Solitary vertebral metastatic glioblastoma in the absence of primary brain tumor relapse: a case report and literature review.

BACKGROUND: Metastatic glioblastoma presenting as a solitary osteolytic cervical vertebral mass without primary brain tumor relapse is extremely rare with only 1 reported case in the literature. Because of its rarity, it can be easily overlooked and misdiagnosed, posing a diagnostic dilemma. CASE PRESENTATION: A 51-year-old man with right temporal glioblastoma was initially treated by tumor resection, radiotherapy and chemotherapy. Eighteen months after surgery, he was readmitted with complaints of neck pain for 2 weeks. Follow-up magnetic resonance imaging (MRI) and fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed a solitary FDG-avid osteolytic lesion in the 4th cervical vertebral body without other abnormal FDG-uptake in the body and in the absence of local recurrence at the resection cavity. Because of the sudden worsening situation and intractable neck pain, the patient underwent tumor resection. Postoperatively, the pain was obviously reduced and the situation was improved. Interestingly, the immunohistochemical findings of glial fibrillary acidic protein (GFAP) indicated the characteristic of metastatic glioblastoma, despite that the histopathological findings of Hematoxylin & Eosin (H&E) staining was suspicious of osteoclastoma. According to the clinical history, imaging findings, pathological and immunohistochemical results, a final diagnosis of solitary vertebral metastasis from glioblastoma without central nervous system (CNS) relapse was confirmed. Then, the patient received radiotherapy on spine and adjuvant chemotherapy with temozolomide. However, he died suddenly 2 months after the tumor resection, nearly 21 months after the initial diagnosis. CONCLUSION: We emphasize that metastatic glioblastoma should be considered in the differential diagnosis of a solitary FDG-avid osteolytic vertebral mass on PET/CT. And the diagnosis of extracranial metastasis (ECM) from glioblastoma can be achieved through clinical history, imaging findings, pathological examination, and immunohistochemical staining with GFAP.

Extracranial bone metastases from recurrent anaplastic astrocytoma on FDG PET/CT: A case report a care-compliant article.

OBJECTIVE: Extracranial bone metastases from astrocytoma are rare and frequently detected as part of multiorgan metastases. It is extremely rare for astrocytoma to have extracranial bone metastases alone. The importance of whole-body fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging in evaluating extracranial metastasis (ECMs) has not been described effectively due to the rarity of this event. The purpose of our case report is to emphasize the role of FDG PET/CT in the assessment of tumor recurrence and extracranial bone metastases from anaplastic astrocytoma. METHODS AND MATERIALS: A 25-year-old woman was firstly admitted with a 4-month history of progressive blurred vision, and 2-month history of intermittent headache. Presurgical MRI imaging revealed a large mass in the left trigone of lateral ventricle. Subsequently, she underwent tumor resection, radiotherapy and chemotherapy. A final pathological diagnosis of anaplastic astrocytoma (WHO III) was made. Nearly 12 months after the surgery, the follow-up brain MR imaging revealed a contrast-enhanced lesion in the site of operative region. Whole-body FDG PET/CT imaging was performed to evaluate the situation. RESULTS: Postoperative brain FDG PET/CT showed an abnormal focal FDG uptake corresponding to the contrast-enhanced lesion in the operative area, suggesting a tumor recurrence. Whole-body FDG PET/CT also showed multiple FDG-avid osteosclerotic lesions in the body. It was highly suggestive of extracranial bone metastases. A subsequent open bone biopsy of FDG-avid lesion in right iliac crest was performed. Histopathological and immunohistochemical findings indicated characteristic of glioma. The patient died 1 month later, nearly 13 months after the initial diagnosis. CONCLUSIONS: ECMs from anaplastic astrocytoma are extremely rare but they do occur. Whole-body FDG PET/CT imaging with inclusion of brain was valuable in differentiating tumor recurrence from radiation necrosis and in detecting uncommon extracranial bone metastases from anaplastic astrocytoma, which were closely related to prognosis of this disease.

Solitary Choroidal Metastasis From Lung Adenocarcinoma on FDG PET/CT.

Solitary choroidal metastasis as an initial presentation of lung cancer is rare. A 67-year-old woman who initially presented with a 3-month history of blurred vision in the right eye was suggestive of choroidal melanoma on MRI. Preoperatively, a pulmonary mass was found on x-ray. She was referred for an FDG PET/CT imaging, which revealed a choroidal lesion with minimal FDG uptake in right eye and increased FDG activity in the known lung mass. A pathological diagnosis of metastatic lung adenocarcinoma was made after enucleation of the right eyeball.

FDG-Avid Keloid on PET/CT Imaging.

Keloid is a benign fibroproliferative growths resulting from an overexuberant healing response. A 51-year-old man with a 20-year history of keloid formation presented with a 1-year history of unexplained progressive weakness of both lower limbs. He was clinically suspected of having paraneoplastic neurologic syndrome. FDG PET/CT was performed to exclude underlying malignancy. FDG PET/CT revealed a giant FDG-avid keloid in the anterior chest wall without any other abnormal FDG uptake in the body. We emphasize that a benign FDG-avid keloid should be considered in the differential diagnosis of FDG-avid cutaneous lesions on PET/CT.

Blastic Plasmacytoid Dendritic Cell Neoplasm Evaluated by FDG PET/CT.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematological malignancy. A 34-year-old man with a biopsy-proven BPDCN underwent FDG PET/CT for staging. FDG PET/CT revealed multiple mild FDG-avid cutaneous lesions on the chest and back, involvement of left inguinal lymph node, and a markedly increased FDG-avid subcutaneous mass in the left lower leg.

Polysplenia Syndrome With Splenic and Skeletal Muscle Metastases From Thyroid Carcinoma Evaluated by FDG PET/CT: Case Report and Literature Review: A Care-Compliant Article.

Polysplenia syndrome (PSS) is a rare congenital abnormality. Metastases to spleen and skeletal muscle from differentiated thyroid cancer (DTC) are also extremely rare. Our case report aims to present an interesting case of PSS associated with splenic metastasis (SM) and skeletal muscle metastasis (SMM) from advanced papillary thyroid carcinoma which was evaluated on fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). An 84-year-old Chinese man was admitted with the history of multiple enlarged masses in bilateral neck, right axillary, and inguinal areas for >2 months. The results of ultrasonography examination were highly suggestive of malignancy. The histological results of the following biopsy were consistent with papillary thyroid carcinoma with involvement of multiple regional lymph nodes. He was referred for an FDG PET/CT imaging to evaluate the situation. FDG PET/CT showed that an intense FDG-avid thyroid mass with widespread regional lymph node involvement and distant metastases in the body. Unexpected sites of metastases were detected in the spleens and skeletal muscles. Most interestingly, FDG PET/CT imaging also described the typical imaging findings of PSS including the 2 right-sided spleens, azygos and hemiazygos continuation of inferior vena cava (IVC), right-sided stomach, middle line liver, a short pancreas, preduodenal portal vein (PPV), and malrotation of gut. Whole body FDG PET/CT imaging can accurately evaluate the situation of DTC by detecting regional lymph node involvement, common and rare sites of distant metastases which are closely related to staging, management, and prognosis of this disease. Whole-body FDG PET/CT is also valuable in demonstrating the typical imaging features of PSS.

Extensive invasive extramammary Paget disease evaluated by F-18 FDG PET/CT: a case report.

Extramammary Paget disease (EMPD) is a rare cutaneous, intraepithelial adenocarcinoma. Because of its rarity, little is known about the value of fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in evaluating this disease. Our case report aims to increase current knowledge of FDG PET/CT in EMPD as a noninvasive imaging tool for assessing the extension of the disease and detecting distant metastases.We reported a 64-year-old Chinese man who presented with a slowly progressive, ill-margined erythematous lesion with a crusted, eroded, and scaly surface involving multiple sites of penis, scrotum, left pelvic wall, hip, groin, and thigh for >4 years, which became extensive in the past 1 year. He was referred for an FDG PET/CT examination to further evaluate the lesions. A following skin biopsy was performed to obtain a definitive histological diagnosis.FDG PET/CT imaging revealed mild FDG uptake at the extensive cutaneous lesion with subcutaneous invasion, involvement of lymph nodes, and multiple intense FDG-avid of skeletal metastases. According to the appearance of FDG PET/CT, a provisional diagnosis of advanced cutaneous malignancy was made. Histopathology findings indicated characteristic of EMPD. The patient was treated with radiation therapy and died from complications 2 months after the last dose of radiotherapy.Our case highlighted that a whole-body FDG PET/CT should be incorporated into the diagnostic algorithm of EMPD to give a comprehensive assessment of this disease.

Primary anorectal melanoma on FDG PET/CT.

Primary anorectal melanoma is an extremely rare, aggressive malignancy with a poor prognosis. A 76-year-old man with a 2-month history of rectal bleeding, anal pain, and tenesmus was referred for an F-FDG PET/CT examination, which revealed an abnormal focal FDG uptake on the lower rectum with multiple other intense FDG-avid regions in locoregional pelvic lymph nodes, bones, liver, and lung. It was highly suggestive of malignancy, and a provisional diagnosis of advanced rectal carcinoma was made. However, a following tissue biopsy of the lesion on the lower rectum performed by colonoscopy histopathologically indicated primary anorectal melanoma.

[Cerebral glucose metabolism in Parkinson's disease with dementia].

OBJECTIVE: To assess the regional cerebral glucose utilization and the imaging characteristic of Parkinson's disease with dementia (PDD) with (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). METHODS: Questionnaire survey, mini-mental state examination (MMSE), physical examination, and FDG PET on brain at rest state were performed on 20 patients with PDD, 13 males and 7 females, aged (70 +/- 6), and sex- and age-matched 8 patients with non-demented PD, and 30 healthy parsons. Visual inspection and statistical parametric mapping (SPM) were used to investigate the regional cerebral metabolic rate of glucose (rCMRglc) and the distribution of the tracer. RESULTS: The MMSE score of the PDD group was (27.5 +/- 2.4), (10 - 24), significantly lower than those of the non-PDD group [(27.5 +/- 2.4) (22 - 30)] and control group [(27.9 +/- 2.2) (21 - 30)] (F = 60.31, P = 0.000). There were no significant differences in Hoehn-Yahr staging and disease courses between the two PD groups (P > 0.05). Visual inspection showed that there were no significant focal hypometabolic areas in the imaging of the non-demented PD patients, while compared to the controls, the rCMRglc levels of the PDD patients decreased in bilateral superior parietal lobules (BA 7), inferior parietal lobules (BA 40, 39), superior frontal gyri (BA 6), middle frontal gyri (BA 6, 8, 9), middle temporal gyri (BA 21), cuneate lobes (BA 17, 18, 19), cingulate cortices (BA 31), lingual gyri (BA 19) basal ganglia, and thalamus. According to the severity of memory impairment and the onset of hallucination, the subtype of PDD was classified into memory impairment dominant group (MD) and hallucination dominant group (HD). The rCMRglc of MD subgroup decreased significantly in the parietotemporal association cortex, especially in the precuneus lobe. The rCMRglc of the HD subgroup decreased significantly in the occipital cortex. There were no significant differences in MMSE score and Hoehn-Yahr staging between the MD and HD groups (both P > 0.05), while the age of the HD subgroup was significantly lower, and the disease duration of the HD subgroup was significantly longer than those toe MD group (both P < 0.05). CONCLUSIONS: (18)F-FDG/PET imaging is helpful to the diagnosis of PDD and may help investigate the potential pathophysiology of PDD.