F-18 FDG positron emission tomography in primary breast non-Hodgkin's lymphoma.

A 50-year-old woman had an irregular, mobile, firm right breast mass that became progressively larger in the past 3 months that measured 18 x 15 cm at the time of examination. She had no nipple discharge or skin changes. A 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) showed a ring-shaped breast uptake consisting of high peripheral glycolytic activity and a cold center most likely representing necrosis or hemorrhage despite the absence of a history of trauma, surgical intervention, chemotherapy, or radiation to the breast. Whole-body images did not show any evidence of lymph node involvement or distant metastases. These results were confirmed by computed tomography of the chest, abdomen, and pelvis. Cytologic examination of a fine-needle aspiration of the breast mass showed diffuse large B-cell, intermediate grade, non-Hodgkin's lymphoma. Although it occurs infrequently, primary breast lymphoma should be considered in patients with a breast mass that shows a ring-shaped FDG uptake. A PET scan, in contrast to other imagining techniques, offers the advantage of screening the entire body, excluding the presence of metastases, and confirming the primary origin of the breast lymphoma.

Glutaric aciduria type II: observations in seven patients with neonatal- and late-onset disease.

The clinical, biochemical, and neuroradiologic findings and clinical follow-up of seven patients with glutaric aciduria type II are reported. Three phenotypes of the disease are encountered: neonatal-onset form with congenital anomalies (two patients) or without congenital anomalies (three patients) and late-onset form (two patients). The neonatal-onset form presents as an overwhelming illness, with severe hypoglycemia and metabolic acidosis leading to rapid death. Frequently it is associated with perinatal energy deprivation, a neonate with low birth weight and prematurity. The late-onset form presents with intermittent episodes of vomiting, hypoglycemia, and acidosis especially after meals rich in fat and/or proteins. All parents are consanguineous and have a first- or second-degree relationship. Initially, in the two phenotypes with neonatal onset and during crisis in the late-onset phenotype, routine laboratory evaluation showed severe metabolic acidosis, with an increased anion gap, hypoglycemia without ketonuria, and disturbed liver function tests. In the majority of patients with neonatal-onset forms, the kidneys, liver, and at times the spleen are enlarged with an increased echogenic pattern; however, no hepatic or renal cysts are detected. Cardiomegaly is observed in most patients. The diagnosis can be easily and rapidly reached through tandem mass spectrometry study of the blood and can further be confirmed by gas chromatography/mass spectrometry analysis of the urine organic acids. In this report, the magnetic resonance imaging/computed tomography brain studies showed brain atrophy, white matter disease, and in one patient, fluid-filled cavities in the periventricular area and putamina. Fluorine-18-labeled 2-fluoro-2-deoxyglucose positron emission tomographic (FDG PET) brain studies in two patients with late-onset disease showed slightly decreased activity in the cerebral cortex in one and in the caudate nuclei in the other. Brain FDG PET scan and magnetic resonance spectroscopy were normal in one patient with neonatal-onset disease. All patients were treated with a diet low in fat and protein, oral riboflavin, and carnitine. The results were promising for the late-onset disease. Intravenous carnitine gave rewarding results in one patient with neonatal-onset disease.

F-18 fluorodeoxyglucose chest uptake in lung inflammation and infection.

PURPOSE: F-18 fluorodeoxyglucose (FDG) may accumulate at sites of inflammation or infection, making interpretation of whole-body scans difficult in patients with cancer. METHODS: More than 650 whole-body positron emission tomographic (PET) scans performed to examine patients with cancer were reviewed to identify uptake in pulmonary infection or inflammation based on the appearance of F-18 FDG chest uptake, chest radiographs, computed tomography, or all of these. RESULTS: Ten patients had uptake in benign lung disease. Eight patients had head and neck tumors and two patients had breast cancer. Intense focal or multifocal F-18 FDG chest uptake was seen in 6 of 10 scans. This was difficult to distinguish from pulmonary metastases based on the scan appearance. However, in the remaining patients, the uptake was atypical for malignancy and displayed an apical, segmental, or lobar pattern. In all patients, the F-18 FDG lung uptake corresponded to benign radiologic changes (infiltration, consolidation, or atelectasis), and the final diagnosis was pulmonary inflammation or infection. Nine patients were asymptomatic and one patient had clinical aspiration pneumonia. Follow-up PET scans were performed in five patients to evaluate their conditions. Chest uptake disappeared completely in three patients and partially in two patients, and there were no new findings. Variable degrees of F-18 FDG chest uptake have been reported with more than 40 different benign causes. They can be classified based on the underlying mechanism into four major categories: 1) Inflammation or infection, 2) benign tumor, 3) physiologic activity, and 4) iatrogenic. Most of these false-positive cases are included in the first category. CONCLUSIONS: Pulmonary infection or inflammation might predispose patients to localized F-18 FDG chest uptake mimicking pulmonary metastases and limiting the specificity of whole-body scans performed in patients with cancer.

Clinical, fluorine-18 labeled 2-fluoro-2-deoxyglucose positron emission tomography (FDG PET), MRI of the brain and biochemical observations in a patient with 4-hydroxybutyric aciduria; a progressive neurometabolic disease.

We report a five-year-old boy with 4-hydroxybutyric aciduria. The child presented with global developmental delay, severe hypotonia and myoclonic seizures. The urine 4-hydroxybutyric acid was 1038 times that of normal, and other organic acids related to its further metabolism were also increased. Electroencephalography showed findings indicative of cerebral dysfunction. However, other neurophysiological studies were normal. Clinical improvement was observed after the administration of vigabatrin and dextromethorphan. Magnetic resonance imaging of the brain revealed cerebellar vermin atrophy and subtle white matter changes in the cerebral hemispheres. Fluorine-18 labeled 2-fluoro-2-deoxyglucose positron emission tomographic (FDG PET) scan of the brain showed a marked decrease in the cerebellar metabolism, probably related to atrophy of cerebellar vermis and secondary cerebellar deafferentation. FDG PET scan is found to be of value in the understanding and assessment of brain functional alterations. It may be useful in monitoring and optimizing treatment strategies of this rare disease.

Clinical and cerebral FDG PET scan in a patient with Krabbe's disease.

A 2-year, 6-month-old Saudi male with infantile Krabbe's disease was studied with fluorine-18-labeled-2-fluoro-2-deoxyglucose positron emission tomography (FDG PET) scan. The patient presented with a gradual loss of developmental milestones, irritability, and crying. At the advanced stage of the disease, he developed tonic-clonic seizures and became a microcephalic, extremely irritable, blind, spastic quadriplegic child, with no deep tendon reflexes. Laboratory studies revealed normal blood chemistry, muscle enzymes, very long chain fatty acids, and acylcarnitines. No abnormal urinary organic acids were detected. The cerebrospinal fluid protein concentration was increased. Magnetic resonance imaging of the brain revealed mild brain atrophy and white matter disease mainly in the centrum semiovale. Electroretinography was normal; however, electroencephalography and visual-evoked potentials were abnormal. Peripheral nerve conduction studies documented a demyelinating neuropathic process. The FDG PET study of the brain demonstrated a marked decrease in the metabolism of the left cerebral cortex and no uptake in the caudate heads. Normal glucose uptake was observed in the thalami, lentiform nuclei, and cerebellum. The patient did not present for subsequent clinic visits and is presumed dead.

99mTc-human serum albumin scans in children with protein-losing enteropathy.

UNLABELLED: Protein-losing enteropathy (PLE) can be diagnosed scintigraphically using 99mTc-human serum albumin (HSA) scans. METHODS: To evaluate the usefulness of this method in detecting enteric protein loss, we retrospectively reviewed the 99mTc-HSA scans of 18 children presenting consecutively with PLE. RESULTS: Enteric 99mTc-HSA uptake was noted in 12 patients (8 boys, 4 girls) with a mean age of 7.4 y. Early dynamic images showed abdominal uptake that was most likely in the small bowel in 91% of the scans. Delayed images showed abnormal accumulation that was localized in the colon in 73% and in the small bowel in 27% of the scans. A 4-mo follow-up scan obtained in 3 patients showed reduced HSA uptake after a high-protein, low-fat, medium-chain triglyceride oil-based diet and fat-soluble vitamins. Mean serum albumin, total protein, gammaglobulin, and calcium levels were significantly decreased. Ten patients (from 4 families) were diagnosed to have primary intestinal lymphangectasia. One patient had active Salmonella enterocolitis, and 1 had giardiosis. 99mTc-HSA was normal in the remaining 6 patients (3 boys, 3 girls) with a mean age of 3.5 y (range, 2-5 y). Mean serum albumin, total protein, gammaglobulin, and calcium levels were less decreased than those of the first group. Five of these patients had primary intestinal lymphangactesia (associated with infantile systemic hyalinosis in 1 patient). The remaining patient had normal duodenal biopsy, and the cause of protein loss remained unknown. CONCLUSION: The 99mTc-HSA scan is useful in the evaluation of children with PLE, especially those with severe hypoproteinemia and hypoalbuminemia, presumably reflecting a high rate of protein loss.

F-18 FDG uptake in breast infection and inflammation.

PURPOSE: Whole-body fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET) scanning has been useful in the management of breast cancer. However, F-18 FDG uptake sometimes has been associated with benign breast disease. Four cases are reported of F-18 FDG breast uptake caused by infectious or inflammatory mastitis that mimics malignant disease. METHODS AND RESULTS: Two women had F-18 FDG whole-body scans for the evaluation of a large breast mass after inconclusive results of ultrasonography. In both cases, intense focal F-18 FDG breast uptake was noted that mimicked breast cancer. Histologic examination showed, in one patient, chronic granulomatous infiltration that likely represented tuberculous mastitis, because she showed a good clinical response to empirical anti-tuberculous treatment. The second patient had lactational changes associated with acute inflammation, and the culture grew Staphylococcus aureus. The breast mass completely disappeared 3 weeks after a course of antibiotic treatment. The other two patients had staging F-18 FDG PET scans 1 and 12 months after lumpectomy for breast carcinoma to detect residual, recurrent, or metastatic disease. Both scans showed a ring-like uptake in the involved breast, with superimposed intense focal uptake suggesting tumor necrosis centrally and malignant foci peripherally. In both cases, histologic examination revealed hemorrhagic inflammation secondary to postsurgical hematomas and no evidence of malignancy. CONCLUSION: Acute or chronic infectious mastitis and postsurgical hemorrhagic inflammatory mastitis should be considered in patients who have a breast mass, especially those with a history of tenderness or surgery.

X-linked adrenoleukodystrophy. The Saudi experience.

OBJECTIVES: To evaluate the clinical, biochemical, neuroradiological, and neurophysiological findings of patients with X-linked adrenoleukodystrophy. METHODS: Retrospective study evaluating the data of 10 X-linked adrenoleukodystrophy patients diagnosed at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. RESULTS: The common presenting symptoms were deterioration in school performance, vision and hearing, behavioral changes, and seizures. Eight patients survived 1-4 years and one patient 12 years after the initial presentation, while one patient expired. Six patients had the childhood form, 3 had the adolescent form and one had the adrenomyeloneuropathy form. Six are in an advanced stage of the disease and 3 have mild to moderate spasticity. All except 2 manifested moderate to severe dementia with variable degrees of visual loss. Decreased hearing and features of adrenal insufficiency were seen in 7 patients. Very long chain fatty acids were significantly increased in seven and mildly elevated in 2 patients, however the C26 to C22 ratio was increased in all. The characteristic high-signal intensity of parieto-occipital white matter on brain magnetic resonance imaging T2-weighted images was observed in all patients. Two patients had functional study of the brain, which showed hypometabolic activity in gray and white matter of the occipital lobes. Various neurophysiological abnormalities were detected. The response to different treatment modalities was not promising. CONCLUSION: The disease is more common than had been previously recognized due to phenotypic variability and a wide spectrum of presentations. This report describes various aspects of this disorder and emphasizes the importance of early identification and treatment of asymptomatic but biochemically affected individuals, since all current therapeutic approaches are disappointing if overt neurological abnormalities have been already developed.

X-linked adrenoleukodystrophy. The Saudi experience.

OBJECTIVE: To evaluate the clinical, biochemical, neuroradiological, and neurophysiological findings of patients with X-linked adrenoleukodystrophy. METHODS: Retrospective study evaluating the data of 10 X-linked adrenoleukodystrophy patients diagnosed at King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia. RESULTS: The common presenting symptoms were deterioration in school performance, vision and hearing, behavioral changes, and seizures. Eight patients survived 1-4 years and one patient 12 years after the initial presentation, while one patient expired. Six patients had the childhood form, 3 had the adolescent form and one had the adrenomyeloneuropathy form. Six are in an advanced stage of the disease and 3 have mild to moderate spasticity. All except 2 manifested moderate to severe dementia with variable degrees of visual loss. Decreased hearing and features of adrenal insufficiency were seen in 7 patients. Very long chain fatty acids were significantly increased in seven and mildly elevated in 2 patients, however the C26 to C22 ratio was increased in all. The characteristic high-signal intensity of parieto-occipital white matter on brain magnetic resonance imaging T2-weighted images was observed in all patients. Two patients had functional study of the brain, which showed hypometabolic activity in gray and white matter of the occipital lobes. Various neurophysiological abnormalities were detected. The response to different treatment modalities was not promising. CONCLUSION: The disease is more common than had been previously recognized due to phenotypic variability and a wide spectrum of presentations. This report describes various aspects of this disorder and emphasizes the importance of early identification and treatment of asymptomatic but biochemically affected individuals, since all current therapeutic approaches are disappointing if overt neurological abnormalities have been already developed.

Radioiodine uptake in the head and neck.

OBJECTIVE: To report two cases of sinusitis-associated radioiodine uptake in patients with thyroid cancer and to review the reported causes of false-positive radioiodine uptake in the head and neck area. METHODS: We present the radiologic findings in two patients who had undergone treatment for papillary thyroid cancer and discuss other settings in which radioiodine uptake suggested the presence of metastatic disease. RESULTS: Radioiodine whole-body scans of two patients who had had thyroid cancer demonstrated uptake in the sphenoid and maxillary sinuses, respectively, mimicking bone or brain metastatic involvement. The thyroglobulin levels were low. Computed tomographic (CT) scanning disclosed mucosal swelling in the sinuses, consistent with sinusitis. The radioiodine uptake cleared on a follow-up scan in one case and was more localized than the CT findings in the other. Eighteen causes of false-positive radioiodine uptake in the head and neck area have been reported. On the basis of the mechanism of uptake, they can be classified into four categories: (1) physiologic uptake (ectopic thyroid tissue), (2) nonthyroidal pathologic conditions (dacryocystitis, sinusitis, sinus mucocele, sialadenitis, folliculitis, Warthin's tumor, parotid cyst, porencephaly, posttraumatic cerebromalacia, and inflammation due to dental disease or a nose ring), (3) internal retention (ectasia of the carotid artery and an artificial eye), and (4) external contamination by body secretions (sweat and nasal, tracheobronchial, lacrimal, and salivary secretions). The estimated prevalence of external contamination in the head and neck area on whole-body radioiodine scans is 0.3%. CONCLUSION: Physicians should rule out the presence of radioiodine uptake by inflamed mucosa of the paranasal sinuses, as well as various other causes of false-positive radioiodine uptake, before metastatic thyroid cancer in the head and neck area is diagnosed.

Cerebral fluorine-18 labeled 2-fluoro-2-deoxyglucose positron emission tomography (FDG PET), MRI, and clinical observations in a patient with infantile G(M1) gangliosidosis.

The clinical, biochemical, pathological and neuroradiological findings of a 2-year-old Saudi boy with infantile G(M1) gangliosidosis are reported. The patient had a progressive neurologic deterioration, manifesting with developmental regression, sensorimotor and psychointellectual dysfunction and generalized spasticity that started at 4 months of age. Cherry-red macula, facial dysmorphia, hepatomegaly, exaggerated startle response to sounds, skeletal dysplasia, and vacuolated foamy lymphocytes that contain finely fibrillar material in addition to lamellar membranes and electron-dense rounded bodies were seen. MRI of the brain demonstrated mild diffuse brain atrophy and features of delayed dysmyelination and demyelination. Brain FDG PET scan revealed a mild decrease in the basal ganglia uptake, and moderate to severe decrease in thalamic and visual cortex uptake, and an area of increased glucose uptake in the left frontal lobe, probably representing an active seizure focus. The functional changes indicated by FDG PET scan and the structural abnormalities shown on MRI were found to be complementary in the imaging evaluation of infantile G(M1) gangliosidosis.

Primary hypothyroidism-associated TSH-secreting pituitary adenoma/hyperplasia presenting as a bleeding nasal mass and extremely elevated TSH level.

A 41-year-old male with primary hypothyroidism and a huge TSH-secreting pituitary tumor presented with a bleeding nasal mass that was initially misdiagnosed as a paraganglioma. Other unique features of the case include lack of complaints related to hypothyroidism, an extremely elevated TSH level of 3474 mU/l, and a low prolactin level. The presence of primary hypothyroidism made differentiating TSH-secreting pituitary adenoma from secondary thyrotroph hyperplasia difficult. A low molar ratio of alpha-subunit to TSH on presentation, together with normalization of TSH level and a 50% reduction in the size of the tumor after 6 weeks of thyroxine replacement therapy, suggested the presence of thyrotroph hyperplasia. However, the lack of further decrease in the size of the tumor that was associated with increased metabolic activity on 18-FDG PET scan, intense uptake on octreotide scan, and an elevated alpha-subunit to TSH molar ratio despite the normalization of free T4 and TSH levels for 16 months suggested the coexistence of thyrotroph adenoma. Together, the findings support the view that thyrotroph adenoma/irreversible hyperplasia can result from long standing primary hypothyroidism.

Radioiodine uptake in inactive pulmonary tuberculosis.

Radioiodine may accumulate at sites of inflammation or infection. We have seen such accumulation in six thyroid cancer patients with a history of previously treated pulmonary tuberculosis. We also review the causes of false-positive radioiodine uptake in lung infection/inflammation. Eight foci of radioiodine uptake were seen on six iodine-123 diagnostic scans. In three foci, the uptake was focal and indistinguishable from thyroid cancer pulmonary metastases from thyroid cancer. In the remaining foci, the uptake appeared nonsegmental, linear or lobar, suggesting a false-positive finding. The uptake was unchanged, variable in appearance or non-persistent on follow-up scans and less extensive than the fibrocystic changes seen on chest radiographs. In the two patients studied, thyroid hormone level did not affect the radioiodine lung uptake and there was congruent gallium-67 uptake. None of the patients had any evidence of thyroid cancer recurrence or of reactivation of tuberculosis and only two patients had chronic intermittent chest symptoms. Severe bronchiectasis, active tuberculosis, acute bronchitis, respiratory bronchiolitis, rheumatoid arthritis-associated lung disease and fungal infection such as Allescheria boydii and aspergillosis can lead to different patterns of radioiodine chest uptake mimicking pulmonary metastases. Pulmonary scarring secondary to tuberculosis may predispose to localized radioiodine accumulation even in the absence of clinically evident active infection. False-positive radioiodine uptake due to pulmonary infection/inflammation should be considered in thyroid cancer patients prior to the diagnosis of pulmonary metastases.

Bone mineral density of the spine and femur in healthy Saudi females: relation to vitamin D status, pregnancy, and lactation.

Bone mineral density (BMD) measurements of the anterio-posterior lumbar spine and the proximal femur using dual-energy x-ray absorptiometry, as well as relevant clinical and biochemical parameters, were determined in 321 healthy Saudi females in order to establish reference values and to study the effects of physical and lifestyle factors on BMD. Mean +/- SD of age, body mass index (BMI), number of pregnancies, and total duration of lactation were 35.4 +/- 11.3 years, 26.5 +/- 5.2 kg/m2, 3.1 +/- 3.1, and 23.7 +/- 42.4 months, respectively. Mean +/- SD of serum calcium, 25-hydroxyvitamin D (25OHD), and PTH levels were 2.37 +/- 0.09 mmol/liter, 24.5 +/- 17.2 nmol/liter, and 52.0 +/- 30.8 pg/ml, respectively. Peak BMD values were observed around age 35 years at the spine and earlier at the femur. Compared with USA females, Saudi females had lower weight-matched Z scores at the spine (-0.126 +/- 1. 078, P = 0.04), femoral neck (-0.234 +/- 0.846, P < 0.0001), and Ward's triangle (-0.269 +/- 1.015, P < 0.0001). Further, the prevalence of osteopenia and osteoporosis in subjects >/=31 years old were 18-41% and 0-7%, respectively, depending on the site examined. Severe hypovitaminosis D (25OHD level

PIP: This paper examines the relationship between bone mineral density (BMD) of the spine and femur and vitamin D status, pregnancy, and lactation among women in Saudi Arabia. The aims of the study are the following: 1) establish normative data for BMD at the anterio-posterior lumbar spine and femur using dual x-ray absorptiometry; 2) compare the BMD of Saudi females and their US counterparts; and 3) examine the relation of BMD to vitamin D status, pregnancy, and lactation. Samples included 321 healthy Saudi females recruited from the city of Riyadh, Saudi Arabia. Results suggest that the mean standard deviation (SD) of age, body mass index, number of pregnancies, and total duration of lactation were, respectively, 35.4 +or- 11.3 years, 26.5 +or- 5.2 kg/sq. m, 3.1 +or- 3.1, and 23.7 +or- 42.4 months. Mean +or- SD of serum calcium, 25-hydroxyvitamin D (25OHD), and PTH levels were 2.37 +or- 0.09 mmol/liter, 24.5 +or- 17.2 nmol/liter, and 52.0 +or- 30.8 pg/ml, respectively. Peak BMD values were observed around age 35 years at the spine and earlier at the femur. Compared with US females, Saudi females had lower weight-matched Z scores at the spine, femoral neck, and Ward's triangle. On the other hand, the number of pregnancies and total duration of lactation correlated with weight-matched BMD Z scores at the spine. This made the BMD in healthy Saudi females significantly lower than their US counterparts. This may due to the increase number of pregnancies and longer duration of lactation together with prevalent vitamin D deficiency.

F-18-FDG uptake in tuberculosis.

Two patients are described who showed abnormal fluorine-18 fluorodeoxyglucose (F-18 FDG) uptake that was due to benign disease, specifically tuberculous lymphadenitis and pneumonitis. The first patient had ulceration and oozing of the left nipple that was related to Paget's disease. An F-18 FDG PET, whole-body scan, which was performed for staging, showed no breast uptake. However, there was intense multifocal uptake in mediastinal, supraclavicular, and para-aortic areas that was confirmed radiologically to represent widespread lymphadenopathy. Pathologic examination of a mediastinal lymph node showed active tuberculosis. The second patient showed intense focal F-18 FDG uptake in mediastinal and supraclavicular areas and para-aortic lymphadenopathy due to non-Hodgkin's lymphoma. In addition, there was abnormal F-18 FDG lung uptake that revealed the presence of acid-fast bacilli on bronchial lavage. Intense focal F-18 FDG uptake in widespread lymphadenopathy or in the lung could be caused by infectious diseases such as tuberculosis. This possibility should be considered when whole-body scans of patients with cancer are interpreted, especially in those with a high incidence of infectious disease.

F-18 FDG whole-body positron emission tomography scan in primary breast sarcoma.

Three patients with primary breast sarcoma showed intense F-18 FDG breast uptake on the whole-body scan. In two patients the uptake was irregular and associated with cold foci that corresponded to hypodense lesions noted on the chest CT; these represented areas of pathologically demonstrated tumor necrosis. There was also intense FDG uptake in pulmonary, axillary, and supraclavicular lymph node metastases. All lesions were confirmed by CT scan of the chest. Thus F-18 FDG positron emission tomographic scanning accurately staged the tumors in these two patients, and it documented local recurrence in the third patient. Histopathologic examination showed evidence of a high-grade sarcoma, a primary rhabdomyosarcoma, and a malignant cystosarcoma phyllodes of the breast. Similar to breast carcinoma, F-18 FDG whole-body positron emission tomographic imaging could be useful in diagnosing and staging primary breast sarcomas.