Maria Granowska

123I radioiodinated antibody imaging of occult ovarian cancer

A monoclonal antibody HMFG2 labeled with iodine 123 (123I) was given to a patient who had ovarian cancer. The scan taken 18 hours after administration of the antibody demonstrated the presence and the position of residual tumor in the pelvis that was not previously detected by ultrasonography and computerized tomography (CT) scanning. The presence of tumor was confirmed by surgery and histologic as well as immunoperoxidase examination of resected tissues. The tumor mass found was less than 0.8 cm in diameter. It is concluded that, in the search for residual or early ovarian cancer in the pelvis, monoclonal antibody scanning using 123I‐labeled HMFG2 can complement ultrasonography and CT scanning.

Radiolabelled monoclonal antibodies in oncology. III. Radioimmunotherapy.

The requirements, problems and progress of radioimmunotherapy in the management of certain malignancies are described. The future prospects using a two- or three-stage approach are promising.

Radiolabelled monoclonal antibodies in oncology I. Technical aspects

The principles and technique of radioimmunoscintigraphy are described with particular reference to the choice of antibody and the radiolabel, the radiolabelling procedure and the patient protocols. The arguments in favour of using a short-lived high count rate radionuclide for radioimmunoscintigraphy are set out. Methods for labelling monoclonal antibodies with 111In, 123I or 99Tcm are described. The early image at 10 min after injection is essential as it acts as a template with which later images may be compared. In conclusion, many of the technical aspects of radioimmunoscintigraphy have been overcome and it is ready for wider application in oncology patients.

Imaging of phaeochromocytoma and adrenal medulla with 123I-meta-iodobenzyl guanidine

A method for preparing meta-iodobenzyl guanidine (MIBG) labelled with 123I is described. This compound clearly imaged the normal adrenal medulla in seven out of eight patients with hypertension. The sites of metastases were demonstrated in two patients with malignant phaeochromocytoma.

Diagnostic evaluation of 111In and 99mTc radiolabelled monoclonal antibodies in ovarian and colorectal cancer: Correlations with surgery

The results of radioimmunoscintigraphy, RIS, in colorectal and gynaecological cancers were related to the surgical findings and the analysis of the surgical specimens. The improvement in the accuracy of RIS with the progression from 111In through 123I to 99mTc as radiolabel is demonstrated. The convenience, low cost and low radiation dose of 99mTc-labelled antibodies brings the technique of RIS into routine use in the management of patients with these cancers.

Cerebral blood flow in hypertensive patients with cerebrovascular disease: technique for measurement and effect of captopril.

Nineteen patients with unilateral cerebrovascular disease underwent cerebral blood flow (CBF) measurements; ten had been receiving conventional therapy and then were studied after treatment with captopril without or with a diuretic and nine on conventional therapy were studied twice as a control group. CBF (ml min-1) was measured after an intravenous injection of 99Tcm-labelled patients red cells with a computer linked gamma camera over the vertex and a probe over the aorta. With deconvolution analysis regional CBF is given by regional cerebral volume divided by regional mean transit time. Results in the captopril group showed on average a 10% fall in mean blood pressure and a 10% rise in blood flow to the affected hemisphere. In the control group there was on average a 4% fall in pressure, together with an 11% fall in CBF to the affected hemisphere. Captopril appears to maintain autoregulation in cerebrovascular disease.

Therapeutic considerations in the use of intraperitoneal radiolabelled monoclonal antibodies in ovarian carcinoma.

Eleven patients with ovarian cancer have been treated with a radiolabelled monoclonal antibody directed against human milk fat globule membrane (HMFG2). All patients had Stage III disease and had previously undergone debulking surgery followed by chemotherapy. Although 16 patients have been referred, 5 could not be treated. This paper discusses the criteria for patient selection and treatment, and describes the technical difficulties of this form of therapy and the complications sustained following the intraperitoneal instillation of up to 150 mCi iodine-131 labelled HMFG2. Significant complications included two ileo-cutaneous fistulae and peritonitis in one patient which prevented treatment from being given.

Total and Intrarenal Flow Distribution in Healthy Subjects: Technique, Acute Effects of Ibopamine and of Indoramin

A technique is described for measuring an index of cardiac output, total and individual renal plasma flow, cortical and juxtamedullary nephron flow non-invasively in man with a single injection of 123I-o-iodohippurate. Ibopamine, a dopamine analogue, was administered orally, 200 and 600 mg, in a double-blind, placebo-controlled cross-over study in 6 healthy subjects. No change in pulse, blood pressure, cardiac output, urea, creatinine or electrolytes was seen. Ibopamine reduced effective renal plasma flow and cortical nephron flow and increased urine flow significantly. This may be due to differential vasoconstrictor and vasodilator effects on the two populations of nephrons. Indoramin, and alpha-1 postsynaptic adrenoceptor blocker, was administered orally, 50 mg, in a double-blind, placebo-controlled cross-over study in 14 healthy young males. No change in pulse, cardiac output, urea, creatinine or electrolytes was seen. Indoramin significantly reduced upright but not supine blood pressure and significantly increased effective renal plasma flow. Cortical nephron flow and juxtamedullary nephron flow tended to rise. Plasma renin activity was significantly elevated although there was no change in urinary sodium output. The effect of drugs on intrarenal blood flow distribution may be relevant to the management of essential hypertension.

A multiobserver comparison of 99mTcO4 and 123I thyroid imaging.

The thyroids of forty patients were imaged using 2 mCi (74 MBq) 99mTc pertechnetate (99mTcO4) followed within one week by 2 mCi (74 MBq) 123I Iodide. The images obtained were evaluated by eight observers for 6 morphological criteria and assigned to 6 diagnostic categories with a confidence grading on a seven level scale (grade 1 being that for maximum confidence). Images were obtained with 123I for the same counts and the same times as those with 99mTcO4 and compared using an index in which the number of diagnostic categories and the mean confidence grading within each category were taken into account. The mean index obtained for 99mTcO4 images (9.2) was significantly greater (P>0.05, thus representing a lower observer confidence and less interobserver diagnostic agreement) than the mean indices for 123I equal count images (5.6) and 123I equal time images (6.8). The diagnoses made on the basis of 123I images were more frequently concordant with the final diagnosis after six months follow up (75% for equal counts and 77% for equal time) than those with 99mTcO4 (63%). The radioisotope of iodine most suited to modern nuclear medicine instrumentation and with the most favourable radiation dosimetry is 123I which is recommended for those areas of thyroid imaging where iodine is superior.

Radioimmunoscintigraphy of ovarian tumors using a new monoclonal antibody, SM-3

Radioimmunoscintigraphy with SM-3 monoclonal antibody produces results similar to those obtained with 123I-labeled HMFG-2. The tumor specificity of SM-3 in vitro is not as marked as that in vivo. SM-3 is, however, much easier to produce in tissue culture and, with the availability of 99mTc labelling, has allowed radioimmunoscintigraphy to be done as an outpatient procedure. This technique has important implications for the continuing management of patients with ovarian cancer.