A non-ossifying fibroma (NOF) is a

benign Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous benign tumor, ''benign'' tumor in that a malign ...

bone tumor A bone tumor is an abnormal growth of tissue in bone, traditionally classified as noncancerous (benign) or cancerous (malignant). Cancerous bone tumors usually originate from a cancer in another part of the body such as from lung, breast, thyroi ...

of the osteoclastic giant cell-rich tumor type. It generally occurs in the

metaphysis The metaphysis is the neck portion of a long bone between the epiphysis and the diaphysis. It contains the growth plate, the part of the bone that grows during childhood, and as it grows it ossifies near the diaphysis and the epiphyses. The metaph ...

of long bones in children and adolescents. Typically, there are no symptoms unless there is a

fracture Fracture is the separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displa ...

. It can occur as part of a syndrome such as when multiple non-ossifying fibromas occur in

neurofibromatosis Neurofibromatosis (NF) is a group of three conditions in which tumors grow in the nervous system. The three types are neurofibromatosis type I (NF1), neurofibromatosis type II Neurofibromatosis type II (also known as MISME syndrome – multi ...

, or Jaffe-Campanacci syndrome in combination with cafe-au-lait spots,

mental retardation Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation,Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by signific ...

hypogonadism Hypogonadism means diminished functional activity of the gonads—the testes or the ovaries—that may result in diminished production of sex hormones. Low androgen (e.g., testosterone) levels are referred to as hypoandrogenism and low estrogen ...

, eye and cardiovascular abnormalities. Diagnosis is by

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

, usually when investigating a person for something else.

Medical imaging Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to rev ...

typically shows a well defined radiolucent lesion, with a distinct multilocular appearance, sometimes looking like bubbles. It is usually around 1-2cm in size, but be as large as 7cm. They consist of foci consist of

collagen Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...

rich

connective tissue Connective tissue is one of the four primary types of animal tissue, along with epithelial tissue, muscle tissue, and nervous tissue. It develops from the mesenchyme derived from the mesoderm the middle embryonic germ layer. Connective tiss ...

fibroblast A fibroblast is a type of cell (biology), biological cell that synthesizes the extracellular matrix and collagen, produces the structural framework (Stroma (tissue), stroma) for animal Tissue (biology), tissues, and plays a critical role in wound ...

histiocyte A histiocyte is a vertebrate cell that is part of the mononuclear phagocyte system (also known as the reticuloendothelial system or lymphoreticular system). The mononuclear phagocytic system is part of the organism's immune system. The histiocyt ...

s and

osteoclast An osteoclast () is a type of bone cell that breaks down bone tissue. This function is critical in the maintenance, repair, and remodeling of bones of the vertebral skeleton. The osteoclast disassembles and digests the composite of hydrated pro ...

s. Usually no treatment is required. Surgical curettage and bone grafting may be required if it is large. It is found in 30-40% of children and adolescents, but rare in adults as most have resolved by this time. They do not become

malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

. It affects twice as many males as females. A NOF was identified on the mandible of Qafzeh 9, an early anatomically modern human dated to 90–100 000 yrs B.P.Coutinho Nogueira D, Dutour O, Coqueugniot H, Tillier A.-m., (2019) Qafzeh 9 mandible (ca 90–100 kyrs BP, Israel) revisited : μ-CT and 3D reveal new pathological conditions, International Journal of Paleopathology, Vol 26, pp.104-110, https://doi.org/10.1016/j.ijpp.2019.06.002

Signs and symptoms

Most people with non-ossifying fibroma have no symptoms. If the tumor is large, there may be pain over the affected area, a

pathological fracture A pathologic fracture is a bone fracture caused by weakness of the bone structure that leads to decrease mechanical resistance to normal mechanical loads. This process is most commonly due to osteoporosis, but may also be due to other pathologies ...

, and the affected limb might not function properly. It can occur as part of a syndrome such as when multiple non-ossifying fibromas occur in

, or Jaffe-Campanacci syndrome in combination with cafe-au-lait spots,

, eye and cardiovascular abnormalities.

Diagnosis

It is usually diagnosed by

x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

, when investigating another problem. The tumor presents as a well defined radiolucent lesion, with a distinct multilocular appearance, sometimes looking like a "soap bubble". If small and no symptoms, then biopsy is not needed.

Additional images

References

External links

*
Wheeless' Textbook of Orthopaedics: Nonossifying Fibroma
Osteopathies {{musculoskeletal-disease-stub

Signs and symptoms

Diagnosis

Additional images

See also

References

External links