The Contribution of Prostatic Acid Phosphatase and Prostatic Specific Antigen in the Diagnosis of Prostatic Cancer

Prostatic acid phosphatase (PAP) and prostatic specific antigen (PSA) were measured by immunochemical methods using test preparations from two different companies. In 66 patients with benign hyperplasia of the prostate a good correlation was found only between PSA levels (orthogonal regression analysis: y = 1.77 x –- 0.68; r = 0.995). Discrimination analysis between benign hyperplasia and new prostatic cancer (28 patients), using ROC curves, revealed a sensitivity for prostatic cancer of about 30 percent using both PAP methods and of about 58 percent using both PSA methods at the 95-percentile of benign hyperplasia. The PSA methods were both more sensitive in detecting prostatic cancer than the PAP methods.

TPS Monitoring in Metastatic Breast Cancer

The management of metastatic breast cancer patients reflects the heterogeneous nature of the disease. While patients may benefit from hormonal treatment, in most cases more toxic chemotherapy is applied in the advanced stages. The pretreatment levels of TPS in patients with metastatic breast cancer are correlated with prognosis. Decreasing TPS levels (>50%) during treatment are indicative of response. The fastest decrease in TPS levels is obtained in patients with a favorable prognosis. Increasing TPS levels (>25%) predict disease progression with a considerable lead time (median 8 months). The clinical impact of these observations is discussed in this paper.

Reference Levels of the Tumor Markers Carcinoembryonic Antigen, the Carbohydrate Antigens 19-9 and 72-4, and Cytokeratin Fragment 19 Using the ®Elecsys Relecsys 1010 Analyzer in a Normal Population in Kuwait. The Importance of the Determination of Local Reference Levels

The tumor markers CEA, CA 19-9, CA 72-4 and CYFRA 21-1 were analyzed in a group of apparently healthy subjects (n=232) in Kuwait using the ®Elecsys Relecsys 1010 analyzer. The distribution of the tumour marker levels was analyzed separately in Kuwaitis (n=103), non-Kuwaitis (n=129), smokers (n=68), non-smokers (n=164), males (n=138) and females (n=94). The distribution of CEA was significantly different in Kuwaitis vs. non-Kuwaitis in the total population (p=0.033) and in non-smokers (p=0.049); in males vs. females in the total population (p<0.0001) and in non-smokers (p=0.0002); and in smokers vs. non-smokers in the total population (p<0.0001) using the non-parametric Mann-Whitney U test. None of the other tumour markers showed significant differences in the subgroups. The upper reference level was defined as the 95th percentile of the normal values in each group. A higher reference level of CEA was observed in smokers (vs. non-smokers) in the total population. Also higher reference levels of CEA were observed in males (vs. females) both in the total population and in non-smokers. In the total population the respective reference levels were: CEA: 4.4 μg/L, CA 19-9: 35 kU/L, CA 72.4: 2.4 kU/L, and CYFRA 21.1: 2.1 μg/L. These results were compared with data in the kit inserts and literature data. The impact of 95th percentiles in a local heterogeneous population is discussed.

[Long-term goals for oral health]

The current, optimistic prognosis is that newborns will reach an average age of 100 years. This increased life-expectancy requires a renewed vision of long-term goals for oral health. The starting-point could be a prospective end-point with minimal oral function which should be reached, for example, in the last years of one's life. The consequence is that adequate oral healthcare for the elderly starts in childhood. Choices such as the extraction of premolars for orthodontic reasons and the dental re-restoration cycle have a great negative impact on reaching this goal. The average sustainability of dental restorations or prosthetic constructions is commonly much shorter than the life-expectancy of a patient. If oral treatment is necessary, it is recommended to give priority to maintaining a minimally functional dentition up to an advanced age, instead offocusing on short- or medium-term goals.

Significance of serum CA125 and TPS antigen levels for determination of overall survival after three chemotherapy courses in ovarian cancer patients during long-term follow-up

PURPOSE OF INVESTIGATION

To evaluate the prognostic significance for overall survival rate for the marker combination TPS and CA125 in ovarian cancer patients after three chemotherapy courses during long-term clinical follow-up.

METHODS

The overall survival of 212 (out of 213) ovarian cancer patients (FIGO Stages I-IV) was analyzed in a prospective multicenter study during a 10-year clinical follow-up by univariate and multivariate analysis.

RESULTS

In patients with ovarian cancer FIGO Stage I (34 patients) or FIGO Stage II (30 patients) disease, the univariate and multivariate analysis of the 10-year overall survival data showed that CA125 and TPS serum levels were not independent prognostic factors. In the FIGO Stage III group (112 patients), the 10-year overall survival was 15.2%; while in the FIGO Stage IV group (36 patients) a 10-year overall survival of 5.6% was seen. Here, the tumor markers CA125 and TPS levels were significant prognostic factors in both univariate and multivariate analysis (p < 0.0001). In a combined FIGO Stage III + FIGO Stage IV group (60 patients with optimal debulking surgery), multivariate analysis demonstrated that CA125 and TPS levels were independent prognostic factors. For patients in this combined FIGO Stage III + IV group having both markers below respective discrimination level, 35.3% survived for more than ten years, as opposed to patients having one marker above the discrimination level where the 10-year survival was reduced to 10% of the patients. For patients showing both markers above the respective discrimination level, none of the patients survived for the 10-year follow-up time.

CONCLUSION

In FIGO III and IV ovarian cancer patients, only patients with CA 125 and TPS markers below the discrimination level after three chemotherapy courses indicated a favorable prognosis. Patients with an elevated level of CA 125 or TPS or both markers after three chemotherapy courses showed unfavorable prognosis.

Tumour markers in colorectal cancer: European Group on Tumour Markers (EGTM) guidelines for clinical use

The aim of this article is to present updated guidelines for the use of serum, tissue and faecal markers in colorectal cancer (CRC). Lack of specificity and sensitivity preclude the use of all existing serum markers for the early detection of CRC. For patients with stage II or stage III CRC who may be candidates for either liver resection or systemic treatment should recurrence develop, CEA should be measured every 2-3 months for at least 3 years after diagnosis. Insufficient evidence exists to recommend routine use of tissue factors such as thymidylate synthase, microsatellite instability (MSI), p53, K-ras and deleted in colon cancer (DCC) for either determining prognosis or predicting response to therapy in patients with CRC. Microsatellite instability, however, may be used as a pre-screen for patients with suspected hereditary non-polyposis colorectal cancer. Faecal occult blood testing but not faecal DNA markers may be used to screen asymptomatic subjects 50 years or older for early CRC.

Definite involuntary childlessness: associations between coping, social support and psychological distress

BACKGROUND

Around 4% of all couples remain involuntarily childless. These people often experience insufficient social support, which further aggravates the distress symptoms such as physical health problems, anxiety, depression and complicated grief. This study investigates the association of coping style and the degree of satisfaction regarding social support from primary support groups with distress symptoms of involuntarily childless individuals.

MATERIALS AND METHODS

Subjects in this cross-sectional study were people who wanted to have children with their partner but were unable to conceive and had acknowledged their involuntary childlessness. The sample consisted of 116 persons (response 88%) with an average age of 39 years (SD = 6.0), with 75% women. The sample group completed a questionnaire consisting of passive and active coping styles from the Utrecht Coping List (UCL), the discrepancy variant of the Social Support List (SSL-D), the short version of the Questionnaire on Experienced Health Complaints (VOEG-21), the Hospital Anxiety and Depression Scale (HADS) and the Inventory of Complicated Grief-Revised (ICG-R), adapted for this study.

RESULTS

Women especially experienced more health complaints, more anxiety and depression symptoms and more complicated grief than the general population. Regression analysis shows that when controlled for sex and the duration of involuntary childlessness, the concepts passive coping style and dissatisfaction with social support were positively associated with health complaints, depression, anxiety and complicated grief. The concept active coping style was negatively associated with depression, anxiety and complicated grief. Explained variance of the different distress symptoms varied from 30 to 65%. A moderating association of perceived social support is only found between a passive coping style and health complaints.

CONCLUSIONS

Psychosocial interventions should be continued after the childlessness has become definite. By teaching couples how to cope actively with their childlessness and how to ask for support, the negative consequences of their childlessness may be decreased.

TPS and CA 19-9 measurements in the follow-up of patients with pancreatic cancer and chronic pancreatitis

The aim of this study was to assess the value of TPS and CA 19-9 in a long-term follow-up analysis of 11 patients with chronic pancreatitis (CP) and 15 patients with pancreatic cancer (PC). In all monitored patients with chronic pancreatitis the initial TPS level was below 200 U/L, whereas CA 19-9 was elevated in two of them. In one patient a dramatic increase in the TPS concentration (820 U/L) was measured at the last follow-up visit (after 8.6 months), which led to the detection of PC. In all patients with PC the preoperative TPS level exceeded 200 U/L, whereas CA 19-9 was elevated in only nine patients. After the Kausch-Whipple operation 11 patients showed no evidence of disease and in eight of these patients both TPS and CA 19-9 were within the reference range; however, in three patients liver metastases were detected after 8-24 months from the last tumor marker measurement. In four of the 15 patients both markers were elevated at the end of the follow-up period and distant metastases were clinically confirmed. Our results indicate that in patients with CP and PC undergoing long-term follow-up, TPS reflects the clinical status of patients more accurately than CA 19-9.

Clinical utility of biochemical markers in colorectal cancer: European Group on Tumour Markers (EGTM) guidelines

In recent years, numerous serum and cell/tissue-based markers have been described for colorectal cancer (CRC). The aim of this article was to provide guidelines for the routine clinical use of some of these markers. Lack of sensitivity and specificity preclude the use of any available serum markers such as carcinoembryonic antigen (CEA), CA 19-9, CA 242, CA 72-4, tissue polypeptide antigen (TPA) or tissue polypeptide-specific antigen (TPS) for the early detection of CRC. However, preoperative measurement of CEA is desirable as this may give independent prognostic information, help with surgical management and provide a baseline level for subsequent determinations. For patients with stage 2 (Dukes' B) and 3 (Dukes' C) disease who may be candidates for liver resection, CEA levels should be measured every 2-3 months for at least 3 years after diagnosis. For monitoring treatment of advanced disease, CEA should also be tested every 2-3 months. Insufficient evidence is presently available to recommend the routine use of other serum markers for monitoring purposes. Similarly, the new cell and tissue-based markers (e.g, ras, P53) cannot yet be recommended for routine clinical use.

[Cantilever resin-bonded bridges with one adhesive surface. A review of the literature]

Conventional resin-bonded bridges are designed with adhesive surfaces on both sides of the dummy. As a consequence both abutment teeth are rigidly connected to each other. Loading of the abutment teeth or dummy will lead to wringing forces in the cement. Adhesive bridges with one adhesive surface are actually cantilever bridges. Theoretically this type of bridges will be less prone to wringing forces due to loading. However, long term research into the performance of cantilever resin-bonded bridges (RBBs) is hardly available. The results of research into the longevity of conventional RBBs differ remarkably between Europe, and the United States and Japan. These difference are discussed in this article. This article compares the fixed-fixed design RBBs with the cantilever RBBs. The differences are discussed based on eight articles, the earliest being published in 1991, which are dedicated, completely or partially, to the subject of cantilever adhesive bridges. One can conclude that in The Netherlands RBBs are wrongly considered to be unreliable. On the contrary, they appear to be reliable and predictable restorations provided their preparations meet the right standards. Although a number of authors conclude that cantilever RBBs are performing better than their fixed-fixed design counterparts in similar situations, further research is needed concerning the longevity of this type of adhesive bridges.

Lateralisation and depth of the internal mammary chain determined by scintigraphy and by ultrasonography: a comparative study in 124 primary breast cancer patients

In 124 primary breast cancer patients the maximum values of the lateralisation of the internal mammary chain (IMC) and their corresponding depths could be determined by scintigraphy and ultrasonography in 77% and 85% of the cases, respectively. With respect to the lateralisation it appeared that these values were uncorrelated between the two methods. With respect to depth correlation was found (correlation coefficient 0.34; P=0.001). We conclude that substantial differences are noted. Irradiation of the IMC based on computed tomography treatment planning might be a better alternative.

Reference levels of the tumor markers carcinoembryonic antigen, the carbohydrate antigens 19-9 and 72-4, and cytokeratin fragment 19 using the Elecsys Relecsys 1010 analyzer in a normal population in Kuwait. The importance of the determination of local reference levels

The tumor markers CEA, CA 19-9, CA 72-4 and CYFRA 21-1 were analyzed in a group of apparently healthy subjects (n=232) in Kuwait using the Elecsys Relecsys 1010 analyzer. The distribution of the tumour marker levels was analyzed separately in Kuwaitis (n=103), non-Kuwaitis (n=129), smokers (n=68), non-smokers (n=164), males (n=138) and females (n=94). The distribution of CEA was significantly different in Kuwaitis vs. non-Kuwaitis in the total population (p=0.033) and in non-smokers (p=0.049); in males vs. females in the total population (p<0.0001) and in non-smokers (p=0.0002); and in smokers vs. non-smokers in the total population (p<0.0001) using the non-parametric Mann-Whitney U test. None of the other tumour markers showed significant differences in the subgroups. The upper reference level was defined as the 95th percentile of the normal values in each group. A higher reference level of CEA was observed in smokers (vs. non-smokers) in the total population. Also higher reference levels of CEA were observed in males (vs. females) both in the total population and in non-smokers. In the total population the respective reference levels were: CEA: 4.4 microg/L, CA 19-9: 35 kU/L, CA 72.4: 2.4 kU/L, and CYFRA 21.1: 2.1 microg/L. These results were compared with data in the kit inserts and literature data. The impact of 95th percentiles in a local heterogeneous population is discussed.

Minimally invasive surgery for solitary parathyroid adenomas in patients with primary hyperparathyroidism: role of US with supplemental CT

PURPOSE

To determine the role of ultrasonography (US) with supplemental computed tomography (CT) in patients with primary hyperparathyroidism who undergo minimally invasive surgery instead of conventional neck exploration.

MATERIALS AND METHODS

US and CT were performed in 61 consecutive patients with primary hyperparathyroidism (part 1) to identify and localize solitary adenomas for resection by means of minimally invasive surgery and to provide a surgical road map. In part 2, involving 33 consecutive patients, CT was performed only when no solitary adenoma was identified with US or for road map information. Minimally invasive surgery was considered successful when serum calcium levels normalized and remained stable.

RESULTS

In part 1, 46 definite solitary adenomas were found with US and two additional ones with CT. Minimally invasive surgery was successful in 45 patients and failed once. In part 2, US helped identify 23 solitary adenomas, and CT helped to find one. Minimally invasive surgery was successful in 22 patients and failed in two. Combined results in 94 patients demonstrated successful minimally invasive surgery in 67 (71%), with 64 of them selected with US alone (95% CI: 61, 80). The sensitivity of US in the diagnosis of solitary adenoma was 78% (95% CI: 67%, 86%), with a positive predictive value of 96% (95% CI: 88%, 99%).

CONCLUSION

US examination of patients with primary hyperparathyroidism allowed successful selection for minimally invasive surgery in more than two-thirds of the cases, with additional CT useful chiefly for surgical road mapping.

The acute effects of norharman on cocaine self-administration and sensorimotor function in male Wistar rats

The purpose of the present study was to determine the acute effects of the beta-carboline norharman on cocaine dependence. Male Wistar rats were allowed to self-administer cocaine for 3 h for seven sessions. A single injection of norharman (0.2-20 mg/kg, i.p.) was given 30 min before the onset of the seventh session. It was shown that norharman decreased the cocaine intake in a U-shaped manner with the dose of 10 mg/kg having the most potent effect. These results indicate that several receptor mechanisms mediate the effects of norharman. In addition, 15 min following the administration of norharman on session 7, motor and sensory skill tests were performed. Six naïve animals were tested with the dose, which has the most pronounced effect on cocaine self-administration intake, in order to examine whether the observed effects were due to norharman or due to the combination of norharman and cocaine. It was observed that norharman in both the naïve and cocaine-exposed animals significantly increased the response time in the somato-sensory orienting test. However, only in the naïve animals a significant effect of norharman on the grasp reflex was observed.

Immunohistochemical profiles of 30 monoclonal antibodies against cytokeratins 8, 18 and 19. Second report of the TD5 workshop

In the first report of the TD5 workshop (TD5-1), the epitope specificities of 30 different monoclonal antibodies against cytokeratins 8, 18 and 19 were determined. This second report presents the immunohistochemical profiles of these antibodies using human appendix and normal skin for evaluation. Each antibody was tested by one or two different laboratories recruited from the Dutch Working Group on Immunohistochemistry and Cytochemistry. Eight different laboratories participated. The histological specimens were pretreated by the participants in three different ways for immunohistochemistry: microwave antigen retrieval in citrate buffer, enzymatic digestion to restore epitope exposure, no specific treatment (untreated paraffin-embedded samples), and tested blindly without knowledge of cytokeratin or epitope specificity of the antibodies at three different concentrations of 50, 10 and 1 microg/ml. Most of the tested antibodies (29/30) were useful in at least one pretreatment method, with microwave antigen retrieval being the most sensitive approach. For some antibodies, very high backgrounds were observed. Furthermore, it can be concluded that 11 MAbs performed well using all three staining protocols, including untreated paraffin-embedded sections. Interestingly, all the antibodies with documented selected specificity towards cytokeratin 8 (i.e. 178, 191, 199, 202 and 206) are reactive with an immunodominant region corresponding to amino acids 340-365 on cytokeratin 8, which evidently is well-suited as target for immunohistochemical interactions. Similarly, three antibodies with the same capacity to react with untreated samples had specificity against cytokeratin 19 (i.e. 179, 197 and 204) in the corresponding region in this filament, i.e. amino acids 311-335, or the KS 19.1 epitope. None of the six antibodies against the other major cytokeratin 19 epitope (BM 19.21) were found useful for immunohistochemistry on untreated samples. The overall conclusions from the present investigation are that all cytokeratin-8-specific antibodies with defined epitope specificities were very useful. Only one of the major two epitopes on cytokeratin 19 seems to be available for efficient immunohistochemistry. Cytokeratin 18 exposes some epitopes outside the immunodominant region reactive with the antibodies 190, 203 and 205 which can be used for untreated samples. The implications of these findings are of significance both for diagnostic histopathology and for the biology of tumor marker epitope expression in tissues.

Prognostic significance of CA 125 and TPS levels after 3 chemotherapy courses in ovarian cancer patients

OBJECTIVE

To evaluate the prognostic significance of and predictive value for survival of CA 125 and TPS levels after three chemotherapy courses in ovarian cancer patients.

METHODS

We analyzed in a prospective multicenter study the 1- and 2-year overall survival (OS) in ovarian carcinoma patients. The prognostic significance of CA 125 and TPS levels above the discrimination value (25 kU/L and 100 U/L, respectively) was examined by univariate and multivariate analyses.

RESULTS

Of the 213 cases included, 64 patients were staged as FIGO I + II and 149 patients were staged as FIGO III + IV. Tumor marker levels in stage I + II were not correlated with survival. However, stage III and IV patients with elevated levels of CA 125 or TPS after three chemotherapy courses had a worse 2-year OS (69% vs 26%, P < 0.0001 and 57% vs 20%, P < 0.0001, respectively) than patients with normal levels of the markers. In univariate analysis the result of operation (staging laparatomy and partial debulking) and advanced FIGO stage (IV) were also adverse prognostic factors. Independent factors predictive of low 2-year OS by multivariate analysis were staging laparotomy, TPS elevated, and CA 125 elevated. The only factors predictive of low 1-year OS were TPS elevated and staging laparotomy.

CONCLUSIONS

Ovarian cancer patients with elevated CA 125 levels after three chemotherapy courses have a poor prognosis. However, the prognostic accuracy can be significantly increased by the parallel determination of serum TPS.

Epitope specificity of 30 monoclonal antibodies against cytokeratin antigens: the ISOBM TD5-1 Workshop

The epitope specificities of 30 monoclonal antibodies (MAbs) against the most common human cytokeratins. i.e., Nos. 8, 18, and 19, in epithelial cells were investigated in the ISOBM TD-5 Workshop. Seven research groups from universities or companies participated independently in the evaluation of the antibody specificities. The complex assembly of cytokeratins in vivo, with obligatory heterologous dimeric combinations of different cytokeratins from each of the two major groups, comprising together more than 20 different individual cytokeratins, made analysis of the antibody reactivity patterns with isolated single cytokeratins necessary. The concordance of the evaluations was striking and independent of the technologies used. As antigens purified individual cytokeratins, chemically degraded purified cytokeratins, recombinant intact and truncated cytokeratins, as well as specific synthesized shorter peptides were used. In order to elucidate the epitope specificity, reactivity patterns in ELISA assays and immunoblots with partial enzymatic degradation of the antigens were performed. Competitive cross-inhibition experiments between antibodies using antigens and antibodies in all possible combinations were performed with radioimmunometric assays, BIAcore, and ELISA technology. All 30 antibodies could convincingly be classified with regard to target cytokeratin. One MAb (192) had to be deleted due to dual specificities in both isotype and epitope specificity against its target. Six antibodies bound selectively to cytokeratin 8, 14 to cytokeratin 18, and 10 to cytokeratin 19, as demonstrated by using native, recombinant, and synthesized antigens. The immunodominant part of the molecule for all three types of cytokeratins was located in the region of amino acid (aa) 270-400. Out of the six MAbs reactive with cytokeratin 8, four MAbs, i.e., 178, 199, 202, and 206, were reactive with a sequence in the interval aa 340-365, and MAb 191 reacted with a closely related epitope. The remaining antibody, 192, presented dual specificities. At least two closely related major immunogenic epitopes could be identified in cytokeratin 8. In cytokeratin 18 four distinct epitopes could be documented, again with the dominating sequence region 270-429 as target for 10 (181, 184, 186, 188, 189, 190, 193, 196, 198, and 200) out of 14 antibodies. Since MAb 193 is known to react with the M3 epitope, aa 322-342 in cytokeratin 18, this entire group is reactive in the region close to the charge shift, in the middle of the rod 2B region, as shown by competitive binding. The remaining four anticytokeratin 18 antibodies (180, 185, 203, and 205) displayed unique, noncompetitive binding to this filament. Cytokeratin 19, reactive with altogether ten antibodies, displayed two major epitopes, all of them also within the large immunodominant region. MAbs 179, 195, 197, and 204 were reactive with the peptides aa 311-335 also known as the KS 19.1 epitope, and MAbs 182, 183, 187, 194, and 201 bound to peptide aa 346-367, known as the BM 19.21 epitope. One antibody, 231, was selectively reactive with aa 356-370 in cytokeratin 19. A complex pattern of binding specificities comprising at least ten different, noncompetitive epitopes, mainly situated in the rod portion, 2A and 2B, situated close to the charge shift in the rod of all three cytokeratins was documented. Out of the 29 classifiable antibodies, altogether 22 were reactive in this very short region, i.e., from aa 311 to 370 in all cytokeratin filaments. The remaining seven antibodies displayed unique binding properties. The implications of the findings are of significance both for immunohistochemistry and for assaying circulating heterodimeric, partially degraded complexes in patients' blood for tumor marker evaluation.

Efficient membrane assembly of the KcsA potassium channel in Escherichia coli requires the protonmotive force

Very little is known about the biogenesis and assembly of oligomeric membrane proteins. In this study, the biogenesis of KcsA, a prokaryotic homotetrameric potassium channel, is investigated. Using in vivo pulse-chase experiments, both the monomeric and tetrameric form could be identified. The conversion of monomers into a tetramer is found to be a highly efficient process that occurs in the Escherichia coli inner membrane. KcsA does not require ATP hydrolysis by SecA for insertion or tetramerization. The presence of the proton-motive force (pmf) is not necessary for transmembrane insertion of KcsA; however, the pmf proved to be essential for the efficiency of oligomerization. From in vivo and in vitro experiments it is concluded that the electrical component, deltapsi, is the main determinant for this effect. These results demonstrate a new role of the pmf in membrane protein biogenesis.

Tissue polypeptide specific antigen (TPS), a marker for differentiation between pancreatic carcinoma and chronic pancreatitis. A comparative study with CA 19-9

BACKGROUND

The value of serum tissue polypeptide specific antigen (TPS) as a complement to CA 19-9 in the detection of pancreatic carcinoma was determined prospectively. TPS and CA 19-9 levels obtained at the time of diagnosis in patients suspected of having chronic pancreatitis or pancreatic carcinoma were evaluated in receiver operating characteristic (ROC) curve analysis.

METHODS

Serum TPS and CA 19-9 levels were measured by immunoassays in 122 subjects, 48 with pancreatic carcinoma and 74 with chronic pancreatitis.

RESULTS

Elevated levels of CA 19-9 were detected preoperatively in 70% of pancreatic carcinoma patients and in 19% of chronic pancreatitis patients. Elevated levels of TPS were detected in 100% of patients with pancreatic carcinoma and in 22% of patients with chronic pancreatitis. The median levels of TPS and CA 19-9 for pancreatic carcinoma were significantly higher than those for chronic pancreatitis (P < 0.0001). Increasing the upper reference value of TPS allowed for better discrimination between chronic pancreatitis and pancreatic carcinoma. ROC curve analysis showed that the introduction of 200 U/L as a decision criterion for TPS did not reduce its sensitivity but significantly improved its specificity. At a specificity of 98% for TPS, discrimination between pancreatic carcinoma and chronic pancreatitis was found to be 97%. Increasing the upper reference level for CA 19-9 to attain a specificity of 98% decreased its sensitivity from 70% to 33%.

CONCLUSIONS

At an elevated cut-off level for TPS (200 U/L), almost complete discrimination between pancreatic carcinoma and chronic pancreatitis was obtained. TPS will be more useful than CA 19-9 in the differential diagnosis of pancreatic carcinoma and chronic pancreatitis.

Tissue polypeptide specific antigen (TPS), a marker for differentiation between pancreatic carcinoma and chronic pancreatitis. A comparative study with CA 19-9

BACKGROUND

The value of serum tissue polypeptide specific antigen (TPS) as a complement to CA 19-9 in the detection of pancreatic carcinoma was determined prospectively. TPS and CA 19-9 levels obtained at the time of diagnosis in patients suspected of having chronic pancreatitis or pancreatic carcinoma were evaluated in receiver operating characteristic (ROC) curve analysis.

METHODS

Serum TPS and CA 19-9 levels were measured by immunoassays in 122 subjects, 48 with pancreatic carcinoma and 74 with chronic pancreatitis.

RESULTS

Elevated levels of CA 19-9 were detected preoperatively in 70% of pancreatic carcinoma patients and in 19% of chronic pancreatitis patients. Elevated levels of TPS were detected in 100% of patients with pancreatic carcinoma and in 22% of patients with chronic pancreatitis. The median levels of TPS and CA 19-9 for pancreatic carcinoma were significantly higher than those for chronic pancreatitis (P < 0.0001). Increasing the upper reference value of TPS allowed for better discrimination between chronic pancreatitis and pancreatic carcinoma. ROC curve analysis showed that the introduction of 200 U/L as a decision criterion for TPS did not reduce its sensitivity but significantly improved its specificity. At a specificity of 98% for TPS, discrimination between pancreatic carcinoma and chronic pancreatitis was found to be 97%. Increasing the upper reference level for CA 19-9 to attain a specificity of 98% decreased its sensitivity from 70% to 33%.

CONCLUSIONS

At an elevated cut-off level for TPS (200 U/L), almost complete discrimination between pancreatic carcinoma and chronic pancreatitis was obtained. TPS will be more useful than CA 19-9 in the differential diagnosis of pancreatic carcinoma and chronic pancreatitis.

Tissue polypeptide specific antigen (TPS), a marker for differentiation between pancreatic carcinoma and chronic pancreatitis. A comparative study with CA 19-9

BACKGROUND

The value of serum tissue polypeptide specific antigen (TPS) as a complement to CA 19-9 in the detection of pancreatic carcinoma was determined prospectively. TPS and CA 19-9 levels obtained at the time of diagnosis in patients suspected of having chronic pancreatitis or pancreatic carcinoma were evaluated in receiver operating characteristic (ROC) curve analysis.

METHODS

Serum TPS and CA 19-9 levels were measured by immunoassays in 122 subjects, 48 with pancreatic carcinoma and 74 with chronic pancreatitis.

RESULTS

Elevated levels of CA 19-9 were detected preoperatively in 70% of pancreatic carcinoma patients and in 19% of chronic pancreatitis patients. Elevated levels of TPS were detected in 100% of patients with pancreatic carcinoma and in 22% of patients with chronic pancreatitis. The median levels of TPS and CA 19-9 for pancreatic carcinoma were significantly higher than those for chronic pancreatitis (P < 0.0001). Increasing the upper reference value of TPS allowed for better discrimination between chronic pancreatitis and pancreatic carcinoma. ROC curve analysis showed that the introduction of 200 U/L as a decision criterion for TPS did not reduce its sensitivity but significantly improved its specificity. At a specificity of 98% for TPS, discrimination between pancreatic carcinoma and chronic pancreatitis was found to be 97%. Increasing the upper reference level for CA 19-9 to attain a specificity of 98% decreased its sensitivity from 70% to 33%.

CONCLUSIONS

At an elevated cut-off level for TPS (200 U/L), almost complete discrimination between pancreatic carcinoma and chronic pancreatitis was obtained. TPS will be more useful than CA 19-9 in the differential diagnosis of pancreatic carcinoma and chronic pancreatitis.

Direct, minimally invasive adenomectomy for primary hyperparathyroidism: An alternative to conventional neck exploration?

OBJECTIVE

To evaluate the feasibility and efficacy of a direct, minimally invasive adenomectomy (MIA) as an alternative to conventional neck exploration (CNE) in patients with primary hyperparathyroidism.

SUMMARY BACKGROUND DATA

Because primary hyperparathyroidism is caused by a solitary adenoma in 85% to 90% of patients, a direct adenomectomy through a mini-incision would theoretically suffice whenever an adenoma is correctly localized on preoperative imaging. If effective, a less invasive method could spare the patient an unnecessary bilateral neck exploration, thus saving time and rendering future surgical procedures in the neck less problematic.

METHODS

Between October 1994 and October 1998, 110 consecutive patients with biochemically proven primary hyperparathyroidism who were to undergo surgery were enrolled in this study. Ultrasound and spiral CT were routinely performed as standard preoperative imaging modalities in the first series of 65 patients. In the second series of 45 patients, ultrasound was performed as the sole initial modality; it was supplemented by CT only in case of inconclusive test results. If test results were unequivocal (one adenoma), the patient was offered MIA. CNE was performed if the results were equivocal or if multiglandular disease was suspected.

RESULTS

Overall, 84 patients were selected for MIA and 26 for CNE. In the first series, 2 MIA procedures (2/51) were converted to CNE because of negative perioperative findings. All 65 procedures resulted in normocalcemia. In the second series, all but five (4/33 MIAs, 1/12 CNEs) resulted in normocalcemia. A reexploration (CNE) was performed in three patients, resulting in normocalcemia after resection of a second or third adenoma. Two patients are still awaiting reexploration. In both series together, 78 of the 110 patients were successfully treated with MIA and spared CNE.

CONCLUSION

MIA is a safe and effective alternative to CNE that may replace CNE in approximately two thirds of all patients.

Delta psi stimulates membrane translocation of the C-terminal part of a signal sequence

For several proteins in Escherichia coli it has been shown that the protonmotive force (pmf) dependence of translocation can be varied with the signal sequence composition, suggesting an effect of the pmf on the signal sequence. To test this possibility, we analyzed the effect of the membrane potential on translocation of the signal sequence. For this purpose, a precursor peptide was used (SP+7), corresponding to the signal sequence of PhoE with the first seven amino acids of the mature part that can be processed by purified leader peptidase. Translocation was studied in pure lipid vesicles containing leader peptidase, with its active site inside the vesicles. In the presence of a positive inside Delta psi, the amount of processing of SP+7 was significantly higher than without a Delta psi, indicating that the translocation of the cleavage region is stimulated by Delta psi. Replacement of the helix-breaking glycine residue at position -10 in the signal sequence for a leucine abolished the effect of Delta psi on the translocation of the cleavage region. It is concluded that Delta psi directly acts on the wild type signal sequence by stimulating the translocation of its C terminus. We propose that Delta psi acts on the signal sequence by stretching it into a transmembrane orientation.

Prognostic significance of CA 125 and TPS levels after chemotherapy in ovarian cancer patients

The analysis of survival data of patients with epithelial ovarian cancer proved that both CA 125 and TPS were good markers for clinical outcome prediction. Patients receiving chemotherapy were analyzed for 2-year overall survival (OS). Kaplan-Meier survival analysis showed highly significant differences in OS between patients with stage I+II (survival for 2 years 68%) and stage III+IV (survival for 2 years 33%; p = 0.0008). CA 125 levels above or below 35 kU/I and TPS levels above or below 80 U/l after 3 chemotherapy courses were not significantly correlated with OS in stage I+II patients (p = 0.06 respectively 0.07). However, in the subgroup of patients with stage III+IV the cut-off levels of CA 125 and TPS were excellent discriminators of OS: With CA 125 levels below the cut-off 52% of the patients survived, while with CA 125 levels above the cut-off only 13% survived (p < 0.0001). With TPS levels below the cut-off 49% of the patients survived, while with levels above the cut-off only 19% of the patients survived (p < 0.0001). In the subset of patients with CA 125 levels less than 35 kU/I after 3 chemotherapy courses (n = 50) analysis of their TPS levels allowed further discrimination of the prognostic significance. With TPS levels below the cut-off 63% of the patients survived, while 35% of the patients survived with TPS levels above the cut-off. The sum value of CA 125 and TPS cut-off values (115) as discriminator correlated even better with survival rate: With levels below this sum value 63% of the patients survived, while this was only 17% with sum values above the summed cut-off level (p = 0.0004). The extent to which the tumor was removed at operation also correlated with the 2 years survival rate. None of the patients with a staging laparotomy (n = 10) showed a 2-years survival. The difference in OS between patients with complete debulking and partial debulking was significant: OS 51% versus 23% (p = 0.027). Prognosis was not significantly correlated with histological type.

BR-MA, OM-MA, GI-MA and CEA: clinical evaluation using the IMMULITE analyzer

This study was designed to clinically evaluate four tumour markers on the automated chemiluminescent immunoanalyser, IMMULITE, and to compare the data obtained with those of established immunoassays. IMMULITE BR-MA and CEA were compared to the CIS ELSA CA 15-3 and either the CIS CEA-ENZELSA or TOSOH (AIA 1200) CEA in 206 serum samples from 32 breast cancer patients. A parallel reaction was mainly observed between BR-MA and CA 15-3 assays which accorded well with the clinical situation. BR-MA was more sensitive in both progressive disease and stable disease than CA 15-3. Data from the CEA assays gave a parallel response in individual patients, but the sensitivity was lower compared to BR-MA/CA 15-3. IMMULITE OM-MA was compared to CIS ELSA CA 125 in 208 sera from 32 longitudinally followed ovarian cancer patients. In the majority of patients, a parallel response was observed; lower values were found with the OM-MA assay, but no clinical discrepancies were noted. IMMULITE GI-MA and CIS ELSA CA 19-9 were evaluated in 17 colorectal cancer patients (47 serum samples). In most of the patients, the data pattern was parallel, and differences in the absolute values were only observed in a few instances. In conclusion, the IMMULITE assays corresponded well with established methods, and the data obtained support their use in the management of cancer patients.

Serotoninergic status in patients with hereditary vascular retinopathy syndrome

AIM/BACKGROUND

In a new autosomal dominant syndrome (which the authors called hereditary vascular retinopathy (HVR)) cerebral ischaemia, Raynaud's phenomenon, and migraine are the most striking features. As serotonin (5-HT) is known to play a role in vasospastic processes, Raynaud's phenomenon, and migraine they wondered whether the serotoninergic status in patients with HVR is different. Therefore, it was decided to investigate some serotoninergic variables in these patients.

METHODS

The study was conducted in 12 patients with HVR, 10 relatives, and 19 healthy controls. The levels of intraplatelet and plasma 5-HT were measured, as well as the plasma levels of its precursor amino acid tryptophan and the ratio of tryptophan to the large neutral amino acids, which compete with the transport of tryptophan through the blood-brain barrier.

RESULTS

In both the patients with HVR and in nine relative the concentrations of 5-HT in plasma and platelets were significantly lower than in controls. The plasma levels of tryptophan and the tryptophan ratio were also found to be lower in the patient group compared with the control group, but not in the relatives.

CONCLUSION

The observed alterations in 5-HT and its precursor tryptophan strongly suggest the existence of a malfunctioning of the serotoninergic system in the HVR syndrome.

The current role of high-resolution ultrasonography of the hand and wrist in rheumatic diseases

OBJECTIVE

To assess the current role of ultrasound in the diagnosis and treatment of pathological changes in the wrist and hand.

METHODS

39 patients (14 male and 25 female, mean age 35 yrs.) with ill-defined pain and/or swelling of the wrist or hand were examined using a high-definition ultrasound (US) instrument.

RESULTS

18 patients had tenosynovitis, which in one patient was due to a previously unsuspected foreign body. 10 patients had arthritis involving the wrist and 5 the fingers; 2 patients had a ganglion; one had a neuroma of the median nerve and one patient with a previous tenorrhaphy suffered from the recurrent rupture of this tendon. Two patients had carpal tunnel syndrome, one due to tenosynovitis and one due to the formation of a post-operative fibrotic sheath around the median nerve. 7 patients with synovitis of the wrist underwent US-guided synovial biopsy. 12 patients with tenosynovitis and 6 with arthritis received injections of corticosteroids plus anaesthetic under US-guidance. The spreading of the steroid crystals around the tendon and throughout the joint could be easily monitored. No complications were encountered.

CONCLUSION

High-definition ultrasound is a valuable technique for the imaging of pathologic changes of the wrist and hand and for injection therapy.

The orientation of nisin in membranes

Nisin is a 34 residue long peptide belonging to the group A lantibiotics with antimicrobial activity against Gram-positive bacteria. The antimicrobial activity is based on pore formation in the cytoplasmic membrane of target organisms. The mechanism which leads to pore formation remains to be clarified. We studied the orientation of nisin via site-directed tryptophan fluorescence spectroscopy. Therefore, we engineered three nisin Z variants with unique tryptophan residues at positions 1, 17, and 32, respectively. The activity of the tryptophan mutants against Gram-positive bacteria and in model membrane systems composed of DOPC or DOPG was established to be similar to that of wild type nisin Z. The tryptophan fluorescence emission maximum showed an increasing blue-shift upon interaction with vesicles containing increased amounts of DOPG, with the largest effect for the 1W peptide. Studies with the aqueous quencher acrylamide showed that all tryptophans became inaccessible from the aqueous phase in the presence of negatively charged lipids in the vesicles. From these results it is concluded that anionic lipids mediate insertion of the tryptophan residues in at least three positions of the molecule into the lipid bilayer. The depth of insertion of the tryptophan residues was determined via quenching of the tryptophan fluorescence by spin-labeled lipids. The results showed that the depth of insertion was dependent on the amount of negatively charged lipids. In membranes containing 50% DOPG, the distances from the bilayer center were determined to be 15.7, 15.0, and 18.4 A for the tryptophan at position 1, 17, and 32, respectively. In membranes containing 90% DOPG, these distances were calculated to be 10.8, 11.5, and 13.1 A, respectively. These results suggest an overall parallel average orientation of nisin in the membrane, with respect to the membrane surface, with the N-terminus more deeply inserted than the C-terminus. These data were used to model the orientation of nisin in the membrane.

Successful minimally invasive surgery in primary hyperparathyroidism after combined preoperative ultrasound and computed tomography imaging

The hypothesis that due to the high prevalence of solitary adenoma and the accuracy of modern imaging techniques it should be possible to cure a considerable number of patients by direct adenomectomy through a minimally invasive approach was tested in a consecutive series of 66 patients with primary hyperparathyroidism. Preoperative parathyroid imaging consisted of a combination of (Doppler) ultrasound and spiral computed tomography with cine-loop reconstruction potentiality. If only one parathyroid adenoma was identified preoperatively, a minimally invasive approach was advised. If more than one adenoma was located, or when the imaging results were equivocal, the patient was advised to undergo a conventional bilateral neck exploration. Sixty-six patients (54 female, 12 male) with a median age of 60 years and a median serum calcium of 2.90 mmol L(-1) were studied. Fifty-one of these patients underwent minimally invasive surgery, which was successful in 49 patients, while conversion to conventional neck exploration was necessary in two patients. Conventional neck exploration was chosen for the other 15 patients. Six of these proved to have multiglandular disease or a retro-sternal adenoma, while in nine patients only one parathyroid adenoma was found. All patients became normocalcaemic postoperatively. Morbidity consisted of a transient unilateral vocal cord paralysis in one patient. These results support the original hypothesis: successful minimally invasive surgery was possible in 74% (49 of 66) of patients, thus avoiding conventional neck exploration. This strategy further simplifies the operative treatment of primary hyperparathyroidism without loss of efficiency.

The diagnostic accuracy of core biopsy in palpable and non-palpable breast lesions

OBJECTIVE

To assess the accuracy of large-core needle biopsy in evaluating palpable and nonpalpable breast lesions.

METHODS AND PATIENTS

Stereotaxic and ultrasound (US) guided core biopsies were performed in 103 breast lesions in 97 patients. Subsequently, all patients underwent surgery. All specimens (core biopsy and surgical) underwent radiography for evaluation of microcalcifications. The histopathologic findings of the core biopsies and the surgical specimens were correlated.

RESULTS

Core biopsies and surgery findings were concordant in 100% of the 27 palpable lesions and in 89% of the 76 nonpalpable lesions. One case of malignancy, ductal carcinoma in situ (DCIS), was not diagnosed by core biopsy. In 102 (99%) of the 103 breast lesions, a correct choice for additional diagnostic procedure or definitive treatment could have been made upon histopathologic findings of core biopsy.

CONCLUSION

Stereotaxic and ultrasound-guided core biopsy are safe, reliable and less traumatic than excisional biopsy. Special attention is necessary when atypical ductal hyperplasia (ADH) or DCIS without invasive carcinoma is found. Radiography of the biopsy specimens for detection of microcalcifications is essential.

Ultrasound guided synovial biopsy of the wrist

Seven patients (4 female and 3 male, mean age 46) with arthritis of the wrist (n = 7) without known etiology were evaluated. High-definition ultrasound equipment was used for localization of synovial hypertrophy, suitable for ultrasound guided biopsy without risk. A 18-gauge diameter Tru-cut biopsy needle was used in an automated gun. Two passes were performed with continuous guidance of the needle-tip. In all patients representative synovial tissue was obtained in adequate amount. No complications were encountered. Ultrasound guided biopsy is proposed as an effective technique which can be performed with low patient discomfort on an outpatient basis.

[Digital roentgen-guided large-needle biopsy as an alternative to surgical biopsy in patients with nonpalpable mammographic abnormalities]

OBJECTIVE

To compare histopathological findings from stereotaxic needle core biopsies and from excision biopsies performed on patients with impalpable breast lesions suggestive of carcinoma.

DESIGN

Prospective and descriptive, with a description of the stereotaxic needle core biopsy procedure.

SETTING

Academic Hospital Utrecht, the Netherlands.

METHODS

In 36 patients core biopsies were done with 14-gauge biopsy needles, followed by a localisation procedure with surgical biopsy. The pathological features of the core and excision specimens were compared.

RESULTS

Results of 35 (97%) core biopsies corresponded to those of excision biopsies. Stereotaxic core biopsy was not possible due to technical problems in 2 cases.

CONCLUSION

Stereotaxic core biopsy appears to be an acceptable alternative to excision biopsy.

Significance of cytokeratin markers TPA, TPA (cyk), TPS and CYFRA 21.1 in metastatic disease

Tissue polypeptide antigen has been advocated over the past two decades as a serum tumour marker. It was a long time before it was proven that these proteins in the serum are related to cytokeratin fragments. In this study the different behaviour of the test systems TPA, TPS, TPA(cyk) and CYFRA 21.1 were investigated in serum samples, mainly of metastasized cancer patients. By selecting individual samples with a high and a low TPA/TPS ratio it could be proven that no correlation existed in these samples between TPS (determining fragments of cytokeratin 18) and CYFRA 21.1 (determining fragments of cytokeratin 19). On the contrary, a good correlation was established between the TPA test and the CYFRA 21.1 test, and intermediate correlations were present between these tests and TPA (cyk). The TPA (cyk) test determines cytokeratin 8 and 18 fragments. During therapy, monitoring of metastasized patients with these tests could show a different pattern of reactivity. It is concluded that the different test results during therapy monitoring are not always easy to interpretate. The release of cytokeratins from cancer cells needs further study.

New markers for breast carcinoma-associated antigen in comparison with CA 15-3

The objective of this study was the clinical comparison of newly developed antibodies used in commercially available test systems with CA 15-3 (CIS bio international). IMMULITE BR-MA is a sequential chemoluminescent assay using the Mab's Ma552 and Ma695. Truquant BR RIA is a competitive inhibition radioimmunoassay using the Mab B27.29. ELSA-CA 15-3 is a sequential immunoradiometric assay using the Mab's115D8 and DF3. In the study 32 breast cancer patients (206 serum samples) were included during therapy monitoring. Linear regression analysis was performed with the CA 15-3 test as the reference method. Clinical criteria of response were according to UICC). Regression analysis in the range 0-1000 kU/l revealed the equations: IMMULITE = 1.65CIS + 0.87 (r = 0.78) and Truquant = 1.16 CIS + 10.6 (r = 0.95). The upper reference level of normal controls were somewhat higher than using the CIS method (30 kU/l): IMMULITE and TRUQUANT 40 kU/l and 36 kU/l, respectively. In all patients (except in 1 serum sample) nearly complete parallel tumour marker changes were seen with only minimal discrepancies in a few patients. However, the average factor between different patients varied between 0.51-6.9 (IMMULITE) and 0.74-2.3 (Truquant). In comparison to UICC criteria no discrepancies were observed. Therefore, we concluded that the test systems from DPC and BIOMIRA for the CA 15-3 antigen can replace the CIS test. Patient results were not interchangable. All test systems followed the clinical course of the disease in the same way.

A multicentre evaluation of tumour marker determinations using the automatic Enzymun-Test Systems ES 300 and ES 600/700

A multicentre evaluation of the determination of carcinoembryonic antigen (CEA), the cancer antigens CA 15-3, CA 19-9, CA 72-4 and CA 125 (II generation), the cytokeratin 19 marker Cyfra 21-1 and alpha-foetoprotein (AFP) using the Enzymun-Test System (ES 300 and ES 600/700) was performed in 23 laboratories. The tumour markers were measured in a total of 4266 human serum samples. The intra-assay precision was less than 5% in 80% of all serum samples investigated and in 95% of the serum samples at or above the cut-off level of the tumour markers. Inter-assay precision was less than 10% in 86% of the marker determinations. The interlaboratory survey also showed high reproducibility for the determination of all the tumour markers. In 3 laboratories the results of CA 15-3 in 283 serum samples were compared with the IRMA method of CIS bio international. The regression coefficient, r, was 0.967. In 4 laboratories the results of CEA in 312 samples were compared with the results obtained on the IMx analyser. The regression coefficient, r, was 0.967. In benign gynaecological diseases, CA 125 (II) was most frequently elevated in endometriosis. In gastrointestinal diseases it was proven that CEA is still the marker with the highest sensitivity as compared with CA 19-9 and CA 72-2 (59% with healthy controls as the reference group and 44% with patients having benign gastrointestinal disease as the control group). In pancreatic cancer CA 19-9 showed the highest sensitivity (78% and 62% respectively). In gastric cancer the three markers did not show statistically different results. When the gastric cancer patients were divided according to stage, CA 72-4 appeared to be more sensitive than CA 19-9 only in stage IV.

[Favorable results of minimally invasive surgery in the treatment of primary hyperparathyroidism]

OBJECTIVE

To study the appropriateness of minimally invasive surgical treatment of primary hyperparathyroidism.

DESIGN

Prospective.

SETTING

University Hospital Utrecht, the Netherlands.

METHOD

In patients with primary hyperparathyroidism, parathyroid adenomas were located preoperatively by means of Doppler assisted ultrasonography and spiral computer tomography. If the results were positive, minimally invasive surgery was performed.

RESULTS

Minimally invasive surgery was carried out in 13 out of 15 successive patients with good results (the serum calcium and parathyroid hormone levels returned to normal). Two patients were subjected to conventional neck exploration, also with good results (preoperatively several adenomas were suspected in one, while no adenoma was seen in the other).

CONCLUSION

It can be calculated that minimally invasive surgery will probably suffice in 60-70% of the patients with primary hyperparathyroidism, so that conventional neck exploration can be avoided.

Electronic portal imaging

In our institute, we have developed an electronic portal imaging system based on a matrix of 256 x 256 ionisation chambers. By improvements to the electronics, the system produces images with the same quality as the original system but 3-10 times faster. Software for automatic image analysis has been applied to more than 10,000 images over the last two years. Using an off-line correction strategy, the systematic patient set-up error has been limited to 5 mm or less for 98% of the patients treated for prostate cancer.

How to integrate serum tumor markers into clinical oncologic practice

Several serum tumor markers have been studied in different types of epithelial cell-associated cancer. The application of these markers in clinical oncologic practice is hampered by insufficient sensitivity and specificity in most primary tumors. It is important to define which markers contribute to patient management. Prostate-specific antigen can be used in prostate cancer patients for screening and monitoring advanced disease. Cancer antigen 125 is primarily used for the monitoring of combined chemotherapy in ovarian cancer patients. In breast cancer patients preoperative levels of cancer antigen 15-3, carcinoembryonic antigen, and tissue polypeptide antigen specific do not contribute in prognosis, but changes in the levels of these markers predict the clinical outcome in the treatment of advanced disease better than UICC criteria. Carcinoembryonic antigen and tissue polypeptide antigen specific can detect recurrence in colorectal cancer patients earlier than imaging methods. Tissue polypeptide antigen specific is sensitive in measuring response to combined chemotherapy in advanced gastrointestinal cancer. In bladder cancer, urine levels of cytokeratins are sensitive in indicating advanced disease. In small-cell lung cancer neuron-specific enolase is a good indicator of chemotherapy response. In non-small-cell lung cancers, cytokeratins may also predict response in chemotherapy treatment. Clinical application of tumor markers in the correct circumstances can omit more invasive and costly procedures and will contribute to better patient care.

Validation of the determination of amino acids in plasma by high-performance liquid chromatography using automated pre-column derivatization with o-phthaldialdehyde

A sensitive and reproducible fully automated method for the determination of amino acids in plasma based on reversed-phase high-performance liquid chromatography and o-phthaldialdehyde pre-column derivatization is described. A 5-microns Spherisorb ODS 2 column (125 x 3 mm I.D.) was selected for routine determination. Over 40 physiological amino acids could be determined within 49 min (injection to injection) and 48 samples could be processed unattended. The coefficients of variation for most amino acids in plasma were below 4%. We were also able to measure trace amounts of amino acids in plasma normally not detected in a routine analysis. The results obtained with the method described compared favourably with those of conventional amino acid analysis (r = 0.997) and were in excellent agreement with those of other laboratories (r = 0.999).

Analytical requirements and standardization of CA 15-3

The CA 15-3 assay could play, probably in combination with cytokeratin markers, a role in the detection of early recurrence and in monitoring therapy in metastatic breast cancer patients. The CA 15-3 assay is, however, not useful for early detection of breast cancer and has no prognostic significance. The analyte is not clearly defined and a primary reference material cannot be synthesized. A reference measurement procedure is not available and many commercial assays use the original Centocor IRMA as such. The comparability of different CA 15-3 assays is not sufficient according to the results of EQAS. The general recommendations of analytical requirements for tumour marker determinations specified by the working group "Quality Control and Standardization" (Hamburger Symposia on Tumour Markers) includes intra-assay and inter-assay precision, drift, carry-over, dilution effect and high-dose hook effect. From a medical point of view reference limits should be established. Specificity/sensitivity profiles should preferentially be represented by ROCcurves. Confounding factors should be analyzed. To improve the clinical value of CA 15-3, the following needs for improvement have been identified: > Standardization of response criteria during treatment; > Definition of significant increase at recurrence; > Investigation of the biological variance during follow-up; > Definition of the analyte; > Preparation of reference material; > Development of an accepted reference method; > Integration of different international activities and > Optimizing decision-making criteria and clinical application.

Monoclonal antibody M3 used in tissue polypeptide-specific antigen assay for the quantification of tissue polypeptide antigen recognizes keratin 18

Recently, a new 'specific tissue polypeptide antigen (TPA)' test was introduced and designated tissue polypeptide-specific antigen (TPS); it is based on the monoclonal antibody (MAb) anti-TPS, M3. We have tested the specificity of this antibody by immunocyto- and immunohistochemistry, gel electrophoresis and immunoblotting. MAb M3 bound to intermediate filaments of epithelial cells and revealed a staining pattern identical to cytokeratin (CK) 18-specific MAb (DE-K18) on tissue sections of various human tissues. On immunoblots of proteins extracted from various epithelial cell lines, M3 reacted with a 45-kD protein corresponding to CK18, and on immunoblots of proteins isolated from MCF-7 culture fluid M3 stained three bands, 45, 33 and 29 kD. The same bands were stained with CK18-specific MAb, indicating that they represent CK18 and its degradation products. TPA, used as a tumor marker in clinical diagnoses and follow-up, was shown to be a degradation product of CK 8, 18 and 19. In contrast to TPA, MAb M3 did not stain CK8 and CK19 present on immunoblots.