Frank H. DeLand

Use of radiolabeled antibodies to carcinoembryonic antigen for the detection and localization of diverse cancers by external photoscanning

To determine whether tumors containing carcinoembryonic antigen could be detected by administration of a radiolabeled, affinity-purified, goat lgG having 70 per cent immunoreactivity against carcinoembryonic antigen, 18 patients with a history of cancer of diverse histopathology received an average total dose of 1.0 mCi of 131l-labeled lgG. Total-body photoscans were performed with a gamma scintillation camera at various intervals after administration of the radioactive antibody. Ordinary photoscans proved difficult to interpret because of blood-pool background radioactivity, thus necessitating the computer subtraction of radioactive blood-pool agents from the antibodys 131l activity. Tumor location could be demonstrated at 48 hours after injection in almost all cases studied. The scans were negative in patients without demonstrable tumors or with tumors apparently devoid of carcinoembryonic antigen. Circulating antigen levels of up to 350 ng per milliliter did not prevent successful tumor imaging after injection of the radioantibody.

Diagnosis of Pulmonary Embolism. A Correlative Study of the Clinical, Scan, and Angiographic Findings

Seventy-one patients with suspected pulmonary embolism had both pulmonary scans and angiograms. Clinically it was impossible to predict the absence or presence of subsequent angiographic evidence of pulmonary embolism in the individual patient. In 24 patients the scans showed defects that were believed to indicate a high probability of pulmonary embolism—namely, perfusion defects that corresponded to specific anatomical segments of the lung together with normal chest radiographs or radiographs suggestive of pulmonary embolism. Specific angiographic evidence of pulmonary embolism was found in 18 (75%) of these patients. Diffuse, patchy, and non-segmental perfusion defects were seen in 28 patients. Only seven (25%) of this group had angiographic abnormalities specific for embolism. In 12 patients with normal lung scans none showed subsequent evidence of embolism by angiography. It is concluded firstly that lung scanning is a sensitive screening procedure for pulmonary embolism and, secondly, that segmental perfusion defects are highly suggestive of pulmonary embolism.

Disposition of radiolabelled suppositories in humans

The disposition of Witepsol H 15 suppositories radiolabelled with [99m Tc] technetium hydroxymethyldiphosphonate was studied after rectal administration in volunteers. The migration of the radiolabel was monitored continuously by external scintigraphy. The resulting scintiphotos were superimposed on lower GI radiographs to determine the extent of spreading of the dosage form in the rectum. The dosage form migrated approximately 5−7 cm into the rectum in nearly all of the studies and was, in general, confined to the lower and middle regions of the rectum. Since the venous supply to the lower rectum leads primarily to the inferior vena cava, the data presented here indicate that the metabolism of drugs sensitive to the ‘first‐pass’ effect may be partially avoided by their rectal administration.

Normal spleen size.

Abstract Normal spleen weight appears to be related to the age and sex of the patient. Spleen weight decreases from twenty to twenty-nine years of age and above sixty years of age but is relatively constant from thirty to fifty-nine years of age. Spleen weight is less in females than in males for all ages.

Diagnosis and treatment of neoplasms with radionuclide-labeled antibodies

The in vivo use of radionuclide-labeled antibodies to several types of tumor-associated antigens or products has proven to be a reliable method for defining primary, recurrent, metastatic, and occult carcinoma. Specificity for the radioimmunodetection procedure is high; however, the sensitivity varies depending on the size and site of the lesions. The relative roles of polyclonal- and monoclonal-type antibodies are still to be defined, since at this stage of development little difference can be demonstrated in the detection of tumor with either one. The introduction of emission computed tomography should simplify the imaging techniques appreciably and improve the resolution between nontarget and target radioactivity. Satisfactory radionuclide labels with photon energies more compatible with current imaging equipment will enhance resolution and sensitivity.

Early Detection of Bacterial Growth, with Carbon-14-Labeled Glucose

A mmimum of one day is usually required to determine the presence of bacterial growth in blood cultures. We have developed a method for the detection of bacterial growth in blood cultures that is fast, objective, and sensitive. It is based on the incubation of the cultures in liquid media to which 14C-glucose has been added as the sole source of carbohydrate. The evolution of HC-dioxide is measured as an index of bacterial growth. Method 14C02 released by the bacterial metabolism of HC-labeled glucose is measured continuously with a commercially available monitor for radioactive gas. An air pump flushes the ionization chamber of this instrument at a rate of 9.5 liters per minute. The reaction flask is connected by means of Tygon tubing to form a closed system (Fig. 1). To record the radioactivity in the perfused gas, an analogue recorder is connected to the ionization chamber. The lower limit of sensitivity of this instrument is 0.0036 µCi of 14C (1). The culture medium was 20 ml of glucose-free thioglych...

A New Radiopharmaceutical for Cisternogrgphy: Chelated Ytterbium 16911

169Yb-DTPA, which has been employed for brain and renal studies, has now been used safely for cisternography in over 30 patients referred for investigation of hydrocephalus or rhinorrhea. It is physiologically stable and diffuses into the blood from the cerebrospinal fluid. Its biological half-life in the CSF compartment is about ten hours, long enough for cisternography but short enough to keep the radiation dose low, even with millicurie doses. The radionuc1ides long physical half-life, together with the stability of its complex, permits strict quality control.

Role of liver scanning in the preoperative evaluation of patients with cancer

Liver scan characteristics and liver function tests of 72 patients with proved hepatic malignancy (54 metastatic, 18 primary) were evaluated. Well-defined focal defects were observed in 83% of patients with metastatic and 77% of patients with primary liver carcinoma. In 10% of the patients with metastatic liver disease the distribution of radioactivity was normal. Four or more biochemical liver function tests were normal in 33% of metastatic and 29% of primary liver cancer patients. Hepatic enlargement was present in the scan in 94% of the patients with liver metastases; however, data obtained from 104 necropsies of patients with hepatic metastases showed that only 46% had hepatomegaly. We recommend, therefore, that a liver scan should be performed before major tumour surgery in every patient with known malignancy regardless of normal liver size or normal liver function tests.

Radioimmunodetection of colorectal cancer

This study examines the accuracy of colorectal cancer radioimmunodetection. Twenty‐seven patients with a history of histologically‐confirmed colonic or rectal carcinoma received a high‐titer, purified goat anti‐CEA IgG labelled with 131‐I at a total dose of at least 1.0 μCi. Various body views were scanned at 24 and 48 hours after administration of the radioantibody. Three additional cases were evaluated; one had a villous adenoma in the rectum and received the 131‐I‐labelled anti‐CEA IgG, while two colonic carcinoma patients received normal goat IgG labelled with 131‐I. All of the 7 cases with primary colorectal cancer showed true‐positive tumor localization, while 20 of 25 sites of metastatic colorectal cancer detected by immune scintigraphy were corroborated by other detection measures. The sensitivity of the radioimmunodetection of colorectal cancers (primary and metastatic) was found to be 90% (true‐positive rate), the putative specificity (true‐negative rate) was 94%, and the apparent overall accuracy of the technique was 93%. Neither the case of a villous adenoma receiving the anti‐CEA IgG nor the two cases of colonic cancer receiving normal goat IgG showed tumor radiolocalization. Very high circulating CEA titers did not appear to hinder successful tumor radiolocalization. These findings suggest that in colorectal cancers the method of CEA radioimmunodetection may be of value in preoperatively determining the location and extent of disease, in assessing possible recurrence or spread postoperatively, and in localizing the source of CEA production in patients with rising or elevated CEA titers. An ancilliary benefit could be a more tumor‐specific detection test for confirming the findings of other, more conventional diagnostic measures.

Brain Scanning as a Diagnostic Aid in the Detection of Eighth Nerve Tumors

PROGRESSIVE unilateral nerve deafness is not common but requires early diagnosis for optimum treatment because it is usually caused by a neoplasm of the eighth cranial nerve. Such a tumor may not only produce irreversible damage to the acoustic nerve but may also damage other cranial nerves. We have found that brain scanning is a useful procedure in the detection of eighth nerve tumors. Materials Between 1964 and 1967 a total of 12 acoustic neuromas and 3 meningiomas involving the eighth nerve were surgically removed from 15 patients at the Johns Hopkins Hospital. Anterior, posterior, and both lateral brain scans were performed in 14 instances after the administration of 99mTc-pertechnetate. The only exception was a patient with a meningioma. Results TABLE I summarizes the results of several diagnostic studies in these patients. The lesion was diagnosed prior to surgery on the basis of the brain scan in 86 per cent of the cases. Retrograde brachial arteriography was positive or suggestive in 4 of 12 cases...