Home

Malignant fibrous histiocytoma orthobullets

Undifferentiated Pleomorphic Sarcoma - Orthobullet

  1. Undifferentiated Pleomorphic Sarcoma, previously known as malignant fibrous histiocytoma, is a high-grade, aggressive, malignant fibrogenic tumor. The condition is typically seen in patients 55-80 years of age who present with a slow-growing, painless mass
  2. Pathology⎪Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) 27 May 2020 · The Orthobullets Podcast In this episode, we review the high-yield topic of Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) from the Pathology section
  3. Histiocytomas, also known as benign fibrous histiocytomas, are extremely rare, benign histiocytic lesions of bone. Patients typically present with regional pain and swelling. Diagnosis is made with radiographs that show a characteristic lytic lesion with a sclerotic border and biopsy with histology showing spindle cells and foamy macrophages in.
  4. MB BULLETS Step 1 For 1st and 2nd Year Med Students. MB BULLETS Step 2 & 3 For 3rd and 4th Year Med Students. ENT BULLET
  5. Fibrosarcoma of Bone is a malignant, high-grade, fibrogenic tumor of bone that usually occurs in patients > 50 years of age who presents with regional pain and swelling. Diagnosis is made with a biopsy and histology showing atypical spindle cells in a herringbone pattern
  6. Fibrous Dysplasia is a developmental abnormality caused by a GS alpha protein mutation that leads to failure of the production of normal lamellar bone. The condition usually presents in patients who are less than 30 years of age with an asymptomatic lesion that is found incidentally on radiographs

Malignant Peripheral Nerve Sheath Tumors, also known as neurofibrosarcoma or malignant schwannoma, are malignant tumors that may occur as solitary lesions or be associated with neurofibromatosis. The condition usually presents in patients between 20 and 50 years old with soft-tissue masses associated with a peripheral nerve or prior neurofibroma • Malignant giant cell tumor of tendon sheath: Fibrogenic & Fibrohistiocytic • Fibroma • Fasciitis (nodular or proliferative) • Fibrous histiocytoma: x • Fibrosarcoma • Myxofibrosarcoma • Malignant fibrous histiocytoma. Lipogenic • Lipoma • Myxoid liposarcoma • Pleomorphic liposarcoma: Muscle tissue • Leiomyoma • Rhabdomyoma: Neuroblastomas are malignant tumors that develop from sympathetic neural tissue with most cases arising near the adrenal gland or the spinal cord. The condition usually presents in children younger than age 2 with fever, weight loss, and diarrhea Histiocytoma (Benign Fibrous Histiocytoma) Desmoplastic Fibroma Pleomorphic Sarcoma of Bone (Malignant Fibrous Histiocytoma) Fibrosarcoma of Bon 90% occur in the lower extremity. 50% occur in the distal tibia. risk factors. >50% involvement of transverse diameter. >33mm length in weight-bearing bones (femur and tibia) treatment. cast immobilization. indications. nondisplaced fractures

Pathology⎪Malignant Fibrous Histiocytoma (Pleomorphic

Metastatic Disease of the Extremity is a malignant pathologic process that is the most common cause of destructive bone lesions in the extremities of adult patients. Diagnosis is made with plain radiographs of the affected limb including the joint above and below the lesion 27 мая 2020 · The Orthobullets Podcast In this episode, we review the high-yield topic of Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) from the Pathology section. --- Send in a voice message: https://anchor.fm/orthobullets/messag

In this episode, we review the high-yield topic of Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) from the Pathology section Terminology. Previously known as a myxoid variant of malignant fibrous histiocytoma 7.. Epidemiology. Typically presents in older patients (6 th decade) 3.There may be male predilection. Although rare in general, it is considered the most common soft tissue tumor to present in late adult life

Definition / general. Spectrum of malignant fibroblastic lesions with myxoid stroma, pleomorphism and curvilinear vessels. A myxoid subtype of undifferentiated pleomorphic sarcoma (formerly myxoid malignant fibrous histiocytoma [MFH]) See also Heart chapter the most common malignancy of bone is metastatic disease. the most common primary malignancy of bone is myeloma. Age & location. usually occurs in children and young adults. bimodal distribution of occurrence. majority occur in the second decade of life. second peak in occurrence is in elderly patients with Paget's disease

Deep fibrous histiocytoma: may extend into hypodermis (Am J Surg Pathol 2008;32:354) Cellular: highly cellular and look blue at low power with thick collagen bundles (Am J Surg Pathol 1994;18:668) Lipidized: also known as 'ankle type' Am J Dermatopathol 2000;22:12 Orthobullets. December 10, 2018 ·. Chondromyxoid fibroma is a rare, benign tumor that usually causes pain and can be locally aggressive. Histologically, it is characterized by the presence of both myxoid and fibrous elements. It is found most often in the metaphysis around the knee in the proximal tibia, proximal fibula, or distal femur

Histiocytoma (Benign Fibrous Histiocytoma) - Orthobullet

A malignant transformation of bone infarct is a common complication. Cases of various histological types of sarcomas, mainly of mesenchymal origin (malignant fibrous histiocytoma, fibrosarcoma, liposarcoma) have been described in single bone infarcts as well as in multiple infarcts complicating systemic diseases (alcoholism, anaemia) [33-38 Solitary fibrous tumor (SFT), also known as fibrous tumor of the pleura, is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue including seminal vesicle. Approximately 78% to 88% of SFT's are benign and 12% to 22% are malignant MB BULLETS Step 1 For 1st and 2nd Year Med Students. MB BULLETS Step 2 & 3 For 3rd and 4th Year Med Students. ORTHO BULLETS Orthopaedic Surgeons & Provider Malignant fibrous histiocytoma (MFH) is widely regarded as the commonest soft tissue sarcoma of adulthood which tends to occur in the deep soft tissues of the extremities and the retroperitoneum. Uncertain histogenesis and numerous subtypes make MFH a rather controversial entity. These tumours are r A, Malignant fibrous histiocytoma of the lateral ankle presenting as a large, painless mass. B, Free-flap coverage was required after resection. Nathan F. Gilbert, MD, et al Volume 17, Number 1, January 2009 41. and nerve compression leading to neurologic deficit is a late, thoug

myxoid malignant fibrous histiocytoma, myxoid liposarcoma, low grade fibromyxoid sarcoma and myxoid chondrosarcoma in differential diagnosis. While low-grade malignant fibrous histiocytoma (myxofibrosarcoma) is a hypocellular lesion with abundant myxoid stroma, there is always nuclear hyperchromasia and cytologic atypia leading to a malignant This paper concerns a case of Malignant Fibrous Histiocytoma (MFH) of the Breast in a 73-years-old woman. A lump was found in her right breast, measuring 1.7 cm in diameter. Surgical excision followed, and pathology revealed a highly atypical spindle cell tumor. Immunohistochemistry along the histological features, excluded the possibility of carcinoma, malignant phyllodes tumor, or another.

Histiocytoma (Benign Fibrous Histiocytoma) - Pathology

  1. Fibrous lesions [21] 12p13 aberrations (three cases) and trisomy 2 (three cases) NA NA NA Benign Aneurysmal bone cyst [91] 16q22 and 17p-13 CDH11-USP6 NA FISH or RT-PCR Benign Osteochondroma [16] 8q22-24.1 EXT1 NA NA Benign Lipoma [14] Majority have normal karyotype NA NA NA Benign Lipoblastoma [31] Rearrangement of 8q12, polysomy 8 PLAG1.
  2. A malignant transformation of bone infarct is a common complication. Cases of various histological types of sarcomas, mainly of mesenchymal origin (malignant fibrous histiocytoma, fibrosarcoma, liposarcoma) have been described in single bone infarcts as well as in multiple infarcts complicating systemic diseases (alcoholism, anaemia) [33-38.
  3. These are heterogenous group of tumors; malignant fibrous histiocytoma, spindle cell sarcoma, leiomyosarcoma, fibrosarcoma and angiosarcoma and its benign counterpart leiomyoma. Leiomyosarcoma of bone arises from preexisting smooth muscle cells in the media of intraosseous blood vessels

Fibrosarcoma of Bone - Pathology - Orthobullet

Malignant fibrous histiocytoma has been classified as a miscellaneous tumor since 2013; however, we classified it as a fibrohistiocytic tumor in the present study. We described the number, registration rate (per million population, standardized by age-class of the Segi's World Standard Population), and proportion of bone tumor cases by. Bizarre parosteal osteochondromatous proliferations (BPOP), also known as Nora lesions, are benign exophytic osteochondral lesions which have an appearance similar to an osteochondroma and are typically seen in the hands and feet. On imaging, BPOPs are shown to be continuous with the underlying cortex, but usually without continuation of the medulla

Fibrous Dysplasia - Pathology - Orthobullet

Malignant fibrous histiocytoma may occur in bones with prior insult such as radiation, surgery, fracture, avascular necrosis, Paget's disease or fibrous dysplasia. Clinically, patients present with acute or chronic pain, tenderness and swelling over the lesion. Pathologically, malignant fibrous histiocytoma appears as a lobulated, gray-white. Pathology⎪Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) 27 mai 2020 · The Orthobullets Podcast In this episode, we review the high-yield topic of Malignant Fibrous Histiocytoma (Pleomorphic Sarcoma) from the Pathology section Deep fibrous histiocytoma: may extend into hypodermis (Am J Surg Pathol 2008;32:354) Cellular: highly cellular and look blue at low power with thick collagen bundles (Am J Surg Pathol 1994;18:668) Lipidized: also known as 'ankle type' Am J Dermatopathol 2000;22:12 Malignant transformation of fibrous dysplasia may be to osteosarcoma, fibrosarcoma, chondrosarcoma, and malignant fibrohistiocytoma 2. Seven reported cases of malignant transformation of fibrous dysplasia into osteogenic sarcoma have been reported in patients with Mazabraud syndrome justifying clinical and radiological follow-up 2, 15

Fibrosarcoma and undifferentiated pleomorphic sarcoma (formerly malignant fibrous histiocytoma of bone) Fibrosarcomas and undifferentiated pleomorphic sarcoma have similar characteristics to osteosarcomas but produce fibrous tumor cells (rather than bone tumor cells), affect the same age group, and pose similar problems Alveolar Soft Part Sarcoma. by Keila Torres, MD, PhD and Raphael Pollock, MD, PhD Also available in Chinese, French, Italian, Japanese and Spanish. Abstract. Alveolar soft part sarcoma (ASPS) is a rare, poor prognosis neoplasm of unknown histogenesis with a distinctive histology, specific molecular characteristics, and unique clinical behaviors.ASPS generally develop in younger patients Malignant fibrous histiocytoma (MFH) is a pleomorphic sarcoma, occurring most frequently in the deep soft tissues of the extremities. Primary osseous MFH is less common. MFH is the most common soft-tissue sarcoma of late adult life. Although its imaging appearance is often nonspecific, any deep-seated invasive intramuscular mass in a patient. Liposclerosing myxofibrous tumor. Dr Bahman Rasuli and Dr Yuranga Weerakkody et al. Liposclerosing myxofibrous tumors (LSMFT), also known as polymorphic fibro-osseous lesions of bone, are rare benign fibro-osseous lesions that have a predilection for the intertrochanteric region of the femur. On this page

Occasionally, a destructive lesion such as a chondrosarcoma or malignant fibrous histiocytoma is the cause of the fracture. Pediatric Considerations. In children and adolescents, the most common benign cause of a pathologic fracture is a unicameral bone cyst or a NOF The diagnosis is not as obvious if the patient is middle aged with a pathologic fracture through a malignant fibrous histiocytoma of bone that produces no matrix. The reason for emphasizing an awareness of pathologic fractures through a primary bone sarcoma is that the management of pathologic fractures is dramatically different in sarcoma and.

Malignant Peripheral Nerve Sheath Tumor - Pathology

Differential Groups - Pathology - Orthobullet

  1. Giant cell tumor of tendon sheath is defined as a benign reactive lesion which is similar to PVNS. Giant cell tumor of tendon sheath is also named tenosynovial giant cell tumor. GCT of tendon sheath is a circumscribed tumor that does not always arise from the tendon sheath but may arise from the synovium. Most common in patients after 30 years.
  2. Enchondroma is a benign indolent intramedullary hyaline cartilage neoplasm. Accounts for 10% of all benign osseous tumors. Limited growth, most lesions are less than 5 cm in maximal dimension. Bones grow from a cartilaginous growth plate that gradually lengthens and turns into bone as it lengthens. An enchondroma can be thought of as an island.
  3. Undifferentiated pleomorphic sarcoma (UPS), also undifferentiated pleomorphic sarcoma (PUS) and previously malignant fibrous histiocytoma (abbreviated MFH), is a type of cancer and soft tissue sarcoma.. It is considered a diagnosis of exclusion for sarcomas that cannot be more precisely categorized. Other sarcomas are cancers that form in bone and soft tissues, including muscle, fat, blood.
  4. Because malignant transformation has not been described, asymptomatic lesions need not be excised. In fact, surgical resection should be limited to those who are symptomatic, as the incidence of postoperative complications is high. [51, 52] Bilateral back elastofibroma after resection of a malignant fibrous histiocytoma has been described

30 year old man with fibrous dysplasia in the calcaneus (Foot Ankle Spec 2017;10:72) 62 year old man with angiosarcoma arising in fibrous dysplasia after radiation therapy (Oral Radiol 2019 Jul 31 [Epub ahead of print]) 62 year old woman with Mazabraud syndrome and malignant transformation into osteosarcoma (Case Rep Orthop 2019;2019:2638478 Enostosis. Enostoses, also known as bone islands, are common benign sclerotic bone lesion that usually represent incidental findings. They constitute a small focus of compact bone within cancellous bone . Enostoses can be seen on radiographs, CT, and MRI, and are considered one of the skeletal don't touch lesions Sternum fracture orthobullets. Flail Chest. Flail Chest is a traumatic chest injury defined as segmental fractures of 3 or more ribs and is often associated with pulmonary injuries such as hemothorax and pneumothorax. Diagnosis is made with radiographs of the chest. Treatment can be nonoperative or operative depending on the presence of respiratory compromise, the number of

Differential diagnosis • Malignant fibrous histiocytoma • Fibrosarcoma • Giant cell tumours • Ewing's sarcoma • Osteoblastoma 70. Treatment • Long bone involvement→ amputation is a prime requisite. • Radical resection • Primary X-ray radiation is of no avail The term fibromatosis refers to a group of soft tissue tumors which have certain characteristics in common, including absence of cytologic and clinical malignant features, a histology consistent with proliferation of well-differentiated fibroblasts, an infiltrative growth pattern, and aggressive clinical behavior with frequent local recurrence.It is classed by the World Health Organization as. 4. Malignant fibrous histiocytoma (MFH) MFH adalah salah satu jenis sarcoma, yaitu neoplasma ganas tanpa asal yang jelas, yang muncul dari jaringan lunak dan tulang. MFH dianggap sebagai penyakit tulang yang langka. Penyakit ini biasanya menyerang pasien berusia 50-70 tahun, meskipun ia dapat muncul di segala usia 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 GNET.. Recurrence is common Alveolar soft part sarcoma, abbreviated ASPS, is a very rare type of soft-tissue sarcoma, that grows slowly and whose cell of origin is unknown.. ASPS arises mainly in children and young adults and can migrate (metastasize) into other parts of the body, typically the lungs and the brain.Typically, ASPS arises in muscles and deep soft tissue of the thigh or the leg (lower extremities), but can.

The mass called solitary fibrous tumor is a rare malignancy that has a mesenchymal origin. This type of neoplasm makes up about 2% of all soft tissue tumors. Although most of it cases are benign, 1 in every 5 cases are found to be malignant [1, 2] Osteochondromas are a relatively common imaging finding, accounting for 10-15% of all bone tumors and approximately 35% of all benign bone tumors. Although usually thought of as a benign bone tumor, they may be thought of as a developmental anomaly. They are frequently asymptomatic and have very low malignant potential if sporadic and solitary Spindle cell sarcoma is a soft-tissue tumour which can start in the bone. Spindle cell sarcomas of the bone are often found in the arms, legs and pelvis. They most commonly arise in patients over the age of 40 and are extremely rare, making up just 2-5% of all primary bone cancer cases

Webpathology

Malignant fibrous histiocytoma: inherited and sporadic forms have loss of heterozygosity at chromosome bands 9p21-22-evidence for a common genetic defect. Martignetti JA, Gelb BD, Pierce H, Picci P, Desnick RJ: Genes, chromosomes & cancer. 2000 ; 27 (2) : 191-195. PMID 1061280 Malignant fibrous histiocytoma (MFH) and fibrosarcoma. Fibrosarcoma is not uncommon in the iliac bone (9%), proximal femur (9%), but uncommon in ischial and pubic bones (3%). MFH is also not uncommon in the proximal femur (12%), but rare in other components of the pelvis. Fibrosarcoma and MFH share the same radiologic features, and these are.

Bone island, also called an enostosis, is a benign bone tumor mostly encountered as an incidental and asymptomatic finding. They are round and small (2 to 20 mm) intramedullary condensations composed of lamellar cortical bone. Essentially it is intramedullary displacement of compact lamellar bone. Any bone can be involved, but most common areas. Fig. 3A —31-year-old woman (patient 8 in Table 1) with history of steroid therapy for ulcerative colitis and malignant fibrous histiocytoma (MFH) arising at site of bone infarction. A, Lateral radiograph of knee shows small focus of osteolysis and cortical irregularity (white arrowheads) along anterior aspect of distal femur

Intradermal nodular fasciitis requires segregation from fibrous histiocytoma and spindle cell sarcomas. A fibrous histiocytoma is comprised of spindle-shaped cells admixed with histiocytic cells, entrapped bundles of collagen, and hyaline substance appearing at the tumor perimeter. Superimposed epidermis demonstrates acanthosis Another tumor type whose existence as a separate true diagnostic category has been deeply reconsidered in the past decades is malignant fibrous histiocytoma (MFH). Indeed, since fibroblast and its variants are the predominant cell types found in these tumors, it has been suggested that the diagnostic entity MFH should be rather classified as a. Malignant lesions Undifferentiated pleomorphic sarcoma Previously known as malignant fibrous histiocytoma, this is the most common soft tissue sarcoma in adults with a wide age range of 30-80 years old and a slight male predilection. It is thought to arise from undifferentiated mesenchymal stem cells and usually occurs in the soft tissues of.

Characteristic karyotypic anomalies identify subtypes of malignant fibrous histiocytoma. Mandahl N, Heim S, Willen H, Rydholm A, Eneroth M, Nilbert M, Kreicbergs A, Mitelman F. Genes Chromosomes Cancer. 1989 Sep;1(1):9-14. PMID 2562116 : Extraskeletal osteosarcoma: a case report. Mavrogenis AF, Papadogeorgou E, Papagelopoulos PJ Pulmonary Myxoid Sarcoma with EWSR1-CREB1 Translocation is an extremely rare tumor with only around 15 cases being reported in the medical literature. The condition is generally observed in young adults. Even though both males and females are affected, a strong preference for females is observed. No specific racial or ethnic group predilection.

Neuroblastoma - Pathology - Orthobullet

nant fibrous histiocytoma (MFH). In fact, there is evidence that a subpopulation (about 20%) of poorly differentiated sarcomas of the retroperitoneum previ-ously classified as MFH likely represent dedifferen-tiated liposarcoma. ALT-WDLPS has been found to contain supernu-merary ring chromosomes or giant chromosomes Malignant fibrous histiocytoma (MFH) is a type of histiocytoma and is the most common soft tissue sarcoma of late adult life. However, it is relatively uncommon in the head and neck area. It usually occurs/develops in the lower extremities and in the retroperitonium. This tumour is difficult to distinguish histologically from other sarcomas and carcinomas 【Abstract】 <正>Malignant fibrous histiocytoma(MFH) is an aggressive soft-tissue sarcoma that most commonly occurs in the skeletal muscle of the extremities or retroperitoneum of middle and late adulthood.We present a case of 65-year-old women who presented with an asymptomatic erythematous nodule with central ulceration on left temporal area.She was diagnose

These tumors have a high risk of malignant transformation, compared with fibrous dysplasia.1, 2, 4 Malignant transformation occurs because of malignant fibrous histiocytoma or osteosarcoma, and it was estimated to occur between 10% and 16% of cases. In this study, one patient (11.1%) had malignant tumor for low-grade osteosarcoma - Malignant fibrous histiocytoma - Synovial - anecdotally malignant superficial lesions will not appear as a discrete circular mass, but there are always exceptions; - size of mass:- if mass is > five cm, esp if it is deep and in thigh, it is likely to be a. Malignant fibrous histiocytoma at the site of a total hip replacement: review of the literature and case report. Skeletal Radiol, 26 (1997), pp. 559-563. View Record in Scopus Google Scholar. 49. WJ Gillespie, CMA Frampton, RJ Henderson, PM Ryan. The incidence of cancer following total hip replacement Historically, MFS was described as a kind of malignant fibrous histiocytoma (MFH) but has gradually been recognized as a distinct histotype. The histopathologic patterns of myxofibrosarcoma are characterized by a myxoid component of extracellular matrix, pleomorphic spindle cells, and curvilinear blood vessels

Further, the dedifferentiated tumor had three mesenchymal elements: osteosarcoma, malignant fibrous histiocytoma, and fibrosarcoma. This histological heterogenicity may be due to mesodermal. Malignant fibrous histiocytoma. The is rarely occuring spindle shaped cell carcinoma, which affects upper and lower limbs. They mainly develop in middle aged individuals. Fibrosarcoma. This type of Spindle Cell sarcoma involves the thigh bone. Leiomyosarcoma The primary neoplasms for the 52 FNA patients included 47 sarcomas (10 malignant fibrous histiocytomas and 16 other types), I intramuscular myxoma, 2 lymphomas, and 2 spindle cell (sarcomatoid. Diagnoses included osteosarcoma in five patients, chondrosarcoma in three patients, giant cell tumors in three patients , and malignant fibrous histiocytoma in one patient . Five osteosarcoma patients were treated with adjuvant chemotherapy . At the time of the surgery, measurements obtained with preoperative magnetic resonance imaging were. 1-Malignant Fibrous Histiocytoma : a) Incidence b) Location c) Radiographic Features 87. a) Incidence : -MFH are aggressive tumors which account for 25-40% of all adult soft tissue sarcoma making them the most common type -Old age -They are the most frequent soft tissue sarcoma to occur as a result of radiotherapy and are also seen on a.

(DFSP = dermatofibrosarcoma protuberans; MPNST = malignant peripheral nerve sheath tumour; MMMT = malignant mixed Mullerian tumour; PNET = primitive neuro-ectodermal tumour; MFH = malignant fibrous histiocytoma.)DFSP 18.00% Leiomyosarcoma 12.70% Osteosarcoma 8.70% Synovial 8.00% MPNST 6.0% MMMT 6.0% Liposarcoma + atypical lipoma 5.3% Fibromatosis (desmoid 4) 4.7% Rhabdomyosarcoma 4.0% Subtype. Malignant fibrous histiocytoma, or pleomorphic sarcoma (uncertain origin) Giant cell tumors, or osteoclastomas (arise from giant cells of bone) Adamantinomas (arise from epithelial cells) The intraoperative photo shows a low-grade chondrosarcoma of the distal femur delimited by K-wires (arrows)

The malignant non-cartilaginous component is most frequently malignant fibrous histiocytoma, osteosarcoma or fibrosarcoma, although other malignant tumors have been reported as the differentiated component. The cartilaginous and non-cartilaginous components are often adjacent, and the term collision of two tumors has been applied to this lesion Bizarre parosteal osteochondromatous proliferation (BPOP) is a rare lesion that occurs most commonly in the hands and feet. This lesion grows rapidly and has aggressive features on imaging studies as well as confusion findings on histopathology, leading to many errors in diagnosis and potentially inappropriate treatments

Histiocytoma (Benign Fibrous Histiocytoma) - Pathology - OrthobulletsMalignant Fibrous Histiocytoma (Pleomorphic Sarcoma) - Pathology - OrthobulletsMalignant Fibrous Histiocytoma/Undifferentiated Pleomorphic Sarcoma | Basicmedical KeyLow-grade malignant fibrous histiocytoma — Clinical MRI

Bramwell VH, Steward WP, Nooij M, et al. Neoadjuvant chemotherapy with doxorubicin and cisplatin in malignant fibrous histiocytoma of bone: A European Osteosarcoma Intergroup study. J Clin Oncol 1999; 17:3260. Palmerini E, Maki RG, Staals EL, et al. Primary angiosarcoma of bone: a retrospective analysis of 60 patients from 2 institutions Primary lymphoma of bone is a rare tumor which comprises approximately 5 - 7% of malignant bone tumors and 5% of the extranodal non-Hodgkin's lymphomas present as primary lymphoma of bone. However secondary bone involvement is seen about 16 - 20% of patients with lymphoma. Lymphoma involving bone can be separated into four groups: 1 Most malignant fibrous histiocytomas developed in the retroperitoneum are dedifferentiated liposarcomas: a review of 25 cases initially diagnosed as malignant fibrous histiocytoma. Modern Pathology , 16 (3), 256 Benign fibrous histiocytoma: Extremely rare, infiltrative lesion of soft tissue which causes destruction of adjacent bones, arising from primitive mesenchymal cells (Medicine (Baltimore) 2019;98:e17144) Primary lesions of bone are even rarer, with cases reported to involve the spine and distal portions of long bones (J Bone Oncol 2018;12:78