C.

RESULTS

Five cycles of freezing and thawing introduced no statistically significant changes in the measured concentrations of PSA-T, PSA-F, or PSA-ACT. The effect of storing blood samples at room temperature for 1-6 h before separation of serum revealed a statistically significant decrease only for PSA-F after 5.5 h of storage (mean decrease 3.5%). PSA-T and PSA-ACT showed good stability in both serum and plasma samples, whereas PSA-F, after 1 week of storage at 4 degrees C, decreased on average by 28.8%, 7.8%, and 5.6%, respectively, in serum, heparin plasma, and EDTA plasma. The decreases of PSA-F at 4 degrees C were statistically significant (P < 0.05) relative to the controls (samples stored at -20 degrees C) after storage for 23 h in serum, 86 h in heparin plasma, and 71 h in EDTA plasma. When the same samples were stored at 30 degrees C for 24 h, only the mean decrease of PSA-F (4.8%) in serum was statistically significant.

CONCLUSIONS

PSA-F in blood samples is less stable than PSA-ACT. It is not advisable to store samples on the clot, especially if time and temperature cannot be controlled. Serum samples should be stored frozen if not analyzed during the same day. After thawing, samples can be stored up to 23 h at 4 degrees C prior to analysis. The use of plasma samples improves the stability of free PSA.

Low-dose oral methotrexate with expectant management of ectopic pregnancy

OBJECTIVE

To investigate recovery times and need for laparoscopy in women with ectopic pregnancy who were treated for 5 days 2.5 mg/day of oral methotrexate or placebo.

METHODS

Sixty women with ectopic pregnancy among patients of an outpatient clinic specializing in early pregnancy disorders were selected for medical treatment in a double-blind, placebo-controlled study. The diagnosis was made by transvaginal sonography and serum hCG determinations, either at admission or after repeated examinations. Women were recruited for the study if they had mild symptoms: the hCG increase was less than 50% within 2 days, the diameter of the ectopic pregnancy was less than 40 mm, there were no signs of intra-abdominal bleeding by transvaginal sonography, and there were no secondary reasons for laparoscopy. Either 2.5 mg of methotrexate or placebo was given orally for 5 days. Serum hCG was determined after 2 days, and hCG, red blood cell count, white blood cell count, platelet count, and serum glutamic-oxaloacetic transaminase were measured; transvaginal sonography was performed after 5 and 12 days. Expectant management was continued individually with check-ups at 1-3-week intervals. Laparoscopy was performed if the patient developed abdominal pain or intra-abdominal hemorrhage, as seen by transvaginal sonography. Statistical analysis was by paired or unpaired t test, Mann-Whitney U test, regression analysis, and repeated measures analysis of variance.

RESULTS

Seventy-seven percent of the patients recovered without the need for laparoscopy in both groups, and there were no significant differences in recovery times or the need for laparoscopy between groups.

CONCLUSION

Oral methotrexate, 2.5 mg for 5 days, does not appear to be more effective than placebo in the treatment of ectopic pregnancy in women eligible for expectant management.

Clinical features of primary ovarian failure caused by a point mutation in the follicle-stimulating hormone receptor gene

The recent finding that a mutation in the FSH receptor gene causes ovarian dysgenesis prompted the present study to determine the phenotype caused by this mutation. Twenty-two patients with ovarian dysgenesis and a 566C-->T mutation in the FSH receptor gene (designated FSH-resistant ovaries or FSHRO) were compared with 30 clinically similar patients with ovarian dysgenesis (designated ODG) who did not have this mutation. The genealogical studies suggested a founder effect of the FSH receptor gene mutation in Finland. Clinically, both groups of patients were characterized by primary or early secondary amenorrhea, variable development of secondary sex characteristics, and high serum levels of FSH and LH. Notable differences were observed in median adult height (FSHRO patients were shorter) and the occurrence of follicles judged by transvaginal sonography (observed in 6 of 8 FSHRO vs. 1 of 11 ODG) and ovarian histology (present in all 9 FSHRO vs. 1 of 4 ODG). These findings suggest that a subset of ovarian dysgenesis patients with the FSH receptor mutation 566C-->T is pathogenetically distinct, possibly due to residual receptor activity, and that these patients can be tentatively identified by demonstrating the presence of ovarian follicles and confirmed by mutation analysis.