PubMed Health⌕ Search

Biomedical subjects

D A Podoloff

Publications and source records attributed to D A Podoloff.

69 records · Page 4Linked to original sources
PubMed1992

SPECT in the evaluation of cancer patients: not quo vadis; rather, ibi fere summus.

In the past 7 years, single photon emission computed tomography (SPECT) has evolved from an interesting nuclear medicine technique rarely performed because of technical difficulties into a valuable clinical tool in the management of cancer cases. The development of stable multidetector instruments with collimators and gantries specifically designed for SPECT and the introduction of new radiopharmaceuticals recently approved by the U.S. Food and Drug Administration have rapidly moved SPECT from the field of clinical investigation to clinical practice. SPECT is a valuable addition to other tomographic modalities capable of displaying the physiology of disease as well as anatomy. In this work the authors describe the role of SPECT in a cancer center and, in particular, how they use it to solve clinical problems. They also review the published literature, when appropriate. The authors have found SPECT of particular value in evaluation of myocardial ischemia, in differentiating tumor recurrence from posttherapy changes in the lymphomas, in tumor diagnosis and surveillance, and in separating hemangioma from malignant lesions in the liver.

Abdomen↗
PubMed1991

Indium-111-labeled B72.3 monoclonal antibody in the detection and staging of breast cancer: a phase I study.

Sixteen patients with primary breast cancer were studied with a pancarcinoma monoclonal antibody B72.3, an IgG1 molecule directed against tumor-associated glycoprotein (TAG-72) present in several tumors. Five millicuries of 111In was used to label 0.2 mg (six patients), or 2 mg (six patients), or 20 mg using the site-directed bifunctional DTPA method (at carbohydrate moiety). Digital, planar, and SPECT images were obtained at 2, 48, 72 and 96 hr when possible. HAMA levels were obtained before the Mab infusion and at 1, 3, and 6 wk postinfusion. Fourteen of 14 known primary breast lesions were detected by imaging (100% sensitivity). Two fibrocystic lesions were negative. Seven of 14 patients had lymph node metastases by histologic methods, but all were missed by radioimmunoscintigraphy. Tumor uptake of Mab ranged 0.00054%-0.0038% of the ID/g. The tumor-to-normal breast tissue ratio was 4.3 +/- 0.91 (mean +/- s.e.m.). Lymph nodes localization of 111In-B72.3 by tissue analysis was similar for tumor-bearing and normal nodes (0.0039 +/- 0.0023 versus 0.0025 +/- 0.0019). Pharmacokinetics revealed mean plasma half-life of 33.3-41.2 hr for the different doses. There was no statistical difference between any of the pharmacokinetic parameters of different doses. HAMA was positive only in 17% of the patients. The study suggests that this antibody has 100% sensitivity for primary breast cancers, but very poor detection rate of metastatic lesions in axillary lymph nodes; thus making it of questionable value in the initial staging process of this disease.

Antibodies, Monoclonal↗
PubMed1990

Quality assurance in a nuclear medicine department.

This article reviews the general principles of quality assurance (QA) in an imaging department, with emphasis on nuclear medicine. The various steps taken during the development of the QA program reflect the response of the QA committee as it came to a better understanding of the components of QA. Accrediting and regulatory bodies have had important roles in providing guidance. Quality control of instrumentation and radiopharmaceuticals opened the gateway to monitoring in high-volume, high-risk areas; however, QA expanded this concept into better generic and clinical monitoring. Encouragement of the use of quality of care referral forms resulted in greater participation by all members of the department. Examples of physicians' QA activities include double reading of images and sending of code cards. Experience with other forms of physician QA activities is also included. The QA committee provides a forum for five steps of QA: identify problems, assess the causes, implement action to prevent them, monitor effects of the actions, and document these activities. These steps should lead to improvement in the standards of patient care.

Cancer Care Facilities↗
PubMed1989

Pitfalls in multimodality imaging in a patient undergoing evaluation for bone marrow transplantation.

Autologous bone marrow transplantation is being offered with increasing frequency as a therapeutic alternative to patients who have failed conventional chemotherapy. Presently, these patients are being evaluated with a variety of imaging modalities, including planar radiographs, nuclear bone and bone marrow scans, and CT and magnetic resonance imaging. A case is presented here that demonstrates potential pitfalls encountered in this multimodality approach. Correlation of imaging findings with patients history and clinical findings is essential for optimal interpretation of functional imaging modalities.

Adult↗
PubMed1989

"Sub"-super scan--manifestation of bone marrow metastases?

A case is presented in which bone imaging over a period of 1 year indicated continued and increased radionuclide uptake. In association with CT and magnetic resonance imaging studies it was determined that the continued increased activity was related to developing bone marrow metastases.

Adult↗
PubMed1989

Radionuclide imaging in the evaluation of osteomyelitis and septic arthritis.

Despite controversy over its exact role, radionuclide imaging plays an important role in the evaluation of patients suspected of having osteomyelitis. The differentiation between osteomyelitis and cellulitis is best accomplished by using a three-phase technique using Tc-99m methylene diphosphonate (MDP). Frequently, it is necessary to obtain multiple projections and magnification views to adequately assess suspected areas. It is recommended that a Ga-67 or In-111 leukocyte scan be performed in those cases where osteomyelitis is strongly suspected clinically and the routine bone scan is equivocal or normal. Repeated bone scan after 48 to 72 h may demonstrate increased radioactivity in the case of early osteomyelitis with the initial photon-deficient lesion. In-111 leukocyte imaging is useful for the evaluation of suspected osteomyelitis complicating recent fracture or operation, but must be used in conjunction with clinical and radiographic correlation. The recognition of certain imaging patterns appears helpful to separate osteomyelitis from septic arthritis or cellulitis.

Adult↗
PubMed1988

Enhanced detectability of local colloid uptake with SPECT imaging.

Focal "hot" spots with Tc-99m sulfur colloid in the left lobe of the liver have been reported in a variety of conditions. SPECT imaging of the liver has demonstrated increased accuracy of detecting small sized hemangiomas. A case is presented in which the SPECT images clearly demonstrate a "hot" spot in the left lobe of the liver that is not well demonstrated on planar imaging. There is little information regarding the enhanced detectability of left lobe "hot" spots with SPECT imaging. This case demonstrates such findings.

Adult↗
PubMed1975

67Gallium in 68 consecutive infection searches.

When employed in the study of peripheral infections, 67Ga scanning is sensitive and accurate. When used as a diagnostic tool for suspected abdominal abscesses, it locates and delineates abscesses in somewhat over half the cases. Moreover, the true-negative rate is high and the false-positive rate is acceptably low. Gallium scans should be interpreted with all available clinical information. The coexistence of noeplasm is a problem which at present is not completely resolved.

Abscess↗
PubMedDate not supplied

Preliminary study of cardiac accumulation of F-18 fluorotamoxifen in patients with breast cancer.

The clinical meaning of cardiac uptake of [18F]fluorotamoxifen was assessed. Tamoxifen, a nonsteroidal antiestrogenic drug for treatment and prevention of breast cancer, has a cardioprotective, estrogen-like effect in postmenopausal women. We conducted a pilot study of [18F]fluorotamoxifen to evaluate its clinical usefulness in patients with breast cancer. Significant cardiac uptake of [18F]fluorotamoxifen in five patients was found in the pilot study. We performed positron emission tomography (PET) with [18F]fluorotamoxifen. The intracardiac distribution of [18F]fluorotamoxifen was observed and compared with the patients' clinical symptoms, past history, and results of the electrocardiogram (ECG). None of the patients had a prior history of ischemic heart disease. Various patterns of [18F]fluorotamoxifen distribution were seen in the heart: one patient showed homogeneous distribution; two had defects in the lateral wall; one had patchy distribution; and in one the uptake was questionable. Non-uniform cardiac uptake may be related to myocardial damage. Cardiac uptake of tamoxifen suggests that its cardioprotective benefits may be related not only to serum cholesterol reduction but also to a direct cardioprotective action. Further experimental studies are required to elucidate the pathophysiological mechanism of cardiac uptake of [18F]fluorotamoxifen.

Adult↗
PubMedDate not supplied

Biodistribution and dosimetry results from a phase III prospectively randomized controlled trial of Zevalin radioimmunotherapy for low-grade, follicular, or transformed B-cell non-Hodgkin's lymphoma.

UNLABELLED: Radiation dosimetry studies were performed in patients with non-Hodgkin's lymphoma (NHL) treated with 90Y Zevalin (90yttrium ibritumomab tiuxetan, IDEC-Y2B8) on a Phase III open-label prospectively randomized multicenter trial. The trial was designed to evaluate the efficacy and safety of 90Y Zevalin radioimmunotherapy compared to rituximab (Rituxan, MabThera) immunotherapy for patients with relapsed or refractory low-grade, follicular, or transformed NHL. An important secondary objective was to determine if radiation dosimetry prior to 90Y Zevalin administration is required for safe treatment in this patient population. METHODS: Patients randomized into the Zevalin arm were given a tracer dose of 5 mCi (185 MBq) (111)In Zevalin (111indium ibritumomab tiuxetan) on Day 0, evaluated with dosimetry, and then administered a therapeutic dose of 0.4 mCi/kg (15 MBq/kg) 90Y Zevalin on Day 7. Both Zevalin doses were preceded by an infusion of 250 mg/m(2) rituximab to clear peripheral B-cells and improve Zevalin biodistribution. Following administration of (111)In Zevalin, serial anterior and posterior whole-body scans were acquired and blood samples were obtained. Residence times for 90Y were estimated for major organs, and the MIRDOSE3 computer software program was used to calculate organ-specific and total body radiation absorbed dose. Patients randomized into the rituximab arm received a standard course of rituximab immunotherapy (375 mg/m(2) weekly x 4). RESULTS: In a prospectively defined 90 patient interim analysis, the overall response rate was 80% for Zevalin vs. 44% for rituximab. For all patients with Zevalin dosimetry data (N=72), radiation absorbed doses were estimated to be below the protocol-defined upper limits of 300 cGy to red marrow and 2000 cGy to normal organs. The median estimated radiation absorbed doses were 71 cGy to red marrow (range: 18-221 cGy), 216 cGy to lungs (94-457 cGy), 532 cGy to liver (range: 234-1856 cGy), 848 cGy to spleen (range: 76-1902 cGy), 15 cGy to kidneys (0.27-76 cGy) and 1484 cGy to tumor (range: 61-24274 cGy). Toxicity was primarily hematologic, transient, and reversible. The severity of hematologic nadir did not correlate with estimates of effective half-life (half-life) or residence time of 90Y in blood, or radiation absorbed dose to the red marrow or total body. CONCLUSION: 90Y Zevalin administered to NHL patients at non-myeloablative maximum tolerated doses delivers acceptable radiation absorbed doses to uninvolved organs. Lack of correlation between dosimetric or pharmacokinetic parameters and the severity of hematologic nadir suggest that hematologic toxicity is more dependent on bone marrow reserve in this heavily pre-treated population. Based on these findings, it is safe to administer 90Y Zevalin in this defined patient population without pre-treatment (111)In-based radiation dosimetry.

Antibodies, Monoclonal↗