Fibroblastic and myofibroblastic tumors

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Fibroblastic and myofibroblastic tumors
Specialty Pathology, Dermatology, General surgery, Oncology, Surgical oncology
Types Benign, locally invasive, rarely metastasizing, malignant

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. [1] 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. [2] The World Health Organization further classified FMTs into four tumor forms based on their varying levels of aggressiveness: benign, intermediate (locally aggressive), intermediate (rarely metastasizing), and malignant. [1]

Benign FMTs

Intermediate (locally aggressive) FMTs

Intermediate (rarely metastasizing) FMTs

Malignant FMTs

See also

Plexiform angiomyxoid myofibroblastic tumor

Related Research Articles

<span class="mw-page-title-main">Fibroma</span> Medical condition

Fibromas are benign tumors that are composed of fibrous or connective tissue. They can grow in all organs, arising from mesenchyme tissue. The term "fibroblastic" or "fibromatous" is used to describe tumors of the fibrous connective tissue. When the term fibroma is used without modifier, it is usually considered benign, with the term fibrosarcoma reserved for malignant tumors.

<span class="mw-page-title-main">Fibrosarcoma</span> Medical condition

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.

A histiocytoma is a tumour consisting of histiocytes. Histiocytes are 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.

<span class="mw-page-title-main">Nodular fasciitis</span> Medical condition

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.

<span class="mw-page-title-main">Aggressive fibromatosis</span> Medical condition

Aggressive fibromatosis or desmoid tumor is a rare condition. Desmoid tumors are a type of fibromatosis and related to sarcoma, though without the ability to spread throughout the body (metastasize). The tumors arise from cells called fibroblasts, which are found throughout the body and provide structural support, protection to the vital organs, and play a critical role in wound healing. These tumors tend to occur in women in their thirties, but can occur in anyone at any age. They can be either relatively slow-growing or malignant. However, aggressive fibromatosis is locally aggressive and can cause life-threatening problems or even death when the tumors compress vital organs such as intestines, kidneys, lungs, blood vessels, or nerves. The condition is rarely fatal. Most cases are sporadic, but some are associated with familial adenomatous polyposis (FAP). Approximately 10% of individuals with Gardner's syndrome, a type of FAP with extracolonic features, have desmoid tumors.

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.

<span class="mw-page-title-main">Angiofibroma</span> Medical condition

Angiofibroma (AGF) is a descriptive term for a wide range of benign skin or mucous membrane lesions in which individuals have:

  1. benign papules, i.e. pinhead-sized elevations that lack visible evidence of containing fluid;
  2. nodules, i.e. small firm lumps usually >0.1 cm in diameter; and/or
  3. tumors, i.e. masses often regarded as ~0.8 cm or larger.

Infantile digital fibromatosis (IDF), also termed inclusion body fibromatosis, Reye tumor, or Reye's tumor, usually occurs as a single, small, asymptomatic, nodule in the dermis on a finger or toe of infants and young children. IMF is a rare disorder with approximately 200 cases reported in the medical literature as of 2021. The World Health Organization in 2020 classified these nodules as a specific benign tumor type in the category of fibroblastic and myofibroblastic tumors. IDF was first described by the Australian pathologist, Douglas Reye, in 1965.

Fibrous hamartoma of infancy (FHI) is a rare, typically painless, benign tumor that develops in the subcutaneous tissues of the axilla, arms, external genitalia, or, less commonly, various other areas. It is diagnosed in children who are usually less than 2 years old or, in up to 20% of cases, develops in utero and is diagnosed in an infant at birth.

<span class="mw-page-title-main">Fibroma of tendon sheath</span> Medical condition

Fibroma of tendon sheath is a benign tumor that presents as a small subcutaneous nodule that slowly increases in size. The tumors often have a multinodular growth pattern, with individual nodules being composed of bland, slender, spindle-shaped cells (myofibroblasts) in a dense, fibrous matrix.” A common microscopic finding is the presence of elongated, slit-like blood vessels. The lesions nearly always arise in the distal portions of the extremities. They often occur on the fingers, hands, toes, or feet. Although they are benign, they may recur in up to 40% of cases.

<span class="mw-page-title-main">Low-grade fibromyxoid sarcoma</span> Medical condition

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.

<span class="mw-page-title-main">Mammary-type myofibroblastoma</span> Medical condition

Mammary-type myofibroblastoma (MFB), also named mammary and extramammary myofibroblastoma, was first termed myofibrolastoma of the breast, or, more simply, either mammary myofibroblastoma (MMFB) or just myofibroblastoma. The change in this terminology occurred because the initial 1987 study and many subsequent studies found this tumor only in breast tissue. However, a 2001 study followed by numerous reports found tumors with the microscopic histopathology and other key features of mammary MFB in a wide range of organs and tissues. Further complicating the issue, early studies on MFB classified it as one of various types of spindle cell tumors that, except for MFB, were ill-defined. These other tumors, which have often been named interchangeably in different reports, are: myelofibroblastoma, benign spindle cell tumor, fibroma, spindle cell lipoma, myogenic stromal tumor, and solitary stromal tumor. Finally, studies suggest that spindle cell lipoma and cellular angiofibroma are variants of MFB. Here, the latter two tumors are tentatively classified as MFB variants but otherwise MFB is described as it is more strictly defined in most recent publications. The World Health Organization in 2020 classified mammary type myofibroblastoma tumors and myofibroblastoma tumors as separate tumor forms within the category of fibroblastic and myofibroblastic tumors.

Acral myxoinflammatory fibroblastic sarcoma (AMSF), also termed myxoinflammatory fibroblastic sarcoma (MSF), is a rare, low-grade, soft tissue tumor that the World Health Organization (2020) classified as in the category of rarely metastasizing fibroblastic and myofibroblastic tumors. It is a locally aggressive neoplasm that often recurs at the site of its surgical removal. However, it usually grows slowly and in only 1–2% of cases spreads to distant tissues.

<span class="mw-page-title-main">Proliferative fasciitis and proliferative myositis</span> Medical condition

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.

Lipofibromatosis (LPF) is an extremely rare soft tissue tumor which was first clearly described in 2000 by Fetsch et al as a strictly pediatric, locally invasive, and often recurrent tumor. It is nonetheless a non-metastasizing, i.e. benign, tumor. While even the more recent literature has sometimes regarded LPF as a strictly childhood disorder, rare cases of LPF has been diagnosed in adults. The diagnosis of lipofibromatosis should not be automatically discarded because of an individual's age.

Lipofibromatosis-like neural tumor (LPF-NT) is an extremely rare soft tissue tumor first described by Agaram et al in 2016. As of mid-2021, at least 39 cases of LPF-NT have been reported in the literature. LPF-NT tumors have several features that resemble lipofibromatosis (LPF) tumors, malignant peripheral nerve sheath tumors, spindle cell sarcomas, low-grade neural tumors, peripheral nerve sheath tumors, and other less clearly defined tumors; Prior to the Agaram at al report, LPF-NTs were likely diagnosed as variants or atypical forms of these tumors. The analyses of Agaram at al and subsequent studies uncovered critical differences between LPF-NT and the other tumor forms which suggest that it is a distinct tumor entity differing not only from lipofibromatosis but also the other tumor forms.

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.

Gardner fibroma (GF) is a benign fibroblastic tumor. GF tumors typically develop in the dermis and adjacent subcutaneous tissue lying just below the dermis. These tumors typically occur on the back, abdomen, and other superficial sites but in rare cases have been diagnoses in internal sites such as the retroperitoneum and around the large blood vessels in the upper thoracic cavity. The World Health Organization, 2020, classified Gardner fibroma as a benign tumor in the category of fibroblastic and myofibroblastic tumors.

References

  1. 1 2 Sbaraglia M, Bellan E, Dei Tos AP (April 2021). "The 2020 WHO Classification of Soft Tissue Tumours: news and perspectives". Pathologica. 113 (2): 70–84. doi:10.32074/1591-951X-213. PMC   8167394 . PMID   33179614.
  2. Slack JC, Bründler MA, Nohr E, McIntyre JB, Kurek KC (May 2021). "Molecular Alterations in Pediatric Fibroblastic/Myofibroblastic Tumors: An Appraisal of a Next Generation Sequencing Assay in a Retrospective Single Centre Study". Pediatric and Developmental Pathology. 24 (5): 405–421. doi:10.1177/10935266211015558. PMID   33970051. S2CID   234348021.
  3. 1 2 3 Nakayama S, Nishio J, Aoki M, Koga K, Nabeshima K, Yamamoto T (2021). "Ubiquitin-specific Peptidase 6 (USP6)-associated Fibroblastic/Myofibroblastic Tumors: Evolving Concepts". Cancer Genomics & Proteomics. 18 (2): 93–101. doi:10.21873/cgp.20244. PMC   7943209 . PMID   33608306.
  4. Makise N, Mori T, Motoi T, Shibahara J, Ushiku T, Yoshida A (May 2021). "Recurrent FOS rearrangement in proliferative fasciitis/proliferative myositis". Modern Pathology. 34 (5): 942–950. doi: 10.1038/s41379-020-00725-2 . PMID   33318581. S2CID   228627775.
  5. Kuyumcu G, Zhang Y, Ilaslan H (December 2019). "Case 272: Decubital Ischemic Fasciitis". Radiology. 293 (3): 721–724. doi:10.1148/radiol.2019171255. PMID   31751192. S2CID   208227281.
  6. Fukunaga M (September 2001). "Atypical decubital fibroplasia with unusual histology". APMIS. 109 (9): 631–5. doi:10.1034/j.1600-0463.2001.d01-185.x. PMID   11878717. S2CID   29499215.
  7. 1 2 Martos-Cabrera L, Sampedro-Ruiz R, Pérez-González YC, Mentzel T, Llamas-Velasco M (June 2021). "Fibrous Hamartoma of Infancy: A Series of 21 Cases and Review of the Literature". Actas Dermo-sifiliograficas. 112 (6): 520–527. doi: 10.1016/j.adengl.2021.03.010 . PMID   34088477.
  8. Durnford L, Patel MS, Khamar R, Khurram R (April 2021). "Bilateral sternocleidomastoid pseudotumors-a case report and literature review". Radiology Case Reports. 16 (4): 964–967. doi:10.1016/j.radcr.2021.02.001. PMC   7897923 . PMID   33664922.
  9. Braizat O, Badran S, Hammouda A (October 2020). "Juvenile Hyaline Fibromatosis: Literature Review and a Case Treated With Surgical Excision and Corticosteroid". Cureus. 12 (10): e10823. doi: 10.7759/cureus.10823 . PMC   7645300 . PMID   33173631.
  10. Agnihotri MA, Sathe PA (2021). "Inclusion body fibromatosis - A report of four cases and review of literature". Journal of Postgraduate Medicine. 67 (1): 24–26. doi: 10.4103/jpgm.JPGM_774_20 . PMC   8098864 . PMID   33565473.
  11. Adegoke OO, Ajao AE, Ano-Edward GH (December 2020). "Congenital infantile digital fibromatosis: a case report and review of the literature". African Health Sciences. 20 (4): 1865–1869. doi:10.4314/ahs.v20i4.42. PMC   8351811 . PMID   34394250.
  12. Pižem J, Matjašič A, Zupan A, Luzar B, Šekoranja D, Dimnik K (June 2021). "Fibroma of tendon sheath is defined by a USP6 gene fusion-morphologic and molecular reappraisal of the entity". Modern Pathology. 34 (10): 1876–1888. doi: 10.1038/s41379-021-00836-4 . PMID   34088995. S2CID   235327044.
  13. Nakayama S, Nishio J, Aoki M, Nabeshima K, Yamamoto T (2021). "An Update on Clinicopathological, Imaging and Genetic Features of Desmoplastic Fibroblastoma (Collagenous Fibroma)". In Vivo (Athens, Greece). 35 (1): 69–73. doi:10.21873/invivo.12233. ISSN   0258-851X. PMC   7880796 . PMID   33402451.
  14. 1 2 Howitt BE, Fletcher CD (March 2016). "Mammary-type Myofibroblastoma: Clinicopathologic Characterization in a Series of 143 Cases". The American Journal of Surgical Pathology. 40 (3): 361–7. doi:10.1097/PAS.0000000000000540. PMID   26523539. S2CID   45911598.
  15. 1 2 3 Libbrecht S, Van Dorpe J, Creytens D (March 2021). "The Rapidly Expanding Group of RB1-Deleted Soft Tissue Tumors: An Updated Review". Diagnostics (Basel, Switzerland). 11 (3): 430. doi: 10.3390/diagnostics11030430 . PMC   8000249 . PMID   33802620.
  16. John I, Fritchie KJ (January 2020). "What is new in pericytomatous, myoid, and myofibroblastic tumors?". Virchows Archiv. 476 (1): 57–64. doi:10.1007/s00428-019-02700-y. PMID   31705190. S2CID   207941071.
  17. 1 2 Foot O, Hallin M, Jones RL, Sumathi VP, Thway K (April 2021). "EWSR1-SMAD3-Positive Fibroblastic Tumor". International Journal of Surgical Pathology. 29 (2): 179–181. doi:10.1177/1066896920938124. PMID   32615834. S2CID   220326585.
  18. Dermawan JK, Ko JS, Billings SD (June 2021). "Update on Cutaneous Soft Tissue Tumors". Surgical Pathology Clinics. 14 (2): 195–207. doi:10.1016/j.path.2021.03.002. PMID   34023100. S2CID   235169042.
  19. Habeeb O, Korty KE, Azzato EM, Astbury C, Farkas DH, Ko JS, Billings SD (February 2021). "EWSR1-SMAD3 rearranged fibroblastic tumor: Case series and review". Journal of Cutaneous Pathology. 48 (2): 255–262. doi:10.1111/cup.13870. PMID   32901982. S2CID   221572166.
  20. Chapel DB, Cipriani NA, Bennett JA (January 2021). "Mesenchymal lesions of the vulva". Seminars in Diagnostic Pathology. 38 (1): 85–98. doi:10.1053/j.semdp.2020.09.003. PMID   32958293. S2CID   221842800.
  21. Purkait S, Mitra S, Adhya AK, Sethy M, Mishra TS (July 2021). "Cytology of angiofibroma of soft tissue of the inguinal region". Cytopathology. 33 (2): 276–280. doi:10.1111/cyt.13039. PMID   34273199. S2CID   236034719.
  22. Kostakis ID, Feretis T, Damaskos C, Garmpis N, Liapis G, Pateras I, Garmpi A, Georgakopoulou VE, Antoniou EA (2020). "Nuchal-type Fibroma: Single-Center Experience and Systematic Literature Review". In Vivo (Athens, Greece). 34 (5): 2217–2223. doi:10.21873/invivo.12032. PMC   7652458 . PMID   32871744.
  23. Baranov E, Hornick JL (March 2020). "Soft Tissue Special Issue: Fibroblastic and Myofibroblastic Neoplasms of the Head and Neck". Head and Neck Pathology. 14 (1): 43–58. doi:10.1007/s12105-019-01104-3. PMC   7021862 . PMID   31950474.
  24. Coffin CM, Hornick JL, Zhou H, Fletcher CD (March 2007). "Gardner fibroma: a clinicopathologic and immunohistochemical analysis of 45 patients with 57 fibromas". The American Journal of Surgical Pathology. 31 (3): 410–6. doi:10.1097/01.pas.0000213348.65014.0a. PMID   17325483. S2CID   25831659.
  25. Stewart BD, Nascimento AF (July 2021). "Palmar and plantar fibromatosis: a review". Journal of Pathology and Translational Medicine. 55 (4): 265–270. doi:10.4132/jptm.2021.06.14. PMC   8353138 . PMID   34225446.
  26. Burney IA, Kakaria AK, Al-Jahdhami S (May 2021). "Complete Response to Sorafenib in Locally Recurrent Unresectable Aggressive Fibromatosis". Sultan Qaboos University Medical Journal. 21 (2): e327–e328. doi:10.18295/squmj.2021.21.02.027. PMC   8219336 . PMID   34221486.
  27. Malik F, Santiago T, Newman S, McCarville B, Pappo AS, Clay MR (June 2020). "An addition to the evolving spectrum of lipofibromatosis and lipofibromatosis-like neural tumor: Molecular findings in an unusual phenotype aid in accurate classification". Pathology, Research and Practice. 216 (6): 152942. doi:10.1016/j.prp.2020.152942. PMID   32299759. S2CID   215803522.
  28. "Giant cell fibroblastoma"..
  29. 1 2 Xiong JX, Cai T, Hu L, Chen XL, Huang K, Chen AJ, Wang P (July 2021). "Risk factors related to postoperative recurrence of dermatofibrosarcoma protuberans: A retrospective study and literature review". World Journal of Clinical Cases. 9 (20): 5442–5452. doi: 10.12998/wjcc.v9.i20.5442 . ISSN   2307-8960. PMC   8281415 . PMID   34307598.
  30. Zhang J, Liu J, Zhang Z, Tian B (2021). "Solitary Fibrous Tumors of the Chest: An Analysis of Fifty Patients". Frontiers in Oncology. 11: 697156. doi: 10.3389/fonc.2021.697156 . PMC   8280784 . PMID   34277442.
  31. Casanova M, Brennan B, Alaggio R, Kelsey A, Orbach D, van Noesel MM, Corradini N, Minard-Colin V, Zanetti I, Bisogno G, Gallego S, Merks JH, De Salvo GL, Ferrari A (March 2020). "Inflammatory myofibroblastic tumor: The experience of the European pediatric Soft Tissue Sarcoma Study Group (EpSSG)". European Journal of Cancer. 127: 123–129. doi:10.1016/j.ejca.2019.12.021. PMID   32007712. S2CID   211012731.
  32. 1 2 Mohamed M, Fisher C, Thway K (June 2017). "Low-grade fibromyxoid sarcoma: Clinical, morphologic and genetic features". Annals of Diagnostic Pathology. 28: 60–67. doi:10.1016/j.anndiagpath.2017.04.001. PMID   28648941.
  33. Lin TL, Yang CS, Juan CK, Weng YC, Chen YJ (January 2020). "Superficial CD34-Positive Fibroblastic Tumor: A Case Report and Review of the Literature". The American Journal of Dermatopathology. 42 (1): 68–71. doi: 10.1097/DAD.0000000000001355 . PMID   30702454.
  34. Wangsiricharoen S, Ali SZ, Wakely PE (2021). "Cytopathology of myxoinflammatory fibroblastic sarcoma: a series of eight cases and review of the literature". Journal of the American Society of Cytopathology. 10 (3): 310–320. doi:10.1016/j.jasc.2020.12.004. PMID   33431307. S2CID   231585966.
  35. Tivoli YA, Thomas JA, Chen AF, Weiss ET (November 2013). "Acral myxoinflammatory fibroblastic sarcoma successfully treated using Mohs micrographic surgery". Dermatologic Surgery. 39 (11): 1709–11. doi:10.1111/dsu.12308. PMID   24118192. S2CID   39916092.
  36. 1 2 3 Martínez-Trufero J, Cruz Jurado J, Gómez-Mateo MC, Bernabeu D, Floría LJ, Lavernia J, Sebio A, García Del Muro X, Álvarez R, Correa R, Hernández-León CN, Marquina G, Hindi N, Redondo A, Martínez V, Asencio JM, Mata C, Valverde Morales CM, Martin-Broto J (July 2021). "Uncommon and peculiar soft tissue sarcomas: Multidisciplinary review and practical recommendations for diagnosis and treatment. Spanish group for Sarcoma research (GEIS - GROUP). Part I". Cancer Treatment Reviews. 99: 102259. doi:10.1016/j.ctrv.2021.102259. ISSN   0305-7372. PMID   34311246.
  37. Martin-Broto J, Mondaza-Hernandez JL, Moura DS, Hindi N (June 2021). "A Comprehensive Review on Solitary Fibrous Tumor: New Insights for New Horizons". Cancers. 13 (12): 2913. doi: 10.3390/cancers13122913 . PMC   8230482 . PMID   34200924.
  38. Hansen T, Katenkamp K, Brodhun M, Katenkamp D (August 2006). "Low-grade fibrosarcoma--report on 39 not otherwise specified cases and comparison with defined low-grade fibrosarcoma types". Histopathology. 49 (2): 152–60. doi:10.1111/j.1365-2559.2006.02480.x. PMID   16879392. S2CID   39305599.
  39. Clarke LE (October 2012). "Fibrous and fibrohistiocytic neoplasms: an update". Dermatologic Clinics. 30 (4): 643–56, vi. doi:10.1016/j.det.2012.06.005. PMID   23021051.
  40. Murshed KA, Al-Bozom I, Ammar A (August 2021). "Sclerosing epithelioid fibrosarcoma: in-depth review of a genetically heterogeneous tumor". APMIS. 129 (8): 455–460. doi: 10.1111/apm.13157 . PMID   34048081.