The clinical efficacy of (18)F-FDG-PET/CT in benign and malignant musculoskeletal tumors.

OBJECTIVE: Most of the current clinical data on the role of 2-[(18)F]fluoro-2-deoxy-D -glucose positron emission tomography ((18)F-FDG-PET) in musculoskeletal tumors come from patients studied with PET and less frequently with hardware fusion PET/computed tomography (CT). And the number of cases in each report is too small to clarify the exact clinical efficacy of PET or PET/CT. This prompted us to analyze our experience with (18)F-FDG-PET/CT in a relatively large group of patients with musculoskeletal tumors. METHODS: (18)F-FDG-PET/CT was performed on 91 patients from May 2004 to June 2007. The final diagnosis was obtained from surgical biopsy in 83 patients (91%) and clinical follow-up in 8 (9%). We analyzed the characteristics and amount of (18)F-FDG uptake in soft tissue and bone tumors, and investigated the ability of (18)F-FDG-PET/CT to differentiate malignant from benign tumors. The cutoff maximum standardized uptake value (SUV(max)) was calculated using the receiver-operation characteristic curve method. Sensitivity, specificity, and diagnostic accuracy were calculated with cutoff SUV(max) and the final diagnosis. Unpaired t test was used for the statistical analysis. RESULTS: Final diagnosis revealed 19 benign soft tissue tumors (mean SUV(max) 4.7), 27 benign bone tumors (5.1), 25 malignant soft tissue tumors (8.8), and 20 malignant bone tumors (10.8). There was a significant difference in SUV(max) between benign and malignant musculoskeletal tumors in total (P < 0.002), soft tissue tumors (P < 0.05), and bone tumors (P < 0.02). Sensitivity, specificity, and diagnostic accuracy were 80%, 65.2%, and 73% in total with cutoff SUV(max) 3.8, 80%, 68.4%, and 75% in the soft tissue tumors with cutoff SUV(max) 3.8, and 80%, 63%, and 70% in the bone tumors with cutoff SUV(max) 3.7. CONCLUSIONS: (18)F-FDG-PET/CT reliably differentiated malignant soft tissue and bone tumors from benign ones, although there were many false-positive and false negative lesions. Further studies with all kinds of musculoskeletal tumors in large numbers are needed to improve the diagnostic accuracy of (18)F-FDG-PET/CT.

A Case of Pheochromocytoma with Ganglioneuronal Differentiation Producing Vasoactive Intestinal Peptide / 대한내분비학회지

Vasoactive intestinal peptide(VIP) is a 28-amino acid peptide, which may cause secretory diarrhea by stimulating the production of adenylate cyclase. Neuroendocrine tumors, secreting vasoactive intestinal peptide (VIP), are almost always of a pancreatic in origin. However, a pheochromocytoma may produce several neuropeptides, containing VIP, as they are considered to be neuroendocrine tumors. A 57-year-old woman, who presented with chronic watery diarrhea, hypokalemia, weight loss and a left adrenal mass, is described. Histologically, the tumor was diagnosed as a pheoch-romocytoma, with ganglioneuronal differentiation, and was histochemically confirmed to produce a vasoactive intestinal polypeptide. A left adrenal VIP-producing pheochromocytoma was successfully resected. After surgery, her diarrhea subsided and the electrolytes, affected neuroendocrine hormone levels, blood pressure and blood sugar level were normalized.

A Case of Acute Thrombotic Renal Artery Occlusion Treated with Local Urokinase Infusion

Acute thrombotic renal artery occlusion is rarely identified at premortem. Early diagnosis and treatment are crucial for salvage of renal function. We reported a case of successfully dissolved acute thrombotic occlusion of renal artery of 9 hour duration with intra-arterial infusion of urokinase in a 83-year-old man.

A Case of Primary Malignant Mesenchymoma of the Heart

A malignant mesenchymoma is a rare soft tissue neoplasm that show at least two types of malignant mesenchymal differentiation, in addition to poorly differentiated fibrosarcomatous elements. They grow rapidly, recur frequently, and can be found in a wide variety of location, with most occurring in the extremities. A primary malignant mesenchymoma of the heart is extremely rare, with only 20 cases having been reported worldwide in the English literature up to 2002. We experienced a case of primary cardiac malignant mesenchymoma in a 59 year old female patient, who was admitted due to exertional dyspnea. This case is reported, with a review of the relevant literature.

Mycobacterium Avium Arthritis with Extra-articular Abscess in a Patient with Mixed Connective Tissue Disease

A case of Mycobacterium avium arthritis in a 39-year-old female patient with mixed connective tissue disease (MCTD) was reported. An extra-articular abscess had formed outside the knee joint and extended down the calf. A culture was taken of the abscess and synovial fluid disclosed Mycobacteriun avium. This was resistant to most anti-tuberculosis agents. A combination of anti-tuberculosis drugs followed a total resection of the abscess. We concluded that M avium septic arthritis could insidiously develop into an extra-articular abscess. A combination of anti-tuberculosis drugs with a total resection of the abscess was an effective treatment.

A Case of Severe Asthma Complicated with Pneumoperitoneum and Pneumomediastinum During AMBU Ventilation / 결핵

Pneumoperitoneum, Pneumomediastinum, subcutaneous emphysema and a pneumothorax are some of the mechanical complications of bronchial asthma. The incidence of pneumoperitoneum during an attack of acute asthma is rare. The pathogenesis is free gas track from the overdistended alveoli, through the bronchovascular sheaths to the mediastinum. If the high pressure is maintained, air can escape retroperitoneally into the abdomen and burst into the peritoneal cavity. A 43-year-old woman was admitted due to a severe asthma attack. She was required endotracheal intubation and AMBU(air mask bag unit) ventilation. Immediately after these procedures, pneumoperiotneum, pneumomediastinum, and subcutaneous emphysema daveloped. She was treated with mechanical ventilation and medical therapy. The pneumoperitoneum was resolved after 27 days. Here, we report this case with the review of the relevant literature.