technetium-tc-99m-depreotide and Lung-Diseases

The use of gallium for pulmonary diseases is hampered by its relative lack of specificity, typical 1- to 3-day delay between injection and imaging time, and suboptimal imaging characteristics. Other nuclear and nonnuclear imaging modalities, such as (18)F-fluorodeoxyglucose positron emission tomography (PET) and high-resolution chest computed tomography, have replaced gallium in many clinical algorithms. Yet gallium and other radiotracers, such as thallium, sestamibi, and labeled white blood cells, are useful in many specific clinical situations involving lymphoma and other neoplasias, inflammatory processes such as sarcoid and interstitial pneumonia, tuberculosis and other infections, and the acquired immune deficiency syndrome. Gallium and some of the other single-photon agents still have value in establishing a diagnosis, assessing the location and extent of disease, differentiating active disease from chronic scarring, guiding potential biopsy, and determining recurrence and response to therapy in patients with certain lung diseases, particularly when access to PET imaging is not available.

Topics: 3-Iodobenzylguanidine; AIDS-Related Opportunistic Infections; Citrates; Gallium; Gallium Radioisotopes; Humans; Indium Radioisotopes; Intercellular Signaling Peptides and Proteins; Iodine Radioisotopes; Leukocytes; Lung Diseases; Lung Neoplasms; Peptides; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin; Somatostatin; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tuberculosis, Pulmonary

Indeterminate lung nodules (LN) constitute a clinical problem of increasing frequency that requires an effective diagnostic approach. This study evaluates the contribution of 99mTc-depreotide scintigraphy in the management of such patients. Forty (40) patients (27 males/13 females) 29 to 82 years old (61 +/- 12) with lung nodules/masses of indeterminate origin on computed tomography (CT) images were injected with 99mTc-depreotide and underwent thoracic tomography (single photon emission computed tomography) 2 and 4-4.5 hours later. All parenchymal lesions (50) identified by CT were scored as negative or positive as to the uptake of 99mTc-depreotide. Positive images were also evaluated semiquantitatively. Thirty (30) of 31 malignant lesions were positive (97% sensitivity) and 12 out of 19 benign lesions were negative (63% specificity), with positive images obtained in benign processes such as inflammation/infection and bronchiectasis. Semiquantitative analysis showed a statistically significant difference between benign and malignant positive lesions on the late images, and may play a complementary role in interpretation. 99mTc-depreotide was a useful noninvasive tool in the evaluation of patients with LN, allowing for the exclusion of malignancy with great confidence, due to its high sensitivity. Because of moderate specificity, a positive test is best valued together with clinical and radiological features.

Topics: Adult; Aged; Female; Humans; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Somatostatin; Tomography, Emission-Computed, Single-Photon

To evaluate the diagnostic value of a new somatostatin analog, 99mTc-Depreotide, in differentiating benign from malignant lesions in patients with pulmonary nodules or masses.. A pilot study was performed on 28 patients referred to our Lung Department on suspicion of lung cancer. A chest X-ray, computed tomography (CT) of the thorax and upper abdomen, and scintigraphy were done--scintigraphy following the administration of 740 MBq 99mTc-Depreotide. Planar and tomographical imaging of the thorax and whole-body scanning with a gamma camera were done, and diagnostic outcome of the scintigrams was compared to CT, pathology, and clinical outcome.. Of 21 patients who had a focal high uptake of Depreotide, 17 were malignancies. One patient had two lesions with high Depreotide uptake, lung cancer, and pneumonia in the contralateral lung. Two patients with sarcoidosis and one with bilateral round atelectasis also had high Depreotide uptake bilaterally. Seven of the 8 patients with no uptake were true negative: 5 hamartomas and 2 round atelectases. One small lung cancer in the pleura sinus did not have Depreotide uptake.. The somatostatin analog Depreotide is promising for discriminating between malignant and benign lung lesions.

Topics: Adult; Aged; Aged, 80 and over; Diagnosis, Differential; Female; Humans; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Organotechnetium Compounds; Pilot Projects; Radionuclide Imaging; Receptors, Somatostatin; Somatostatin

A contrast-enhanced multidetector CT (MDCT) scan is the first choice examination when evaluating patients with suspected lung cancer. However, while the clinical focus is on CT, research focus is on molecular biological methods whereby radiolabelled pharmaceuticals are injected into participants and target malignant lung tumours. We examined whether a contrast-enhanced MDCT scan supplied with an additional non-contrast enhanced high-resolution CT scan, or a newer but more expensive (99m)Tc depreotide single photon emission CT (SPECT) scan, was the better first-choice examination for the work-up of pulmonary lesions. Furthermore, we examined whether a (99m)Tc depreotide SPECT scan was an appropriate second-choice examination for patients with indeterminate lesions.. 140 participants were included in the analysis. CT images were given a malignancy potential rating of 1, 2 or 3 with higher rating being indicative of disease. (99m)Tc depreotide SPECT images were graded either positive or negative. Histopathology and CT follow-up were used as reference standard. Sensitivity, specificity and diagnostic accuracy were calculated.. Overall sensitivity, specificity and diagnostic accuracy of CT were 97%, 30% and 84%, respectively. Overall sensitivity, specificity and diagnostic accuracy of (99m)Tc depreotide SPECT were 94%, 58% and 76%, respectively. For indeterminate lesions sensitivity, specificity and diagnostic accuracy of (99m)Tc depreotide SPECT were 71%, 68% and 69%, respectively.. Both CT and (99m)Tc depreotide SPECT made valuable contributions to the evaluation of pulmonary lesions. (99m)Tc depreotide SPECT results were not superior to CT results and did not contribute further to the diagnostic work-up. Regarding indeterminate lesions,( 99m)Tc depreotide SPECT sensitivity was too low.

Topics: Adult; Aged; Aged, 80 and over; Cohort Studies; Confidence Intervals; Contrast Media; Diagnosis, Differential; Female; Humans; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Multidetector Computed Tomography; Organotechnetium Compounds; Prospective Studies; ROC Curve; Sensitivity and Specificity; Solitary Pulmonary Nodule; Somatostatin; Tomography, Emission-Computed, Single-Photon

The affinity of various malignant neoplasms including small cell and non-small cell lung cancer for peptide analogs of somatostatin has been well documented. Depreotide is such an analog and can be complexed with technetium-99m ((99m)Tc depreotide) for optimal imaging properties. Using this radiopharmaceutical, solitary pulmonary nodules (SPN) were previously evaluated in a successful phase II/III trial. The results of the larger multicenter phase III study using (99m)Tc depreotide to differentiate malignant and benign etiologies in SPN are now presented.. Patients with SPN 30 years, and no demonstrable radiographic stability for the prior 2 years were studied. All underwent single-photon emission CT (SPECT) with (99m)Tc depreotide and subsequent tissue histologic examination. Three nuclear medicine specialists blinded to histologic findings examined the SPECT images and scored them as positive or negative based on the presence or absence of activity in the radiographic region of the SPN. The final result was determined by the majority score, which was then compared with the histologic result.. Of the 114 individuals studied, 88 had a histologic result compatible with malignant neoplasm. (99m)Tc depreotide scintigraphy correctly identified 85 of this group, with three false-negative determinations compared with histology. There were seven false-positive determinations, including six granulomas and one hamartoma. (99m)Tc depreotide scintigraphy correctly excluded malignancy in 19 of 26 patients with benign histologic findings. The sensitivity of this method was 96.6% with a specificity of 73.1%.. (99m)Tc depreotide scintigraphy is a safe and useful method for the noninvasive evaluation of SPN with a sensitivity and accuracy comparable to that reported for fluorine-18 fluorodeoxyglucose positron emission tomography.

Topics: Aged; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Contrast Media; Diagnosis, Differential; Female; Humans; Image Enhancement; Intercellular Signaling Peptides and Proteins; Lung; Lung Diseases; Lung Neoplasms; Male; Middle Aged; Peptides; Predictive Value of Tests; Prospective Studies; Solitary Pulmonary Nodule; Somatostatin; Tomography, Emission-Computed, Single-Photon

Topics: Biomarkers, Tumor; Contrast Media; Diagnosis, Differential; Humans; Intercellular Signaling Peptides and Proteins; Lung Diseases; Lung Neoplasms; Peptides; Reagent Kits, Diagnostic; Receptors, Somatostatin; Tomography, Emission-Computed; Tomography, X-Ray Computed