The amino-terminal propeptide (PINP) of type I collagen is a clinically valid indicator of bone turnover and extent of metastatic spread in osseous metastatic breast cancer.

BACKGROUND: The efficacy control for the treatment of bone metastases in breast cancer is difficult and usually initiated later and with longer time between treatment cycles than the restaging of visceral or soft tissue metastases. The amino-terminal propeptide (PINP) of type I collagen as a biochemical indicator of bone turnover might facilitate early and valid disease surveillance. The utility of total PINP was investigated in metastatic breast cancer patients, with or without bone metastases (for monitoring of therapy). The results were compared to the established markers, osteocalcin and beta-carboxyterminal telopeptide (CTX) or crosslaps concentration. PATIENTS AND METHODS: Baseline serum samples of 51 patients with metastastic breast cancer under chemotherapy were investigated. In total, 38 patients had been diagnosed with bone metastases while 13 had no evidence of metastastic spread to the bone. All the patients with bone spread received bisphosphonates in addition to systemic chemotherapy and/or antibody therapy or hormonal treatment. Osteocalcin, CTX and PINP levels were measured on an Elecsys 2010 analyzer (electrochemiluminescence immunoassay--ECLIA). The normal cut-off values were: osteocalcin < 41.3 pg/ml, CTX < 1008 pg/ml and PINP < 95 ng/ml. Based on overall treatment outcome, the patients were grouped as responders (CR/PR), with stable disease (SD) or displaying primary progression (PD). RESULTS: The baseline levels of PINP were significantly higher in patients with bone metastases (median: 92.8 ng/ml) than in those without (median: 63.2 ng/ml, p = 0.044). Patients with more than seven bone metastases had significantly higher PINP levels (median: 149.7 ng/ml) than those with fewer than seven (median: 67.6 ng/ml, p = 0.04). Significant differences were also found for osteocalcin and CTX, at p = 0.02 and p = 0.04, respectively, although the median levels remained under the normal cut-off levels. In terms of response assessment of bone spread, the PINP concentrations decreased in responders from 194.3 ng/ml to 100.4 ng/ml (p = 0.23). In patients with SD, PINP remained at the same level of approximately 70 ng/ml (p = 0.16), but increased in patients with PD from 83.4 ng/ml to 176.5 ng/ml (p = 0.14). These trends rather than statistical difference were probably due to the limited patient cohort. No differences were found for the serum concentrations of PINP, CTX and osteocalcin between post- and pre-menopausal women. CONCLUSION: The PINP levels of the osseous metastatic breast cancer patients were elevated at baseline in comparison to those without bone involvement; the levels correlated to the number of bone metastases but were independent of the menopausal status. Thus, the levels of PINP under therapy might correlate with the response to therapy. Osteocalcin and CTX did not show similar sensitivity for the surveillance of bone metastases.

PINP as serum marker of metastatic spread to the bone in breast cancer patients.

BACKGROUND: Early detection before scintigraphic appearance of osseous metastatic spread might improve the outcome of breast cancer patients. The amino-terminal propeptide (PINP) of type I collagen as an indicator of bone formation is a very promising candidate among all markers of bone metabolism. We investigated the utility of total PINP in breast cancer patients at different stages of the disease. PATIENTS AND METHODS: Precision tests using controls and serum pools were done for total PINP on the Elecsys2010 analyzer (electrochemiluminescence immunoassay - ECLLA). Baseline samples of 51 breast cancer patients with metastatic disease plus 11 patients under neoadjuvant treatment were available. Altogether, 38 patients had been diagnosed with bone metastases while 24 had no evidence of metastatic spread to the bone. RESULTS: For serial precision (intra assay), we found coefficients of variation between 1.2-2%. Total imprecision according to the NCCLS protocol ranged from 1. 7-5.4% only. Retrieval in ring trials was between 94% and 103%. ROC analysis of osseous versus nonosseous metastatic disease revealed an area under the curve (AUC) of 0.72. The sensitivity for the detection of bone lesions was 50% at the preliminary normal cut-off of 95 ng/mL. The baseline levels of the patients with bone metastases were significantly higher than those of patients with visceral of soft tissue spread only (p<0.001). PINP concentrations correlated with osseous spread in terms of number and size of the bone lesions. Generally, non-osseous metastases did not produce elevated PINP levels in only 2/24 patients without bone metastases showing minimally elevated PINP concentrations (95 and 112 ng/ml). CONCLUSION: The Elecsys test for total PINP is highly reproducible. PINP concentrations can discriminate patients with bone metastases from those without osseous spread. The moderate sensitivity for the diagnosis of bone lesions may be biologically related to ineffective bone repair in a certain subset of patients. Further studies must focus on the monitoring of patients with elevated baseline levels and on those patients with low PINP levels in the case of otherwise proven bone metastases.

Discordant results obtained for different methods of HER-2/neu testing in breast cancer--a question of standardization, automation and timing.

BACKGROUND: HER-2/neu positivity is required for the selection of stage IV breast cancer patients for trastuzumab therapy. We compared the results of the recommended immunohistochemistry (IHC) evaluation with the automated ACIS IHC system and with fluorescence in situ hybridization (FISH). These HER-2/neu tissue results were correlated with the serum HER-2/neu (sHER-2/neu) levels at the time of metastatic spread. PATIENTS AND METHODS: A total of 61 IHC slides from 30 patients were stained using the HercepTest. HER-2/neu gene amplification was determined using the Ventana FISH assay. sHER-2/neu levels were measured with the Oncogene Science" ELISA kit. The concordance of HER-2/neu results was determined using the concordance index Kappa (kappa). RESULTS: The best concordance between any IHC and FISH was found for the automated ACIS system (88.5%, kappa=0.68, category "good"). The comparison between the manual interpretations and the automated IHC was categorized as "very good" (95.1%, kappa=0.85). The median sHER-2/neu level of FISH positive patients was significantly higher (67 ng/mL) than that of FISH negative patients (17 ng/mL, p=0.018). The increase in HER-2/neu positivity comparing tissue to stage IV serum was statistically significant (p=0.001). CONCLUSIONS: The concordance between conventional IHC and computerized analysis was very good. The number of patients with stage IV breast cancer with an elevated sHER-2/neu level was much higher than HER-2/neu positivity in tissue. This discrepancy is only partially explained by the influence of tumor load. Patients with an elevated sHER-2/neu level and no tissue overexpression should be considered for retesting of tissue or a new biopsy.

Upregulation of HER-2/neu by ovarian ablation: results of a randomized trial comparing leuprorelin to CMF as adjuvant therapy in node-positive breast cancer patients.

PURPOSE: HER-2/neu oncogene expression is modulated by an estrogen-sensitive binding site in the HER-2/neu promoter. Utilizing the circulating antigen of HER-2/neu in serum (sHER-2/neu) as a surrogate marker we investigated whether ovarian ablation by adjuvant therapy leads to an upregulation of HER-2/neu in breast cancer patients. PATIENTS AND METHODS: The analysis was done on sera from premenopausal, node-positive, hormone-receptor positive patients randomized in a multi-center trial. The study was designed with patients receiving either 11.25 mg of leuprorelin s.c. every 3 months over 2 years or CMF chemotherapy for 6 cycles. Sera, available from 80 patients in the leuprorelin arm and from 53 patients in the CMF arm, were collected at 0, 3, 6, 12, 18, 24 and 30 months. sHER-2/neu was measured using a standardized ELISA assay that has an upper limit of normal of 15 ng/ml. sHER-2/neu results were correlated to the levels of LH, FSH and estradiol as indicators of ovarian ablation and to the tumor marker, CA 27.29. RESULTS: During estradiol deprivation, sHER-2/neu levels increased significantly by more than one third from 8.1 ng/ml to 11.0 ng/ml (p < 0.0001) in both treatment arms. The most pronounced relative increase occurred within the first 3 months (p < 0.001). In only 2.7% (16/587) of sHER-2/neu measurements, the sHER-2/neu results were elevated above 15 ng/ml, confirming the upper limit of normal for breast cancer patients irrespective of their menopausal status. At month 30, the sHER-2/neu level started to decrease in the leuprorelin arm, reflecting reversible castration and estradiol reconstitution. Conversely, CA 27.29 levels did not show a trend over time, indicating that sHER-2/neu changes were of a regulatory nature and were not merely a reflection of increasing residual disease. CONCLUSION: Our study demonstrates the upregulation of HER-2/neu during ovarian ablation. These results are consistent with data showing that the percentage of HER-2/neu positive tumors, evaluated by standardized immunohistochemistry on the primary tumor, is significantly increased during the follicular phase of the menstrual cycle (Balsari et al., Am J Pathol 155: 1543-1547, 1999). Regulatory processes at the HER-2/neu gene should be considered when prescribing specific therapy for breast cancer.

Plasma levels of HER-2/neu, tumor type M2 pyruvate kinase and its tyrosine-phosphorylated metabolite in advanced breast cancer.

INTRODUCTION: Tyrosine kinase signal transduction pathways are a focus of interest for therapeutic interventions. The oncoprotein HER-2/neu shows tyrosine kinase activity leading to phosphorylation and activation of numerous second-messenger systems. One target of phosphorylation processes is assumed to be the tumor type M2 isoenzyme of pyruvate kinase (TuM2-PK) which has been shown to be elevated in metastatic breast cancer. MATERIALS AND METHODS: We measured the plasma levels of HER-2/neu, TuM2-PK and tyrosine-phosphorylated TuM2-PK (p-TuM2-PK) in 69 patients (pts) with breast cancer and correlated these parameters to each other and to the classical tumor marker CA 27.29. The samples were measured with ELISA assays while CA 27.29 was determined with an automated chemiluminescence assay. For analysis, we formed 5 subgroups according to the plasma HER-2/neu levels (group 1: < 15 ng/ml, n = 28; group 2: 15 < or = x < 50 ng/ml, n = 21; group 3: 50 < or = x < 100 ng/ml, n = 9; group 4: 100 < or = x < 500 ng/ml, n = 7; group 5: > or = 500 ng/ml, n = 4). RESULTS: From the HER-2/neu group 1 to group 5, there was a statistically significant increase of CA 27.29 from 35.8 U/ml to 1095.8 U/ml (p < 0.001). There was also a trend for increasing TuM2-PK levels with increasing HER-2/neu levels (p = 0.126). From the lowest extinction (0.088) to the highest extinction result (2.167) of p-TuM2-PK we found a 25-fold increase, which was reproducible in spiking and dilution experiments proving that TuM2-PK is phosphorylated at tyrosine residues to a certain extent. However, there was no correlation between plasma HER-2/neu and p-TuM2-PK levels. CONCLUSION: TuM2-PK is phosphorylated at tyrosine residues in breast cancer patients. Using the shed antigen of HER-2/neu in plasma as a surrogate marker, we did not find any evidence that this phosphorylation is initiated by the oncoprotein HER-2/neu.

Normalisation of biochemical markers of bone formation correlates with clinical benefit from therapy in metastatic breast cancer.

BACKGROUND: Type I collagen is the most abundant protein of bone. We measured a panel of biochemical markers of bone metabolism including the amino-terminal propeptide (PINP) of type I collagen, the carboxy-terminal telopeptide (ICTP) of type I collagen, the urinary desoxypyridinium (DPD) crosslinks excretion, the alkaline phosphatase (AP) and serum calcium (Ca) levels as well as CA 27.29 as mass tumor marker in 73 breast cancer patients with bone metastases under specific antitumor therapy and supportive treatment with pamidronate. PATIENTS AND METHODS: Representative longitudinal single-time-point evaluations of all markers were correlated to response assessment in UICC criteria. Restaging was done by standard procedures. PINP and ICTP were measured using standardized radioimmunoassays with cut-offs of normal of 84 micrograms/l and 5 micrograms/l, respectively. DPD was measured on a chemiluminescence basis using an upper limit of normal of 13 nmol/mmol. RESULTS: The distributions of all pooled levels of CA 27.29 and AP were statistically significantly different (or just missed statistical significance) between patients with stabilized disease as compared to progressing patients with p = 0.012 for CA 27.29 and p = 0.053 for AP. AP was the only parameter which normalized below the cut-off of normal statistically significantly (p = 0.003) more often in the group of patients with clinical benefit as compared to progressive patients. PINP showed the second best result for normalisation with p = 0.083, though missing statistical significance. CONCLUSION: Clinical benefit from systemic therapy was primarily accompanied by a normalization of biochemical markers representing bone formation. This result reflects the physiology of the "bone remodeling unit". In patients without this normalization, thorough and early restaging is warranted since the systemic therapy may be ineffective.

Biomarkers and imaging in non-malignant and malignant osteomalacia.

Deoxypyridinium (DPD) cross-links are a specific parameter for collagen type I degradation. We report the longitudinal tracking of DPD in relation to other bone markers and imaging techniques in a patient with osteomalacia and secondary hyperparathyroidism from reduced light exposure due to attire. This patient was first admitted for diffuse skeletal pain. X-rays showed general demineralization and Looser's transformation zones in the neck of the left femur. MRI examinations of the pelvis and the proximal femora demonstrated bilateral signs of acute sacroiliitis, as well as edema-like lesions in the femoral heads and necks bilaterally. The baseline parathyroid hormone level was 8 times higher than the normal upper limit, whereas 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels were significantly reduced. A 7-fold increase in free urinary DPD and a 17-fold increase in bone-specific alkaline phosphatase (bone-AP) were also measured. Percutaneous transiliac bone biopsy revealed markedly increased osteoidosis. Osteomalacia was diagnosed due to chronically reduced sun exposure caused by restrictive attire, and cholecalciferol substitution therapy was begun. After a follow-up of 28 weeks, non-specific parameters of bone turnover (parathyroid hormone, total alkaline phosphatase, serum calcium and serum phosphate) had normalized, while DPD, as a specific bone degradation marker, and bone-AP, as a bone formation parameter, both remained elevated. This example underlines the validity of DPD and bone-AP as indicators of increased bone metabolism: not only were they the parameters with the highest baseline deviation, but they were also the last to normalize.

Tumor type M2 pyruvate kinase expression in advanced breast cancer.

BACKGROUND: Recently, a high validity correlation of the tumor M2 pyruvate kinase (Tu M2-PK) isoenzyme in comparison to standard tumor markers has been demonstrated in solid tumors. We investigated this marker in 67 patients with advanced breast cancer (ABC) in comparison to healthy controls. MATERIALS AND METHODS: Plasma Tu M2-PK was measured using an ELISA assay (ScheBo Tech, Giessen, Germany) while serum CA27.29 was determined using a chemiluminescent immunoassay (Bayer Diagnostics, Tarrytown, USA). RESULTS: In a ROC analysis, the cut-off to discriminate patients from controls was established at 15 U/ml for Tu M2-PK (specificity 85%; positive predictive value 81%) and 30 U/ml for CA27.29 (specificity 91%; positive predictive value 92%). Median ABC baseline levels (ranges) in patients with ABC for Tu M2-PK and CA27.29 were 12.8 U/ml (4.8-252,495) and 130 U/ml (13.3-8130), respectively. Response assessment was done in 45 chemotherapy courses of 38 pts. In 13 out of 19 blocks (68.4%) with PD (progressive disease), an elevated level of Tu M2-PK at baseline or in the follow-up was found. In 17 out of 20 blocks (85%) with SD (stable disease), the Tu M2-PK level was normal at baseline or normalised within 4 weeks of treatment. All 6 patients with disease remission had a normal baseline Tu M2-PK level or the levels decreased promptly. CONCLUSION: Tu M2-PK gives additional information about ABC, indicating disease activity and sensitivity to chemotherapy while CA27.29 reflects tumor burden.

A comparison of bone-related biomarkers and CA27.29 to assess response to treatment of osseous metastatic breast cancer.

BACKGROUND: The assessment of bone metastases by clinical examination or imaging techniques is still considered unreliable. We compared a specific marker of bone resorption, urinary deoxypyridinoline (DPD)-crosslinks, with serum calcium (Ca), alkaline phosphatase (AP) and CA27.29, to evaluate the status of bone metastases in patients with breast cancer. MATERIALS AND METHODS: Second morning voided urine was collected from 2 groups of patient (pts), those without evidence of disease (n = 118), and those with bone metastases (n = 85) under specific therapy plus pamidronate. DPD and CA27.29 were measured on the automated ACS180 system (Bayer Diagnostics, Tarrytown, NY, USA). Receiver operating characteristics (ROC) curves were established for each of the 4 biomarkers to determine whether they could distinguish the 2 subsets of pts with clinically sufficient validity, and to establish the corresponding cut-off values. RESULTS: Neither Ca nor AP was useful in discriminating the 2 subgroups. At a DPD cut-off of 13 nmol/mmol, we found a specificity of 69% and a sensitivity of 53% for diagnosing bone metastases. Best results, however, were seen for CA27.29. A cut-off value of 30 U/ml resulted in a specificity of 62% and a sensitivity of 81%. CONCLUSIONS: CA27.29 was the best parameter for the discrimination of stage IV breast cancer with bone metastases. The primary advantage of DPD lies in the monitoring of bone metastases under specific therapy.

[Congenitally corrected transposition of the great vessels in adulthood. The value of noninvasive study methods]. / Kongenital korrigierte Transposition der grossen Arterien im Erwachsenenalter. Wert nicht-invasiver Untersuchungsmethoden.

A 57-year-old man with a cough and increasing exertional dyspnoea for the past 6 weeks was found on examination to have a loud systolic murmur and cardiomegaly with pulmonary congestion. Echocardiography revealed congenitally corrected transposition of the great arteries (cTGA: atrioventricular and ventriculoarterial discordance): a morphologically right ventricle with a tricuspid valve on the left, a morphologically left ventricle with bicuspid a-v valve on the right, the aorta arising ventrally from the left-sided (morphologically right) ventricle. The tricuspid valve showed an Ebstein-like anomaly with obvious regurgitation. Transoesophageal and contrast echocardiography defined valvar anatomy, attachment of the great arteries and cardiac chambers to the venous and arterial circulations, as well as absence of a left to right shunt. Angiography revealed a coronary anatomy typical for cTGA. The exertional dyspnoea responded to diuretics and low doses of ACE inhibitor. Follow-up monitoring of the valvar regurgitation and appropriate endocarditis prophylaxis were recommended. As the haemodynamics in cTGA is normal, in the absence of additional anomalies, it is a congenital cardiac defect which can, though rarely, present first in adulthood. Life expectancy depends on the nature of any additional defects and the degree of commonly associated tricuspid valve regurgitation. As this case demonstrates, echocardiography can largely define the anomalies.