|
Histiocytoma
A histiocytoma is a Tumor, tumour consisting of histiocytes. Histiocytes are Cells (biology), cells that are a part of the mononuclear phagocytic system, a part of the body's immune system that consists of phagocytic cells, which are responsible for engulfing solid particles by the cell membrane to form an internal phagosome by phagocytes and protists. Myxofibrosarcoma had been classified as a type of histiocytoma. However, the World Health Organization (2020) reclassified myxofibrosarcoma as a malignant tumor in the category of fibroblastic/myofibroblastic tumors. Types include: * benign fibrous histiocytoma: This tumor has also been termed benign fibrous histiocytomas of the skin, superficial/cutaneous benign fibrous histiocytomas, common fibrous histiocytoma, and more recently dermatofibroma. The use of "histiocytoma" in these terms refers more to the morphology (biology), morphologic appearance of some of the cells that comprise these lesions rather than their Cell lineage, lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histiocytoma (dog)
A histiocytoma in the dog is a benign tumor. It is an abnormal growth in the skin of histiocytes (histiocytosis), a cell that is part of the immune system. A similar disease in humans, Hashimoto-Pritzker disease, is also a Langerhans cell histiocytosis. Dog breeds that may be more at risk for this tumor include Bulldogs, American Pit Bull Terriers, American Staffordshire Terriers, Scottish Terriers, Greyhounds, Boxer (dog), Boxers, and Boston Terriers. They also rarely occur in goats and cattle. Histiocytic disorders A histiocyte is a differentiated tissue cell that has its origin in the bone marrow. The source for histiocytes is the monocyte/macrophage line. Monocytes (found in the blood) and macrophages (found in tissue) are responsible for phagocytosis (ingestion) of foreign material in the body. Langerhans cells are dendritic cells found in the skin and function by internalizing antigens (foreign particles) and presenting them to T cells. They arise from monocytes. Hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myxofibrosarcoma
Myxofibrosarcoma (MFS), although a rare type of tumor, is one of the most common soft tissue sarcomas, i.e. cancerous tumors, that develop in the soft tissues of elderly individuals. Initially considered to be a type of histiocytoma termed fibrous histiocytoma or myxoid variant of malignant fibrous histiocytoma, Angervall et al. termed this tumor myxofibrosarcoma in 1977. In 2020, the World Health Organization reclassified MFS as a separate and distinct tumor in the category of malignant fibroblastic and myofibroblastic tumors. MFS tumors are often treated by surgical resection. However, these tumors have high recurrence rates at the sites of their resections. Local recurrences followed by surgical resections may be repeated multiple times but during these cycles MFS tumors often progress from a lower grade to a higher more aggressive grade, metastasize, and become life-threatening. An uncommon variant of the MFS tumors termed epithelioid myxofibrosarcoma is even more likely to fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermatofibroma
A dermatofibroma, or benign fibrous histiocytomas, is a benign nodule in the skin, typically on the legs, elbows or chest of an adult. It is usually painless. It usually ranges from 0.2cm to 2cm in size but larger examples have been reported. It typically results from mild trauma such as an insect bite. Risk factors for developing multiple dermatofibromas include lupus, HIV, blood cancer and some medicines that weaken immunity. It is usually diagnosed by its appearance, but a biopsy may be required. Other bumps such as granular cell tumor, melanoma, clear cell acanthoma and dermatofibrosis lenticularis disseminata may look similar. Usually no treatment is needed. It can remain unchanged for years but can resolve spontaneously. Signs and symptoms Dermatofibromas are hard solitary slow-growing papules (rounded bumps) that appear in a variety of colours, usually brownish to tan. They are often elevated or pedunculated. A dermatofibroma is associated with the dimple sign; by appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benign Fibrous Histiocytoma
A dermatofibroma, or benign fibrous histiocytomas, is a benign nodule in the skin, typically on the legs, elbows or chest of an adult. It is usually painless. It usually ranges from 0.2cm to 2cm in size but larger examples have been reported. It typically results from mild trauma such as an insect bite. Risk factors for developing multiple dermatofibromas include lupus, HIV, blood cancer and some medicines that weaken immunity. It is usually diagnosed by its appearance, but a biopsy may be required. Other bumps such as granular cell tumor, melanoma, clear cell acanthoma and dermatofibrosis lenticularis disseminata may look similar. Usually no treatment is needed. It can remain unchanged for years but can resolve spontaneously. Signs and symptoms Dermatofibromas are hard solitary slow-growing papules (rounded bumps) that appear in a variety of colours, usually brownish to tan. They are often elevated or pedunculated. A dermatofibroma is associated with the dimple sign; by app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Undifferentiated Pleomorphic Sarcoma
Undifferentiated pleomorphic sarcoma (UPS), also termed pleomorphic myofibrosarcoma, high-grade myofibroblastic sarcoma, and high-grade myofibrosarcoma, is characterized by the World Health Organization (WHO), 2020, as a rare, poorly differentiated neoplasm, i.e. an abnormal growth of cells that have an unclear identity and/or cell of origin. WHO classified it as one of the undifferentiated/unclassified sarcomas in the category of tumors of uncertain differentiation. Sarcomas are cancers known or thought to derive from mesenchymal stem cells that typically develop in bone, muscle, fat, blood vessels, lymphatic vessels, tendons, and ligaments. More than 70 sarcoma subtypes have been described. The UPS subtype of these sarcomas consists of tumor cells that are poorly differentiated and may appear as spindle-shaped cells, histiocytes, and giant cells. UPS is considered a diagnosis that defies formal sub-classification after thorough histologic, immunohistochemical, and ultrastructural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malignant Fibrous Histiocytoma
Undifferentiated pleomorphic sarcoma (UPS), also termed pleomorphic myofibrosarcoma, high-grade myofibroblastic sarcoma, and high-grade myofibrosarcoma, is characterized by the World Health Organization (WHO), 2020, as a rare, poorly differentiated neoplasm, i.e. an abnormal growth of cells that have an unclear identity and/or cell of origin. WHO classified it as one of the undifferentiated/unclassified sarcomas in the category of tumors of uncertain differentiation. Sarcomas are cancers known or thought to derive from mesenchymal stem cells that typically develop in bone, muscle, fat, blood vessels, lymphatic vessels, tendons, and ligaments. More than 70 sarcoma subtypes have been described. The UPS subtype of these sarcomas consists of tumor cells that are poorly differentiated and may appear as spindle-shaped cells, histiocytes, and giant cells. UPS is considered a diagnosis that defies formal sub-classification after thorough histologic, immunohistochemical, and ultrastructural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibroblastic/myofibroblastic Tumors
Fibroblastic and myofibroblastic tumors (FMTs) develop from the mesenchymal stem cells which differentiate into fibroblasts (the most common cell type in connective tissue) and/or the myocytes/myoblasts that differentiate into muscle cells. FMTs are a heterogeneous group of soft tissue neoplasms (i.e. abnormal and excessive tissue growths). 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. Myof ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Lineage
Cell lineage denotes the developmental history of a tissue or organ from the fertilized embryo. This is based on the tracking of an organism's cellular ancestry due to the cell divisions and relocation as time progresses, this starts with the originator cells and finishing with a mature cell that can no longer divide. This type of lineage can be studied by marking a cell (with fluorescent molecules or other traceable markers) and following its progeny after cell division. Some organisms, such as ''C. elegans'', have a predetermined pattern of cell progeny and the adult male will always consist of 1031 cells, this is because cell division in ''C. elegans'' is genetically determined and known as eutely. This causes the cell lineage and cell fate to be highly correlated. Other organisms, such as humans, have variable lineages and somatic cell numbers. ''C. elegans'': model organism As one of the first pioneers of cell lineage, in the 1960s Dr. Sydney Brenner first began observing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibroblasts
A fibroblast is a type of biological cell that synthesizes the extracellular matrix and collagen, produces the structural framework ( stroma) for animal tissues, and plays a critical role in wound healing. Fibroblasts are the most common cells of connective tissue in animals. Structure Fibroblasts have a branched cytoplasm surrounding an elliptical, speckled nucleus having two or more nucleoli. Active fibroblasts can be recognized by their abundant rough endoplasmic reticulum. Inactive fibroblasts (called fibrocytes) are smaller, spindle-shaped, and have a reduced amount of rough endoplasmic reticulum. Although disjointed and scattered when they have to cover a large space, fibroblasts, when crowded, often locally align in parallel clusters. Unlike the epithelial cells lining the body structures, fibroblasts do not form flat monolayers and are not restricted by a polarizing attachment to a basal lamina on one side, although they may contribute to basal lamina components in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesenchymal Stem Cells
Mesenchymal stem cells (MSCs) also known as mesenchymal stromal cells or medicinal signaling cells are multipotent stromal cells that can differentiate into a variety of cell types, including osteoblasts (bone cells), chondrocytes (cartilage cells), myocytes (muscle cells) and adipocytes (fat cells which give rise to marrow adipose tissue). Structure Definition While the terms ''mesenchymal stem cell'' (MSC) and ''marrow stromal cell'' have been used interchangeably for many years, neither term is sufficiently descriptive: * Mesenchyme is embryonic connective tissue that is derived from the mesoderm and that differentiates into hematopoietic and connective tissue, whereas MSCs do not differentiate into hematopoietic cells. * Stromal cells are connective tissue cells that form the supportive structure in which the functional cells of the tissue reside. While this is an accurate description for one function of MSCs, the term fails to convey the relatively recently discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoplastic
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists in growing abnormally, even if the original trigger is removed. This abnormal growth usually forms a mass, when it may be called a tumor. ICD-10 classifies neoplasms into four main groups: benign neoplasms, in situ neoplasms, malignant neoplasms, and neoplasms of uncertain or unknown behavior. Malignant neoplasms are also simply known as cancers and are the focus of oncology. Prior to the abnormal growth of tissue, as neoplasia, cells often undergo an abnormal pattern of growth, such as metaplasia or dysplasia. However, metaplasia or dysplasia does not always progress to neoplasia and can occur in other conditions as well. The word is from Ancient Greek 'new' and 'formation, creation'. Types A neoplasm can be benign, potentially ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytogenetic
Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis and meiosis. Techniques used include karyotyping, analysis of G-banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as fluorescent ''in situ'' hybridization (FISH) and comparative genomic hybridization (CGH). History Beginnings Chromosomes were first observed in plant cells by Carl Nägeli in 1842. Their behavior in animal (salamander) cells was described by Walther Flemming, the discoverer of mitosis, in 1882. The name was coined by another German anatomist, von Waldeyer in 1888. The next stage took place after the development of genetics in the early 20th century, when it was appreciated that the set of chromosomes (the karyotype) was the carrier of the genes. Levitsky seems to have been t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Fibroblasts")
