Elastofibroma dorsi – differential diagnosis in chest wall tumours

BACKGROUND: Elastofibromas are benign soft tissue tumours mostly of the infrascapular region between the thoracic wall, the serratus anterior and the latissimus dorsi muscle with a prevalence of up to 24% in the elderly. The pathogenesis of the lesion is still unclear, but repetitive microtrauma by friction between the scapula and the thoracic wall may cause the reactive hyperproliferation of fibroelastic tissue. METHODS: We present a series of seven cases with elastofibroma dorsi with reference to clinical findings, further clinical course and functional results after resection, as well as recurrence. Data were obtained retrospectively by clinical examination, phone calls to the patients' general practitioners and charts review. Follow-up time ranged from four months to nine years and averaged 53 months. RESULTS: The patients presented with swelling of the infrascapular region or snapping scapula. In three cases, the lesion was painful. The ratio men/women was 2/5 with a mean age of 64 years. The tumor sizes ranged from 3 to 13 cm. The typical macroscopic aspect was characterized as poorly defined fibroelastic soft tissue lesion with a white and yellow cut surface caused by intermingled remnants of fatty tissue. Microscopically, the lesions consisted of broad collagenous strands and densely packed enlarged and fragmented elastic fibres with mostly round shapes. In all patients but one, postoperative seroma (which had to be punctuated) occurred after resection; however, at follow-up time, no patient reported any decrease of function or sensation at the shoulder or the arm of the operated side. None of the patients experienced a relapse. CONCLUSION: In differential diagnosis of soft tissue tumors located at this specific site, elastofibroma should be considered as likely diagnosis. Due to its benign behaviour, the tumor should be resected only in symptomatic patients

Michaelis–Menten networks are structurally stable

We consider a class of biological networks where the nodes are associated with first-order linear dynamics and their interactions, which can be either activating or inhibitory, are modelled by nonlinear Michaelis–Menten functions (i.e., Hill functions with unitary Hill coefficient), possibly in the presence of external constant inputs. We show that all the systems belonging to this class admit at most one strictly positive equilibrium, which is stable; this property is structural, i.e., it holds for any possible choice of the parameter values, and topology-independent, i.e., it holds for any possible topology of the interaction network. When the network is strongly connected, the strictly positive equilibrium is the only equilibrium of the system if and only if the network includes either at least one inhibiting function, or a strictly positive external input (otherwise, the zero vector is an equilibrium). The proposed stability results hold also for more general classes of interaction functions, and even in the presence of arbitrary delays in the interactions

[The management of obstructive jaundice in pancreatic cancer].

Patients with pancreatic cancer often present with advanced disease; so, curative surgical resection is possible in a small number of patients. Palliation in these patients focuses particularly on relief of biliary obstruction. Palliative treatment modalities include both surgical and nonsurgical approaches. Biliary obstruction is initially treated with endoscopic biliary stenting, plastic or metallic stents. Both of these provide similar initial relief of biliary obstruction; however, plastic stents have a greater risk of occlusion and should be used in patients with short survival duration. Metallic stents have a greater initial cost, but provide an overall cost-saving in patients with expected survival more than 6 months. There is no evidence of benefit from routine stenting of jaundiced patients before resection. Surgical palliation for biliary obstruction should be primarily considered in patients who fail endoscopic or percutaneous biliary decompression or who develop gastroduodenal obstruction, It is also indicated for patients with good performance status and expected survival of over 6 months. Surgical decompression of biliary tree should be made with a choledochojejunostomy whenever feasible, associated to a gastroduodenal bypass

Two case reports of a false aneuurism of the sphenopalatine artery after Lefort I osteotomy

False aneurysms and arteriovenous fistulas are rare complications of orthognathic surgery. The vessel most commonly involved with false aneurysms following mandibular surgery is the internal maxillary artery, and this vessel, especially the sphenopalatine branch, may also be involved following maxillary surgery. An unusual factor in the presentation of false aneurysms following Le Fort I osteotomies is an initial episode of epistaxis occurring greater than 2 weeks postoperatively. Arteriovenous fistulas following orthognathic surgery are more apt to involve large vessels, especially the internal carotid artery. Embolization procedures are the treatment of choice for false aneurysms and arteriovenous fistulas in the maxillofacial region following orthognathic surgery

Value of 18-fluorodeoxyglucose positron emission tomography in the patients with cystic tumors of the pancreas

OBJECTIVE: To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas. SUMMARY BACKGROUND DATA: The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer. METHODS: During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst. RESULTS: Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively. CONCLUSIONS: 18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both