Use of the radiolabeled murine monoclonal antibody, 111In-CYT-103, in the management of colon cancer.

Monoclonal antibodies directed at tumor-associated antigens may be useful adjuncts for the management of patients with colorectal cancer. The murine monoclonal antibody, B72.3, binds Tag-72, a cell-surface antigen, which is expressed by colorectal carcinoma cells. We investigated the benefit of indium-111-labeled B72.3, 111In-CYT-103, in localizing the presence and extent of disease in patients with suspected or biopsy-proven primary colorectal cancer and in patients with apparently localized recurrent colorectal adenocarcinoma. Twenty patients were enrolled in this study. Each patient received 1 mg of B72.3 labeled with 4 to 5 mCi of 111In. Patients then underwent planar and single-photon emission computed tomographic imaging 2 to 5 days after infusion. Fifteen patients underwent surgery 1 to 14 days after scanning. There were 11 true positives, 1 false positive, 2 true negatives, and 1 false negative. The 111In-CYT-103 scan correctly identified the presence or absence of tumor in the 15 patients in whom biopsies were obtained, for an accuracy rate of 87%. Overall, 111In-CYT-103 supplied clinically useful information regarding the extent of disease that was not previously reported by standard techniques in 33% (5 of 15) of patients who underwent surgical exploration. We conclude that 111In-CYT-103 is a promising imaging agent for patients with potentially resectable recurrences and for those patients with a presumed isolated primary tumor requiring preoperative staging.

Computer-assisted sequential quantitative analysis of gallium scans in pulmonary sarcoidosis.

Fifty-one sequential gallium citrate scans were performed in 22 patients with biopsy-proven sarcoidosis. A computer-assisted quantitative analysis of these scans was performed to obtain a gallium score. The changes in gallium score were correlated with changes in serum angiotensin converting enzyme (SACE) activity and objective changes in clinical status. There was a good concordance between changes in gallium score, SACE activity and clinical assessment in patients with sarcoidosis, and changes in gallium index were slightly superior to SACE index in assessing activity of sarcoidosis.

A comparison of computed tomography and radionuclide scanning for detection of brain metastases in small cell lung cancer.

Neurologic history and examination, radionuclide brain scans (RN), and computed tomographic brain scans (CT) were performed at diagnosis and sequentially in 153 consecutive patients with small cell lung cancer (SCLC) to assess the sensitivity and accuracy of these screening methods and to determine whether the early detection of brain metastases influences survival. CT scans (sensitivity, 98%; positive predictive accuracy, 98%) were superior to RN scans (sensitivity, 71%; positive predictive accuracy, 86%) in patients with or without neurologic signs or symptoms. However, CT scans were positive in only 6% of asymptomatic patients at diagnosis and 13% of asymptomatic patients after systemic therapy. Brain metastases detected by CT scan were the sole site of extensive-stage disease in 6% of patients at diagnosis. Despite the enhanced ability of CT scans to detect asymptomatic lesions, survival after therapeutic cranial irradiation was similar for asymptomatic and symptomatic patients. The results suggest that CT brain scans should be used routinely in SCLC patients with neurologic signs or symptoms, at diagnosis (when treatment decisions are based on stage), and at six-month intervals in patients with prior brain metastases and in whom erratic follow-up is likely.

Diagnosis and significance of liver metastases in small cell carcinoma of the lung.

One hundred fifty-seven consecutive patients with small cell lung cancer seen at the National Cancer Institute over a four-year period underwent a series of pretherapy liver staging procedures to determine optimal means of detection and prognostic implications of hepatic metastases. Liver evaluation included physical examination, liver function tests, and liver scan (radionuclide or computerized tomography [CT]), as well as percutaneous and/or peritoneoscopy-directed liver biopsy when possible (74%). Liver metastases were detected in 26% of patients. Peritoneoscopy was the most sensitive method of liver evaluation and increased the detection of liver metastases when done in a sequential fashion after percutaneous liver biopsy from 18 to a total of 27 patients. Of the noninvasive procedures, radionuclide and CT liver scan were the most accurate concurring with liver biopsy in 87% of patients but permitting correct discrimination of stage in excess of 96% of patients. The accuracy of this noninvasive procedure was enhanced by an algorithm combining the results of radionuclide liver scan with liver function tests to detect patients with high or low likelihood of liver involvement. The survival and response of patients with liver metastases was significantly worse than those without such metastases with no three-year disease-free survivors among patients with liver metastases.

Comparative value of bone scintigraphy and radiography in monitoring tumor response in systemically treated prostatic carcinoma.

Radionuclide bone scans and skeletal radiographs were obtained before and during combination chemotherapy or initial hormonal treatment in 46 patients with disseminated adenocarcinoma of the prostate. The purpose of the study was to determine the usefulness of these two modalities in evaluating tumor response to therapy. Prior to treatment, bone scans were positive in 44 patients (96%). In all but one patient either bone radiographs or bone marrow biopsy revealed evidence of osseous metastases. In 22 patients partial response to therapy was documented by a variety of other staging tests. Eleven of these patients showed concurrent or later improvement on bone scans; one showed improvement on a radiograph. "Flare phenomena" were observed relatively frequently since 23% of the scans and 50% of the radiographs showed worsening at the time of response. Bone scans revealed worsening in 79% of 33 patients with disease progression of extraosseous tumor; radiographs were equally sensitive (82% worsening). It is concluded that bone scans in particular are useful for monitoring tumor status in systemically treated patients with prostate cancer. However, because of the lack of sensitivity for response and paradoxical worsening with tumor regression in some patients, scans are not accurate enough to be employed as the sole test in following these patients.

Treatment of frequent ventricular arrhythmia with encainide: assessment using serial ambulatory electrocardiograms, intracardiac electrophysiologic studies, treadmill exercise tests, and radionuclide cineangiographic studies.

The effects of encainide on ventricular arrhythmia and left ventricular function were studied in 21 patients with chronic, high-grade ventricular arrhythmia using a prospective, 3-month, placebo-controlled, single-blind trial design. Encainide caused a 96% decrease in the average hourly frequency of ventricular premature complexes (VPCs) and comparable reductions in salvos of nonsustained ventricular tachycardia (VT) and episodes of sustained VT. Intracardiac electrophysiologic testing showed prolonged intraatrial and intraventricular conduction times and increased atrial, atrioventricular nodal, and ventricular refractory periods with both i.v. and oral encainide without His-Purkinje block, despite marked prolongation of HV and QRS intervals. Induced repetitive ventricular beating after ventricular extrastimuli in 15 patients showed persistent repetitive ventricular beating with chronic oral encainide in seven patients, four of whom had sustained VT within 2 months of treatment on encainide. Encainide did not reduce exercise capacity or left ventricular ejection fraction at rest or during supine exercise. Minor adverse effects of encainide in 11 of 21 patients included dose-related visual disturbances, dizziness and sinus pauses (less than 3 seconds). Major adverse effects included the new appearance of sustained VT in three of 20 patients (15%). Oral encainide effectively reduces the frequency and grade of VPCs, prolongs intracardiac conduction times, and does not impair left ventricular performance. However, it is associated with frequent minor side effects and uncommon but potentially severe major side effects (sustained VT), both of which apparently have a direct relationship to the size of the dose.

Acebutolol and left ventricular function: assessment by radionuclide angiography.

We assessed the effects of acebutolol, a cardioselective beta blocker, on global and regional left ventricular function in 26 patients with chronic angina pectoris. All patients underwent rest and maximal supine bicycle exercise radionuclide angiography while on placebo and oral acebutolol (400 mg three times a day). Resting ejection fraction on placebo was 51 +/- 3% and on acebutolol was 54 +/- 3% (p less than 0.05). No resting ejection fraction decreased greater than or equal to 7%. Only one patient (resting ejection fraction 28% on placebo and 21% on acebutolol) developed signs of fluid retention. Exercise nuclear studies on placebo revealed responses consistent with coronary artery disease (abnormal ejection fraction response to exercise and regional wall motion abnormalities) in 24 of 26 patients. Peak exercise ejection fraction was of the same order on placebo and acebutolol (51 +/- 3% and 54 +/- 3%, p = NS). In four patients the ejection fraction response to exercise became normal and in five patients all regional wall motion abnormalities became normal on acebutolol. Cardioselective beta blockade with acebutolol in effective antianginal doses is safe and may improve resting and exercise ventricular function.

Computed tomography in primary hepatocellular carcinoma.

Abdominal computed tomography was performed on seven patients with primary hepatocellular carcinoma. The liver appeared normal in one patient, while in the other six patients the tumor was identified as an area of decreased attenuation. In four cases, the tumor was seen better following intravenous administration of a contrast agent, and, in two of these cases, it was not seen on the precontrast scans. In only one case was the hepatoma better seen on the precontrast examination, and it could still be identified following contrast enhancement. Hepatomegaly and an irregular hepatic contour were other findings in these patients.

Noninvasive diagnosis of left ventricular pseudoaneurysm: role of two dimensional echocardiography and radionuclide gated pool imaging.

This report describes a case of left ventricular pseudoaneurysm diagnosed with two dimensional real time echocardiography. The two dimensional echocardiogram identified not only the pseudoaneurysmal sac but also the site of left ventricular rupture. When supplemented with radioisotope gated cardiac blood pool scanning, the noninvasive studies demonstrated combined true and false left ventricular aneurysms. Left ventricular pseudoaneurysm can be diagnosed using two dimensional echocardiography and nuclear imaging, permitting early operative intervention before fatal rupture.