A bone tumor is an neoplastic of tissue in bone, traditionally classified as benign (benign) or malignant (malignant).[ Cancerous bone tumors usually originate from a cancer in another part of the body such as from Lung cancer, Breast cancer, Thyroid cancer, kidney cancer and Prostate cancer.][ 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.][
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Diagnosis is generally by X-ray and other Radiography such as CT scan, MRI, PET scan and bone scintigraphy.[ Blood tests might include a complete blood count, inflammatory markers, serum electrophoresis, PSA, kidney function and liver function.][ Urine may be tested for Bence Jones protein.][ For confirmation of diagnosis, a biopsy for Histopathology might be required.][
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The most common bone tumor is a non-ossifying fibroma.[ Average five-year survival in the United States after being diagnosed with bone and joint cancer is 67%.]
Classification
Bone tumors are traditionally classified as benign (benign) or malignant (malignant).[ Several features of bone tumors and soft tissue tumors overlap.]
Bone tumors may be classified as "primary tumors", which originate in bone or from bone-derived cells and tissues, and "" which originate in other sites and spread (metastasis) to the skeleton. of the Prostate cancer, Breast cancer, Lung cancer, Thyroid cancer, and Kidney cancer are the carcinomas that most commonly metastasize to bone. Secondary malignant bone tumors are estimated to be 50 to 100 times as common as primary bone cancers.
Primary bone tumors
Primary tumors of bone can be divided into benign and . Common benign bone tumors may be neoplasia, developmental, Physical trauma, infection, or inflammation in etiology. Some benign tumors are not true neoplasms, but rather, represent , namely the osteochondroma. The most common locations for many primary tumors, both benign and malignant include the distal femur and proximal tibia (around the knee joint). Examples of benign bone tumors include osteoma, osteoid osteoma, osteochondroma, osteoblastoma, enchondroma, giant cell tumor of bone and aneurysmal bone cyst.
Malignant primary bone tumors, known as , include osteosarcoma, chondrosarcoma, Ewing sarcoma, fibrosarcoma, and other types. While malignant fibrous histiocytoma (MFH) - now generally called "pleomorphic undifferentiated sarcoma" - primary in bone is known to occur occasionally,[Jeon DG, Song WS, Kong CB, Kim JR, Lee SY. MFH of Bone and Osteosarcoma Show Similar Survival and Chemosensitivity. Clin Orthop Rel Res 469;584-90.] current paradigms tend to consider MFH a wastebasket diagnosis, and the current trend is toward using specialized studies (i.e. Genetics and immunohistochemical tests) to classify these undifferentiated tumors into other tumor classes. Multiple myeloma is a hematology cancer, originating in the bone marrow, which also frequently presents as one or more bone lesions.
Germ cell tumors, including teratoma, often present and originate in the midline of the sacrum, coccyx, or both. These sacrococcygeal teratomas are often relatively amenable to treatment.
Secondary bone tumors
Secondary bone tumors are metastasis which have spread from other organs, most commonly carcinomas of the breast, lung, and prostate. Rarely, primary bone malignancies such as osteosarcoma may also spread to other bones.
Signs and symptoms
Clinical features of a bone tumor depend on the type of tumor and which part of which bone is affected.[
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There may be a lump, with or without pain.[ Pain may increase with the growth of the tumor and may be worse at night and at rest.][ A bone tumor might present with an unexplained broken bone; with little or no trauma.][ If the tumor presses a nerve, neurological signs may be present.][ Sometimes there are no symptoms and the tumour is found when investigating another problem.][
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Diagnosis
A bone tumour may be felt on examination, following which a plain X-ray is usually carried out.[ Urine may be sent for Bence Jones protein.][ Other Radiography that might be requested include a CT scan, MRI, PET scan and bone scintigraphy. For confirmation of diagnosis, a biopsy for Histopathology might be required, using either a needle or by incision (open biopsy).]
===Staging===
Treatment
Treatment of bone tumors is dependent on the type of tumor.[ Generally, noncancerous bone tumors may be observed for changes and surgery offered if there is pain or pressure effects on neighbouring body parts. Surgical resection with or without cytotoxic drugs may be considered.][ Treatment typically involves a multidisciplinary approach combining surgery, chemotherapy, and radiation therapy, tailored to the specific type, stage, and location of the cancer. Despite advances in medical technology and treatment protocols, bone cancer continues to present significant challenges for patients and healthcare providers alike.
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Chemotherapy and radiotherapy
Chemotherapy and radiotherapy are effective in some tumors (such as Ewing's sarcoma) but less so in others (such as chondrosarcoma).[ Bone tumor at Mount Sinai Hospital, New York]
There is a variety of chemotherapy treatment protocols for bone tumors. The protocol with the best-reported survival in children and adults is an intra-arterial protocol where tumor response is tracked by serial arteriogram. When tumor response has reached >90% necrosis surgical intervention is planned.[ 10 year survival in Pediatric Osteosarcoma][ Survival in Adult Osteosarcoma and MFH of Bone]
Medication
One of the major concerns is bone density and bone loss. Non-hormonal increase bone strength and are available as once-a-week prescription pills. Strontium-89 chloride is an intravenous medication given to help with the pain and can be given in three-month intervals.
Surgical treatment
Treatment for some bone cancers may involve surgery, such as limb amputation, or limb sparing surgery (often in combination with chemotherapy and radiation therapy). Limb sparing surgery, or limb salvage surgery, means the limb is spared from amputation. Instead of amputation, the affected bone is removed and replaced in one of two ways: (a) bone graft, in which bone is taken from elsewhere on the body or (b) artificial bone is put in. In upper leg surgeries, limb salvage prostheses are available.
There are other joint preservation surgical reconstruction options, including allograft, tumor-devitalized autograft, vascularized fibula graft, distraction osteogenesis, and custom-made implants.
Thermal ablation techniques
Over the past two decades, CT guided radiofrequency ablation has emerged as a less invasive alternative to surgical resection in the care of benign bone tumors, most notably . In this technique, which can be performed under conscious sedation, a RF probe is introduced into the tumor nidus through a cannulated needle under CT guidance and heat is applied locally to destroy tumor cells. Since the procedure was first introduced for the treatment of osteoid osteomas in the early 1990s,
Thermal ablation techniques are also increasingly being used in the palliative treatment of painful metastatic bone disease. Currently, external beam radiation therapy is the standard of care for patients with localized bone pain due to metastatic disease. Although the majority of patients experience complete or partial relief of pain following radiation therapy, the effect is not immediate and has been shown in some studies to be transient in more than half of patients.
Prognosis
The outlook depends on the type of tumor. The outcome is expected to be good for people with noncancerous (benign) tumors, although some types of benign tumors may eventually become cancerous (malignant). With malignant bone tumors that have not spread, most patients achieve a cure, but the cure rate depends on the type of cancer, location, size, and other factors.
Epidemiology
Bone tumors that originate from bone are very rare and account for around 0.2% of all tumors.[
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History
The earliest known bone tumor was an osteosarcoma in a foot bone belonging to a person who died in Swartkrans Cave, South Africa, between 1.6 and 1.8 million years ago.
Other animals
Bones are a common site for tumors in cats and dogs.
