Clustering of deletions on chromosome 13 in benign and low-malignant lipomatous tumors

Deletions and structural rearrangements of the long arm of chromosome 13 are frequently observed in benign and low-malignant lipomatous tumors, but nothing is known about their molecular genetic consequences. We assessed the karyotypes of 40 new and 22 previously published cases (35 ordinary lipomas, 15 spindle cell/pleomorphic lipomas, 2 myxolipomas, 1 angiomyxolipoma and 9 atypical lipomatous tumors) with chromosome 13-abnormalities, and found bands 13q12-22 to be frequently affected. Twenty-seven cases with structural abnormalities within this region were selected for breakpoint and deletion mapping by metaphase fluorescence in situ hybridization (FISH), using a set of 20 probes. Deletions were found in 23 of 27 cases. The remaining 4 cases had seemingly balanced rearrangements. The breakpoints were scattered but clustered to band 13q14, and in all cases with unbalanced abnormalities, a limited region within band 13q14 was partially or completely deleted. A deletion within band 13q14 was found together with a breakpoint on the other homologue in 5 cases, 4 of which could be tested further with regard to the status of the retinoblastoma (RB1)-gene. In all 4 cases, only 1 copy of the gene was deleted. In addition to the breaks and deletions in the vicinity of the RB1-locus, several other regions of 13q were recurrently affected, e.g., in the vicinity of the hereditary breast cancer (BRCA2; 13q12)- and lipoma HMGIC fusion partner (LHFP; 13q13)- genes. Our findings strongly indicate that deletion of a limited region (approximately 2.5 Mbp) within 13q14, distal to the RB1-locus, is of importance in the development of a subset of lipomatous tumors.     

Isolated intraosseous gout in hallux sesamoid mimicking a bone tumor in a teenaged patient

We are reporting an unusual case of isolated intraosseous tophus in medial hallux sesamoid presenting as tumor-like lesion in a teenage patient without prior history of gouty attack and underlying systemic disorders. The lesion manifested isointensity to surrounding muscles with internal low signal on spin echo (SE) T1-weighted images, and heterogeneous low signal intensity on fast spin echo (FSE) T2-weighted images. Computed tomography (CT) scan disclosed expansion and diffusely increased attenuation of the medial hallux sesamoid with focal cortical erosion and extraosseous extension of high attenuation content. The subsequent resection and pathology revealed intraosseous tophus deposition, which is particularly rare at this site and at this age. Imaging studies revealed some characteristic imaging features which can retrospectively be attributed to gouty tophus. When an expansile osteolytic lesion manifesting low signal intensity on T2-weighted image and internal calcifications on CT scan is encountered, the possibility of intraosseous tophus should be included in the list of differential diagnoses, even in a teenage patient without prior history of gout.     

Effects of variation in systemic blood pressure on intraosseous pressure, PO2, and PCO2

Several regulatory mechanisms have been shown to influence the intraosseous circulation. The influence of general hypovolemia on bone circulation and possible regulatory effects were investigated by recording the intraosseous pressure and PO2 and PCO2 continuously by mass spectrometry in rabbits. Hypovolemia was induced by repeated bleedings. The intraosseous and arterial pressures were found to be linearly related. The intraosseous PO2 already decreased after the first step of bleeding and decreased more than 50% of the initial value after an average blood loss of 40 ml. The intraosseous PCO2 showed an opposite pattern. The experimental PO2 vs. arterial pressure curves were similar to curves obtained by a computer simulation that assumes the blood flow to be proportional to the intraosseous pressure.     

Sclerotic lipoma: lipomas simulating sclerotic fibroma

Aims: We report a series of five unusual subcutaneous lipomas characterized by prominent stromal sclerosis in a storiform arrangement. Methods and results: All lesions occurred in young male adults (23.0 ± 9.5 years), three lesions were on the scalp and two on the hands. Clinically, lipoma, chondroma or some form of cyst were suspected. In contrast to sclerotic fibroma (‘circumscribed storiform collagenoma’) a variable number of adipocytes were interspersed within the fibrosclerotic background. These cells also showed immunoreactivity for S100 protein as well as intracytoplasmic lipid deposits ultrastructurally. None of the lesions recurred within a follow-up period of between 0.5 and 9 years. Conclusions: Our series suggests that sclerotic lipomas should be classified with fibro- and myxolipomas, angiolipomas, spindle cell and pleomorphic lipomas, as an additional characteristic subtype of lipoma. Sclerotic lipomas are often misdiagnosed as a sclerotic fibroma, but are essentially fatty tumours and are, at least in our small series, not associated with Cowden's disease.     

A case of atypical inter-muscular lipoma (Evans).

A case of a 51-year-old woman with a lipoma-like tumor on the right arm which showed rapid recurrence after the first simple excision is reported. On the second surgical operation, a lipoma-like tumor with extensive growth between the biceps muscle and brachialis muscle of the right arm was noted. Histological examination revealed almost mature fat cells and scattered atypical lipoblast-like cells. For the treatment of an atypical inter-muscular lipoma, complete excision is necessary, although very extensive treatment is not recommended.     

Lumbosacral lipoma causing tethering of the conus: Case report

We report a case of tethered cord syndrome treated surgically. As in many reported cases, the treatment was successful on pain but only partially so on sphincter dysfunction. The most important diagnostic investigation is CT scanning with contrast medium.

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Sommario Viene riportato un caso con sindrome da tethered cord trattato chirurgicamete. Come in molti dei casi riportati il trattamento ha avuto successo per il dolore, ma solo parzialmente per le disfunzioni sfinteriche. La più importante indagine diagnostica è la CT dopo somministrazione intradurale di mezzo di contrasto.

     

Duodenal Lipoma -A Report of Two Cases Resected by Endoscopic Polypectomy-

Duodenal lipomas are rarely reported. We reported two asymptomatic pedunculated duodenal lipomas successfully resected by endoscopic polypectomy. Case 1 was a 48-year-old Chinese female who came for a physical check-up. Upper gastrointestinal series and endoscopic examination revealed a 2.0 × 1.0 cm pedunculated polyp in the posterior wall of the bulb. Case 2 was a 67-year-old female. A 1.7 times 1.0 cm olive-shaped pedunculated polyp was found by endoscopic examination during a health check-up. Both tumors were polypectomised by endoscopy and proven to be duodenal lipomas pathologically. The diagnosis of duodenal lipoma has largely been made by surgery and autopsy in the past. It may be made nowadays with abdominal computed tomography and repeated deep biopsies. Duodenal lipomas may be treated by endoscopic polypectomy if the tumor is small and pedunculated.>     

A Case of Terminal Ileum Lipoma Treated by Endoscopic Polypectomy

Abstract: This study reports on the case of a 71-year-old man who complained of repeated episodes of right lower abdominal pain. A barium enema and colonoscopy revealed a 20 times 20 times 15 mm smooth-surfaced polypoid tumor (Yamada type III) located in the terminal ileum. An endoscopy showed that the lesion had a slightly yellowish surface and the cushion sign was observed, so the tumor was considered to be an intestinal lipoma. During colonoscopy, prolapse of the tumor occurred through the orifice of Bauhin's valve and the patient simultaneously complained of right lower abdominal pain. The tumor was removed endoscopically. After a colonoscopic polypectomy, the patient's right lower abdominal pain disappeared. A pathological examination of the specimen revealed a lipoma of the terminal ileum. In general, the correct preoperative diagnosis of intestinal lipoma is difficult. Furthermore, 80% of lipomas situated at the terminal ileum are complicated by acute intussusception. We suggest that a colonoscopic polypectomy is a useful procedure for confirming the diagnosis of intestinal lipoma and for the prophylaxis of intussusception when the tumor is located in the terminal ileum.     

Ekbom's syndrome of photomyoclonus, cerebellar ataxia and cervical lipoma is associated with the tRNALys A8344G mutation in mitochondrial DNA

We have investigated nine maternal offsprings to patients with a hereditary syndrome of cerebellar ataxia, photomyoclonus, skeletal deformities and lipoma, originally described by Ekbom. The nine family members underwent a thorough neurological examination, neurophysiological investigations and molecular genetic analysis of mtDNA from lymphocytes and muscle. Clinical examination showed a partial syndrome in one relative and minor signs and symptoms in three additional offsprings. We found the heteroplasmic tRNA^LyS A8344G point mutation in mtDNA in all investigated maternal offsprings. The fraction of mutated mtDNA ranged from 33 to 87% in lymphocytes and from 59 to 92% in muscle tissue. Analysis of mtDNA from a lipoma showed a high level (96%) of the tRNA^LyS A8344G mutation. We conclude that Ekbom's syndrome is a mitochondrial encephalomyopathy associated with the same heteroplasmic tRNA mutation as seen in myoclonus epilepsy with ragged-red fiber (MERRF) syndrome.     

Surgical treatment supposed natural history of the tethered cord with occult spinal dysraphism

We retrospectively evaluated the pre- and postoperative course of 34 tethered cord patients with occult spinal dysraphism in an attempt to infer the natural history of this disorder and to determine the effectiveness of the surgical treatment. There were 32 cases with lumbosacral lipoma and 2 with tight filum terminale. The age at surgery ranged from 1 month to 47 years old. Eight patients, aged 1 month to 4 years old, were asymptomatic; 26 had neurogenic bladder (26 cases) or motor problems affecting the legs (8 cases). None of the patients older than 5 years of age were asymptomatic. Untethering of the spinal cord was performed in all cases. The postoperative follow-up period ranged from 5 months to 11 years. During these periods, 7 (88%) of the 8 asymptomatic patients remained neurologically intact, 6 (23%) of the 26 symptomatic patients showed improved symptoms, and 15 patients (58%) remained unchanged. These results indicate that the neurological symptoms will appear progressively in the tethered cord patients, and that prophylactic surgery should be considered as early as possible. Received: 22 March 1996 Revised: 10 August 1996