Upregulation of FGFR1 expression is associated with parathyroid carcinogenesis in HPT-JT syndrome due to an HRPT2 splicing mutation.

Mutations of the HRPT2 gene, which are responsible for hyperparathyroidism-jaw tumor (HPT-JT) syndrome, have been implicated in the development of a high proportion of parathyroid carcinomas. The aim of this study was to investigate differences in expression of the most important genes connected with parathyroid carcinoma between HPT-JT syndrome due to an HRPT2 splicing mutation, normal parathyroid tissue and sporadic parathyroid adenoma. Total RNAs were extracted from parathyroid carcinoma in HPT-JT syndrome harbouring HRPT2 splicing mutation or sporadic parathyroid adenoma and normal parathyroid gland, and subjected to Illumina DASL-based gene expression assay. Unsupervised hierarchical clustering analysis was used to compare gene expression in HPT-JT syndrome, sporadic parathyroid adenoma and normal parathyroid glands. We identified differentially regulated genes in HPT-JT syndrome and sporadic parathyroid adenoma relative to normal parathyroid glands using a combination of Welch's t-test and fold-change analysis. Quantitative PCR, RT-PCR and IHC were used for validation. Sixteen genes differentially regulated in the parathyroid carcinoma were associated with signal pathways, MAPK, regulation of actin cytoskeleton, prostate cancer and apoptosis. FGFR1 expression was confirmed to be significantly upregulated by validation experiments. Our gene expression profiling experiments suggest that upregulated FGFR1 expression appears to be associated with parathyroid carcinoma in HPT-JT syndrome due to an HRPT2 splicing mutation.

An unusual presentation of Hoffa's disease in an elderly patient with no trauma history: a case report.

Hoffa' s fat pad disease usually occurs in young active patients participating in activities involving repetitive microtrauma to the knee joint. No specific radiographic findings associated with the disease has yet been defined. We report an elderly patient who presented with a 12-month anterior knee pain and limited knee extension, without any trauma history. Radiographs showed a calcified soft tissue mass in the Hoffa's fat pad. Magnetic resonance imaging showed the lesion had a generalized heterogeneous hypointensity on T1- and T2-weighted images and a poorly defined margin. The lesion was excised arthroscopically, and histopathological examination revealed fat pad adipocyte necrosis, mucoid degeneration, and dystrophic calcification, suggesting Hoffa's disease. The present report indicates that Hoffa's disease can occur in elderly patients with no trauma history, can be associated with a calcified lesion on radiographs, and can be linked to infrapatellar fat pad degeneration in such patients.

Primary cutaneous Ewing's sarcoma/primitive neuroectodermal tumor manifesting numerous small and huge ulcerated masses: its complete remission by chemotherapy and magnetic resonance imaging findings.

Extraskeletal Ewing's sarcoma (ES) and primitive neuroectodermal tumor (PNET) are widely regarded as clinically and histologically identical tumors which consist of small blue round cells. Extraskeletal ESs/PNETs usually occur in the deep soft tissues of the paraspinal region, chest wall, or lower extremities. However, superficially located cases, so-called cutaneous ESs/PNETs, are exceedingly rare, and the vast majority of the reported cases present as a single small mass. We present magnetic resonance imaging (MRI) findings and clinical course of a unique case of primary cutaneous ES/PNET presenting as numerous huge masses with severe ulceration on them.

Cystic fibrous dysplasia in the long bone.

Prominent osteolysis associated with "ground glass" density of fibrous dysplasia may indicate cystic change or sarcomatous transformation. This complication has been reported only sporadically in the long bones. This article presents clinical, radiographic, and pathologic findings, and outcome of simple curettage and bone graft observed in a series of 8 patients with prominent cystic fibrous dysplasia of the long bone. Magnetic resonance imaging features provide a basis for separation of benign cystic change from malignant transformation. However, biopsy is necessary to distinguish nonspecific cystic degeneration from secondary aneurysmal bone cyst. Simple curettage with allo-chip-bone graft is an effective treatment for cystic fibrous dysplasia.

Gastric cancer acrometastases to all digits of one hand following closed intramedullary nailing.

Metastatic malignant tumor of the hand is unusual and the most common site of the primary cancer is lung. Acrometastases to the phalanges of the hand usually involve a single bone, while those proximal to the phalanges often involve multiple bones. Metastasis to the hand from gastrointestinal cancer, particularly from gastric cancer, is extremely rare. To our knowledge, only five cases have been reported in the literature to date and there has been no reported case following closed intramedullary nailing for metastatic diaphyseal fracture of an ipsilateral long bone. We present a very unusual case of gastric cancer, which metastasized to all fingertips of the ipsilateral hand after closed interlocking intramedullary nailing of a pathologic fracture of the humerus.

Desmoid tumor of bone with enchondromatous nodules, mistaken for chondrosarcoma.

Desmoid tumor of bone, also termed desmoplastic fibroma or aggressive fibromatosis, is a rare, locally aggressive fibroblastic tumor. We present a 16-year-old male with a huge desmoid tumor involving the iliac wing. It was associated with enchondromatous nodules mimicking malignancy. The tumor in this patient was mistaken for chondrosarcoma and hemipelvectomy was performed. To our knowledge, such a case has not previously been documented fully in the English literature. The radiographic and pathologic findings and a possible mechanism of enchondromatous nodule formation in fibrous bone tumors are discussed.