sodium-pertechnetate-tc-99m and Carcinoma--Small-Cell

A new pentadecapeptide bombesin analogue was prepared by Fmoc synthesis, purified by HPLC and identified by electron ionization mass spectrometry. The biological activity of the new peptide was tested on isolated human colonic muscle cells and compared to native bombesin. Labelling of the new biomolecule with Tc-99m yielded a single radioactive species which remained stable at room temperature for eight hours. In a binding assay, the radiolabelled peptide showed high affinity for oat-cell carcinoma (Kd = 9.8 nM) and colorectal adenocarcinoma (Kd = 27.2 nM). Biodistribution studies, performed in normal rodents, indicated uptake by organs that normally express bombesin receptors, such as liver, intestines and kidneys. Scintigraphic studies, performed in nude mice transplanted with small cell lung carcinoma and colon cancer cells, showed significant tumor uptake two hours p.i. The new synthetic pentadecapeptide appears to have promise for several malignancies, including oat-cell lung carcinoma, colorectal cancer and gastroenteropancreatic (GEP) tumors.

Topics: Animals; Bombesin; Carcinoma, Small Cell; Colonic Neoplasms; Female; Humans; Isotope Labeling; Lung Neoplasms; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Peptides; Radionuclide Imaging; Rats; Rats, Wistar; Receptors, Bombesin; Sodium Pertechnetate Tc 99m; Tissue Distribution; Tumor Cells, Cultured

A man with small-cell carcinoma of the lung underwent a Tc-99m red blood cell gastrointestinal bleeding study because he had a tarry stool. In his first-pass study, there was early filling of the radiotracer in the middle and lower portion of the inferior cava; in addition, the study revealed a distorted and distended inferior vena cava along with an abdominal aortic aneurysm. Collateral circulation of the trunk was noted in the subsequent bloodpool images. A subsequent radionuclide superior vena cava study confirmed superior vena cava obstruction just above the entrance to the right atrium. Contrast-enhanced computed tomographic scans of the chest showed that the superior vena cava was compressed completely by the mediastinal tumor mass and that collateral circulation was present. Development of collateral circulation after superior vena cava obstruction in this patient allowed venous blood to return to the right atrium through the inferior vena cava. Thus, early filling of the inferior vena cava on radionuclide first-pass studies of the abdomen may serve as a sign of superior vena cava obstruction.

Topics: Adult; Carcinoma, Small Cell; Collateral Circulation; Coronary Artery Bypass; Erythrocytes; Humans; Lung Neoplasms; Male; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Superior Vena Cava Syndrome; Tomography, X-Ray Computed; Vena Cava, Inferior

In 30 patients with lung cancer undergoing non-surgical treatment, we performed perfusion lung imaging using 99mTc-MAA and inhalation lung studies using Technegas before and after treatment and evaluated regional perfusion and ventilation status in the lung regions where bronchogenic carcinoma was located. Regional ventilation status was preserved rather than perfusion counterpart (V > P) in 18 patients (18/30 = 60.0%) before treatment, while the former was better than the latter in 27 patients (27/30 = 90.0%) after treatment, indicating that regional ventilation status improved more significantly than regional perfusion counterpart after treatment (p = 0.005). We also classified the therapeutic effect for regional perfusion and ventilation status as improved, unchanged, or worsened, respectively; improvement in regional perfusion status was observed in 17 patients (56.7%) and that in regional ventilation status in 24 patients (80.0%). There was a statistically significant correlation between improved regional perfusion and ventilation status (p = 0.0018) when therapeutic effect was recognized. The patients who showed improvement in regional perfusion status after treatment always showed improved regional ventilation status, but 7 patients showed either unchanged or worsened regional perfusion status after treatment, although regional ventilation status was improved. In conclusion the pulmonary vascular beds seem more vulnerable to bronchogenic carcinoma and improvement in regional perfusion status was revealed to be more difficult than that in regional ventilation status after treatment.

Topics: Adult; Aged; Carcinoma, Small Cell; Carcinoma, Squamous Cell; Female; Humans; Lung; Lung Neoplasms; Male; Middle Aged; Outcome and Process Assessment, Health Care; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Technetium Tc 99m Aggregated Albumin; Treatment Outcome; Ventilation-Perfusion Ratio

Doxorubicin is cardiotoxic and its use must be monitored carefully. Incidence of refractory cardiac failure is shown to increase once the cumulative dose exceeds 450 mg/m2. However, significant decline of ejection fraction (EF) may occur even at lower dose levels. EF was monitored using Multigated Radionuclide Angiography (MUGA) scan of all consecutive lung cancer patients, treated with Doxorubicin based regimens. Thirteen of 82 patients showed a significant (more than 15%) decline of left ventricular EF. The dose of doxorubicin producing this decline ranged between 91-180 mg/m2. Actual decline in EF ranged between 16-45%. Only 5 of 13 patients developed symptoms attributable to the cardiac disease. Doxorubicin can alter EF significantly in lung cancer patients at levels well below which are considered 'safe'. The reason for massive decline in ejection fraction in these patients has been hypothesized.

Topics: Aged; Antibiotics, Antineoplastic; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cardiac Output, Low; Doxorubicin; Female; Follow-Up Studies; Humans; Lung Neoplasms; Male; Middle Aged; Radionuclide Angiography; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Stroke Volume; Ventricular Function, Left

Topics: Aged; Carcinoma, Small Cell; Diagnosis, Differential; Humans; Lung Neoplasms; Male; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Vena Cava, Superior