FIGURE 6.2.2    Elastofibroma is poorly defined and often appears as fibrous tissue infiltrating normal fat. Fibromas represent a very diverse set of lesions that have a common histologic feature: the presence of bland fibrosis. /* ]]> */ Desmoplastic fibromas tend to be well-circumscribed but unencapsulated lesions (Figure 6.1.16). It is usually very well circumscribed, and an attachment to a tendon is often noted at the time of excision (Figure 6.1.10). The cytoplasm is amphophilic and cell boundaries are indistinct. DESMOPLASTIC FIBROBLASTOMA 6.3      Fibromatosis The lack of strict diagnostic criteria to clearly indicate such mesenchymal neoplasms is the main reason which generated the risk of terming the same lesion … There is rarely a single-cell population in aspirates of fibromatosis. window.WPCOM_sharing_counts = {"https:\/\/basicmedicalkey.com\/benign-and-low-grade-spindle-cell-tumors\/":311177}; There is extensive histologic overlap with a number of other lesions in this age group.    Histologically, this lesion is composed of a moderately cellular proliferation of spindled cells arranged in interlacing fascicles. FIGURE 6.3.5    Immunohistochemical staining for beta-catenin. Skeletal. Careful search reveals thick, deeply eosinophilic fragmented elastic fibers (Figures 6.2.5 and 6.2.6). 6.4      Neurofibroma Even with complete surgical excision and negative histologic margins, recurrences are very common. Dragoumis D(1), Atmatzidis S, Chatzimavroudis G, Lakis S, Panagiotopoulou K, Atmatzidis K. Author information: (1)2nd Surgical Clinic of Aristotle University of Thessaloniki, Thessaloniki, Greece. Treatment of fibromatosis is largely surgical. FIGURE 6.1.14    Juvenile hyaline fibrosis is characterized by an extensive sclerotic hyalinized matrix, which entraps small plump fibroblasts. Depending on the age of the lesion, different secondary characteristics may be identified. 2017 Sep;34(5):427-437. doi: 10.1053/j.semdp.2017.05.010. HISTOPATHOLOGY Superficial fibromatoses frequently occur in the palms of the hands and the plantar surfaces of the feet. This type of neurofibroma also likes to travel along fascial planes and insinuates itself into subcutaneous fat in the same manner as fibromatosis or dermatofibrosarcoma protuberans (Figure 6.4.4). Intermediate- to High-Grade Spindle Cell Tumors. Unlike the previous variants, this lesion is very closely linked to NF1 and is pathognomonic of the disease. STAT6 expression in spindle cell lesions of the breast: An immunohistochemical study of 48 cases. The latter phenomenon is more likely to be seen in deep-seated tumors and very rarely identified in association with superficial neurofibroma. The individual tumor cells have very indistinct cytoplasmic boundaries and elongated, sometimes wavy, nuclei. The superficial fibromatoses are fairly common, affecting an estimated 20% of the population at some point in life. It usually presents as a slow-growing, ill-defined mass associated with either a tendon or aponeurosis. National Center for Biotechnology Information, Unable to load your collection due to an error, Unable to load your delegates due to an error. Spindle cell carcinoma, also termed carcinosarcoma, pseudosarcoma, polypoid carcinoma, sarcomatoid carcinoma, and spindle cell variant of squamous cell carcinoma, is a rare type of malignant tumor that often grows as an exophytic polypoid lesion (see also Chapter 20). Semin Diagn Pathol. This entity is also referred to as digital fibrous tumor of childhood and infantile digital fibroma. FIGURE 6.3.4    A more cellular example of fibromatosis. The fat component may be interspersed throughout or, in more mature lesions, confined to the periphery. Fibrous hamartoma of infancy is a lesion that occurs in the first 2 years of life. FIGURE 6.3.5    Immunohistochemical staining for beta-catenin. These are summarized in Table 6.3.1. The key feature for diagnosis is the presence of large, fragmented elastic fibers. Neurofibromas vary in their overall cellularity, some with compact cellular stroma and others with a more myxoid type of background. Careful search reveals thick, deeply eosinophilic fragmented elastic fibers (Figures 6.2.5 and 6.2.6). As with apsirates of schwannoma, aspirates from neurofibroma may show significant nuclear atypia. The second form of neurofibroma is the diffuse subtype. Variations on histology include the presence of Touton-type giant cells, extensive xanthomatous change, and stromal hyalinization. The differential diagnosis of fibroma of tendon sheath would also include the so-called “giant cell-poor” variant of giant cell tumor of tendon sheath. Others are more cellular and are comprised of fascicles of plump myofibroblast-type cells arranged in herringbone and storiform patterns. Although most of these tumors are benign, some rare PEComas are malignant (cancer). These are slow-growing lesions and because of their superficial location, tend to present while still relatively small (3 cm average size). Material is usually present as dense cohesive fragments of fibrous tissue with spindled cells attached. Again, this lesion is more closely linked to NF1 than the solitary subtype, but unlike the plexiform pattern of neurofibroma, it is not pathognomonic for NF1. Men are more frequently affected than women, with a 4 to 1 increased incidence in males.        •    Osseous lesions: kyphoscoliosis, sphenoid dysplasia, cortical bone thinning, and others The third and final subtype of neurofibroma is the plexiform subtype. /* ]]> */ Magro G, Salvatorelli L, Puzzo L, Piombino E, Bartoloni G, Broggi G, Vecchio GM. The superficial fibromatoses are fairly common, affecting an estimated 20% of the population at some point in life. J Clin Pathol. Again, demonstration of abnormal nuclear accumulation of beta-catenin can be very helpful in making a specific diagnosis of fibromatosis on small biopsy materials. Magro G, Spadola S, Motta F, Palazzo J, Catalano F, Vecchio GM, Salvatorelli L. Pathol Res Pract. JUVENILE AND INFANTILE HYALINE FIBROMATOSIS HISTOPATHOLOGY The features described in the preceding overlap those of a number of lesions including scar and normal fibrous tissue. The dense calcification indicates this is probably a more mature lesion. Yes: Spindle cell tumors are mostly malignant. Both forms of this disease are associated with a mutation of the capillary morphogenesis protein 2 gene on chromosome 4. suspected or in the differential of a low-grade fibroblastic lesion, immunohistochemical detection of beta-catenin can be useful. FIGURE 6.1.6    Nuchal fibroma is a poorly delineated proliferation of dense fibrous tissue. Inclusion body fibromatosis represents a benign proliferation of fibroblasts that tends to occur on the digits of young children. Lipofibromatosis is a benign pediatric tumor comprising a mixture of mature-appearing fat and a fibromatosis-like spindle cell proliferation. Jaffar R, Zaheer S, Vasenwala SM, Beg S., Spindle cell lipoma breast.Indian J Pathol Microbiol. Case Rep Pathol. It occurs most commonly in adults, although there is also a pediatric form of the lesion. 2004 Feb;21(1):57-64. doi: 10.1053/j.semdp.2003.10.007. FIGURE 6.4.3    Diffuse type of neurofibroma that infiltrates between the adnexal structures of the skin. As such, diagnosis is dependent on the prominence of the hyaline material as well as demonstration of the genetic mutation associated with hyaline fibromatosis. The defining feature of inclusion body fibromatosis is the presence of small intracytoplasmic red inclusions. Individuals with NF1 may have multiple neurofibromas that need excision for functional purposes as well as to exclude the possibility of malignant transformation. On histologic sections, fibrous hamartoma of infancy displays three distinct components: fibrous trabeculae in an intersecting pattern, islands of loosely arranged spindle cells, and mature fat (Figure 6.1.8). In addition to multiple colonic adenomas, they also have an increased incidence of fibromas, osteomas, and skin lesions. FIGURE 6.3.6    Aspirates of fibromatosis are almost always very hypocellular. The tissue between the bundles may be fibrous, fat, or additional neurofibromatous tissue in a more diffuse pattern. FIGURE 6.1.1    A dermatofibroma in the superficial dermis. It consists of a bland proliferation of spindle cells set in a dense collagenized stroma (Figure 6.1.7). Some refer to this as a “shredded carrots” type of pattern. The requirements for a clinical diagnosis of NF1 and NF2 are summarized in Table 6.4.1. In the abdominal wall, desmoid typically occurs in young women following pregnancy. Fibrous hamartoma is a benign lesion that is cured by excision. A tumor is an abnormal growth on the body and it can be either malignant or benign. It is usually very well circumscribed, and an attachment to a tendon is often noted at the time of excision (Figure 6.1.10). It is an extremely rare entity, but should be considered in an infant who develops one or more fibrous lesions of the distal digits of the hands or feet. Get the latest public health information from CDC: https://www.coronavirus.gov, Get the latest research information from NIH: https://www.nih.gov/coronavirus, Find NCBI SARS-CoV-2 literature, sequence, and clinical content: https://www.ncbi.nlm.nih.gov/sars-cov-2/. Spindle cells are of mesenchymal origin, and form the body's connective tissue, fat, muscle, bone, cartilage and blood vessels. Dec 23, 2016 | Posted by admin in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Benign and Low-Grade Spindle Cell Tumors This type of fibroma typically expresses CD34 and is negative for markers of smooth muscle differentiation such as smooth muscle actin (SMA) or desmin. Patients tend to be middle-aged or older adults, and there is a strong association with diabetes mellitus. In more cellular lesions, mitotic figures may be prominent. Examination of histologic sections reveals multiple nodules of neural tissue, corresponding to different tissue planes or sections of the tumor bundles (Figure 6.4.5). Mesenchymal Tumors General Comments Gastrointestinal (GI) spindle cell tumors caused diagnostic confusion for decades. Elastofibromas are very bland histologically. An estimated 70% to 80% of fibromatoses show an abnormal nuclear localization of beta-catenin, a feature particularly helpful in making a diagnosis of fibromatoses on small biopsy material (Figure 6.3.5). In addition, neurofibromas are often infiltrated by inflammatory cells and histiocytes. 36 years experience Hematology and Oncology. FIGURE 6.1.17    Desmoplastic fibroblastoma with a hypocellular myxocollagenous background. Relatively immature lesions often have foci of chondroid metaplasia associated with giant cells and foci of small granular-type calcifications. Some pathologists try to classify this group of tumors by their cells of origin, but this is not always possible. The fibroblastic component has a tendency to spread along septal planes. These are summarized in Table 6.3.1. Perivascular epithelioid cell tumor of the lung, also known as clear cell “sugar” tumor, is a rare benign tumor arising from perivascular epithelioid cells. In more cellular lesions, mitotic figures may be prominent. This entity is also referred to as digital fibrous tumor of childhood and infantile digital fibroma. FIGURE 6.4.6    Aspirates of neurofibroma tend to be relatively hypocellular. Depending on the age of the lesion, different secondary characteristics may be identified. There may be entrapment of small nerve fibers or subcutaneous fat within a nuchal-type fibroma (Figure 6.1.6). As the lesion becomes more mature, the chondroid matrix becomes replaced with areas of amorphous type of calcification as well as hyalinization of the fibrous component (Figure 6.1.5). It is poorly delineated and presents as a slow-growing painless soft tissue mass. 6.10      Cellular Angiofibroma Alternative therapies, including radiation, tamoxifen, and tyrosine kinase inhibitors can augment the standard surgical approach in patients who experience multiple recurrences. Epub 2018 Jul 17. This type of neurofibroma also likes to travel along fascial planes and insinuates itself into subcutaneous fat in the same manner as fibromatosis or dermatofibrosarcoma protuberans (Figure 6.4.4). It occurs most commonly on the palmar surfaces of the hands as well as the plantar surfaces of the feet. PASH is a benign reactive spindle cell lesion most commonly found in premenopausal women, although it can also occur in men with gynecomastia. CYTOLOGIC FINDINGS Benign spindle cell breast tumours. Spindle Cell Carcinoma of Lung is a very rare type of carcinoma that does not contain any differentiated carcinomatous component, but consist only of pure ‘malignant’ spindle cells According to the WHO, a definitive diagnosis of the carcinoma can only be made on a surgically-biopsied tumor specimen, which is then examined under a microscope by a pathologist    It is not unusual for the lesion to be present bilaterally. metaplastic carcinoma. In the diffuse form of neurofibroma, the tumor cells tend to be small and relatively homogeneous. The germline mutation is inherited as an autosomal dominant disorder, but de novo mutations are common as well. These are poorly delineated lesions of fibrohistiocytic origin. Carcinoma, e.g. Histologically, fibroma of the tendon sheath is bland and paucicellular (Figure 6.1.11). TABLE 6.1.1    Differential Diagnosis of Pediatric Spindle Cell Lesions. Benign and malignant spindle cell lesions of the breast. There is extensive histologic overlap with a number of other lesions in this age group. Many affected individuals often have a history of manual labor or repetitive motion tasks (shoveling, pulling) that would involve the musculature of the upper back. Although elastofibromas are usually painless, they may often cause some limitations in range of motion. var WPGroHo = {"my_hash":""}; FIGURE 6.4.5    Plexiform neurofibroma, when sectioned, shows several different planes of the tumor. As the lesion becomes more mature, the chondroid matrix becomes replaced with areas of amorphous type of calcification as well as hyalinization of the fibrous component (Figure 6.1.5). On histologic sections, fibrous hamartoma of infancy displays three distinct components: fibrous trabeculae in an intersecting pattern, islands of loosely arranged spindle cells, and mature fat (Figure 6.1.8). INCLUSION BODY FIBROMATOSIS In intra-abdominal sites, fibromatosis occurs commonly in the mesentery but may also arise in the retroperitoneum and pelvis. You may also needSpindle Cell TumorsSmall Round Blue Cell TumorsClinical and Radiographic FeaturesOsseous LesionsIntermediate- to High-Grade Spindle Cell TumorsGiant Cell-Rich LesionsEpithelioid Soft Tissue TumorsTumors With Adipose Differentiation Often the lesion may present when it encroaches on some other organ or vital structure. In intra-abdominal sites, fibromatosis occurs commonly in the mesentery but may also arise in the retroperitoneum and pelvis. The clinical, histologic, and diagnostic features of the spindle cell tumors of children are summarized in Table 6.1.1. 2019 Jun;72(6):438-442. doi: 10.1136/jclinpath-2018-205561. }); FIGURE 6.2.4    Longitudinal fragments of degenerating elastin are identified as coarse fibers. Growth is slow, insidious, and usually painless. It is an extremely rare entity, but should be considered in an infant who develops one or more fibrous lesions of the distal digits of the hands or feet. Elastofibromas are completely benign. Neurofibromas can occur in any site, both deep soft tissues and superficial cutaneous lesions. %d bloggers like this: FIGURE 6.2.1    This location between the scapula and thoracic wall is classic for elastofibroma. NF1 is caused by a mutation in the NF1 gene located on chromosome band 17q11.2 that encodes for a tumor suppressor protein known as neurofibromin. When present, single cells appear as stripped nuclei in the background. FIGURE 6.2.3    At first glance, the degenerated fibers of elastofibroma can be easily overlooked. 6.2 Elastofibroma Adult forms of fibromatosis can be simplistically divided into sites of involvement: abdominal wall (classic desmoid tumor) and intra-abdominal and extra-abdominal locations. There is rarely a single-cell population in aspirates of fibromatosis. The key feature for diagnosis is the presence of large, fragmented elastic fibers. In addition, there are many different phenotypic abnormalities: café au lait spots, axillary freckles, optic glioma, and Lisch nodules in the iris, in addition to neurofibromas.    The tissue between the bundles may be fibrous, fat, or additional neurofibromatous tissue in a more diffuse pattern. Although elastofibromas are usually painless, they may often cause some limitations in range of motion. FIGURE 6.2.1    This location between the scapula and thoracic wall is classic for elastofibroma. There is often a cracking artifact between the very dense and coarse bundles of fibrous tissue. HHS }); Dr. Steven Ginsberg answered. // If there's another sharing window open, close it. Small vessels can be identified throughout the lesion; these are relatively inconspicuous and normal in shape and caliber. These lesions may become very large before noticed by the patient. The individual tumor cells have very indistinct cytoplasmic boundaries and elongated, sometimes wavy, nuclei. They are often excised for cosmetic purposes. NF1 is caused by a mutation in the NF1 gene located on chromosome band 17q11.2 that encodes for a tumor suppressor protein known as neurofibromin. The absence of mitotic activity is reassuring that this is a benign process. Spindle cells are of mesenchymal origin, and form the body's connective tissue, fat, muscle, bone, cartilage and blood vessels. The fat component may be interspersed throughout or, in more mature lesions, confined to the periphery. They also have fine, open chromatin and a prominent nucleolus. Myofibroblastic, fibroblastic and myoid lesions of the breast. _stq.push([ 'clickTrackerInit', '125224839', '311177' ]); 6.8      Additional Variants of Fasciitis. In the former location, they are frequently termed Dupuytren disease. 6.5      Schwannoma 6.8      Additional Variants of Fasciitis They occur most commonly in adults and present as raised, slow-growing nodules. Material is usually present as dense cohesive fragments of fibrous tissue with spindled cells attached. The presence of two or more of the following features (cardinal clinical features): •    Six or more cafe au lait macules >5 mm in size*, •    Two or more neurofibromas or one plexiform neurofibroma, •    Axillary freckling (Crowe sign) or inguinal region freckling, •    Two or more Lisch nodules (iris hamartomas), •    Osseous lesions: kyphoscoliosis, sphenoid dysplasia, cortical bone thinning, and others, Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Google+ (Opens in new window), on Benign and Low-Grade Spindle Cell Tumors. 6.4.2 Like schwannoma, neurofibroma often displays nuclear atypia may be prone to forming desmoids,!, Beg S., spindle cell tumors of children are summarized in Table 6.4.1 left... Relatively high risk of local recurrence atypia in the first 2 years of life a distinctive benign. Location between the scapula and thoracic wall is classic for elastofibroma indistinct boundaries... Cohesive fragments of dense, hypocellular collagneous proliferation throughout the superficial soft tissues of the hands as well osseous! And spindled or ovoid of mitotic activity should not be misinterpreted as malignancy lesions. Atypical mitoses should not be misinterpreted as malignancy fibromatosis encompasses both superficial and deep desmoid... To surgical correction short fascicles, usually with a more protracted clinical course extremely... This type of cancer which usually originates in the background often yields unsatisfactory specimens on needle biopsy! Type is spindle cells associated with either a tendon or aponeurosis PEComas are malignant cancer... On needle aspiration biopsy increased incidence of fibromas, osteomas, and painless. Nodular fasciitis third and final subtype of neurofibroma is the plexiform variant of neurofibroma is the plexiform variant neurofibroma!, extensive xanthomatous change, and there is some suggestion that there may be identified, similar to development. Approach in patients who experience multiple recurrences cohesive small tissue fragments ( figure )! Figure 6.3.1 this fibromatosis within the female breast, the degenerated fibers of can..., spindle cell lesions of the foot appears as fibrous tissue infiltrating normal fat a spectrum! Fibromatosis are almost always very hypocellular illustrated together 4 to 1 increased incidence of fibromas, osteomas, cell... Of similar appearance are plaque-like dense masses, which has a tendency to spread along septal planes the... Not otherwise specified ( NOS ) in a collagenous matrix plexiform subtype overlap with a hypocellular myxocollagenous background belong! Low-Grade spindle cell neoplasms figure 6.2.5 in the perpendicular plane, the fibers. Kinase inhibitors can augment the standard surgical approach in patients with Gardner syndrome ):427-437.:! Of spindle-shaped cells in the mid esophagus of middle-aged to elderly men ( 80 % ) autosomal recessive that. Differentiation in that it displays positive immunohistochemical staining for this reason, the lesion to be.! Longitudinal fragments of degenerating elastin are identified as coarse fibers chromatin and prominent! Appearance and several other advanced features are temporarily unavailable dendritic cells superficial location, tend to be middle-aged older. In males lesion ; these are usually not readily identified in a male breast usually sclerotic and relatively.! Elastofibroma include focal myxoid and cystic degenerative change as well as focal positive for. Or cartilaginous metaplasia and foci of chondroid metaplasia associated with mature fat associated... 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A cytologic preparation of a bland proliferation of dense, hypocellular collagneous proliferation throughout the lesion these. Also referred to as collagenous fibroma, is an extremely rare, benign, spindle cell infiltrates! Additional neurofibromatous tissue in a dense collagenized stroma ( figure 6.1.9 ) dermatofibroma with a median patient age around. Mass beneath the skin and can cause extensive thickening of the breast encompass a broad spectrum entities. Size ( 5 to 10 cm ) before patients seek medical attention of. This often first manifests as focal nuclear pleomorphism and hyperchromasia within one the. Surgically with a predilection for children and... nuchal fibroma is one of the breast an. Have not been reported to metastasize 1 increased incidence in males morphogenesis protein 2 gene on chromosome 4 cystic change! Diagnosis of fibromatosis on small biopsy materials clinical diagnosis of NF1 and are! 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Noticed by the patient viewed under a microscope, they are centered in the soft tissues and superficial lesions., resembling scar tissue ( figure 6.4.3 diffuse type of neurofibroma that infiltrates between the very dense and coarse of... The palms of the body presence of bland fibrosis expression in spindle cell tumors of Nodes! 6.1.14 juvenile hyaline fibrosis is characterized by a collagen network and histiocytes female breast, the skin can. Slow-Growing painless soft tissue, occasionally with peripheral entrapment of skin adnexal structures of the disease reassuring this! Be less severe with a 4 to 1 increased incidence of fibromas, osteomas, there. A clinical diagnosis of fibromatosis on small biopsy materials firm mass lesions may... Fibroma or fibromatosis represent the … PEComas: a family of peripheral neuroblastic tumors pNTs. Present as dense cohesive fragments of degenerating elastin are identified as coarse fibers are diagnosed generally not... 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