A Hospital Survey of Hypocalcemia and Hypophosphatemia in Malignancy

We evaluated the incidence of hypo- versus hypercalcemia and hypo- versus hyperphosphatemia in a survey of 158 patients with malignancy; 55/158 had bone metastases. When serum calcium levels were corrected for albuminemia, the incidence of hypo- and hypercalcemia was respectively 10.8% and 10.1 %. Hypophosphatemia was found in 29.7% patients, hyperphosphatemia in 2.5 %. The incidence was slightly different in presence of bone metastases. Hypocalcemia and hypophosphatemia prevailed In osteoblastic metastases and hypercalcemia in osteolytic metastases. The incidence of hypocalcemia and hypophosphatemia in malignancy was therefore surprisingly high, even apart from the presence of bone metastases. Both hypo- and hypercalcemia were associated with elevated serum alkaline phosphatase levels. Moreover, a calcium-phosphorus product reduction was observed in osteoblastic metastases, suggesting a condition of secondary hyperparathyroidism.

Accuracy and Clinical Correlates of Two Different Methods for Chromogranin A Assay in Neuroendocrine Tumors

Measurement of chromogranin A (CgA) plays a major role in the management of neuroendocrine tumors (NET); however, reliable assaying of CgA is made difficult by the rapid hydrolysis following its release into the bloodstream. This study was aimed at the assessment of two assays for CgA in NET patients. CgA was measured in 93 patients by means of an enzyme-linked immunosorbent assay (ELISA) and an immunoradiometric assay (IRMA). The specificity and sensitivity of CgA were evaluated in relation to tumor histology. The clinical accuracy of the two assays was evaluated by receiver-operating characteristic (ROC) curve analysis. Regression analysis demonstrated different immunoreactivity for CgA of the antibodies used in the two kits (r=0.61). The two assays had different accuracy also in classifying patients according to their clinical condition (91% vs 64% specificity and 79% vs 79% sensitivity for the ELISA and IRMA assay, respectively) and tumor histology (81% vs 85% sensitivity for the ELISA and IRMA assays, respectively, in carcinoids; 92% vs 67% sensitivity for the ELISA and IRMA assays, respectively, in pancreatic islet cell tumors). The different clinical accuracy of the two assays was confirmed by the ROC analysis (AUC=0.90 vs AUC=0.87 for the ELISA and IRMA assays, respectively). In conclusion, because of the poor standardization of the commercially available measurement tools the clinical accuracy of CgA measurement depends on the assay used. This makes it difficult to compare CgA values measured with different kits and affects the clinical accuracy of the different assays for CgA.

Radioembolization of hepatocarcinoma with (90)Y glass microspheres: development of an individualized treatment planning strategy based on dosimetry and radiobiology

PURPOSE

The aim of this study was to optimize the dosimetric approach and to review the absorbed doses delivered, taking into account radiobiology, in order to identify the optimal methodology for an individualized treatment planning strategy based on (99m)Tc-macroaggregated albumin (MAA) single photon emission computed tomography (SPECT) images.

METHODS

We performed retrospective dosimetry of the standard TheraSphere® treatment on 52 intermediate (n = 17) and advanced (i.e. portal vein thrombosis, n = 35) hepatocarcinoma patients with tumour burden < 50% and without obstruction of the main portal vein trunk. Response was monitored with the densitometric radiological criterion (European Association for the Study of the Liver) and treatment-related liver decompensation was defined ad hoc with a time cut-off of 6 months. Adverse events clearly attributable to disease progression or other causes were not attributed to treatment. Voxel dosimetry was performed with the local deposition method on (99m)Tc-MAA SPECT images. The reconstruction protocol was optimized. Concordance of (99m)Tc-MAA and (90)Y bremsstrahlung microsphere biodistributions was studied in 35 sequential patients. Two segmentation methods were used, based on SPECT alone (home-made code) or on coregistered SPECT/CT images (IMALYTICS™ by Philips). STRATOS™ absorbed dose calculation was validated for (90)Y with a single time point. Radiobiology was used introducing other dosimetric variables besides the mean absorbed dose D: equivalent uniform dose (EUD), biologically effective dose averaged over voxel values (BEDave) and equivalent uniform biologically effective dose (EUBED). Two sets of radiobiological parameters, the first derived from microsphere irradiation and the second from external beam radiotherapy (EBRT), were used. A total of 16 possible methodologies were compared. Tumour control probability (TCP) and normal tissue complication probability (NTCP) were derived. The area under the curve (AUC) of the receiver-operating characteristic (ROC) curve was used as a figure of merit to identify the methodology which gave the best separation in terms of dosimetry between responding and non-responding lesions and liver decompensated vs non-decompensated liver treatment.

RESULTS

MAA and (90)Y biodistributions were not different (71% of cases), different in 23% and uncertain in 6%. Response correlated with absorbed dose (Spearman's r from 0.48 to 0.69). Responding vs non-responding lesion absorbed doses were well separated, regardless of the methodology adopted (p = 0.0001, AUC from 0.75 to 0.87). EUBED gave significantly better separation with respect to mean dose (AUC = 0.87 vs 0.80, z = 2.07). Segmentation on SPECT gave better separation than on SPECT/CT. TCP(50%) was at 250 Gy for small lesion volumes (<10 cc) and higher than 1,000 Gy for large lesions (>10 cc). Apparent radiosensitivity values from TCP were around 0.003/Gy, a factor of 3-5 lower than in EBRT, as found by other authors. The dose-rate effect was negligible: a purely linear model can be applied. Toxicity incidence was significantly larger for Child B7 patients (89 vs 14%, p < 0.0001), who were therefore excluded from dose-toxicity analysis. Child A toxic vs non-toxic treatments were significantly separated in terms of dose averaged on whole non-tumoural parenchyma (including non-irradiated regions) with AUC from 0.73 to 0.94. TD50 was ≈ 100 Gy. No methodology was superior to parenchyma mean dose, which therefore can be used for planning, with a limit of TD15 ≈ 75 Gy.

CONCLUSION

A dosimetric treatment planning criterion for Child A patients without complete obstruction of the portal vein was developed.

Inflammation and immune response in acute aortic dissection

OBJECTIVE

The aim of our study was to evaluate the lymphocyte subpopulations and the cytokines in the peripheral blood of patients with type-A Stanford acute aortic dissection (AAD group) and to determine whether inflammatory cells are present at the site of aortic dissection.

METHODS

Thirty-five consecutive patients with type-A Stanford dissection were evaluated for haemochrome and lymphocyte subpopulations (CD3+, CD4+, CD8+, CD19+, CD4+CD25+, CD16+CD56+, CD4+CD28-, CD8+CD28-) by flow cytometry. C-reactive protein (CRP), tumour necrosis factor (TNF)-α, interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (IFN-γ), and monocyte chemoattractant protein (MCP)-1 were measured by ELISA. In addition, immunohistochemical staining with cell type-specific antibodies was performed to study the inflammatory cells detected inside the aortic wall.

RESULTS

In the AAD group, a significant increase in natural killer (NK) (P = 0.032), B cells (P = 0.022), and CD8+CD28- (P = 0.045) subpopulations was observed, whereas there was a significant decrease in total T lymphocytes (P = 0.004) and T helper fractions (P = 0.005). Moreover, a significant increase in CRP (P < 0.0001), IL-6 (P < 0.0001), IL-8 (P < 0.0001), IL-10 (P < 0.0001), TNF-α (P < 0.0001), and MCP-1 (P < 0.001) was observed; macrophages represented the main population detected inside the media.

CONCLUSIONS

Our results strongly support the hypothesis of a pivotal role of innate immunity in type-A Stanford AAD.

Transient osteoporosis of the hip

Transient osteoporosis of the hip (TOH) is not an uncommon condition, usually with a benign course. The syndrome classically affects women during the last trimester of pregnancy, but also middle aged men. Recently, TOH has been described in non pregnant women. The pathophysiology of the disease is uncertain, though several hypotheses have been suggested. Joint pain is the main symptom. TOH is a self-limited condition, which resolves spontaneously with complete recovery within several months in most cases.

A new predictive index for vertebral fractures: the sum of the anterior vertebral body heights

Evaluation of osteoporotic vertebral fracture risk is currently based on measurement of bone mineral density (BMD), but bone strength depends also on bone quality parameters. Aim of this study was to evaluate the validity of a new vertebral morphometric index, the Anterior Vertebral Heights sum (AHs) in discriminating women at high risk of vertebral fracture, comparing its diagnostic accuracy with that of BMD measured at lumbar spine (LS-BMD) and femoral neck (FN-BMD).

MATERIALS AND METHODS

A total of 163 Caucasian post-menopausal women (age range 46-74 years, mean age+/-SD=63.8+/-7.1 years), who did not present prevalent fractures at baseline evaluation, were observed at longitudinal follow-up. X-ray of the thoracic and lumbar spine, LS-BMD and FN-BMD measurements were obtained in all patients at baseline and repeated at the second follow-up visit 18-24 months later (mean 21+/-1.7 months). Radiographs of spine were analysed in order to identify vertebral fractures using a visual semiquantitative method (SQ) and vertebral morphometry as well as by calculating the AHs morphometric index.

RESULTS

During follow-up, 21/163 patients (12.9%) sustained a new vertebral fracture; 95.2% (20/21) of fractured patients but only 4.9% (7/142) of non-fractured women had reduced AHs values. As regarding BMD, 66.6% (14/21) and 61.9% (13/21) of women with incident fracture were osteoporotic at lumbar spine and femoral neck baseline evaluation , whereas among non-fractured women, 38% (54/142) at LS-BMD and 33.1% (47/142) at FN-BMD were osteoporotic . Analyses of Receiver Operating Characteristic (ROC) curves showed that AHs discriminated vertebral fractures almost perfectly (AUC 0.97; 95% CI 0.95-0.99). On the other hand, the AUC for LS-BMD was only 0.73 (95% CI 0.64-0.81) and for FN-BMD was 0.72 (95%CI 0.63-0.80), showing that the diagnostic accuracy of AHs was significantly higher compared to that of LS-BMD (p<0.001) or FN-BMD (p<0.001). A modified Poisson regression model for binary data was used to assess the independent role of AHs in predicting vertebral fracture. The effect of AHs remained statistically significant (p<0.001) after adjusting by FN-BMD, age, weight and body height.

CONCLUSIONS

Results of this study indicate the validity of this new morphometric index in evaluating the risk of osteoporotic vertebral fractures thus suggesting that AHs should be considered a valid parameter in clinical practice to assess the need for primary prevention of vertebral fractures.

Treatment with tandem [(90)Y]DOTA-TATE and [(177)Lu] DOTA-TATE of neuroendocrine tumors refractory to conventional therapy: preliminary results

AIM

Neuroendocrine tumors over-express somatostatin receptors and literature data have demonstrated the efficacy of the peptide receptor radionuclide therapy with somatostatin analogues labelled with high activities of b-emitting radioisotopes, such as (90)Y and (177)Lu. Yttrium-90 is a pure high energy b-emitter while (177)Lu is a b/g emitter of medium energy. We decided to evaluate an original tandem treatment based on administration of radiolabeled [DOTA(0),Tyr(3)]octreotate (DOTA-TATE) alternating (177)Lu and 90Y. Aim of this study was to evaluate the feasibility, the efficacy and the toxicity of this treatment in neuroendocrine tumors expressing somatostatin receptors relapsed or refractory to conventional therapies.

METHODS

Patients were treated with four therapeutic cycles alternating [(177)Lu]DOTA-TATE (5.55 GBq) and [(90)Y]DOTA-TATE (2.6 GBq). Dosimetric evaluation after administration of [(177)Lu]DOTA-TATE allows to calculate the absorbed doses in healthy organs. Blood samples were collected at 5 min, 1, 6, 24, 48, 72, 96 h and scintigraphy was performed once a day for four days after administration. Toxicity was evaluated considering hematological parameters and renal toxicity was evaluated also by the glomerular filtration rate (GFR). Efficacy related with RECIST criteria.

RESULTS

Up to now 26 patients entered the study and 16 patients completed all cycles. Treatment was well tolerated with no adverse event registered. No damage to healthy organs was revealed in accordance with the calculated absorbed doses. We had a partial response in 10/15 patients evaluated three months after the fourth treatment.

CONCLUSIONS

Up to now only a few patients participated in and concluded this study; preliminary results are encouraging and indicate the feasibility of the study.

Platelet and hemocoagulative changes in elderly atherosclerotic patients after treatment with the antiaggregating drug picotamide

The effects of the antiaggregating drug picotamide on platelet and hemocoagulative parameters were evaluated in a group of 28 elderly atherosclerotic patients. After 1 month of treatment, consisting of one 300 mg tablet three times per day, a significant inhibition of platelet aggregability in response to ADP, adrenaline, arachidonic acid and collagen and a reduction of the mean platelet volume (-4.62+/-7.46%, P<0.003) was observed. Fibrinogen plasma levels, unchanged at the 15th day, were significantly reduced at the 30th day, from 445.6+/-145.95 to 382.72+/-110.56 mg/dl (P<0.01), while no changes were observed in antithrombin III, factor VII, D-dimer plasma levels and in plasmatic and urinary fibrin(ogen) degradation products values. The results seem to indicate a reduction after antiaggregating treatment of the interaction between the platelets and the vessel wall, that may be responsible for the changes observed.

Male osteoporosis

Osteoporosis is a worldwide major public health problem, defined as "a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fractures". Osteoporosis is diagnosed by bone mineral density measurement (T-score of -2.5 or below) also in men. However, most of the studies carried out in the last decade focused on pathogenesis, diagnosis and treatment of osteoporosis in women. In spite of this, recent epidemiological and observational studies have shown that osteoporosis in men is an increasingly important clinical issue. In part because the world population is aging, it is likely that the total number of hip fractures in men in 2025 will be similar to current estimates in women. Furthermore 25-33% of men in some populations will sustain osteoporotic fractures in their lifetime. Nevertheless, male osteoporosis is still underdiagnosed and further studies are required to clarify the pathogenesis and find out the right therapy. Prevention and early diagnosis are, nowadays, the best ways of treatment.

A practical dead time correction method in planar activity quantification for dosimetry during radionuclide therapy

AIM

Gamma camera saturation is the first quantification problem in dosimetric studies following therapeutic administrations of 131I labeled radiopharmaceuticals. A new approach for dead time correction (DTC) is here proposed. It employs planar whole-body (WB) images without the need of standard radionuclide sources or of preliminary phantom calibrations.

METHODS

Step and shoot WB acquisitions of the patient are required. A program was developed to compensate for the image discontinuities ("Continuity DTC method") between two adjacent static fields of view (FOVs) caused by different dead time count losses. For its validation, authors used two 99mTc 6 GBq phantom scans after administration of six patients with 131I labeled agents with different statistics and ten clinical scans taken between 16 h and 48 h after administration of 131I labeled agents, whose activity ranged from 4 to 10 GBq. The deviation from true decay corrected counts on phantoms and the constancy of monitor point-source counts in different patients' FOVs (root mean square error and maximum deviation) served as figures of merit. The accuracy of absorbed dose calculation was also estimated by comparison with the standard source correction method, computing the area under the time activity curve (AUC) of six lesions.

RESULTS

With respect to the true phantom counts, corrected images gave excellent results, giving a 6% maximum deviation. For what concerns the other figures of merit, continuity DTC reduced the average root mean square error from 36% to 2% and the mean maximum deviation from 50% to 2%, on phantom, while from 51% to 32/28% (absence/presence of triple energy window scatter correction) and from 72% to 21/14% on patients. Mean compensation of AUC gave a correction of +56% with our method, while +78% with standard source method.

CONCLUSIONS

The "Continuity DTC method" is a useful tool in dosimetry during nuclear medicine treatment, showing good accuracy. Moreover, since it does not require the use of any source, it provides with several advantages in terms of practicability and applicability, with respect to the standard source method and to methods based on the count rate characteristic curve.

Individualized dosimetry in the management of metastatic differentiated thyroid cancer

AIM

This paper analyzes the available data on the dosimetric approach and describes the use of dosimetry in the Division of Nuclear Medicine of the National Cancer Institute in Milan. Dosimetry is rarely performed when planning radio-iodine activity, although most of the available guidelines do mention this possibility, without giving any well defined indication. Aim of the present research was to validate the usefulness of dosimetry in the management of metastatic thyroid cancer. Benua (1962) set the limit of blood absorbed dose at 2 Gy to avoid hematological toxicity. Maxon (1983) determined at 80 Gy the dose to achieve complete destruction of a metastatic lesion. Dorn (2003) combined red marrow and lesion dosimetry showing that high activity administrations with less that 3 Gy to the red marrow are a safe and more effective with respect to fixed activities administrations. Lee (2008) reported 50% responses with high activity administrations based on blood dosimetry, in 47 patients which were unsuccessfully previously treated with fixed activities. Sgouros (2005) and Song (2006) introduced key parameters as Biological Effective Dose and Uniform Equivalent Dose in order to describe the effects of continuous low dose rate irradiation and non uniform activity uptake, typical of nuclear medicine treatments.

METHODS

Red marrow and lesion dosimetry (planar view) were performed during the treatment, without changing the fixed activity schema.

RESULTS

This experience demonstrate first of all, that dosimetry is feasible in the clinical routine, and that it can provide the clinician with important information, no matter its often quoted limited numerical accuracy. A total of 17/20 lesion doses below 80 Gy have been detected. Three/17 (doses between 40 and 80 Gy) disappeared in the follow-up scintigram. Two/17 were undetectable at computed tomography or nuclear magnetic resonance. These data suggest that repetition of treatment on a lesion drastically reduces its uptake, with a loss of therapeutic efficacy along the sequence of fixed activity administrations.

CONCLUSIONS

The usefulness of dosimetry should not be assessed only on the basis of patient survival or therapeutic efficacy; the possibility to avoid useless treatments should also be considered. According to the authors, individualized dosimetry could improve the management of metastatic differentiated thyroid cancer. Even post-therapeutic dosimetry, as performed at this institution, has a significant impact on clinical decision-making. The question for the future is how to include dosimetry into the patient management framework.

[The plasma fibrinogen as a marker of subclinical carotid atherosclerosis]

The aim of this study is to evaluate if plasma fibrinogen levels could correlate with carotid lesions.

METHODS

We investigated the plasmatic levels of fibrinogen in 100 patients with asymptomatic carotid lesions, examined at ultrasound, and with at least one traditional cardiovascular risk factor.

RESULTS

We found a significant correlation between plasma fibrinogen levels and severity of carotid lesions: intima-media thickness (p < 0.001), stenosis <70% (p < 0.002), stenosis 270% (p < 0.001).

CONCLUSIONS

Beyond traditional cardiovascular risk factors, high plasmatic levels of fibrinogen significantly correlate with the thickness of carotid wall in asymptomatic subjects.

Renal Limited Wegener’s granulomatosis

Differential diagnosis in patients presenting with fever of unknown origin (FUO) is often difficult because infectious diseases, neoplasms, infective endocarditis or systemic autoimmune diseases may all be responsible for the condition. Furthermore, vasculitis may generate typical, atypical or limited syndromes depending on the extent of vascular involvement. Here, we report the case of a 73-year-old man with FUO and renal failure due to a rare variant of Wegener’s granulomatosis, limited to the kidneys.

[Neurofibromatosis type I and hypertension: a case report]

Pheochromocytomas are catecholamine-producing neuroendocrine tumors arising from chromaffine cells derived from the embryonic neural crest. They occur in 0.1-5.7% of patients with neurofibromatosis type 1 (von Recklinghausen's disease). We report the case of an adrenal pheochromocytoma in a patient with neurofibromatosis type 1.

MIBG for diagnosis and therapy of medullary thyroid carcinoma: is there still a role?

Medullary thyroid carcinoma (MTC) is a relatively rare neuroendocrine tumour originating from the parafollicular C cells and releases calcitonin (hCt), carcinoembryonic antigen (CEA) and occasionally other substances. In 20-30% of cases MTC presents a germline mutation of the RET proto-oncogene and occurs in 3 different hereditary forms: familial MTC, multiple endocrine neoplasia (MEN) 2A and MEN 2B syndrome. Prognosis of MTC is largely related to tumour extension at disease onset. Surgery remains the most effective therapy for potential cure. Overall survival is strictly linked to the occurrence of relapse. After surgery, serum hCt remains the most sensitive test for occult disease. Diagnostic imaging work-up includes ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), bone scintigraphy, as the more frequent sites of recurrence or metastases are cervical and mediastinal lymph nodes, lungs, liver and bone. Nuclear medicine procedures include (111)In-labelled somatostatin analogs, radioiodinated metaiodobenzylguanidine (MIBG), and several PET radiopharmaceuticals. Experience with radionuclide therapy in MTC is restricted to few patients treated with (131)I-MIBG or (90)Y-DOTATOC. Since 1987, 1 027 diagnostic MIBG scans were performed in the Department Department of Diagnostic Imaging and Therapy of the Istituto Nazionale Tumori IRCCS Foundation (Milan, Italy), 85 of which for MTC, with a sensitivity of 38.7% in patients with evidence of disease and 30.7 % if all patients were considered. Since 1994, 13 MTC patients were treated with MIBG with 4 partial responses and 4 stable diseases. Patients with liver or bone involvement responded to therapy and showed long-term partial remission of disease, others showed stability of disease, which was apparently unrelated to therapy. Improvement of efficacy can be achieved through dosimetric calculation of administered activity.

[Splenic infarction after warfarin discontinuation during atrial fibrillation]

We describe a case of patient with splenic infarction, admitted to our department for sudden abdominal pain and fever after discontinuation of anticoagulant therapy for atrial fibrillation, complicating a dilated myocardiopathy and mechanical prosthetic valve. Diagnosis of splenic infarction was made by enhanced-contrast computed tomography, while ultrasounds and radiography were negative. Anticoagulant therapy, gold-standard treatment, was followed by fast clinical improvement. Moreover, splenic infarction should be considered in all cases of acute or chronic pain in left hypochondrium and especially in patients with emboligenous cardiopathies or atrial fibrillation, the most common arrhythmia source of peripheral embolism in clinical practice.

Antithrombin III metabolism in the pulmonary vessel endothelium

In 85 patients undergoing aorto-coronary bypass for atherosclerotic coronary disease, we measured the antithrombin III activity levels and the thrombin-antithrombin III complex concentrations in blood from the pulmonary and the radial arteries, taken before the aorto-coronary bypass procedure, with the aim of investigating the role of the pulmonary endothelium in the metabolism of the inhibitor. Results showed significantly lower mean antithrombin III activity levels, expressed as a percentage of normal plasma, in blood from the radial artery with respect to levels from the pulmonary artery (0.78 +/- 0.12 versus 0.80 +/- 0.12, P<0.0001), while no significant difference was found in thrombin-antithrombin III complex concentrations. The results seem to show that the pulmonary endothelium contributes to the antithrombin III metabolism with a 0.023 breakdown rate, corresponding to about a 0.1 fraction of the reported 0.22-0.25 total body catabolic rate, as well as the pulmonary endothelial surface (50-70 m2) corresponding to about a 0.1 fraction of the peripheral vessels' endothelial surface (500-700 m2). The data support the hypothesis of a main endothelial catabolism of antithrombin III.

Bisphosphonate treatment in ochronotic osteoporotic patients

In ochronotic patients, abnormalities in bone metabolism leading to increased bone loss have been reported. Therefore, we attempted antiresorptive therapy to (almost) partially reverse bone loss in four out of five osteopenic or osteoporotic ochronotic patients, two men and two women, aged 56-82 years. Each patient was treated with a 70-mg tablet of alendronate weekly and 1,000 mg/day of elemental calcium, such as gluconolactate or carbonate, throughout 24 months. Before starting therapy, and after 1 and 2 years of treatment, the bone mineral density (BMD) at the femoral subregions and at the lumbar spine was measured (in grams per square centimeter and as a T score) by dual energy X-ray absorptiometry. A 50-year-old osteopenic ochronotic man refusing the treatment underwent the same checks. The BMD was measured in all patients on the same densitometer by the same operator. The results showed a progressive decrease of the femoral subregion BMD measurements both in the bisphosphonate-treated patients and in the untreated patient. In particular, the percentage differences with respect to the basal values of the total femur BMD measurements ranged from -0.52 to -6.72% in the first year and from -5.29 to -9.05% in the second year. The lumbar spine BMD measurements provided spuriously overestimated results. Moreover, two treated patients and the untreated patient experienced fragility fractures of the femur. The study showed that osteoporosis and fragility fractures are prominent manifestations in the natural history of ochronosis. Matrix microdamage, osteocyte viability, and collagen cross-linking impairment, due to homogentisic acid and to its polymer, might be the processes involved. For this reason, the bisphosphonate therapy was ineffective.

Lymphoscintigraphy with intraoperative gamma probe sentinel node detection: clinical impact in patients with head and neck melanomas

AIM

The aims of this paper were to evaluate the clinical relevance of lymphoscintigraphy with intraoperative gamma-probe detection in identifying sentinel nodes (SNs) and to study the prognostic value of SN biopsy in head and neck melanoma patients.

METHODS

Sixty-one patients had lymphoscintigraphy with intradermal injections of 99mTc-Nanocoll (40 MBq), 24 h before surgery. Tumor-positive SNs patients underwent total lymph node dissection. Postoperative histological examination was performed. Patients were followed up for 1 to 5 years (median 3 years). The tumor relapses and the overall survival were evaluated by means of statistical methods.

RESULTS

Lymphoscintigraphy showed lymphatic distribution to more than one basin in 45 patients (74%), in 15 patients one basin was visualized and no basin in 1 patient. In 41 patients the SN was negative for metastases, while in 20 was positive. In a high percentage of patients (30%), metastatic involvement occurred in more than one lymph node basin. During follow-up in the negative SN group, 40 patients remained disease free and 1 relapsed. In the positive SN group, 10 patients remained disease free and 10 relapsed. Recurrence time ranged from 6 to 11 months. The overall survival of the SNs negative group was significantly higher than the positive SN group.

CONCLUSIONS

This approach was able to distinguish: a) patients with tumor-negative SNs with a favorable clinical course (98% did not relapse, P<0.001); b) patients with tumor-positive SNs with a high rate of tumor relapse (50%, P<0.001). Therefore SN biopsy may give information about prognosis in head and neck melanoma patients.

Accuracy and clinical correlates of two different methods for chromogranin A assay in neuroendocrine tumors

Measurement of chromogranin A (CgA) plays a major role in the management of neuroendocrine tumors (NET); however, reliable assaying of CgA is made difficult by the rapid hydrolysis following its release into the bloodstream. This study was aimed at the assessment of two assays for CgA in NET patients. CgA was measured in 93 patients by means of an enzyme-linked immunosorbent assay (ELISA) and an immunoradiometric assay (IRMA). The specificity and sensitivity of CgA were evaluated in relation to tumor histology. The clinical accuracy of the two assays was evaluated by receiver-operating characteristic (ROC) curve analysis. Regression analysis demonstrated different immunoreactivity for CgA of the antibodies used in the two kits (r = 0.61). The two assays had different accuracy also in classifying patients according to their clinical condition (91% vs 64% specificity and 79% vs 79% sensitivity for the ELISA and IRMA assay, respectively) and tumor histology (81% vs 85% sensitivity for the ELISA and IRMA assays, respectively, in carcinoids; 92% vs 67% sensitivity for the ELISA and IRMA assays, respectively, in pancreatic islet cell tumors). The different clinical accuracy of the two assays was confirmed by the ROC analysis (AUC = 0.90 vs AUC = 0.87 for the ELISA and IRMA assays, respectively). In conclusion, because of the poor standardization of the commercially available measurement tools the clinical accuracy of CgA measurement depends on the assay used. This makes it difficult to compare CgA values measured with different kits and affects the clinical accuracy of the different assays for CgA.

Fibrinogen metabolism in the lungs

The aim of this study was to evaluate the role of the pulmonary vessel endothelium in the metabolism of fibrinogen (FBG), by measuring the FBG, D-dimer, and fibrin(ogen) degradation product levels in the blood from pulmonary and radial arteries from 99 patients undergoing aortocoronary bypass. For comparison, protein C, protein S, and factor VII, were also measured. The results showed, with respect to the pulmonary arterial blood levels, significantly lower FBG levels (3.72 +/- 0.83 vs 3.66 +/- 0.81 g/L; P < .001) and higher fibrin(ogen) degradation product levels (7.36 +/- 1.53 vs 8.15 +/- 1.59 mg/L; P < .000 01) in the radial arterial blood. No difference was found for d -dimer, protein C, protein S, and factor VII. The study demonstrated that the pulmonary capillary endothelium contributes to the FBG catabolism for about a 0.02 fractional rate and support the view of an endothelial FBG catabolic pathway as the main catabolic pathway, owing to the fact that the pulmonary endothelial surface is about a 0.1 fraction of the peripheral vessel endothelial surface.

Comparative evaluation of two methods to assay thyroglobulin serum concentrations in patients with differentiated thyroid carcinomas

AIM

This study was aimed at the comparative assessment of the analytical and clinical performances of 2 tests for thyroglobulin (Tg) assays: the Dynotest Tg-Plus immunoradiometric assay (IRMA), a new method that might be of interest for its claimed superior sensitivity compared to other methods, and the HTGK-2 IRMA, one of the test currently used in clinical routine.

METHODS

The study was performed in serum samples from 157 patients with differentiated thyroid carcinoma (DTC). The clinical sensitivity of the test was evaluated in patients with and without thyroid stimulating hormone (TSH) suppression.

RESULTS

The lowest detectable Tg concentration values and the within-assay coefficient of variation (CV) were 0.4 and 0.8 microg/L and 5% and 3% for the Dynotest Tg-Plus assay and the HTGK-2 assay, respectively; the between-assay CV was 6% for both assays. The clinical results of the Dynotest Tg-Plus and those of the HTGK-2 kit were similar in both DTC patient populations, either under or off the TSH suppressive treatment. In spite of the manufacturer's statement that the calibrators of both assays had been standardized against the same common reference (standard CRM 457 of the Community Bureau of References), the Dynotest Tg-Plus test underrated by a factor of 0.5 the Tg values measured by means of HTGK-2 IRMA.

CONCLUSION

The sensitivity of the Dynotest Tg-Plus IRMA appears to be similar to that of the HTGK-2 assay.

Impact of fractures on health care in a major university hospital in Rome

BACKGROUND AND AIMS

The aim of the study was to investigate the impact of fractures (i.e., hip, Colles, humeral and vertebral fractures), compared with that of other common diseases requiring hospitalization, on health care in the main hospital in Rome (Italy).

METHODS

Hospital discharge forms, filled in according to the 9th International Classification of Diseases, were examined from 1996 to 1999. Data on fractures were compared with those related to other diseases which occupy a considerable proportion of hospital operating time in Italy: coronary heart disease (CHD), cerebrovascular disorders (CVD), diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD) and breast cancer (BC).

RESULTS

In all groups of patients, the mean age of females was significantly higher (p<0.0001) than that of males. Male patients with hip fractures had hospital stays significantly longer than females (p<0.0001), whereas women with Colles fractures had significantly (p<0.02) longer stays. When patients were divided according to age (i.e., over or under 60 years), mean hospital stays did not differ between younger and older patients in all groups except Colles fractures (p<0.001). Hip fractures in older patients showed striking in-hospital mortality. Throughout the study period, hip fractures accounted for the highest overall and per-patient costs. The number of female patients with fractures (and, obviously, breast cancer) was higher, while the opposite applied to the other disorders. Male patients with fractures, CHD and CVD were significantly younger than females (p<0.0001). When the percentage of deaths was added to that of patients discharged to other institutions, fractures showed the poorest outcome of any hospitalization event. Per-patient costs were remarkably higher for CHD, followed by fractures.

CONCLUSIONS

Fractures represent a growing but often underestimated burden for hospital care in Italy; further studies are needed on this issue.

Bone metabolism in ochronotic patients

We investigated skeletal involvement in five male and two female patients with ochronosis, aged 26-82 years. The main parameters of mineral metabolism, together with biochemical markers of bone resorption (urinary N-telopeptides of type I collagen) and formation (serum bone isoenzyme of alkaline phosphatase and serum osteocalcin) were evaluated. In the same subjects lumbar spine and femoral bone mineral density (BMD) were also measured by dual energy X-ray absorptiometry. All patients but the younger 26-year-old patient had lower than normal bone mass at femoral neck and total hip, showing marked osteopenia in three cases and osteoporosis in the remaining three cases. However, at lumbar spine BMD measurement provided spuriously overestimated results, because of intervertebral disc calcification and osteophyte formation. As far as biochemical markers of bone turnover are concerned, the most relevant finding was the increased N-telopeptides of type I collagen urinary excretion. Our results suggest that ochronosis may be associated with increased bone resorption rate leading to an accelerated bone loss. A role of the homogentisic acid polymer deposit in bone matrix and cells, possibly with osteocyte damage and interference in collagen metabolism, might be hypothesized.

Gallium scan in adolescents and children with Hodgkin's disease (HD). Treatment response assessment and prognostic value

AIM

The aim of the present paper is to describe the accuracy of gallium ((67)Ga) scintigraphy in adolescents and children with Hodgkin's disease (HD). We have studied the diagnostic value of this nuclear imaging technique at disease presentation (staging) and its prognostic value based on changes in (67)Ga uptake observed after treatment (response assessment).

METHODS

From April 1985 to July 1999 74 consecutive untreated patients with a median age of 13 y underwent (67)Ga scans 48-72 h after injection of 37-111 MBq of (67)Ga-citrate. Planar whole-body scintigraphy was performed, supplemented with single photon emission tomography (SPET) of the mediastinum from 1996 onwards. Three patients did not undergo further scintigraphic examination because they were treated with radical surgery. After the 1st examination 71 of the 74 patients were monitored by 1-3 (67)Ga scans during the course of their disease. All of them had at least one (67)Ga scintigraphy at the end of the induction phase of chemotherapy, before any other therapeutic regimens were planned.

RESULTS

At disease presentation (67)Ga scintigraphy was positive in all patients, detecting 285 of 335 (85.0%) lymph nodal sites of disease. The best sensitivity was observed in the mediastinum (100%; 63/63) and the laterocervical supraclavicular region (85.6%; 125/146); it was lower for axillary (72.7%; 16/22) and retroperitoneal (68.7%; 11/16) lymph node masses. In detecting visceral involvement the sensitivity of (67)Ga scintigraphy was 66.6% (8/12) for lung and 80% (4/5) for bone involvement. Among 71 patients in follow-up, 2 showed rapid progression of disease during induction therapy while 69 patients were monitored for a long period. The response to therapy has been classified according to the changes observed on nuclear medicine or radiological images as complete response (CR) or partial response (PR). On the basis of (67)Ga scans 55 patients (72.4%) were considered as having a CR, while with radiological modalities (chest X-ray, CT, MRI) CR was observed in only 29 patients (40.8%). PR or progression was found with (67)Ga scintigraphy in 16 patients (22.5%) and with radiological modalities in 42 patients (59.1%). (67)Ga scan was concordant with clinical outcome in 97% (28/29). The diagnostic effectiveness of this imaging technique has been analysed by comparing the scintigraphic or radiological changes at the 1st scintigraphic/radiological follow-up examination after induction therapy with the clinical outcome. In this population the relapse rate was 50% (8/16) in the group that did not achieve a CR according to post-treatment (67)Ga scintigraphy, while it was only 10.9% (6/55) in the group that achieved a CR on the basis of scintigraphy findings. The overall survival (OS) and disease-free survival (DFS) were calculated by means of Kaplan-Meier cumulative survival plotting. When the 2 groups of patients with complete (CR) or incomplete normalisation (PR or progression) of (67)Ga scintigraphy were compared, both OS and DFS were found to be statistically different (p=0.0001 and p=0.0004, respectively). By contrast, no statistical difference was found when the radiological findings were considered as the criterion for assessment of tumour response. On the basis of X-ray results the relapse rate was 13.7% in patients with negative post-therapy findings and 23.8% in patients with positive radiological imaging.

CONCLUSION

Our data demonstrate the high value of (67)Ga scintigraphy in HD staging in paediatric patients. In addition, evaluation of the (67)Ga uptake is very useful as a prognostic parameter; changes in (67)Ga uptake after therapy indicate a favourable prognosis, whereas children still positive on post-treatment (67)Ga scintigrams should be given more aggressive treatment.

Uneven deficits in vertebral bone density in postmenopausal patients with primary hyperparathyroidism as evaluated by posterior-anterior and lateral dual-energy absorptiometry

This investigation was undertaken to determine whether the preservation of bone mass in patients with mild primary hyperparathyroidism (PHPT) could be detected when measuring spine density in the lateral projection. We compared the bone mineral density (BMD) of L2-L4 utilizing the posterior-anterior (PA) and lateral projections in postmenopausal patients with PHPT and in a group of 27 postmenopausal normal women. Thirty-three consecutive postmenopausal patients with PHPT were studied; 25 were asymptomatic whereas the remaining 8 suffered complications related to the disease. Based upon the criteria established by the Consensus Conference on the Management of Asymptomatic PHPT, only 10 of the 25 asymptomatic patients could be considered affected by mild disease; the remaining patients were classified as having moderate disease. Patients with mild disease had mean lateral total BMD values (0.682 +/- 0.113 g/cm(2)) significantly higher than normal women (0.588 +/- 0.076, p<0.02) and patients with moderate disease (0.599 +/- 0.077, p<0.05). There were significant differences among the three groups in both PA L2-L4 and L1-L4 levels: patients with mild disease had significantly higher mean BMD values than patients with moderate disease and normal women, when either three or four vertebrae were considered. Interestingly, at this latter site, patients with moderate disease had significantly ( p<0.05) lower values than normal women. Our results indicate that patients with mild PHPT have a preservation of vertebral mass when compared with the other hyperparathyroid patients and normal women, when taking into account both the mainly trabecular portion and the whole vertebra. The finding that when the PA projection was assessed, BMD values of patients with moderate disease were significantly lower than those of normal women, might be attributed to the detrimental effect of raised parathyroid hormone levels on the cortical component of the vertebral body.

Age related prolactin secretion in men after fentanyl anaesthesia

The aim of this study was to investigate the role of age in the hormonal response to opiate anaesthetic fentanyl. In 90 patients undergoing aortocoronary bypass, 59.6 +/- 9.2 years mean age, 35-81 age range, prolactin (PRL), thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), luteinizing hormone (LH), human growth hormone (HGH), insulin-like growth factor I (IGF I), glucagon and insulin were measured in venous blood samples drawn from fasting patients immediately before, at 8 h in the morning, and 60 min after the induction of anaesthesia with 30 microg/kg intravenous fentanyl bolus, 30 min after a second 7 microg/kg fentanyl bolus. Results showed a higher 60 min PRL peak in older, >65 years, in respect to younger, < or =50 years, patients (57.6 +/- 23.3 vs. 40.6 +/- 13.8 microg/l, P<0.005), with a significant upward trend with age across the entire age span (r=0.32; P<0.002), while no difference by age was found for the basal concentrations. No differences were found between the respective basal and 60 min concentrations for the other hormones investigated. As expected, differences by age were found for FSH, higher in >65 and in 51-65-year-olds than in younger patients (for the basal values, respectively, P<0.02 and P<0.05); IGF I was lower in >65 in respect to < or =50 (P<0.02) and to 51-65-year-old patients (P<0.05), with a significant negative correlation with age (r=-0.33; P<0.005). The study shows an age related increase of PRL concentrations after fentanyl administration. It may be due to the reduction of the hypothalamic dopaminergic tone with aging. IGF I levels have been confirmed to be inversely correlated with age.

The lungs and platelet production

Several studies have suggested that thrombopoiesis may occur in the lungs. To investigate the role of the lungs in platelet production, we measured automated platelet parameters in blood from the pulmonary artery and the radial artery (n=125) or aorta (n=26) in patients undergoing aorto-coronary bypass. No significant differences were found between pulmonary and radial arterial blood with regard to platelet count (192.132 +/- 46.250 vs. 192.004 +/- 46.294 x 10(9)/l), mean platelet volume (11.03 +/- 1.04 vs. 11.03 +/- 1.03 fl), plateletcrit (0.212 +/- 0.051 vs. 0.212 +/- 0.051 x 10(-2)), platelet distribution width (14.48 +/- 2.16 vs. 14.47 +/- 2.08 fl) and platelet-large cell ratio (0.350 +/- 0.076 vs. 0.351 +/- 0.078). Similar results were obtained in comparisons between pulmonary arterial and aortic blood. A coefficient of linear correlation of 0.98 was found between the pulmonary and radial arterial and aortic platelet counts. These findings suggest that the platelet population entering the lungs was the same as the platelet population leaving them. Our results do not therefore support the theory of pulmonary platelet production.

Hormone metabolism in the pulmonary circulation

We measured hormonal levels in blood samples from pulmonary and radial arteries in 117 patients undergoing aorto-coronary by-pass surgery with the aim of investigating the role of the pulmonary vessel endothelium in hormone metabolism. Insulin and glucagon concentrations were significantly higher in pulmonary artery blood with respect to radial artery blood (73 +/- 65 vs. 65 +/- 47 pmol/l, p < 0.005, and 80 +/- 49 vs. 73 +/- 51 ng/l, p < 0.01, respectively), while no difference was found for growth hormone, prolactin, C peptide, insulin-like growth factor I, follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, parathyroid hormone, thyroglobulin, triiodothyronine, thyroxine, free triiodothyronine, and free thyroxine. Moreover, prolactin concentrations were more than twice the normal levels, this being an effect of propafol and the opiate fentanyl used for the general anesthesia. Assuming that the arteriovenous differences observed are a marker of peptide hormone degradation, our study has demonstrated that with similar kinetics insulin and glucagon secreted into portal circulation and escaping from hepatic extraction undergo further homeostatic removal of about 9-10 % in the pulmonary circulation before entering the general circulation.

Respiratory changes in human red cells

To investigate physiological respiratory changes in human red cells, we measured automated red cell parameters in samples from the pulmonary and radial arteries of 86 patients undergoing aorto-coronary bypass and from the pulmonary artery and the aorta in 23 patients. Our results showed higher mean corpuscular volume (88.53 +/- 5.06 fl vs. 88.12 +/- 4.94 fl, P < 0.000001), haematocrit (0.369 +/- 0.039 vs. 0.367 +/- 0.038, P < 0.0005), red cell distribution width (43.38 +/- 4.16 vs. 43.04 +/- 4.05 fl, P < 0.000001) and a lower mean corpuscular haemoglobin concentration (338.3 +/- 15.9 vs. 339.9 +/- 16.8 g/l, P < 0.005) in pulmonary arterial as compared to radial arterial blood. There were no differences with respect to haemoglobin concentration, red blood cell count, or mean corpuscular haemoglobin. Similar differences were observed between pulmonary arterial and aortic blood. Our results suggest cyclic respiratory modifications of red cell parameters attributable to the CO2 Jacobs-Stewart cycle.

HLA antigens in alkaptonuric patients

BACKGROUND

In alkaptonuric patients a disabling ochronotic arthropathy develops, due to the deposit of a pigmented polymer of homogentisic acid. Since in inherited diseases the clinical expressions may be multifactorial, involving genetic and environmental factors, where the HLA system may play a role, we studied HLA antigens in ochronotic patients.

METHODS

The study was carried out in 21 members of three families of six ochronotic patients and in two isolated ochronotic patients. The HLA typing has been done testing for antigens from loci A, B and C, by international standard microlymphocytotoxicity method, and for loci DR and DQ, by fluorescence method on immunologically isolated cells by means of antibody-coated microspheres. The chi square test was used for statistical analysis, with Yates correction due to the low number of observations.

RESULTS

Despite the limited number of subjects, due to the rarity of the disease, a significantly higher prevalence of HLA-DR7 antigen was found in the alkaptonuric patients when compared to a general population (p<0.02), suggesting a possible association, while the prevalence of HLA A, B, C and DQ showed no significant differences.

CONCLUSIONS

It might play a role in the pathophysiology and in the clinical expression of the disease.

Positron emission tomography (PET) and other nuclear medicine modalities in staging gastrointestinal cancer

Gastrointestinal (GI) cancers account for the second highest number of new tumor cases and deaths per year in the United States and Western Europe. The most frequently involved sites are, in descending order, the colorectum, stomach, pancreas, liver, bile duct, and esophagus. The most common tumor type is adenocarcinoma. Among the epithelial cancers, great attention has recently been given to the tumors of neuroendocrine origin. These concepts are relevant because nuclear medicine imaging is based on visualization by means of a particular uptake of radiolabelled tracers in cancer cells that concentrate the radioactive signal. This signal is detected and reconstructed in planar or tomographic images. Different radiopharmaceuticals have been proposed for diagnostic application in oncology (such as radiolabelled monoclonal antibodies (MAbs), receptor tracers, and positron-emitting radiopharmaceuticals), and they are currently used as tracers for tumor detection with different modalities and techniques. Most of these techniques demonstrate their clinical usefulness in the diagnosis of GI cancer. This work is not intended to be a comprehensive review of all the extensive experience and possibilities of nuclear medicine for the diagnosis of GI tumors; rather, it aims to summarize the current status of the most important approaches and their main indications in staging GI cancers.

Predictive Value of Thyroglobulin Changes for the Efficacy of Thyroid Remnant Ablation

The aim of this case-control study was to determine the utility of the evaluation of changes in serum thyroglobulin (Tg) levels before and after 131I diagnostic total body scan (TBS) in patients with thyroid cancer to predict the efficacy of radioiodine ablation. Among 134 consecutive patients with differentiated thyroid carcinoma (DTC) who had undergone a thyroidectomy and TBS prior to radioiodine ablation, we selected those subjects with no evidence of distant metastases and with two consecutive assessments of Tg before TBS and radioiodine ablation within a period of four weeks. With this selection procedure 27 patients (22 with papillary and five with follicular carcinomas) were included in our evaluation. The ablation therapy was considered successful when the TBS performed one year after treatment did not show any or less than 1% cervical 131I uptake, Tg levels remained below 3 ng/mL, and clinical and instrumental examinations were negative for the presence of relapses. These criteria divided the selected patients into two subsets: patients with successful radioiodine ablation and patients with residual thyroid tissue. The majority of patients with unsuccessful ablation showed an increase in serum Tg levels, while most of the patients with successful ablation showed a steady decrease in Tg concentrations. Statistical analysis evidenced that the increase in Tg levels after TBS was related to unsuccessful ablation (P ≥0.01). By contrast, the rate of thyroid remnants with 131l uptake did not show any relationship with the outcome of ablation therapy. The group of patients with increasing Tg levels after TBS had a relative risk of 3.3 of unsuccessful ablative therapy compared to the group with stable or decreasing Tg levels. This study supports the concept that by monitoring Tg levels in patients who undergo diagnostic TBS before radioiodine ablation it is possible to obtain useful information about the efficacy of 131l therapy.

Exogenous glucocorticoids affect in different way the various phases of bone formation in postmenopausal patients

BACKGROUND

To determine the effect of glucocorticoid excess on the most important circulating markers of bone formation in postmenopausal treated patients.

METHODS

The study included 15 postmenopausal women taking glucocorticoids for various medical conditions and two groups of 30 healthy premenopausal and 28 age-matched postmenopausal women as controls. Osteoblastic activity was assessed by measuring both serum levels of osteocalcin (BGP) (N-tact Osteo SP, Incstar Co.) and the bone-specific isoenzyme of alkaline phosphatase (BAP) (Alkphase-B, Metra Biosystems).

RESULTS

The mean values of serum BGP found in patients taking steroids were significantly reduced as compared to those found in both fertile and postmenopausal women (p < 0.0001). The mean serum levels of BAP were significantly increased in treated patients as compared to premenopausal women (p < 0.0001), while no significant difference was found between patients and age-matched postmenopausal women. Similar results were also obtained when individual values of both serum BAP and BGP were expressed as standard units in comparison to values obtained in fertile subjects (T-score) or postmenopausal subjects (Z-score).

CONCLUSIONS

Steroid therapy in postmenopausal patients differentially affects the various phases of bone formation. Measurement of serum BGP may represent a reliable parameter for monitoring bone formation in postmenopausal treated patients.

Role of monocytes in the early phase of acute myocardial infarction

BACKGROUND

In acute myocardial infarction peripheral leucocytosis occurs early and fibrinogen levels increase in response to the tissue injury, expressed by the enhanced enzyme plasma levels. The aim of the present study has been to investigate if a unifying link between these modifications might be found.

METHODS

In 325 patients, 246 men and 79 women, 61.46 +/- 11.00 and 70.03 +/- 11.30 years mean age respectively, at admission for myocardial infarction and before treatment, we simultaneously measured plasma fibrinogen (FBG), hemochromocytometric parameters and plasma enzyme aspartate and alanine transaminase (AST and ALT), lactate dehydrogenase (LDH) and creatine phosphokinase (CPK). The statistical analysis was performed by using standard multiple regression for dependent variable FBG and for the variables white blood cells (WBC), monocyte number, large unstained cells (LUC) and CPK.

RESULTS

The results showed that FBG was significantly correlated with monocyte (p < 0.001) and LUC (p < 0.05) counts; assumed as dependent variable, further on with FBG, monocyte number was correlated with WBC count, LUC and CPK; further on with monocyte number, WBC with neutrophile and lymphocyte counts, LUC with CPK, CPK with LDH.

CONCLUSIONS

The study seems to show that monocyte modifications occur already in the early phase of myocardial infarction. These modifications are directly related to damage extension, as deducible from CPK levels, and seem to mainly modulate FBG and WBC, since the cytokines and hematopoietic growth factors production by activated monocytes.

[Osteoporosis and phytoestrogens: an assessment of bone mineral density via quantitative peripheral computed tomography in milk-egg-vegetarian women in the premenopause]

PURPOSE

Noninvasive assessment of bone mineral density, geometrical and biomechanical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with "Mediterranean" dietary intake lacking in these substances.

MATERIAL AND METHODS

Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated in 15 female subjects with phytoestrogens dietary intake. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Fifteen age-matched subjects with "Mediterranean" dietary intake were chosen as a control group. Cross-sectional area (Total A), trabecular area (TA), cortical area (CA), cortical thickness (CThk) and strength strain index (SSI) were assessed as biomechanical parameters.

RESULTS

Daily consumption of phytoestrogens was significatively different in the two groups (phy: 17.45 mg/die vs ctr: 0.35; p < 0.0005), while calcium intake was similar (phy: 652 mg/die vs ctr: 650). Total (0.460 g/cm3 vs ctr: 0.433) and trabecular (phy: 0.209 g/cm3 vs ctr: 0.189) bone mineral densities, such as SSI (phy: 925 mm3 vs ctr: 894) values, were higher in women with dietary intake of phytoestrogens, in comparison with the relative controls, but not significantly (p = ns). Among geometrical parameters, total area and cortical area were tendential in women with a vegetarian diet while cortical thickness was the same in both groups.

CONCLUSIONS

pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal women with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are warranted to evaluate definitively the efficacy of phytoestrogens in preventing postmenopausal osteoporosis.

Osteocalcin metabolism in the pulmonary circulation

The aim of this study was to evaluate the role of the pulmonary vessel endothelium in the removal of circulating osteocalcin, by measuring the osteocalcin levels in serum from pulmonary and radial artery blood from 39 patients undergoing aorto-coronary bypass. Because of the discrepancies between methods of measurement, two methods were used. Significant differences were observed in group A (n = 18), tested with heterologous radioimmunoassay (2.85 +/- 0.67 microg l-1 in the pulmonary versus 2.69 +/- 0.67 microg l-1 in the radial artery serum, P<0.001) and in group B (n = 21), tested with a two-site immunoradiometric assay (5.22 +/- 1.46 versus 4.93 +/- 1.36 microg l-1, P<0.01). The percentage differences were -5.54 +/- 4.76% (P<0.001) in group A and -4.99 +/- 8.13% (P<0.01) in group B; the comparison between the percentage differences was not significant. These different osteocalcin concentrations between the two vascular compartments were considered a marker of osteocalcin degradation. Therefore, the study seems to demonstrate that, as well as kidney, liver and bone, the lung is a relevant site of osteocalcin catabolism. The proteolytic activity of pulmonary vessel endothelium seems to involve about 5% of the circulating peptide.

[Assessment of geometric, biomechanical, and osteodensitometric properties of the ultradistal radius with peripheral quantitative computerized tomography in uremic patients with severe hyperparathyroidism]

INTRODUCTION

Bone integrity and mineral status were studied with a noninvasive method in uremic patients with severe secondary hyperparathyroidism undergoing maintenance hemodialysis.

MATERIAL AND METHODS

Volumetric cortical and trabecular mineral density (cBMD, tBMD) and bone geometrical properties were evaluated in 16 patients (11 women and 5 men) candidate to parathyroidectomy. Peripheral quantitative Computed Tomography (pQCT) was used to make measurements at the distal radius of the nondominant forearm. Thirty-two age-matched healthy subjects were chosen as a control group. Cortical area (CA), cross-sectional area (Total A), cortical thickness (CThk) and stress strain index (SSI) were assessed as biomechanical parameters. Serum intact PTH levels were assessed with a radioimmunoassay method (IRMA).

RESULTS

Both cBMD and tBMD were decreased in all patients and the difference was more significant in women (p < .0004 and p < .009) than in the smaller group of men (p < .01 and p < .01). Serum PTH levels correlated negatively with cBMD (r = .52; p < .01), CThk (r = .51; p < .04), CA (r = .52; p < .03) and SSI (r = .54; p < .02), as well as tBMD (r = .34), though not significantly. Dialysis duration did not significantly correlate with cBMD (r = .33), tBMD (r = .20), CA (r = .31), CThk (r = .40) and SSI (r = .35). As for geometrical and biomechanical parameters, CA, CThk and SSI were significantly different in both male and female uremic patients in comparison with the relative controls. Bone quantitative analysis and three-dimensional (3D) representation with the paraboloid revolution model also demonstrated osteopenia.

CONCLUSIONS

pQCT shows significant cortical and trabecular osteopenia in uremic patients with severe secondary hyperparathyroidism. Osteopenia is associated with geometrical and mechanical impairment with consequently increased bone fragility and thus a higher risk of fracture. Prolonged PTH hyperexpression seems to be mainly associated with intracortical porosity and cortical-endosteal resorption. Bone quantitative analysis and 3D representation provide rapid automated information on the cortex mineral status.

Lactate dehydrogenase and its isoenzymes in the marrow and peripheral blood from haematologically normal subjects

Lactate dehydrogenase (LDH) activity and its isoenzymatic fractions were measured in bone marrow blood and in peripheral venous blood from 16 haematologically normal subjects. Total LDH activity was significantly higher in marrow than in venous blood (428.8 +/- 98.4 vs 260.1 +/- 40.2 mU/l, p < 0.0001). The same was true for the absolute values of its isoenzymatic fractions. The percentage fractions LDH 1 and LDH 5 were similar in the two regions, while LDH 3 and LDH 4 were higher in medullary blood (p < 0.05) and LDH 2 was higher in peripheral blood (p < 0.05). The Spearman test showed a limited correlation between marrow and peripheral total LDH activity values (p < 0.05). This seems to be at least in part sustained by the highly significant correlations existing in LDH 3 and LDH 4 values, reported to be pre-eminent isoforms in maturing haematopoietic cells (p < 0.005 and p < 0.001, respectively). These findings could be attributed to an apoptotic regulation of marrow cell production.

Assessment of serum total and bone alkaline phosphatase measurement in clinical practice

The aim of the study was to measure serum levels of the bone-specific isoenzyme of alkaline phosphatase in normal subjects and patients with metabolic bone disease by using an immunoadsorption assay. We studied 140 healthy adults, 122 patients affected by metabolic bone disease and 15 patients with cholestatic liver disease. Mean values of the bone-specific isoenzyme of alkaline phosphatase in healthy men were significantly higher than those found in premenopausal women (17.8 +/- 4.2 U/l vs 15.6 +/- 4.6 U/l, p < 0.02); postmenopausal women had significantly higher levels of bone-specific isoenzyme of alkaline phosphatase (22.6 +/- 6.4 U/l) than premenopausal women (p < 0.0001). After the menopause total alkaline phosphatase increased by 46%, while the increase in bone-specific isoenzyme of alkaline phosphatase was 39%. No significant correlations were found between bone-specific isoenzyme of alkaline phosphatase and either age or years since menopause, in postmenopausal subjects. In patients with bone-specific isoenzyme of alkaline phosphatase above the upper limit of normal, the assay had a sensitivity of 100% only in patients with Paget's disease of bone. In patients with cholestatic liver disease we found no correlation between bone-specific isoenzyme of alkaline phosphatase and either total alkaline phosphatase and gamma-glutamyl transpeptidase, while a positive correlation was found between total alkaline phosphatase and gamma-glutamyl transpeptidase. Our results confirm the role of bone-specific isoenzyme of alkaline phosphatase assay in clinical research; however, its usefulness in clinical practice is unclear once liver involvement has been excluded.

Heat inactivable fraction of alkaline phosphatase in marrow and peripheral blood

We measured the total alkaline phosphatase activity and their heat-inactivable and heat-stable fractions both in marrow and in peripheral blood, collected from 16 patients undergoing bone marrow aspiration for diagnostic purposes. Total enzymatic activity and the heat-inactivable fraction, of bone source, were significantly higher in serum from medullary blood (p < 0.001). Although the heat-stable fraction, of non-bone source, was higher in serum from peripheral blood (p < 0.05), the inactivable fraction showed there the greater component (51.56 +/- 11.91%). Results seem to indicate that the quantification of the enzymatic fractions and of the ratios between them in comparison with marrow and peripheral blood may be useful in cases that pose diagnostic difficulties.

The measurement of urinary amino-terminal telopeptides of type I collagen to monitor bone resorption in patients with primary hyperparathyroidism

This study was carried out in order to evaluate clinical usefulness of cross-linked N-telopeptides (NTx) of type I collagen determination, in patients with primary hyperparathyroidism. Twenty-six consecutive patients (6 males and 20 females, aged 56.3 +/- 15.0, SD, yrs) with primary hyperparathyroidism were studied in basal conditions and, ten of them, after surgical cure of the disease. Cross-linked collagen peptides were measured by enzyme-linked immunosorbent assay and conventional markers of bone turnover according to standard procedures. Bone densitometry at the lumbar spine and proximal femur was performed using dual-energy X-ray absorptiometry. Bone mineral density, was also assessed at the junction of the distal and middle third of the radius and at the ultradistal radius of the non-dominant arm by a dual photon densitometer. Mean urinary NTx values (194.2 +/- 121.9 pmoles bone collagen equivalents/mumoles creatinine) were significantly higher (p < 0.001) in respect to those found in normal subjects. The mean increase of Z score values of both serum tartrate resistant acid phosphatase activity (1.4 +/- 1.8) and the fasting hydroxyproline/creatinine ratio (1.45 +/- 2.0) was significantly lower (p < 0.02) in respect to that of NTx Z score values (3.3 +/- 3.3); the latter values were not significantly different than mean Z score values of serum osteocalcin (4.0 +/- 3.9), serum alkaline phosphatase activity (2.6 +/- 2.6) and urinary calcium/creatinine ratio (3.2 +/- 3.3). We found a significant inverse correlation between NTx values and both lumbar spine (p < 0.01) and ultradistal radius bone mineral density (p < 0.05); a modest inverse correlation was also observed between serum tartrate resistant acid phosphatase activity and lumbar spine bone mineral density (p < 0.04). Following successful adenoma removal, the percentage decrease of both NTx and hydroxyproline was similar in patients with increased bone turnover rate; major discrepancies were observed in patients with normal values of NTx, the telopeptide reduction being greater than that of hydroxyproline. Finally, in a hypercalcemic patient with metastatic parathyroid cancer, telopeptide excretion was shown to be more sensitive in respect to urinary hydroxyproline when evaluating the effects of antiresorptive therapy. Our results seem to indicate that amongst the markers with good sensitivity, NTx is the only one that is inversely related with bone mineral density at two different skeletal sites. This assay should therefore have a place in both the initial screening and medical follow-up of patients with this glandular disorder; in fact, in both situations an increased urinary excretion of this marker should warn about the possibility of hidden bone loss.