SOX-10 and MiTF expression in cellular and 'mixed' neurothekeoma.

BACKGROUND: Neurothekeoma and nerve sheath myxoma have long been interpreted as related tumors that share nerve sheath linage. Lack of S100 expression in neurothekeoma and similarities of gene expression profiles between neurothekeoma and fibrohistiocytic tumors have created reasonable doubt about this concept. SOX-10 represents a marker for schwannian and melanocytic differentiation, and is expressed in other tumors of nerve sheath linage. Microphthalmia transcription factor (MiTF) expression has been repeatedly reported in cellular neurothekeoma in the recent literature and was proposed as a helpful marker in this entity. METHODS: We investigated 25 cases of cellular neurothekeoma, 8 cases of mixed neurothekeoma and 1 case of nerve sheath myxoma for the expression of SOX-10, MiTF, S100, NKI/C3, Melan-A and smooth muscle actin (SMA) using immunohistochemistry. RESULTS: A lack of SOX-10 expression was demonstrated in 100% of cellular and mixed neurothekeomas, but was present in the case of nerve sheath myxoma. More than two thirds of neurothekeomas showed very focal or no reactivity with MiTF. CONCLUSIONS: Our data suggest that neurothekeoma and nerve sheath myxoma are unrelated, and that cellular and mixed neurothekeoma may not be of nerve sheath lineage. In addition, MiTF should not be regarded as a useful marker in neurothekeoma.

Prevalence of primary spinal tumors: 15-year data from Siriraj Hospital.

OBJECTIVE: To determine prevalence, demographic data and clinical presentation of primary vertebral tumors. MATERIAL AND METHOD: A retrospective study of the primary spine tumor specimens from Siriraj bone tumor registry from 1996 to 2010. RESULTS: From the study, primary spinal tumors constituted 85 of 1,679 bone tumor cases (5.06%). The common benign spinal tumors were giant cell tumor and hemangioma. The common malignant spinal tumors were chordoma, chondrosarcoma, and osteosarcoma. The mean age ofpresentation was 44.68 years. Fifty-three percent of tumors occurred in females. Pain was the most common presenting symptom, occurring in 73.53% of malignant and 52.94% of benign tumors. Neurological involvement occurred in 25% of malignant tumor Malignant lesions predominated in the sacral region while the most common location ofbenign specimens was thoracic region. CONCLUSION: The present study was the first demographic study ofprimary spinal tumor in Thai showed variety of prevalence when compared with similar studies based on Western patients. Whether these results reflect differences in the population, race and data collection method.

Rat bite fever caused by Streptobacillus notomytis mimicking pyogenic polyarthritis: A case report.

We report the world's sixth case of rat bite fever caused by Streptobacillus notomytis that mimicked pyogenic polyarthritis and required surgical debridement in combination with prolonged antibiotic therapy. This case report highlights the higher severity of rat bite fever caused by S. notomytis compared to S. moniliformis.

Synovial osteochondromatosis mimicking juvenile idiopathic arthritis in an adolescent: a case-based review.

Synovial osteochondromatosis is an extremely rare benign condition in children and adolescents that have joint pain as a presenting manifestation. It is usually monoarticular with the knee as the most common affected joint. In this article, we describe the case of a female adolescent suffering from debilitating chronic right knee pain initially mimicking juvenile idiopathic arthritis, who was subsequently diagnosed with primary synovial osteochondromatosis. We present a review of synovial osteochondromatosis focusing on the clinical manifestations, radiographic features, histopathologic findings, and treatment, with a summarized review of pediatric patients with initial musculoskeletal presentations who were ultimately diagnosed as synovial osteochondromatosis. Although synovial osteochondromatosis is rare in children and adolescents, this condition should be included in the differential diagnosis of joint pain and may mimic juvenile idiopathic arthritis. Appropriate diagnostic radiography, including both plain radiography and magnetic resonance imaging, is necessary to accurately diagnose this condition. We also emphasize the importance of a multidisciplinary team approach to managing patients with synovial osteochondromatosis.

Non-Hodgkin lymphoma with adrenal insufficiency: a case report and literature review.

A 62-year-old Thai man was admitted because of nausea and vomiting with incidentally detected bilateral adrenal enlargement. The basal cortisol was low and ACTH level was elevated CT guided percutaneous needle biopsy of adrenal gland showed a diffuse infiltration of medium to large atypical lymphoid cells of B-cell immunophenotype, which are diagnostic for a diffuse large B-cell lymphoma. Involvement by large B-cell lymphoma was documented in bone marrow biopsy as well. The findings confirmed the diagnosis of primary adrenal insufficiency caused by large B-cell lymphoma involving both adrenal glands.

Primary extraskeletal osteosarcoma in the pineal region. Case report.

Primary extraskeletal osteosarcoma occurring in the brain parenchyma is distinctly uncommon, with only five cases having been reported. The authors describe the case of a 45-year-old man who presented with progressive headache and diplopia. Computerized tomography scanning and magnetic resonance imaging results revealed a pineal region tumor with obstructive hydrocephalus. The patient underwent partial resection of the tumor. The histological examination showed large pleomorphic tumor cells embedded in osteoid matrix. Immunohistochemical analysis was negative for various antibodies and thus excluded a glial, germ cell, epithelial, and lymphoid tumor origin. Only vimentin showed strong positivity in most of the tumor cells. Ultrastructurally, the tumor cells were rich in dilated rough endoplasmic reticula. Clear zones between tumor cells and osteoid matrix were observed. The osteoid matrix was made up of small collagen fibrils and hydroxyapatite deposits. The tumor was not attached to the bone structure of the skull. These findings are consistent with the features of extraskeletal osteosarcoma. Data from complete medical and radiological studies excluded a metastatic origin for this tumor. Partial resection and postoperative radiotherapy had provided tumor control at 11 months after the onset of symptoms. This is the first reported case of a primary extraskeletal osteosarcoma occurring in the pineal region.

The management of sacral schwannoma: report of four cases and review of literature.

Sacral schwannoma is a rare retrorectal tumor in adults. Postoperative sacral neurological deficit is difficult to avoid. Currently, there is no established consensus regarding best treatment options. We present the management and outcomes of sacral schwannoma in 4 patients treated with intralesional curettage and postoperative radiation. There were 3 women and one man (average age: 45.5 years) with long duration of lumbosacral pain with or without radiculopathy. Intralesional curettage was performed by posterior approach and adjuvant radiation therapy with dosage of 5000-6600 cGy was given after surgery. The mean follow-up time was 18 months (range 4-23 months). Symptoms of radiculopathy had decreased in all patients. The recent radiographic findings show evidence of sclerosis at the sacrum one year postoperatively, but the size was unchanged. Intralesional curettage and adjuvant radiation therapy can be used in the treatment of sacral schwannoma to relieve symptoms and preserve neurological function.