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Hossein Jadvar

Publications and source records attributed to Hossein Jadvar.

15 recordsLinked to original sources
PubMed2005

PET in pediatric diseases.

FDG-PET is being increasingly applied to pediatric conditions, particularly in oncology. PET and PET/CT scanning in children are not currently supported by Centers for Medicare and Medicaid Services unless the disease condition coincides with a reimbursed adult condition. The recent merger of the Children's Cancer Group and the Pediatric Oncology Group to form the Children's Oncology Group creates an opportunity to examine the use of FDG-PET in the management of childhood tumors in multi-institutional, cooperative efforts. The interest in incorporating PET imaging technology in pediatric medicine has been evidenced by several recent review articles summarizing the ongoing progress in this area. Future data will show that FDG-PET provides useful diagnostic information and can play a pivotal role in the clinical management and care of children with disease.

Child↗
PubMed2005

FDG PET-CT demonstration of Sjogren's sialoadenitis.

We report the positron emission tomography-computed axial tomography (PET-CT) appearance of the inflammatory involvement of the salivary glands of a 69-year-old female with a history of lymphoma and known primary Sjogren's syndrome. Hybrid PET-CT was performed 5 months after completion of chemotherapy using a Siemens Biograph scanner (Knoxville, TN) 45 minutes after intravenous administration of 15 mCi of F-18 fluorodeoxyglucose (FDG). CT transmission scan was obtained for attenuation correction. PET-CT demonstrated no evidence of hypermetabolic nodal disease but showed symmetric intensely hypermetabolic submandibular and parotid salivary glands.

Aged↗
PubMed2004

Musculoskeletal system.

Diagnostic imaging has played a major role in the evaluation of patients with cancers of the bone and soft tissue. The imaging modalities have included radiography, computed tomography, magnetic resonance imaging, and bone scintigraphy. Current experience suggests that functional imaging with positron emission tomography (PET) and [F-18]fluorodeoxyglucose (FDG) may also have an important role in the imaging evaluation of patients with bone and soft tissue sarcoma, including guiding biopsy, detecting local recurrence in amputation stumps, detecting metastatic disease, predicting and monitoring response to therapy, and assessing for prognosis. Prospective studies with large patient groups will be essential to define the exact diagnostic role of FDG PET in this clinical setting, which should also include an evaluation of the cost-effectiveness and the short-term and long-term benefits in clinical decision making and management. In this article, we review the diagnostic utility of dedicated PET and PET combined with computed tomography imaging system in the evaluation of patients with bone and soft tissue malignancies.

Bone Neoplasms↗
PubMed2004

The reproductive tract.

Diagnostic imaging has played a major role in the evaluation of patients with the cancers of the reproductive tract. The imaging modalities have included ultrasonography, computed tomography, magnetic resonance imaging, hysterosalpingography, and scintigraphy with radiolabeled monoclonal antibodies. Positron emission tomography (PET) with [F-18]fluorodeoxyglucose also has been shown to be useful in the imaging evaluation of these patients. Clinical applications have included initial staging and posttherapy restaging of disease, detecting metastatic disease, differentiating posttherapy anatomic alterations from recurrent or residual disease, and predicting and evaluating treatment response. In this article, we review the diagnostic utility of dedicated PET and combined PET-computed tomography systems in the imaging assessment of reproductive tract malignancies (excluding prostate cancer) in both sexes with an emphasis on fluorodeoxyglucose applications.

Clinical Trials as Topic↗
PubMed2002

Diagnostic utility of FDG PET in multiple myeloma.

OBJECTIVE: Very little information is available regarding the diagnostic utility of positron emission tomography with [(18)F]fluorodeoxyglucose (FDG PET) in multiple myeloma. Our objective was to further define the role of FDG PET in the clinical assessment of patients with multiple myeloma. DESIGN AND PATIENTS: Nine whole-body PET scans (45 min after intravenous administration of 370-555 MBq FDG) were performed in six patients (age 38-62 years, 5 males) with multiple myeloma for evaluation of the extent of disease at the time of initial diagnosis (n=3) and for assessment of therapy response (n=3). Three patients had PET scans both before and after therapy. Prior treatments included chemoradiation therapy (n=2) and chemotherapy with autologous bone marrow transplantation (n=1). Correlative imaging data were available in all patients and included skeletal radiographic survey (n=6), bone scan (n=3), and spinal CT or MRI (n=4), and were all obtained within 3 months of the PET study. Validation was by clinical or imaging follow-up. RESULTS: In three patients with both pre- and post-therapy PET scans, PET demonstrated a favorable treatment response, by showing a decline in lesion metabolic activity (n=1), or progression of disease, by showing development of new lesions or higher lesion glucose metabolism (n=2), concordant with the clinical evaluation, while the other imaging studies showed no discernible interval changes. PET detected multiple hypermetabolic lesions in one patient with a negative bone scan and concordant positive skeletal radiographic survey. Bone scans underestimated the extent of disease in two other patients in comparison with PET. PET also detected a few early marrow lesions with subtle radiographic changes while all radiographically aggressive lytic lesions corresponded to intense hypermetabolism on PET. CONCLUSION: PET can detect early marrow involvement of multiple myeloma and is useful in assessing the extent of active disease at the time of initial presentation and in evaluating treatment response.

Adult↗
PubMed2002

Incidental colonic fluorodeoxyglucose uptake: correlation with colonoscopic and histopathologic findings.

PURPOSE: To evaluate the pattern and degree of incidental colonic fluorodeoxyglucose (FDG) uptake in patients without colorectal carcinoma who underwent whole-body FDG positron emission tomography (PET) for other purposes and compare them with colonoscopic and/or histopathologic findings. MATERIALS AND METHODS: Cases of 27 patients without known history of colorectal carcinoma who were referred for evaluation with whole-body FDG PET and displayed incidental colonic uptake were reviewed retrospectively. Colonoscopy was performed in 10 patients; histopathologic analysis, in two; and both, in 15. The colonic FDG uptake patterns were nodular-focal, nodular-multifocal, segmental, and diffuse. The FDG uptake level was scored with a four-point scale in relation to hepatic uptake. Binomial distribution was used to calculate 95% CIs for the probability of finding an abnormality at histologic examination, as predicted by findings at FDG PET. RESULTS: Colonoscopic findings in eight patients with a diffuse uptake pattern were normal. Thirteen patients with nodular high FDG uptake had pathologic findings. Six (22%) of the 27 patients were not suspected of having a malignancy, and seven had benign neoplasms. With a 95% CI, nodular high FDG uptake implies at least a 79% chance that histopathologic findings may be abnormal. Colitis was seen in five of six patients with a segmental pattern of high FDG uptake. CONCLUSION: Colonoscopy is a reasonable next step for further diagnostic examination of patients who display nodular high FDG uptake in the colon. Diffuse FDG uptake often is associated with normal findings at colonoscopy, while segmental high uptake may imply inflammation.

Adult↗
PubMed1999

Evaluation of Rare Tumors with [F-18]Fluorodeoxyglucose Positron Emission Tomography.

The purpose of this paper was to evaluate the utility of positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (FDG) in the clinical assessment of rare tumors. We identified 6 patients over the last 18 months with rare tumors who were referred for PET imaging at the time of initial diagnosis, for tumor surveillance or for posttherapy reevaluation. The PET findings were compared with follow-up clinical data, the results of other imaging modalities and histology. FDG PET correctly detected disease in patients with anaplastic thyroid cancer, pleural mesothelioma, myxoid liposarcoma, malignant fibrous histiocytoma, synovial cell sarcoma and uterine leiomyosarcoma. These findings suggest that PET is useful in the evaluation of a variety of rare tumors both for initial preoperative staging and post-therapy assessment. Further experience with other uncommon tumors is necessary to define the precise role of FDG PET in this clinical setting.

Journal Article↗
PubMedDate not supplied

2-deoxy-2-[F-18]fluoro-D-glucose-positron emission tomography/computed tomography imaging evaluation of esophageal cancer.

We evaluated the clinical utility of 2-deoxy-2-[F-18]fluoro-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) on the precise localization of pathologic foci and exclusion of normal variants in the imaging evaluation of patients with esophageal carcinoma. Combined PET/CT scans were performed in 60 patients (50 males, 10 females, age range 47-84 years) with history of esophageal carcinoma either at the time of initial diagnosis (group I, n=14) or for surveillance and/or detection of recurrent and metastatic disease (group II, n=46). Prior treatments included esophagectomy with gastric pull-up (n=23), surgery and chemotherapy (n=3), surgery and chemoradiation therapy (n=10), chemotherapy alone (n=5), radiation therapy alone (n=2), and chemoradiation without surgery (n=3). Diagnostic validation was by tissue sampling in three patients and clinical/radiological follow-up for up to 1.5 years in the remaining patients. In group I, discordant abnormalities were noted in seven patients. PET demonstrated hypermetabolism in normal-size lymph nodes on CT in three patients that were considered likely true positive in view of concurrent existence of other adjacent enlarged hypermetabolic lymph nodes in the same nodal basin. Hypometabolic incidental CT abnormalities of up to 1-cm lung nodules were noted in three patients and pleural effusion in one patient, which were considered true negative in view of no change on follow-up PET/CT studies. In group II, both PET and CT showed concordant abnormalities in 23 patients. The precise image fusion of hypermetabolism in a liver lesion allowed a diagnostic CT-guided biopsy in one patient. PET demonstrated true positive hypermetabolic abnormalities in four patients that localized to structures, which were normal by noncontrast CT criteria, and true negative in one patient with hepatic fatty deposits. PET showed decline in metabolic activity of the primary lesion in one patient after chemotherapy, while the corresponding CT abnormality remained unchanged. PET/CT image fusion provided relevant complementary diagnostic information in 14 patients with discordant findings (23% of total) that resulted in biopsy in three cases, institution of chemotherapy in four cases, and a wait-and-watch strategy in seven cases. In conclusion, our findings add to the current body of literature that suggests that FDG-PET/CT scanning may improve the imaging evaluation of patients with esophageal cancer by providing complementary structural-metabolic information. In particular, our findings support the notion that PET/CT may be the most appropriate imaging modality in the evaluation of patients of esophageal cancer that may impact patient management.

Aged↗
PubMedDate not supplied

Pharmacologic interventions in nuclear radiology: indications, imaging protocols, and clinical results.

Nuclear radiology is valuable in assessing pathophysiology of a variety of organ systems. Pharmacologic interventions are often employed in radionuclide imaging to monitor the physiologic changes, which in turn facilitate the diagnosis. Metoclopramide, erythromycin, and cisapride have been used for gastric emptying studies. To overcome false-negative results, cimetidine, pentagastrin, and glucagon have been used in imaging of Meckel diverticula. Pharmacologic intervention with either cholecystokinin-8 or morphine is used primarily for the assessment of diseases of the gallbladder, common bile duct, and sphincter of Oddi. Pharmacologic interventions performed during renography include diuretic administration, angiotensin-converting enzyme inhibition, and aspirin renography. Recombinant thyrotropin can be used in patients with previously treated thyroid carcinoma who require lifelong follow-up for recurrent disease. Cardiac pharmacologic stress agents fall into two categories: coronary vasodilating agents, such as dipyridamole and adenosine, and cardiac positive inotropic agents, such as dobutamine and arbutamine. Measurement of hemodynamic responses to pharmacologic flow augmentation with carbon dioxide or acetazolamide is valuable in cerebrovascular perfusion studies.

Acetazolamide↗
PubMedDate not supplied

Glucose metabolism of human prostate cancer mouse xenografts.

We hypothesized that the glucose metabolism of prostate cancer is modulated by androgen. We performed in vivo biodistribution and imaging studies of [F-18] fluorodeoxyglucose (FDG) accumulation in androgen-sensitive (CWR-22) and androgen-independent (PC-3) human prostate cancer xenografts implanted in castrated and noncastrated male athymic mice. The growth pattern of the CWR-22 tumor was best approximated by an exponential function (tumor size in mm3 = 14.913 e(0.1086 x days), R2 = .96, n = 5). The growth pattern of the PC-3 tumor was best approximated by a quadratic function (tumor size in mm3 = 0.3511 x days2 + 49.418 x day - 753.33, R2 = .96, n = 3). The FDG accumulation in the CWR-22 tumor implanted in the castrated mice was significantly lower, by an average of 55%, in comparison to that implanted in the noncastrated host (1.27 vs. 2.83, respectively, p < .05). The 3-week maximal standardized uptake value (SUVmax) was 0.99 +/- 0.43 (mean +/- SD) for CWR-22 and 1.21 +/- 0.32 for PC-3, respectively. The 5-week SUVmax was 1.22 +/- 0.08 for CWR-22 and 1.35 +/- 0.17 for PC-3, respectively. The background muscle SUVmax was 0.53 +/- 0.11. Glucose metabolism was higher in the PC-3 tumor than in the CWR-22 tumor at both the 3-week (by 18%) and the 5-week (by 9.6%) micro-PET imaging sessions. Our results support the notions that FDG PET may be useful in the imaging evaluation of response to androgen ablation therapy and in the early prediction of hormone refractoriness in men with metastatic prostate cancer.

Androgens↗
PubMedDate not supplied

FDG PET in suspected recurrent and metastatic prostate cancer.

Development of an accurate non-invasive imaging technique to detect recurrent and metastatic prostate cancer is critical for the effective management of these patients. The purpose of our study was to determine the diagnostic utility of positron emission tomography with [F-18]fluorodeoxyglucose (FDG PET) in patients with suspected or known metastatic and recurrent prostate cancer. We performed 12 FDG PET scans in 12 men (age 65-81 years) with history of prostate cancer who had previously undergone radical prostatectomy (n=3) or prostate radiotherapy (n=9). Serum prostate specific antigen (PSA) level was elevated in all patients (5-206 ng/ml). Available correlative imaging studies included contrast-enhanced chest, abdomen and pelvis CT (n=8), bone scintigraphy (n=5), and radiography (n=2). PET findings were compared to the findings of the other imaging studies on a lesion-by-lesion basis in individual patients. Validation was by clinical or imaging follow-up for up to 1 year. PET findings were concordant with the findings of the other imaging studies in 7 patients. PET was discordant with the other imaging studies in 5 patients. PET demonstrated suspicious hypermetabolic pelvic lymph nodes in one patient with negative pelvis CT. PET underestimated the extent of osseous metastatic disease in the remaining 4 patients. FDG PET is limited in the detection of osseous metastatic lesions but may be useful in the detection of metastatic nodal and soft tissue disease.

Aged↗