ABSTRACT
Solitary fibrous tumors (SFTs) are rare spindle cell neoplasms of mesenchymal origin that are most commonly found in the pleura, although they have also been documented in extrapleural locations. SFTs affect males and females in equal distribution, and they typically occur between the fourth and seventh decades of life. Since SFTs are usually benign and asymptomatic, the majority of them are discovered incidentally on computed tomography (CT) or magnetic resonance imaging (MRI) imaging, unless they grow to a size that causes mass effect symptoms on other organs. Nonetheless, imaging is not sufficient to diagnose an SFT, and therefore, biopsy is recommended for further analysis. Advances in immunohistochemistry and molecular diagnostics have identified CD34 and NAB2-STAT6, respectively, as the most consistent markers for SFTs. The risk of SFT metastasis can be determined through the use of a four-variable risk-stratification model developed by Demicco et al., which is based upon the risk factors of patient age, tumor size, mitotic count per 10 high-power fields, and the degree of tumor necrosis. The management of SFTs involves a wide surgical resection of the tumor while preserving surrounding organs and structures. Post-operative surveillance involves imaging the primary tumor site for up to five years due to the risk of local recurrence. At this time, neither radiation therapy nor chemotherapy after resection have yet to show benefit, and therefore, they are not currently recommended. This case report discusses the management of a 68-year-old woman who was diagnosed with a malignant extrapleural SFT in her right medial upper thigh.
ABSTRACT
Identifying the mechanisms behind neuronal fate specification are key to understanding normal neural development in addition to neurodevelopmental disorders such as autism and schizophrenia. In vivo cell fate specification is difficult to study in vertebrates. However, the nematode Caenorhabditis elegans, with its invariant cell lineage and simple nervous system of 302 neurons, is an ideal organism to explore the earliest stages of neural development. We used a comparative transcriptome approach to examine the role of cnd-1/NeuroD1 in C. elegans nervous system development and function. This basic helix-loop-helix transcription factor is deeply conserved across phyla and plays a crucial role in cell fate specification in both the vertebrate nervous system and pancreas. We find that cnd-1 controls expression of ceh-5, a Vax2-like homeobox class transcription factor, in the RME head motorneurons and PVQ tail interneurons. We also show that cnd-1 functions redundantly with the Hox gene ceh-13/labial in defining the fate of DD1 and DD2 embryonic ventral nerve cord motorneurons. These data highlight the utility of comparative transcriptomes for identifying transcription factor targets and understanding gene regulatory networks.
