A juvenile active ossifying fibroma is a benign fibro-osseous neoplasm composed of mixture of stroma and bone characterized by rapid and destructive growth.
This tumor has gone by several names in the past, but active ossifying fibroma is similar to juvenile active ossifying fibroma, except it does not develop in young patients. Aggressive psammomatoid ossifying fibroma is still employed by some, but is to be discouraged. [1]
Most patients are asymptomatic, and come to clinical attention when a mass is discovered incidentally on routine dental X-rays. [2] When patients are symptomatic, they present with non-specific symptoms, such as chronic sinusitis, rhinorrhea, obstruction, pain, facial enlargement and possibly visual changes. [3]
When performing imaging studies, bone windows in computed tomography studies are the best. The lesion is usually identified as a well demarcated, expansile mass with an ossified rim at the periphery. Calcifications are noted throughout. MRI shows a variable finding depending on T1 or T2 weighted images, dependent on the amount of bone to fibrous connective tissue ratio. [2]
The tumors are described as "shelling out" by the surgeon, which gives a well-circumscribed, smooth surface of tan, white, firm-gritty material. The tumors range in size from a few millimeters up to 10 cm. [1] [3]
By microscopic evaluation, the tumors are composed of a variably cellular stroma make up of spindled to stellate fibroblast-like cells. Within this stroma, are numerous small, rounded, mineralized collagenous ossicles and immature osteoid. Many times the curved-shaped bone fragments have a collagenous rim around them. Ossicles may fuse to form much large mineralizations. Cementum-like psammomatous bodies (cementicles) may also be present. Osteoblastic rimming is not uncommon. Occasionally, giant cells and even mitoses are seen. [1] [3]
Active ossifying fibroma must be separated from fibrous dysplasia, cementoblastoma, and meningioma. This type of separation must be made with the aid of imaging studies, and should not be done by histology examination only. [1]
It is important to get complete excision as early in the disease process as possible. Once the lesion is removed, the prognosis is excellent. However, if the lesion is incompletely excised, recurrences may be seen in up to 60% of patients. The recurrences are highest in sinus tumors. [3]
This tumor is far less common than conventional ossifying fibroma, and is considered a rare tumor. Patients usually come to clinical attention when <15 years of age, but a wide age range (3 months to 70 years) can be affected. Both genders are affected equally, with the paranasal sinuses most commonly affected. Specifically, the ethmoid sinus is affected most often, followed by frontal sinus, maxillary sinus and sphenoid sinus. The maxilla is the second most common location after the paranasal sinuses, while the mandible and temporal bone are infrequently affected. This tumor does not frequently extracranial sites nor soft tissues sites. [1] [3]
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, thyroid, kidney and prostate. There may be a lump, pain, or neurological signs from pressure. A bone tumor might present with a pathologic fracture. Other symptoms may include fatigue, fever, weight loss, anemia and nausea. Sometimes there are no symptoms and the tumour is found when investigating another problem.
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.
Ameloblastoma is a rare, benign or cancerous tumor of odontogenic epithelium much more commonly appearing in the lower jaw than the upper jaw. It was recognized in 1827 by Cusack. This type of odontogenic neoplasm was designated as an adamantinoma in 1885 by the French physician Louis-Charles Malassez. It was finally renamed to the modern name ameloblastoma in 1930 by Ivey and Churchill.
In medicine, a desmoplastic fibroma is a benign, but locally aggressive, fibrous and rare tumor of the bone, affecting children and young adults, potentially resulting in cortical bone destruction. It usually affects craniofacial bones, mandible most frequently, long bones. The World Health Organization, 2020, reclassified these tumors as specific benign tumors in the category of fibroblastic and myofibroblastic tumors.
A peripheral ossifying fibroma, also known as ossifying fibrous epulis, is “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 jaw 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.
Giant-cell fibroma is a benign localized fibrous mass. It often mimics other fibroepithelial growths and can be distinguished by its histopathology. The exact cause of giant-cell fibromas is unknown however there is no evidence to show that it can be caused by irritation. Giant-cell fibromas can be removed by surgical incision, electrosurgery, or laser excision.
Calcifying odontogenic cyst (COC) is a rare developmental lesion that comes from odontogenic epithelium. It is also known as a calcifying cystic odontogenic tumor, which is a proliferation of odontogenic epithelium and scattered nest of ghost cells and calcifications that may form the lining of a cyst, or present as a solid mass.
An ameloblastic fibroma is a fibroma of the ameloblastic tissue, that is, an odontogenic tumor arising from the enamel organ or dental lamina. It may be either truly neoplastic or merely hamartomatous. In neoplastic cases, it may be labeled an ameloblastic fibrosarcoma in accord with the terminological distinction that reserves the word fibroma for benign tumors and assigns the word fibrosarcoma to malignant ones. It is more common in the first and second decades of life, when odontogenesis is ongoing, than in later decades. In 50% of cases an unerupted tooth is involved.
The odontogenic myxoma is an uncommon benign odontogenic tumor arising from embryonic connective tissue associated with tooth formation. As a myxoma, this tumor consists mainly of spindle shaped cells and scattered collagen fibers distributed through a loose, mucoid material.
Chondroblastoma is a rare, benign, locally aggressive bone tumor that typically affects the epiphyses or apophyses of long bones. It is thought to arise from an outgrowth of immature cartilage cells (chondroblasts) from secondary ossification centers, originating from the epiphyseal plate or some remnant of it.
Cementoma is an odontogenic tumor of cementum. It is usually observed as a benign spherical mass of hard tissue fused to the root of a tooth. It is found most commonly in the mandible in the region of the lower molar teeth, occurring between the ages of 8 and 30 in both sexes with equal frequency. It causes distortion of surrounding areas but is usually a painless growth, at least initially. Considerable thickening of the cementum can often be observed. A periapical form is also recognized. Cementoma is not exclusive to the mandible as it can infrequently occur in the maxilla and other parts of the body such as the long bones.
Angiofibroma (AGF) is a descriptive term for a wide range of benign skin or mucous membrane lesions in which individuals have:
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.
A bone cyst or geode is a cyst that forms in bone.
A non-ossifying fibroma (NOF) is a benign bone tumor of the osteoclastic giant cell-rich tumor type. It generally occurs in the metaphysis of long bones in children and adolescents. Typically, there are no symptoms unless there is a fracture. It can occur as part of a syndrome such as when multiple non-ossifying fibromas occur in neurofibromatosis, or Jaffe–Campanacci syndrome in combination with cafe-au-lait spots, mental retardation, hypogonadism, eye and cardiovascular abnormalities.
Epulis is any tumor like enlargement situated on the gingival or alveolar mucosa. The word literally means "(growth) on the gingiva", and describes only the location of the mass and has no further implications on the nature of the lesion. There are three types: fibromatous, ossifying and acanthomatous. The related term parulis refers to a mass of inflamed granulation tissue at the opening of a draining sinus on the alveolus over the root of an infected tooth. Another closely related term is gingival enlargement, which tends to be used where the enlargement is more generalized over the whole gingiva rather than a localized mass.
Nuchal-type fibroma is a rare benign proliferation involving the dermis and subcutaneous tissues, that is a collection of dense, hypocellular bundles of collagen with entrapped adipocytes and increased numbers of small nerves. It is no longer called a nuchal fibroma, but instead a "nuchal-type fibroma" since it develops in other anatomic sites. There is no known etiology. The World Health Organization in 2020 classified nuchal fibromas as a specific tumor form in the category of benign fibroblastic and myofibroblastic tumors.
Fibrocartilaginous mesenchymoma of bone (FCMB) is an extremely rare tumor first described in 1984. About 26 cases have been reported in literature, 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.
Fibroblastic and myofibroblastic tumors (FMTs) develop from the mesenchymal stem cells which differentiate into fibroblasts and/or the myocytes/myoblasts that differentiate into muscle cells. FMTs are a heterogeneous group of soft tissue neoplasms. 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. 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. The World Health Organization further classified FMTs into four tumor forms based on their varying levels of aggressiveness: benign, intermediate, intermediate, and malignant.
The ameloblastic fibro-odontoma (AFO) is essentially a benign tumor with the features characteristic of ameloblastic fibroma along with enamel and dentin. Though it is generally regarded as benign, there have been cases of its malignant transformation into ameloblastic fibrosarcoma and odontogenic sarcoma. Cahn LR and Blum T, believed in "maturation theory", which suggested that AFO was an intermediate stage and eventually developed during the period of tooth formation to a complex odontoma thus, being a hamartoma.
Lester D. R. Thompson; Bruce M. Wenig (2011). Diagnostic Pathology: Head and Neck: Published by Amirsys. Hagerstown, MD: Lippincott Williams & Wilkins. pp. 6:60–1. ISBN 978-1-931884-61-7.