A nonossifying fibroma (also called fibroxanthoma) is a common benign bone tumor in children and adolescents. However, it is controversial whether it represents a true neoplasm or rather a developmental disorder of growing bone. Radiographically, the tumor presents as a well marginated radiolucent lesion, with a distinct multilocular appearance. These foci consist of collagen rich connective tissue, fibroblasts, histiocytes and osteoclasts. They originate from the growth plate, and are located in adjacent parts of the metaphysis and diaphysis of long bones, most often of the legs. No treatment is needed in asymptomatic patients and spontaneous remission with replacement by bone tissue is to be expected.

Multiple nonossifying fibromas occur in Jaffe-Campanacci syndrome in combination with cafe-au-lait spots, mental retardation, hypogonadism, ocular and cardiovascular abnormalities.

Typically patients present with progressive pain, often long standing and/or bony swelling and restricted range of movement in affected limb 3,12. The latter is most often the case in bones with little overlying soft tissues (e.g. short tubular bones of the hands and feet).

Most chondromyxoid fibromas are located in the metaphyseal region of long bones (60%), and may extend to the epiphyseal line and even rarely abut the articular surface 3,12. They are almost never just epiphyseal 3. The classical site is the upper 1/3rd of tibia ( which accounts for 25% of all cases) with the small tubular bones of the foot, the distal femur and pelvis being other relatively common locations 12.

Rarely occur in the skull or skull base.

The soft fibroma (fibroma molle) or fibroma with a shaft (acrochordon, skin tag, fibroma pendulans) consist of many loosely connected cells and less fibroid tissue. It mostly appears at the neck, armpits or groin. The photo shows a soft fibroma of the eyelid.

The hard fibroma (fibroma durum) consists of many fibres and few cells, e.g. in skin it is called dermatofibroma (fibroma simplex or nodulus cutaneous). A special form is the keloid, which derives from hyperplastic growth of scars.

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.

Although they may be regarded as a tumor of the skin, the lesions arise from tendons and aponeuroses in superficial sites, and are therefore properly classified as in the category "soft tissue tumor."

The biological nature of Fibroma of tendon sheath is not known, but the category appears to comprise a number of different pathologic processes. It is considered that about one-third of the lesions in this category may be acral variants of the entity, nodular fasciitis.

Dermatofibromas are hard solitary slow-growing papules (rounded bumps) that may 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 applying lateral pressure, there is a central depression of the dermatofibroma. Although typical dermatofibromas cause little or no discomfort, itching and tenderness can occur. Dermatofibromas can be found anywhere on the body, but most often they are found on the legs and arms. They occur most often in women; the male to female ratio is about 1:4. The age group in which they most commonly occur is 20 to 45 years.

Some physicians and researchers believe dermatofibromas form as a reaction to previous injuries such as insect bites or thorn pricks. They are composed of disordered collagen laid down by fibroblasts. Dermatofibromas are classed as benign skin lesions, meaning they are completely harmless, though they may be confused with a variety of subcutaneous tumours. Deep penetrating dermatofibromas may be difficult to distinguish, even histologically, from rare malignant fibrohistocytic tumours like dermatofibrosarcoma protuberans.

Dermatofibromas typically have a positive "buttonhole sign", or central dimpling in the center.

CGCG lesions are found more commonly in the anterior of the maxilla and the mandible in younger people (before age 20). They are characterized by large lesions that expand the cortical plate and can resorb roots and move teeth. They are composed of multi-nucleated giant cells. CGCG has a slight predilection for females.

Radiographically :

It appears as multilocular radiolucencies of bone.The margin of the lesion has scalloped appearance and is well demarcated. Resorption and divergence of roots is also seen.

There are two types of CGCG's, non-aggressive and aggressive. The former has a slow rate of growth and thus less likely to resorb roots and perforate the cortical plate. The aggressive form has rapid growth and thus is much more likely to resorb roots and perforate the cortical plate. It also has a high rate for recurrence and can be painful and cause paresthesia.

Differential diagnosis to include: odontogenic keratocyst (OKC), ameloblastoma, odontogenic myxoma, hemangioma, central odontogenic fibroma, hyperparathyroid tumor, and cherubism.

The tibia is the most commonly involved bone, accounting for 85% of cases. It is usually painless, although there may be localized pain or fracture, and presents as a localized firm swelling of the tibia in children less than two decades old (median age for males 10, females 13). Several authors have related this non-neoplastic lesion to adamantinoma - a tumor involving subcutaneous long bones - stating the common cause to be fibrovascular defect. However, the latter is distinguished from an osteofibrous dysplasia by the presence of soft tissue extension, intramedullary extension, periosteal reaction and presence of hyperchromic epithelial cells under the microscope.

Osteofibrous dysplasia may also be mistaken for fibrous dysplasia of bone, although osteofibrous dysplasia is more likely to show an immunohistochemical reaction to osteonectin, neurofibromin, and S-100 protein.

The majority of cases occur in the second and third decades, with approximately 75% of cases occurring before the age of 30 years 1,12-15. There is no recognised gender predilection. Examples have however been seen in patients up to the age of 75 years. In some series there is a male predilection 12 whilst in others no such distribution is found 2

Patient will present with a slow growing, deep-seated, firm mass, often presenting bilaterally. There may be pain or tenderness, but this is rare.

frequency:- rare type of cyst

It can occur at any age, mostly between 2nd and 3rd decade of life.

Diameter is 2 to 4 cm

swelling pain maybe present.

intra bony expansions may produce hard bony expansion.

may perforate cortical bones

also it extends to soft tissue

maybe asymptomatic

The central odontogenic fibroma is a rare benign odontogenic tumor. It is more common in adults, with the average age being 40. It is twice as likely to affect women than men. It is usually found either in the anterior maxilla or the posterior mandible. Radiographically it presents with either radiolucency or mixed radiolucency/opaque. The simple type is characterized by delicate fibrillar stroma of collagen containing fibroblasts; the WHO type is characterized by more mature fibrillar stroma of collagen. Treatment is by surgical removal

Benign fibrous histiocytomas (also known as dermal dendrocytoma, dermatofibroma, fibrous dermatofibroma, fibrous histiocytoma, fibroma simplex, nodular subepidermal fibrosis, and sclerosing hemangioma) are benign skin growths.

Central giant-cell granuloma (CGCG) is a benign condition of the jaws. It is twice as likely to affect women and is more likely to occur in 20- to 40-year-old people. Central giant-cell granulomas are more common in the mandible and often cross the midline.

Osteofibrous dysplasia (also known as ossifying fibroma) is a rare, benign non-neoplastic condition with no known cause. It is considered a fibrovascular defect. Campanacci described this condition in two leg bones, the tibia and fibula, and coined the term. This condition should be differentiated from Nonossifying fibroma and fibrous dysplasia of bone.

The color of peripheral ossifying fibromas ranges from red to pink, and is frequently ulcerated. It can be sessile or pedunculated with the size usually being less than 2 cm. Weeks or months may pass by before it is seen and diagnosed.

There is a gender difference with 66% of the disease occurring in females. The prevalence of peripheral ossifying fibromas is highest around 10 – 19 years of age. It appears only on the gingiva, more often on the maxilla rather than the mandible, and is frequently found in the area around incisors and canines. The adjacent teeth are usually not affected.

Peripheral ossifying fibromas appear microscopically as a combination of a mineralized product and fibrous proliferation. The mineralized portion may be bone, cementum-like, or dystrophic calcifications. Additionally, highly developed bone or cementum is more likely to be present when the peripheral ossifying fibroma has existed for a longer period of time.

Peripheral ossifying fibroma “a gingival nodule which is composed of a cellular fibroblastic connective tissue stroma which is associated with the formation of randomly dispersed foci of mineralised products, which consists of bone, cementum-like tissue, or a dystrophic calcification. The lesion is considered part of an ossifying fibroma, but that is usually considered to be a gnathic tumor. Because of its overwhelming incidence on the gingiva, the condition is associated with two other diseases, though not because they occur together. Instead, the three are associated with each other because they appear frequently on gingiva: pyogenic granuloma and peripheral giant cell granuloma. Some researchers believe peripheral ossifying fibromas to be related to pyogenic fibromas and, in some instances, are the result of a pyogenic granuloma which has undergone fibrosis and calcification.

The term "peripheral ossifying fibroma" has been criticized as this lesion is not related to the ossifying fibroma of bone and is not a fibroma. This term is used in America, however in Britain, this lesion would be termed a fibrous epulis containing bone.

The peripheral odontogenic fibroma is an uncommon gingival mass. It affects people across a large age range. It can be confused with the peripheral ossifying fibroma. In contrast to the peripheral ossifying fibroma, the peripheral odontogenic fibroma is a rare lesion.

No specific gender predilection while the ages of the patients ranged from 5 to 65 years.commonly seen in mandible than maxilla.

slow growing, solid, firmly attached gingival mass sometimes arising between teeth and sometimes displacing teeth.

consists of cellular fibrous connective tissue parenchyma with non neoplastic islands, strands of clouman or cuboidal odontogenic epithelium.

The afflicted may have relatively small amounts of pain that will quickly increase in severity over a time period of 6–12 weeks. The skin temperature around the bone may increase, a bony swelling may be evident, and movement may be restricted in adjacent joints.

Spinal lesions may cause quadriplegia and patients with skull lesions may have headaches.

The calcifying odotogenic cyst or the Gorlin cyst, now known in the WHO Classification of Tumours as the calcifying cystic odontogenic tumor, is a benign odontogenic tumor of cystic type most likely to affect the anterior areas of the jaws. It is most common in people in their second to third decades but can be seen at almost any age. On radiographs, the calcifying odontogenic cyst appears as a unilocular radiolucency (dark area). In one-third of cases, an impacted tooth is involved. Microscopically, there are many cells that are described as "ghost cells", enlarged eosinophilic epithelial cells without nuclei.

The ovarian fibroma, also fibroma, is a benign sex cord-stromal tumour.

Ovarian fibromas represent 4% of all ovarian neoplasms. They tend to occur mostly during perimenopause and postmenopause, the median age having been reported to be about 52 years, and they are rare in children. Lesions tend to be asymptomatic. If symptoms are present, the most common one is abdominal pain.

On gross pathology, they are firm and white or tan. On microscopic examination, there are intersecting bundles of spindle cells producing collagen.

There may be thecomatous areas (fibrothecoma). The presence of an ovarian fibroma can cause ovarian torsion in some cases.

Trichoblastomas are a cutaneous condition characterized by benign neoplasms of follicular germinative cells. Trichoblastic fibroma is a designation used to characterize small nodular trichoblastomas with conspicuous fibrocytic stroma, sometimes constituting over 50% of the lesion.

Fibrocartilaginous mesenchymoma of bone is (FCMB) is an extremely rare tumor first described in 1984. Fewer than 20 cases have been reported, with patient ages spanning from 9 to 25 years, though a case in a male infant aged 1 year and 7 months has been reported. Quick growth and bulky size are remarkable features of this tumor.

Giant-cell fibroma is a type of fibroma not associated with trauma or irritation. It can occur at any age and on a mucous membrane surface. The most common oral locations are on the gingiva of the mandible, tongue, and palate. It is a localized reactive proliferation of fibrous connective tissue.

Giant-cell fibroma (GCF) is a benign non-neoplastic lesion first described by Weathers and Callihan (1974). It occurs in the first three decades of life and predominates in females (Houston, 1982; Bakos, 1992). Clinically, the GCF presents as an asymptomatic, papillary and pedunculated lesion. The most predominant location is the mandibular gingiva (Houston, 1982; Bakos, 1992). Histologically, the GCF is distinctive, consisting of fibrous connective tissue without inflammation and covered with stratified squamous hyperplastic epithelium. The most characteristic histological feature is the presence of large spindle-shaped and stellate-shaped mononuclear cells and multinucleated cells. These cells occur in a variety of lesions, such as the fibrous papule of the nose, ungual fibroma, acral fibrokeratoma, acral angiofibroma and desmoplastic fibroblastoma (Swan, 1988; Pitt et al., 1993; Karabela-Bouropoulou et al., 1999; Jang et al., 1999).

Despite many studies, the nature of the stellated multinucleate and mononuclear cell is not clear (Weathers and Campbell, 1974; Regezi et al., 1987; Odell et al., 1994; Magnusson and Rasmusson, 1995).

Aneurysmal bone cyst, abbreviated ABC, is an osteolytic bone neoplasm characterized by several sponge-like blood or serum filled, generally non-endothelialized spaces of various diameters.

The term is a misnomer, as the lesion is neither an aneurysm nor a cyst.