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General treatment regimens have not changed much in the past 30 years, in part due to the lack of randomized clinical trials. Surgery is the treatment of choice if the tumor is determined to be resectable. Curettage is a commonly used technique. The situation is complicated in a patient with a pathological fracture. It may be best to immobilize the affected limb and wait for the fracture to heal before performing surgery.
Patients with tumors that are not amenable to surgery are treated with radiation therapy. However caution is employed since a majority of recurrent tumors with transformations to the malignant sarcoma phenotype have been in patients receiving radiotherapy for their primary benign lesion. Pharmacotherapy for GCTOB, includes bisphosphonates such as Zoledronate, which are thought to induce apoptosis in the MNGC fraction, preventing tumor-induced osteolysis. Indeed, "in vitro" studies have shown zolidronate to be effective in killing osteoclast-like cells. More recently, humanized monoclonal antibodies such as Denosumab targeting the RANK ligand have been employed in treatment of GCTOB in a phase II study. This is based on the notion that increased expression of RANK-ligands by stromal cells plays a role in tumor pathogenesis.
Chondroblastoma has not been known to spontaneously heal and the standard treatment is surgical curettage of the lesion with bone grafting. To prevent recurrence or complications it is important to excise the entire tumor following strict oncologic criteria. However, in skeletally immature patients intraoperative fluoroscopy may be helpful to avoid destruction of the epiphyseal plate. In patients who are near the end of skeletal growth, complete curettage of the growth plate is an option. In addition to curettage, electric or chemical cauterization (via phenol) can be used as well as cryotherapy and wide or marginal resection. Depending on the size of the subsequent defect, autograft or allograft bone grafts are the preferred filling materials. Other options include substituting polymethylmethacrylate (PMMA) or fat implantation in place of the bone graft. The work of Ramappa "et al" suggests that packing with PMMA may be a more optimal choice because the heat of polymerization of the cement is thought to kill any remaining lesion.
Both radiotherapy and chemotherapy are not commonly used. Radiotherapy has been implemented in chondroblastoma cases that are at increased risk of being more aggressive and are suspected of malignant transformation. Furthermore, radiofrequency ablation has been used, but is typically most successful for small chondroblastoma lesions (approximately 1.5 cm). Treatment with radiofrequency ablation is highly dependent on size and location due to the increased risk of larger, weight-bearing lesions being at an increased risk for articular collapse and recurrence.
Overall, the success and method of treatment is highly dependent upon the location and size of the chondroblastoma.
While chemotherapy, radiation therapy, curettage and liquid nitrogen have been effective in some cases of ameloblastoma, surgical resection or enucleation remains the most definitive treatment for this condition. In a detailed study of 345 patients, chemotherapy and radiation therapy seemed to be contraindicated for the treatment of ameloblastomas. Thus, surgery is the most common treatment of this tumor. Because of the invasive nature of the growth, excision of normal tissue near the tumor margin is often required. Some have likened the disease to basal cell carcinoma (a skin cancer) in its tendency to spread to adjacent bony and sometimes soft tissues without metastasizing. While rarely not a cancer that actually invades adjacent tissues, ameloblastoma is suspected to spread to adjacent areas of the jaw bone via marrow space. Thus, wide surgical margins that are clear of disease are required for a good prognosis. This is very much like surgical treatment of cancer. Often, treatment requires excision of entire portions of the jaw.
Radiation is ineffective in many cases of ameloblastoma. There have also been reports of sarcoma being induced as the result of using radiation to treat ameloblastoma. Chemotherapy is also often ineffective. However, there is some controversy regarding this and some indication that some ameloblastomas might be more responsive to radiation that previously thought.
The first route of treatment in Osteoblastoma is via medical means. Although necessary, radiation therapy (or chemotherapy) is controversial in the treatment of osteoblastoma. Cases of postirradiation sarcoma have been reported after use of these modalities. However, it is possible that the original histologic diagnosis was incorrect and the initial lesion was an osteosarcoma, since histologic differentiation of these two entities can be very difficult.
The alternative means of treatment consists of surgical therapy. The treatment goal is complete surgical excision of the lesion. The type of excision depends on the location of the tumor.
- For stage 1 and 2 lesions, the recommended treatment is extensive intralesional excision, using a high-speed burr. Extensive intralesional resections ideally consist of removal of gross and microscopic tumor and a margin of normal tissue.
- For stage 3 lesions, wide resection is recommended because of the need to remove all tumor-bearing tissue. Wide excision is defined here as the excision of tumor and a circumferential cuff of normal tissue around the entity. This type of complete excision is usually curative for osteoblastoma.
In most patients, radiographic findings are not diagnostic of osteoblastoma; therefore, further imaging is warranted. CT examination performed with the intravenous administration of contrast agent poses a risk of an allergic reaction to contrast material.
The lengthy duration of an MRI examination and a history of claustrophobia in some patients are limiting the use of MRI. Although osteoblastoma demonstrates increased radiotracer accumulation, its appearance is nonspecific, and differentiating these lesions from those due to other causes involving increased radiotracer accumulation in the bone is difficult. Therefore, bone scans are useful only in conjunction with other radiologic studies and are not best used alone.
Pain may be relieved by nonsteroidal anti-inflammatory drugs.
Treatment varies based on the health of the patient. If he/she is otherwise healthy and is not significantly bothered by the pain, the tumor is treated symptomatically with anti-inflammatories. If this therapy fails or the location of the tumor could lead to growth disturbances, scoliosis, or osteoarthritis, surgical or percutaneous ablation may be considered. If surgery is preferred, the individual may be referred to a podiatrist or an orthopedic surgeon to perform the procedure. Post-surgery therapy and strengthening may be needed, depending on the tumor location and health of the individual. While shown to be effective, surgical resection has many potential complications, including difficult intraoperative identification of the tumor, local recurrence from incomplete resection, and resection of weight bearing bone that can necessitate prolonged hospital stays and complicate recovery.
Recently, CT guided radiofrequency ablation has emerged as a less invasive alternative to surgical resection. 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, it has been shown in numerous studies to be less invasive and expensive, to result in less bone destruction and to have equivalent safety and efficacy to surgical techniques, with 66 to 96% of patients reporting freedom from symptoms. While initial success rates with RFA are high, symptom recurrence after RFA treatment has been reported, with some studies demonstrating a recurrence rate similar to that of surgical treatment. As of July 17, 2014, treatment with incisionless surgery utilizing an MRI to guide high-intensity ultrasound waves to destroy a benign bone tumor in the leg has been demonstrated.
Chemotherapy and radiotherapy are effective in some tumors (such as Ewing's sarcoma) but less so in others (such as chondrosarcoma).
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.
One of the major concerns is bone density and bone loss. Non-hormonal bisphosphonates increase bone strength and are available as once-a-week prescription pills. Metastron also known as strontium-89 chloride is an intravenous medication given to help with the pain and can be given in three month intervals. Generic Strontium Chloride Sr-89 Injection UPS, manufactured by Bio-Nucleonics Inc., it is the generic version of Metastron. Astra zantec is currently under review as to the benefits in bone cancer.
Radiotherapy is the main choice of treatment for both SPB and extramedullary plasmacytoma, and local control rates of >80% can be achieved. This form of treatment can be used with curative intent because plasmacytoma is a radiosensitive tumor. Surgery is an option for extramedullary plasmacytoma, but for cosmetic reasons it is generally used when the lesion is not present within the head and neck region.
The treatment for CGCG is thorough curettage. A referral is made to an oral surgeon. Recurrence ranges from 15%–20%. In aggressive tumors, three alternatives to surgery are undergoing investigation:
- corticosteroids;
- calcitonin (salmon calcitonin);
- interferon α-2a.
These therapeutic approaches provide positive possible alternatives for large lesions. The long term prognosis of giant-cell granulomas is good and metastases do not develop.
Depending on the pet's unique condition, there are several treatment options, including surgery, chemotherapy and radiation therapy. Treating the pain adequately is also of crucial importance to improve the pet's quality of life, especially if amputation is not performed.
Treatment depends upon the site and the extent of the disease. Clear cell sarcoma is usually treated with surgery in the first place in order to remove the tumor. The surgical procedure is then followed by radiation and sometimes chemotherapy. Few cases of clear cell sarcoma respond to chemotherapy. Several types of targeted therapy that may be of benefit to clear cell sarcoma patients are currently under investigation.
Curettage is performed on some patients, and is sufficient for inactive lesions. The recurrence rate with curettage is significant in active lesions, and marginal resection has been advised. Liquid nitrogen, phenol, methyl methacrylate are considered for use to kill cells at margins of resected cyst.
There is evidence that suppression of matrix metalloproteinase-2 may inhibit the local invasiveness of ameloblastoma, however, this was only demonstrated "in vitro". There is also some research suggesting that αβ integrin may participate in the local invasiveness of ameloblastomas.
A recent study discovered a high frequency of BRAF V600E mutations (15 of 24 samples, 63%) in solid/multicystic ameloblastoma. These data suggests drugs targeting mutant BRAF as potential novel therapies for ameloblastoma.
Removal of the mast cell tumor through surgery is the treatment of choice. Antihistamines, such as diphenhydramine, are given prior to surgery to protect against the effects of histamine released from the tumor. Wide margins (two to three centimeters) are required because of the tendency for the tumor cells to be spread out around the tumor. If complete removal is not possible due to the size or location, additional treatment, such as radiation therapy or chemotherapy, may be necessary. Prednisone is often used to shrink the remaining tumor portion. H2 blockers, such as cimetidine, protect against stomach damage from histamine. Vinblastine and CCNU are common chemotherapy agents used to treat mast cell tumors.
Toceranib and masitinib, examples of receptor tyrosine kinase inhibitors, are used in the treatment of canine mast cell tumors. Both were recently approved by the U.S. Food and Drug Administration (FDA) as dog-specific anticancer drugs.
Grade I or II mast cell tumors that can be completely removed have a good prognosis. One study showed about 23 percent of incompletely removed grade II tumors recurred locally. Any mast cell tumor found in the gastrointestinal tract, paw, or on the muzzle has a guarded prognosis. Previous beliefs that tumors in the groin or perineum carried a worse prognosis have been discounted. Tumors that have spread to the lymph nodes or other parts of the body have a poor prognosis. Any dog showing symptoms of mastocytosis or with a grade III tumor has a poor prognosis. Dogs of the Boxer breed have a better than average prognosis because of the relatively benign behavior of their mast cell tumors. Multiple tumors that are treated similarly to solitary tumors do not seem to have a worse prognosis.
Mast cell tumors do not necessarily follow the histological prognosis. Further prognostic information can be provided by AgNOR stain of histological or cytological specimen. Even then, there is a risk of unpredictable behavior.
A complete radical, surgical, "en bloc" resection of the cancer, is the treatment of choice in osteosarcoma. Although about 90% of patients are able to have limb-salvage surgery, complications, particularly infection, prosthetic loosening and non-union, or local tumor recurrence may cause the need for further surgery or amputation.
Mifamurtide is used after a patient has had surgery to remove the tumor and together with chemotherapy to kill remaining cancer cells to reduce the risk of cancer recurrence. Also, the option to have rotationplasty after the tumor is taken out exists.
Patients with osteosarcoma are best managed by a medical oncologist and an orthopedic oncologist experienced in managing sarcomas. Current standard treatment is to use neoadjuvant chemotherapy (chemotherapy given before surgery) followed by surgical resection. The percentage of tumor cell necrosis (cell death) seen in the tumor after surgery gives an idea of the prognosis and also lets the oncologist know if the chemotherapy regimen should be altered after surgery.
Standard therapy is a combination of limb-salvage orthopedic surgery when possible (or amputation in some cases) and a combination of high-dose methotrexate with leucovorin rescue, intra-arterial cisplatin, adriamycin, ifosfamide with mesna, BCD (bleomycin, cyclophosphamide, dactinomycin), etoposide, and muramyl tripeptide. Rotationplasty may be used. Ifosfamide can be used as an adjuvant treatment if the necrosis rate is low.
Despite the success of chemotherapy for osteosarcoma, it has one of the lowest survival rates for pediatric cancer. The best reported 10-year survival rate is 92%; the protocol used is an aggressive intra-arterial regimen that individualizes therapy based on arteriographic response. Three-year event-free survival ranges from 50% to 75%, and five-year survival ranges from 60% to 85+% in some studies. Overall, 65–70% patients treated five years ago will be alive today. These survival rates are overall averages and vary greatly depending on the individual necrosis rate.
Filgrastim or pegfilgrastim help with white blood cell counts and neutrophil counts. Blood transfusions and epoetin alfa help with anemia. Computational analysis on a panel of Osteosarcoma cell lines identified new shared and specific therapeutic targets (proteomic and genetic) in Osteosarcoma, while phenotypes showed an increased role of tumor microenvironments.
As the condition is quite rare, opinions among experts about how to treat OKCs differ.
Treatment options:
- Wide (local) surgical excision.
- Marsupialization - the surgical opening of the (OKC) cavity and a creation of a marsupial-like pouch, so that the cavity is in contact with the outside for an extended period, e.g. three months.
- Curettage (simple excision & scrape-out of cavity).
- Peripheral ostectomy after curettage and/or enucleation.
- Simple excision.
- Carnoy's solution - usually used in conjunction with excision.
- Enucleation and cryotherapy
When the lesion is localized, it is generally curable. However, long-term survival for children with advanced disease older than 18 months of age is poor despite aggressive multimodal therapy (intensive chemotherapy, surgery, radiation therapy, stem cell transplant, differentiation agent isotretinoin also called 13-"cis"-retinoic acid, and frequently immunotherapy with anti-GD2 monoclonal antibody therapy).
Biologic and genetic characteristics have been identified, which, when added to classic clinical staging, has allowed patient assignment to risk groups for planning treatment intensity. These criteria include the age of the patient, extent of disease spread, microscopic appearance, and genetic features including DNA ploidy and N-myc oncogene amplification (N-myc regulates microRNAs), into low, intermediate, and high risk disease. A recent biology study (COG ANBL00B1) analyzed 2687 neuroblastoma patients and the spectrum of risk assignment was determined: 37% of neuroblastoma cases are low risk, 18% are intermediate risk, and 45% are high risk. (There is some evidence that the high- and low-risk types are caused by different mechanisms, and are not merely two different degrees of expression of the same mechanism.)
The therapies for these different risk categories are very different.
- Low-risk disease can frequently be observed without any treatment at all or cured with surgery alone.
- Intermediate-risk disease is treated with surgery and chemotherapy.
- High-risk neuroblastoma is treated with intensive chemotherapy, surgery, radiation therapy, bone marrow / hematopoietic stem cell transplantation, biological-based therapy with 13-"cis"-retinoic acid (isotretinoin or Accutane) and antibody therapy usually administered with the cytokines GM-CSF and IL-2.
With current treatments, patients with low and intermediate risk disease have an excellent prognosis with cure rates above 90% for low risk and 70–90% for intermediate risk. In contrast, therapy for high-risk neuroblastoma the past two decades resulted in cures only about 30% of the time. The addition of antibody therapy has raised survival rates for high-risk disease significantly. In March 2009 an early analysis of a Children's Oncology Group (COG) study with 226 high-risk patients showed that two years after stem cell transplant 66% of the group randomized to receive ch14.18 antibody with GM-CSF and IL-2 were alive and disease-free compared to only 46% in the group that did not receive the antibody. The randomization was stopped so all patients enrolling on the trial will receive the antibody therapy.
Chemotherapy agents used in combination have been found to be effective against neuroblastoma. Agents commonly used in induction and for stem cell transplant conditioning are platinum compounds (cisplatin, carboplatin), alkylating agents (cyclophosphamide, ifosfamide, melphalan), topoisomerase II inhibitor (etoposide), anthracycline antibiotics (doxorubicin) and vinca alkaloids (vincristine). Some newer regimens include topoisomerase I inhibitors (topotecan and irinotecan) in induction which have been found to be effective against recurrent disease.
They are benign lesions and malignant degeneration is rare. They are usually treated with curettage which however have a high recurrence rate of 25%. As such if an en-bloc resection is possible this is advisable
Two related drugs have been shown to shrink or stabilize subependymal giant cell tumors: rapamycin and everolimus. These both belong to the mTOR inhibitor class of immunosuppressants, and are both contraindicated in patients with severe infections.
Rapamycin showed efficacy in five cases of SEGA in TSC patients, shrinking their tumor volumes by an average of 65%. However, after the drug was stopped, the tumors regrew.
Everolimus, which has a similar structure as rapamycin, but with slightly increased bioavailability and shorter half-life, was studied in 28 patients with SEGA. There was a significant reduction in SEGA size in 75% of the patients, and a mild improvement in their seizures. Everolimus was approved for the treatment of SEGA by the US Food and Drug Administration (FDA) in October, 2010.
Wide excision is the treatment of choice, although attempting to preserve hearing. Based on the anatomic site, it is difficult to completely remove, and so while there is a good prognosis, recurrences or persistence may be seen. There is no metastatic potential. Patients who succumb to the disease, usually do so because of other tumors within the von Hippel-Lindau complex rather than from this tumor.
Almost all patients require multidrug chemotherapy (often including ifosfamide and etoposide), as well as local disease control with surgery and/or radiation. An aggressive approach is necessary because almost all patients with apparently localized disease at the time of diagnosis actually have asymptomatic metastatic disease.
Treatment often consists of neoadjuvant chemotherapy, which may include vincristine, doxorubicin, and cyclophosphamide with ifosfamide and etoposide. After about three months of chemotherapy, the remaining tumor is surgically resected, irradiated, or both. The surgical resection may involve limb salvage or amputation. Complete excision at the time of biopsy may be performed if malignancy is confirmed at the time it is examined.
Treatment lengths vary depending on location and stage of the disease at diagnosis. Radical chemotherapy may be as short as six treatments at 3-week cycles, but most patients undergo chemotherapy for 6–12 months and radiation therapy for 5–8 weeks.
Radiotherapy has been used for localized disease. The tumor has a unique property of being highly sensitive to radiation, sometimes acknowledged by the phrase "melting like snow", but the main drawback is that it recurs dramatically after some time. Antisense oligodeoxynucleotides have been proposed as possible treatment by down-regulating the expression of the oncogenic fusion protein associated with the development of Ewing's sarcoma resulting from the EWS-ETS gene translocation. In addition, the synthetic retinoid derivative fenretinide (4-hydroxy(phenyl)retinamide) has been reported to induce high levels of cell death in Ewing's sarcoma cell lines "in vitro" and to delay growth of xenografts in "in vivo" mouse models.
A number of tumors have giant cells, but are not true benign giant-cell tumors. These include, aneurysmal bone cyst, chondroblastoma, simple bone cyst, osteoid osteoma, osteoblastoma, osteosarcoma, giant-cell reparative granuloma, and brown tumor of hyperparathyroidism.
Chemotherapy with topotecan and cyclophosphamide is frequently used in refractory setting and after relapse.
A NIH Consensus Conference report in 1999 recommends that any SEGA that is growing or causing symptoms should be surgically removed. Tumors are also removed in cases where a patient is suffering from a high seizure burden. If a tumor is rapidly growing or causing symptoms of hydrocephalus, deferring surgery may lead to vision loss, need for ventricular shunt, and ultimately death. Total removal of the tumor is curative.
Surgery to remove intraventricular tumors also carries risks of complications or death. Potential complications include transient memory impairment, hemiparesis, infection, chronic ventriculoperitoneal shunt placement, stroke, and death.
Usually, treatment of a lipoma is not necessary, unless the tumor becomes painful or restricts movement. They are usually removed for cosmetic reasons, if they grow very large, or for histopathology to check that they are not a more dangerous type of tumor such as a liposarcoma. This last point can be important as the characteristics of a "bump" are not known until after it is removed and medically examined.
Lipomas are normally removed by simple excision. The removal can often be done under local anaesthetic, and takes less than 30 minutes. This cures the great majority of cases, with about 1–2% of lipomas recurring after excision. Liposuction is another option if the lipoma is soft and has a small connective tissue component. Liposuction typically results in less scarring; however, with large lipomas it may fail to remove the entire tumor, which can lead to regrowth.
New methods under development are supposed to remove the lipomas without scarring. One is removal by injecting compounds that trigger lipolysis, such as steroids or phosphatidylcholine.