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O Schillaci

Publications and source records attributed to O Schillaci.

At least 19 recordsLinked to original sources
PubMed2000

Long-term octreotide treatment of metastatic carcinoid tumor.

The optimal dosage of somatostatin analogs for the long-term control of carcinoid tumors has not yet been established. Receptor alterations induced during long term treatment with somatostatin analogs have lead to consecutive drug dosage increases in order to control carcinoid disease. In this report, we describe the rapid and effective control of tumor in a patient with metastatic carcinoid treated for nine years with a single daily dose of octreotide based on tumor marker levels. Tumoral somatostatin receptor (sst) subtype analysis by RT-PCR amplification showed the expression of sst2 subtype only. We suggest that a single daily dose of octreotide strictly related to tumor marker secretion, could have played a role in the effective long-term therapy by avoiding the phenomenon of somatostatin receptor desensitisation. Furthermore, the exclusive presence of sst2 subtype supports the high affinity of octreotide to tumoral cells.

Antineoplastic Agents, Hormonal↗
PubMed2000

111In-pentetreotide scintigraphy in the detection of insulinomas: importance of SPECT imaging.

UNLABELLED: The aim of this study was to determine whether the systematic use of SPECT can increase the reported low sensitivity of somatostatin receptor scintigraphy (SRS) in detecting insulinomas. METHODS: Fourteen patients were evaluated. After 111In-pentetreotide injection (approximately 250 MBq intravenously), abdominal SPECT images were obtained at 4 h and multiple planar images were obtained at 4 and 24 h. MRI and CT were performed within 1 mo of SRS. Sixteen tumors were histologically verified after surgery in 14 patients. RESULTS: SPECT revealed 14 lesions in 12 patients (sensitivity, 87.5%), both planar SRS and MRI revealed 7 tumors in 7 patients (sensitivity, 43.8%), and CT revealed only 5 lesions in 4 patients (sensitivity, 31.3%). Moreover, in 4 patients SPECT was the only examination with positive findings. CONCLUSION: SPECT at 4 h is mandatory for preoperative detection of insulinomas using SRS because the images are more sensitive than planar images and are superior to images from other conventional methods.

Female↗
PubMed1999

Technetium-99m sestamibi single-photon emission tomography detects subclinical myocardial perfusion abnormalities in patients with systemic lupus erythematosus.

In patients with systemic lupus erythematosus, involvement of the cardiovascular system is the third leading cause of death. However, although autopsy studies have demonstrated a high incidence of abnormalities in both the myocardium and coronary vessels, clinical manifestations have been reported in only a small percentage of cases. The aim of this study was to evaluate myocardial perfusion in asymptomatic lupus patients using technetium-99m sestamibi single-photon emission tomography (SPET). Twenty-eight patients without overt cardiac involvement and risk factors were studied with 99mTc-sestamibi SPET at rest and after dipyridamole infusion. Perfusion abnormalities were detected in 18 cases: six had persistent defects, three had reversible defects, seven had both persistent and reversible defects, and two showed rest defects which normalized on dipyridamole images ("reverse redistribution pattern"). Coronary angiography was performed in eight patients with positive 99mTc-sestamibi SPET, and showed normal epicardial vessels in all the cases. These results indicate that 99mTc-sestamibi SPET reveals a high prevalence (18 out of 28 patients in this study, i.e. 64%) of myocardial perfusion abnormalities in asymptomatic lupus patients, probably due to the primary immunological damage of this autoimmune disease. In conclusion, rest/dipyridamole 99mTc-sestamibi SPET can be a useful non-invasive method to identify subclinical myocardial involvement in systemic lupus erythematosus, and patients potentially at risk of later cardiac events.

Adult↗
PubMed1999

Technetium-99m tetrofosmin single photon emission computed tomography in the evaluation of suspected lung cancer.

Technetium-99m-tetrofosmin is a radiopharmaceutical employed for myocardial imaging, which has recently emerged as useful in the visualization of tumors. In this study technetium-99m-tetrofosmin was evaluated for its accuracy in differentiating malignant from benign pulmonary lesions, and in detecting mediastinal node metastasis due to lung cancer. Eighty-one patients with a solitary lung lesion on the chest radiograph and/or CT scan were submitted to chest single photon emission computed tomography after technetium-99m-tetrofosmin injection (740 MBq i.v.). The scintigraphic findings were correlated to the final histopathological diagnosis, demonstrating abnormal tracer accumulation in 51 of 54 malignant lesions (sensitivity 94%) and in 4 out of 27 benign conditions (specificity 85%), yielding an accuracy of 91%. Mediastinal lymph-node involvement was evaluated in 35 patients with non small cell lung cancer who underwent mediastinoscopy and/or surgery. Tetrofosmin accuracy (89%) was significantly higher than that of CT (69%, p < 0.05); the false negative scintigraphic results were in nodes sized less than 1 cm. In conclusion, technetium-99m-tetrofosmin imaging is useful in distinguishing malignant from benign pulmonary lesions, and in non-invasively assessing mediastinal node metastases from non small cell lung cancer, especially in patients with enlarged nodes by CT scan.

Adult↗
PubMed1999

Immunoscintigraphy of venous thrombi: clinical effectiveness of a new antifibrin D-dimer monoclonal antibody.

Safety and thrombus imaging capabilities of the 99mTc-labeled form of a new F(ab')2 monoclonal antibody (MoAb) against fragment D dimers from cross-linked human fibrin, previously shown to be effective labeled to 131I in detecting venous thrombi in the rabbit, were investigated. Sixteen patients (seven men, mean age: 60+/-7 years) with deep (n = three) and superficial (n = 13) venous thromboses of the lower limbs documented at echo-Doppler study underwent, 24 hours before saphenous vein stripping, a scintigraphic study after IV injection of the 99mTc-MoAb (1,129+/-275 MBq/mL), acquiring dynamic images, as well as early and delayed static images of lower limbs. Tracer activity was compared in normal and pathologic areas. At the operation, vessel wall including the thrombotic lesion was isolated, weighed, and counted. Blood radioactivity and MoAb concentration were also measured. No adverse reaction was observed after MoAb administration. Thrombus site appeared as a focal area (hot spot) of asymmetrically increased tracer uptake, already detectable at early images in all patients. All thrombi detected at echo-Doppler study (n=25) were confirmed at scintigraphic study, which showed four additional hot spots subsequently confirmed to represent thrombi at operation. Average percent ratio between pathologic and normal regions was 1.51+/-1.34 (p < 0.05) at time-activity curves, 2.27+/-1.1 (p < 0.05) at early static images, and 2.15+/-1.2 (p < 0.05) at delayed images, respectively. Thrombus-to-blood uptake ratio was 4.3+/-0.9 (p < 0.01). The F(ab')2 MoAb proved to be safe, and low levels of antimouse antibodies were detected in response, although further studies are needed to assess tolerance and effectiveness in case of a second administration in the same patient. The 99mTc-labeled MoAb was very effective in identifying venous thromboses both at deep and superficial localizations, although its sensitivity and specificity need be evaluated in a more numerous group, including also patients with different and clinically more relevant localizations, such as caval thromboses. However, the possibility of obtaining high-quality images within 4 hours of MoAb administration is clinically relevant, and carries also therapeutic implications, especially in pulmonary thromboembolism.

Antibodies, Monoclonal↗
PubMed1999

Lupus carditis: evaluation with technetium-99m MIBI myocardial SPECT and heart rate variability.

The objective of this paper was to investigate the incidence of myocardial perfusion defects in patients with systemic lupus erythematosus (SLE) associated with dysautonomic alterations. Twenty patients without any sign or symptoms of heart disease, selected from a larger population of patients with SLE, underwent technetium-99m sestamibi (Tc-99m MIBI) single photon emission computed tomography (SPECT), at rest and after dipyridamole infusion; they also underwent heart rate variability (HRV) examination by a 24 hour ambulatory electrocardiography, analyzing in the time domain the standard deviation of the R-R intervals average (SDNN) and the percentage of R-R adjacent intervals differing from each other more than 50 msec (pNN50); in the frequency domain the low (LF) and high frequencies (HF) were analyzed. Twenty healthy volunteers served as control group for heart rate variability. At MIBI-SPECT examination, the scan was found abnormal in 15 patients and normal in five: three patients demonstrated reversible defects in the anteroseptal region, four had irreversible defects in a region (two in the anteroseptal region and two in the lateral region), two had rest defects in two different regions (lateral and inferior, lateral and anteroseptal) that improved during dipyridamole scan, and six had both reversible and irreversible defects: four in a single segment (three anteroseptal and one lateral, and two in two different regions, particularly anteroseptal and lateral, lateral and inferior). All 20 patients showed significantly lower HRV parameters in comparison with the control group, except for pNN50, which indicates decreased physiologic periodic fluctuations of the autonomic nervous system. In six patients who underwent coronary angiography, the epicardial vessels were found completely normal. In view of the high incidence of myocardial hypoperfusion in patients with HRV alterations, the authors hypothesize that autonomic dysfunction may be associated with microvascular disease or metabolic alteration. They also believe that MIBI scintigraphy is a suitable technique in detecting myocardial damage in SLE patients free of clinical manifestation.

Adolescent↗
PubMed1999

Single photon emission computed tomography procedure improves accuracy of somatostatin receptor scintigraphy in gastro-entero pancreatic tumours.

In patients with gastro-enteropancreatic neuroendocrine tumours the localization of all the neoplastic lesions and an accurate staging of the diseases have important therapeutic implications. Somatostatin receptor scintigraphy with In-111 pentatreotide has proved to be useful in detecting gastro-enteropancreatic tumours; however, the role of abdominal single photon emission computed tomography has not yet been definitively established. In a series of 52 patients with gastro-enteropancreatic tumours (9 non-functioning islet cell carcinomas, 4 insulinomas, 3 somatostatinomas, 2 VIPomas, 1 glucagonoma and 33 carcinoids) we compared somatostatin receptor scintigraphy with the results of computed tomography and magnetic resonance imaging performed within one month. Four and 24-hour total body planar images and 4-hour abdominal single photon emission computed tomography were acquired after the i.v. injection of approximately 250 MBq of In-111 pentatreotide. Only abdominal localizations were considered: planar scans detected 16 extrahepatic lesions in 13 patients and 54 liver sites in 21 patients; single photon emission computed tomography visualized 31 extrahepatic lesions and 89 liver metastases in 27 and 28 patients, respectively; computed tomography and magnetic resonance imaging detected 11 extrahepatic lesions in 10 patients and 73 liver sites in 21 patients. In-111 pentatreotide single photon emission computed tomography was the only imaging method able to localize tumoural lesions in 13 patients; all these localizations were then histologically verified. The scintigraphic positivity did not depend on the site or on the presence of hormonal hypersecretions. In conclusion, our results indicate that single photon emission computed tomography is more sensitive than planar images and computed tomography/magnetic resonance imaging in detecting abdominal gastro-enteropancreatic tumours and their metastases; it is able to increase both the number of visualized lesions and that of patients with positive findings. Single photon emission computed tomography is particularly useful in patients in whom tumoural lesions have not been already localized; it should be the first imaging modality in patients with gastro-enteropancreatic tumours: its initial use will result in more information and proper management.

Female↗
PubMed1998

Preoperative identification of viable myocardium: effectiveness of nitroglycerine-induced changes in myocardial Sestamibi uptake.

In order to predict tissue viability in infarcted myocardial areas, changes induced by nitroglycerine infusion on Sestamibi myocardial uptake were evaluated in 37 patients with previously confirmed myocardial infarction undergoing coronary artery bypass grafting, and compared with echocardiographic and perfusional changes occurring after the operation. The improvement of Sestamibi uptake after nitroglycerine correctly classified 24/26 (92%) patients showing postoperative improvement of wall motion in the infarcted area, whereas 24/31 (77%) patients with nitroglycerine-induced increase in Sestamibi uptake had improved wall motion after operation. The presence of collateral flow to the infarcted area was associated with a significantly (P < 0.01) higher increase in Sestamibi uptake both during nitroglycerine infusion and postoperatively. An increase in wall motion score after operation was associated with a significantly higher (P < 0.05) increase in Sestamibi uptake score during nitroglycerine infusion. Thus, the results of this study suggest that Sestamibi perfusional myocardial scintigraphy during nitroglycerine infusion is capable of assessing viable but chronically hypoperfused myocardium and predicting postoperative wall motion and perfusional improvement, to yield the best results in patients with evidence of collateral circulation that supplies the infarcted area.

Aged↗
PubMed1998

Functional and ultrastructural evidence of myocardial stunning after acute carbon monoxide poisoning.

OBJECTIVE: To study human myocardial ultrastructural changes after carbon monoxide (CO) poisoning inducing reversible cardiac failure. DESIGN CASE REPORT: clinical, functional and morphologic findings. SETTINGS: Public university-affiliated hospital and electron microscopy laboratory. PATIENT: A 25-yr-old woman with functional evidence of cardiac failure after acute CO poisoning. INTERVENTIONS: Hyperbaric and intensive care treatment over 10 days. Scintigraphic and cardiac angiography with endomyocardial biopsy. MEASUREMENTS AND MAIN RESULTS: Scintigraphy with 99mTc hexakis 2-methoxy-2-isobutyl isonitrile (sestaMIBI) showed an uptake defect in the left anterior descending artery territory. The cardiac angiography demonstrated a slight hypokinesis of the superior two thirds of the anterior wall and of the septal region with completely normal coronary angiograms. Electron microscopy of left ventricular biopsies showed slight ultrastructural changes in the myocytes. In addition, large glycogen deposits were mostly associated with swollen mitochondria. The patient was discharged in good clinical condition on day 10. CONCLUSIONS: Presence of glycogen deposits associated with abnormal mitochondria may be signs of the incapability of myocardial cells in utilizing energy substrata. In the presence of normal myocardial perfusion, our findings are consistent with the presence of a stunned myocardium-like syndrome. Early recognition and treatment of this clinical syndrome allow the prevention of myocardial infarction.

Adult↗
PubMed1998

Noninvasive estimate of bile flux through the gallbladder in humans.

OBJECTIVE: The aim of this study was to assess whether a single noninvasive technique, ultrasonography, is able in vivo: 1) to evaluate the time-related patterns of gallbladder bile storage and emptying, and 2) to quantitate the amount of bile flux through the gallbladder (GB). METHODS: Healthy volunteers were submitted to the simultaneous assessment of gallbladder volume variations by frequent serial ultrasonographic (US) measurements and of hepatic bile flow through the GB by quantitative cholescintigraphy (QC) during continuous i.v. infusion of 99 mTc-HIDA. An ad hoc mathematical analysis of US GB volume measurements was used to estimate the amount of bile flux through the GB. The QC-derived measurements of the flux of hepatic bile through the GB was used to substantiate the US-derived estimates. RESULTS: The curves expressing the time-related GB handling of hepatic bile obtained independently from US and QC measurements were statistically equivalent, and both techniques showed that the patterns and the amount of hepatic bile handled by the gallbladder after meal ingestion is remarkably different during three successive phases. After meals, hepatic bile was mainly 1) stored in the GB in the first phase; 2) emptied from the GB in a second phase; and 3) stored in the GB in the third phase. The ultrasonographic analysis estimated that 1) 23.8+/-12.5 ml (0.44+/-0.11 ml/min), 5.1+/-3.9 ml (0.15+/-0.10 ml/min), and 33.2+/-10.5 ml (0.53+/-0.16 ml/min) of hepatic bile entered into the GB during the three successive postprandial phases, and 2) the entire amount of bile flowing bidirectionally through the cystic duct, during the observation period (132.6+/-23.3 ml) was about five-fold greater than that estimated by the usually employed variables. CONCLUSION: The proposed mathematical analysis of frequent ultrasonographic measurements of the GB volumes enables one to estimate noninvasively the flux of bile through the gallbladder in humans.

Adult↗
PubMed1998

Use of the somatostatin analogue octreotide to localise and manage somatostatin-producing tumours.

BACKGROUND: Somatostatin receptor scintigraphy (SRS) and octreotide therapy have both changed the management of gastroenteropancreatic endocrine tumours, but very few data are available on the use of SRS and octreotide to visualise and treat somatostatinomas. METHOD: The results of SRS and octreotide treatment in three somatostatinoma patients were examined. RESULTS: SRS was able to detect extensive hepatic involvement in patient 1, one hepatic and one pancreatic lesion in patient 2, and one hepatic lesion in patient 3. Octreotide therapy (0.5 mg/day subcutaneously) was effective in decreasing plasma levels of somatostatin in all three patients. Symptoms (diabetes and diarrhoea) were greatly improved in the two patients with "somatostatinoma syndrome". CONCLUSION: The study shows that somatostatinoma, like most other gastroenteropancreatic endocrine tumours, possesses functioning somatostatin receptors.

Aged↗
PubMed1997

Technetium-99m sestamibi myocardial tomography based on dipyridamole echocardiography testing in hypertensive patients with chest pain.

The non-invasive diagnosis of coronary artery disease in hypertensives with chest pain is an important clinical concern because all exercise-dependent tests display limited feasibility and diagnostic accuracy; by contrast, dipyridamole echocardiography testing has been shown to have a similar feasibility and accuracy in hypertensive and normotensive subjects. The aim of this study was to evaluate the diagnostic capability of technetium-99m sestamibi tomography based on dipyridamole echocardiography testing in hypertensives with chest pain, and to compare the scintigraphic results with those of coronary angiography, exercise electrocardiography and dipyridamole echocardiography. Forty subjects with mild to moderate hypertension, chest pain and no previous myocardial infarction were submitted to 99mTc-sestamibi tomography (at rest and after high-dose dipyridamole echocardiography) and to exercise electrocardiography testing. At coronary angiography 22 patients (group A) had significant epicardial coronary artery disease (>/=70% stenosis of at least one major vessel) and 18 normal main coronary vessels (group B). Dipyridamole 99mTc-sestamibi imaging was positive in 21/22 patients of group A and in 5/18 of group B. Dipyridamole echocardiography was positive in 18/22 patients of group A and in 5/18 of group B. Exercise electrocardiography was positive in 15/22 patients of group A and in 11/18 of group B. Four out of five subjects in group B with positive results in all the tests showed a slow run-off of angiographic contrast medium, probably due to small-vessel disease. Significant epicardial coronary artery disease in hypertensives with chest pain is unlikely when dipyridamole 99mTc-sestamibi tomography is negative. When scintigraphy is positive, either epicardial coronary artery disease or a small-vessel disease condition is possible. The association of scintigraphy with dipyridamole echocardiography testing allows the assessment of contractile function and myocardial perfusion by a single pharmacological stress.

Chest Pain↗
PubMed1997

Somatostatin receptor scintigraphy of malignant somatostatinoma with indium-111-pentetreotide.

This article describes the visualization of a pancreatic somatostatinoma and liver metastases using 111In-pentetreotide imaging in a patient with somatostatinoma syndrome. A 61-yr-old woman with gallbladder stones, diabetes, weight loss, diarrhea and steatorrhea, immunohistochemical diagnosis of somatostatinoma (liver biopsy) and high plasma values of somatostatin was studied by somatostatin receptor scintigraphy. Six sites of focal abnormal 111In-pentetreotide hyperfixation were found: three in the liver and three in the pancreatic area. This case report demonstrates that in vivo detection of somatostatinoma with somatostatin receptor imaging is possible in the presence of high levels of circulating somatostatin, suggesting that receptor downregulation has not occurred.

Female↗