| Angiomatoid fibrous histiocytoma | |
|---|---|
 | |
| Micrograph showing an angiomatoid fibrous histiocytoma. H&E stain. |
Angiomatoid fibrous histiocytoma(AFH) is a rare soft tissue cancer that affects children and young adults.
| Angiomatoid fibrous histiocytoma | |
|---|---|
| | |
| Micrograph showing an angiomatoid fibrous histiocytoma. H&E stain. |
Angiomatoid fibrous histiocytoma(AFH) is a rare soft tissue cancer that affects children and young adults.
It is characterized by cystic blood-filled spaces and composed of histiocyte-like cells. A lymphocytic cuff is common. It often simulates a vascular lesion, and was initially described as doing this. [1]
AFH typically has a chromosomal translocation involving the ATF1 gene -- t(12;16) FUS/ATF1 or t(12;22) EWS/ATF1. [2]
 | This section is empty. You can help by adding to it. (December 2017) |
| | This section is empty. You can help by adding to it. (December 2017) |
Liposarcomas are the most common subtype of soft tissue sarcomas, accounting for at least 20% of all sarcomas in adults. Soft tissue sarcomas are rare neoplasms with over 150 different histological subtypes or forms. Liposarcomas arise from the precursor lipoblasts of the adipocytes in adipose tissues. Adipose tissues are distributed throughout the body, including such sites as the deep and more superficial layers of subcutaneous tissues as well as in less surgically accessible sites like the retroperitoneum and visceral fat inside the abdominal cavity.
Fibrosarcoma is a malignant mesenchymal tumour derived from fibrous connective tissue and characterized by the presence of immature proliferating fibroblasts or undifferentiated anaplastic spindle cells in a storiform pattern. Fibrosarcomas mainly arise in people between the ages of 25 and 79. It originates in fibrous tissues of the bone and invades long or flat bones such as the femur, tibia, and mandible. It also involves the periosteum and overlying muscle.
Desmoplastic small-round-cell tumor (DSRCT) is an aggressive and rare cancer that primarily occurs as masses in the abdomen. Other areas affected may include the lymph nodes, the lining of the abdomen, diaphragm, spleen, liver, chest wall, skull, spinal cord, large intestine, small intestine, bladder, brain, lungs, testicles, ovaries, and the pelvis. Reported sites of metastatic spread include the liver, lungs, lymph nodes, brain, skull, and bones. It is characterized by the EWS-WT1 fusion protein.
Nodular fasciitis (NF) is a benign, soft tissue tumor composed of myofibroblasts that typically occurs in subcutaneous tissue, fascia, and/or muscles. The literature sometimes titles rare NF variants according to their tissue locations. The most frequently used and important of these are cranial fasciitis and intravascular fasciitis. In 2020, the World Health Organization classified nodular fasciitis as in the category of benign fibroblastic/myofibroblastic tumors. NF is the most common of the benign fibroblastic proliferative tumors of soft tissue.
Ewing sarcoma is a type of pediatric cancer that forms in bone or soft tissue. Symptoms may include swelling and pain at the site of the tumor, fever, and a bone fracture. The most common areas where it begins are the legs, pelvis, and chest wall. In about 25% of cases, the cancer has already spread to other parts of the body at the time of diagnosis. Complications may include a pleural effusion or paraplegia.
Cyclic AMP-dependent transcription factor ATF-1 is a protein that in humans is encoded by the ATF1 gene.
RNA-binding protein EWS is a protein that in humans is encoded by the EWSR1 gene on human chromosome 22, specifically 22q12.2. It is one of 3 proteins in the FET protein family.
ERG is an oncogene. ERG is a member of the ETS family of transcription factors. The ERG gene encodes for a protein, also called ERG, that functions as a transcriptional regulator. Genes in the ETS family regulate embryonic development, cell proliferation, differentiation, angiogenesis, inflammation, and apoptosis.
Giant cell fibroblastoma (GCF) is a rare type of soft-tissue tumor marked by painless nodules in the dermis and subcutaneous tissue. These tumors may come back after surgery, but they do not spread to other parts of the body. They occur mostly in boys. GCF tumor tissues consist of bland spindle-shaped or stellate-shaped cells interspersed among multinucleated giant cells.
Acute megakaryoblastic leukemia (AMKL) is life-threatening leukemia in which malignant megakaryoblasts proliferate abnormally and injure various tissues. Megakaryoblasts are the most immature precursor cells in a platelet-forming lineage; they mature to promegakaryocytes and, ultimately, megakaryocytes which cells shed membrane-enclosed particles, i.e. platelets, into the circulation. Platelets are critical for the normal clotting of blood. While malignant megakaryoblasts usually are the predominant proliferating and tissue-damaging cells, their similarly malignant descendants, promegakaryocytes and megakaryocytes, are variable contributors to the malignancy.
A myxoid liposarcoma is a malignant adipose tissue neoplasm of myxoid appearance histologically.
Clear cell sarcoma is a rare form of cancer called a sarcoma. It is known to occur mainly in the soft tissues and dermis. Rare forms were thought to occur in the gastrointestinal tract before they were discovered to be different and redesignated as gastrointestinal neuroectodermal tumors.
Extraskeletal myxoid chondrosarcoma (EMC) is a rare low-grade malignant mesenchymal neoplasm of the soft tissues, that differs from other sarcomas by unique histology and characteristic chromosomal translocations. There is an uncertain differentiation and neuroendocrine differentiation is even possible.
Low-grade fibromyxoid sarcoma (LGFMS) is a rare type of low-grade sarcoma first described by H. L. Evans in 1987. LGFMS are soft tissue tumors of the mesenchyme-derived connective tissues; on microscopic examination, they are found to be composed of spindle-shaped cells that resemble fibroblasts. These fibroblastic, spindle-shaped cells are neoplastic cells that in most cases of LGFMS express fusion genes, i.e. genes composed of parts of two different genes that form as a result of mutations. The World Health Organization (2020) classified LGFMS as a specific type of tumor in the category of malignant fibroblastic and myofibroblastic tumors.
EWS/FLI1 is an oncogenic protein that is pathognomonic for Ewing sarcoma. It is found in approximately 90% of all Ewing sarcoma tumors with the remaining 10% of fusions substituting one fusion partner with a closely related family member.
Proliferative fasciitis and proliferative myositis (PF/PM) are rare benign soft tissue lesions that increase in size over several weeks and often regress over the ensuing 1–3 months. The lesions in PF/PM are typically obvious tumors or swellings. Historically, many studies had grouped the two descriptive forms of PF/PM as similar disorders with the exception that proliferative fasciitis occurs in subcutaneous tissues while proliferative myositis occurs in muscle tissues. In 2020, the World Health Organization agreed with this view and defined these lesions as virtually identical disorders termed proliferative fasciitis/proliferative myositis or proliferative fasciitis and proliferative myositis. The Organization also classified them as one of the various forms of the fibroblastic and myofibroblastic tumors.
Fibroblastic and myofibroblastic tumors (FMTs) develop from the mesenchymal stem cells which differentiate into fibroblasts and/or the myocytes/myoblasts that differentiate into muscle cells. FMTs are a heterogeneous group of soft tissue neoplasms. The World Health Organization (2020) defined tumors as being FMTs based on their morphology and, more importantly, newly discovered abnormalities in the expression levels of key gene products made by these tumors' neoplastic cells. Histopathologically, FMTs consist of neoplastic connective tissue cells which have differented into cells that have microscopic appearances resembling fibroblasts and/or myofibroblasts. The fibroblastic cells are characterized as spindle-shaped cells with inconspicuous nucleoli that express vimentin, an intracellular protein typically found in mesenchymal cells, and CD34, a cell surface membrane glycoprotein. Myofibroblastic cells are plumper with more abundant cytoplasm and more prominent nucleoli; they express smooth muscle marker proteins such as smooth muscle actins, desmin, and caldesmon. The World Health Organization further classified FMTs into four tumor forms based on their varying levels of aggressiveness: benign, intermediate, intermediate, and malignant.
Sclerosing epithelioid fibrosarcoma (SEF) is a very rare malignant tumor of soft tissues that on microscopic examination consists of small round or ovoid neoplastic epithelioid fibroblast-like cells, i.e. cells that have features resembling both epithelioid cells and fibroblasts. In 2020, the World Health Organization classified SEF as a distinct tumor type in the category of malignant fibroblastic and myofibroblastic tumors. However, current studies have reported that low-grade fibromyxoid sarcoma (LGFMS) has many clinically and pathologically important features characteristic of SEF; these studies suggest that LGSFMS may be an early form of, and over time progress to become, a SEF. Since the World Health Organization has classified LGFMS as one of the malignant fibroblastic and myofibroblastic tumors that is distinctly different than SEF, SEF and LGFMS are here regarded as different tumor forms.
The FET protein family consists of three similarly structured and functioning proteins. They and the genes in the FET gene family which encode them are: 1) the EWSR1 protein encoded by the EWSR1 gene located at band 12.2 of the long arm of chromosome 22; 2) the FUS protein encoded by the FUS gene located at band 16 on the short arm of chromosome 16; and 3) the TAF15 protein encoded by the TAF15 gene located at band 12 on the long arm of chromosome 7 The FET in this protein family's name derives from the first letters of FUS, EWSR1, and TAF15.
Angiofibroma of soft tissue (AFST), also termed angiofibroma, not otherwise specified, is a recently recognized and rare disorder that was classified in the category of benign fibroblastic and myofibroblastic tumors by the World Health Organization in 2020. An AFST tumor is a neoplasm that was first described by A. Mariño-Enríquez and C.D. Fletcher in 2012.
Further to the characterization of the recurrent chromosomal rearrangements that result in the EWSR1-CREB1, t(12;22)(q13;q12) EWSR1-ATF1, and t(12;16)(q13;p11) FUS-ATF1 gene fusions, AFH is of course now established as a translocation-associated neoplasm.
 | This oncology article is a stub. You can help Wikipedia by expanding it. |