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.
Hereditary multiple osteochondromas (HMO), also known as hereditary multiple exostoses, is a disorder characterized by the development of multiple benign osteocartilaginous masses (exostoses) in relation to the ends of long bones of the lower limbs such as the femurs and tibias and of the upper limbs such as the humeri and forearm bones. They are also known as osteochondromas. Additional sites of occurrence include on flat bones such as the pelvic bone and scapula. The distribution and number of these exostoses show a wide diversity among affected individuals. Exostoses usually present during childhood. The vast majority of affected individuals become clinically manifest by the time they reach adolescence. A small percentage of affected individuals are at risk for development of sarcomas as a result of malignant transformation. The incidence of hereditary multiple exostoses is around 1 in 50,000 individuals. Hereditary multiple osteochondromas is the preferred term used by the World Health Organization.
Chondrosarcoma is a bone sarcoma, a primary cancer composed of cells derived from transformed cells that produce cartilage. A chondrosarcoma is a member of a category of tumors of bone and soft tissue known as sarcomas. About 30% of bone sarcomas are chondrosarcomas. It is resistant to chemotherapy and radiotherapy. Unlike other primary bone sarcomas that mainly affect children and adolescents, a chondrosarcoma can present at any age. It more often affects the axial skeleton than the appendicular skeleton.
A benign tumor is a mass of cells (tumor) that does not invade neighboring tissue or metastasize. Compared to malignant (cancerous) tumors, benign tumors generally have a slower growth rate. Benign tumors have relatively well differentiated cells. They are often surrounded by an outer surface or stay contained within the epithelium. Common examples of benign tumors include moles and uterine fibroids.
Fibroadenomas are benign breast tumours characterized by an admixture of stromal and epithelial tissue. Breasts are made of lobules and ducts. These are surrounded by glandular, fibrous and fatty tissues. Fibroadenomas develop from the lobules. The glandular tissue and ducts grow over the lobule to form a solid lump.
An exostosis, also known as a bone spur, is the formation of new bone on the surface of a bone. Exostoses can cause chronic pain ranging from mild to debilitatingly severe, depending on the shape, size, and location of the lesion. It is most commonly found in places like the ribs, where small bone growths form, but sometimes larger growths can grow on places like the ankles, knees, shoulders, elbows and hips. Very rarely are they on the skull.
Enchondroma is a type of benign bone tumor belonging to the group of cartilage tumors. There may be no symptoms, or it may present typically in the short tubular bones of the hands with a swelling, pain or pathological fracture.
Osteochondromas are the most common benign tumors of the bones. The tumors take the form of cartilage-capped bony projections or outgrowth on the surface of bones exostoses. It is characterized as a type of overgrowth that can occur in any bone where cartilage forms bone. Tumors most commonly affect long bones about the knee and in the forearm. Additionally, flat bones such as the pelvis and scapula may be affected. Hereditary multiple exostoses usually present during childhood. Yet, the vast majority of affected individuals become clinically manifest by the time they reach adolescence. Osteochondromas occur in 3% of the general population and represent 35% of all benign tumors and 8% of all bone tumors. The majority of these tumors are solitary non-hereditary lesions and approximately 15% of osteochondromas occur as hereditary multiple exostoses preferably known as hereditary multiple osteochondromas (HMOs). Osteochondromas do not result from injury and the exact cause remains unknown. Recent research has indicated that multiple osteochondromas is an autosomal dominant inherited disease. Germ line mutations in EXT1 and EXT2 genes located on chromosomes 8 and 11 have been associated with the cause of the disease. The treatment choice for osteochondroma is surgical removal of solitary lesion or partial excision of the outgrowth, when symptoms cause motion limitations or nerve and blood vessel impingements. In hereditary multiple exostoses the indications of surgery are based upon multiple factors that are taken collectively, namely: patient's age, tumor location and number, accompanying symptomatology, esthetic concerns, family history and underlying gene mutation. A variety of surgical procedures have been employed to remedy hereditary multiple exostoses such as osteochondroma excision, bone lengthening, corrective osteotomy and hemiepiphysiodesis. Sometimes a combination of the previous procedures is used. The indicators of surgical success in regard to disease and patient characteristics are greatly disputable. Because most studies of hereditary multiple exostoses are retrospective and of limited sample size with missing data, the best evidence for each of the currently practiced surgical procedures is lacking.
Metachondromatosis is an autosomal dominant, incompletely penetrant genetic disease affecting the growth of bones, leading to exostoses primarily in the hands and feet as well as enchondromas of long bone metaphyses and iliac crests. This syndrome affects mainly tubular bones, though it can also involve the vertebrae, small joints, and flat bones. The disease is thought to affect exon 4 of the PTPN11 gene. Metachondromatosis is believed to be caused by an 11 base pair deletion resulting in a frameshift and nonsense mutation. The disease was discovered and named in 1971 by Pierre Maroteaux, a French physician, when he observed two families with skeletal radiologic features with exostoses and Ollier disease. The observation of one family with five affected people led to the identification of the disease as autosomal dominant. There have been less than 40 cases of the disease reported to date.
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 and exceeds in frequency any other tumor or tumor-like lesion in this group of tumors.
Aneurysmal bone cyst (ABC) is a non-cancerous bone tumor composed of multiple varying sizes of spaces in a bone which are filled with blood. The term is a misnomer, as the lesion is neither an aneurysm nor a cyst. It generally presents with pain and swelling in the affected bone. Pressure on neighbouring tissues may cause compression effects such as neurological symptoms.
Osteoblastoma is an uncommon osteoid tissue-forming primary neoplasm of the bone.
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. AGF lesions share common macroscopic and microscopic appearances. Grossly, AGF lesions consist of multiple papules, one or more skin-colored to erythematous, dome-shaped nodules, or usually just a single tumor. Microscopically, they consist of spindle-shaped and stellate-shaped cells centered around dilated and thin-walled blood vessels in a background of coarse bundles of collagen. Angiofibromas have been divided into different types but commonly a specific type was given multiple and very different names in different studies. The following list gives a brief description of the AFG types and their alternate names.
Cartilage tumors, also known as chondrogenic tumors, are a type of bone tumor that develop in cartilage, and are divided into non-cancerous, cancerous and intermediate locally aggressive types.
Trevor disease, also known as dysplasia epiphysealis hemimelica and Trevor's disease, is a congenital bone developmental disorder. There is 1 case per million population. The condition is three times more common in males than in females.
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.
Koenen's tumor (KT), also commonly termed periungual angiofibroma, is a subtype of the angiofibromas. Angiofibromas are benign papule, nodule, and/or tumor lesions that are separated into various subtypes based primarily on the characteristic locations of their lesions. KTs are angiofibromas that develop in and under the toenails and/or fingernails. KTs were once considered as the same as another subtype of the angiofibromas viz., acral angiofibromas. While the literature may still sometimes regard KTs as acral angiofibromas, acral angiofibromas are characteristically located in areas close to but not in the toenails and fingernails as well as in the soles of the feet and palms of the hands. KTs are here regarded as distinct from acral angiofibromas.
Bizarre parosteal osteochondromatous proliferation (BPOP), also known as Nora's lesion, is a type of non-cancerous bone tumor belonging to the group of cartilage tumors. It is generally seen in the tubular bones of the hands and feet, where it presents with a rapidly enlarging painless lump in a finger or toe.
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.
Extraskeletal Ewing sarcoma (EES), is a cancer of soft tissue, a type of Ewing sarcoma that does not arise from bone.
