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There is no way to reverse VHL mutations, but early recognition and treatment of specific manifestations of VHL can substantially decrease complications and improve quality of life. For this reason, individuals with VHL disease are usually screened routinely for retinal angiomas, CNS hemangioblastomas, clear-cell renal carcinomas and pheochromocytomas. CNS hemangioblastomas are usually surgically removed if they are symptomatic. Photocoagulation and cryotherapy are usually used for the treatment of symptomatic retinal angiomas, although anti-angiogenic treatments may also be an option. Renal tumours may be removed by a partial nephrectomy or other techniques such as radiofrequency ablation.
Uterine fibroids can be treated with the same methods like sporadic uterine fibroids including antihormonal treatment, surgery or embolisation. Substantially elevated risk of progression to or independent development of uterine leiomyosarcoma has been reported which may influence treatment methods.
The predisposition to renal cell cancer calls for screening and, if necessary, urological management.
The skin lesions may be difficult to treat as they tend to recur after excision or destructive treatment. Drugs which affect smooth muscle contraction, such as doxazosin, nitroglycerine, nifedipine and phenoxybenzamine, may provide pain relief.
Topical lidocaine patches have been reported to decrease in severity and frequency of pain cutaneous leiomyomas.
Treatment is mainly surgical; radiotherapy or chemotherapy is usually an indication of relapse. Head and neck desmoid fibromatosis is a serious condition due to local aggression, specific anatomical patterns and the high rate of relapse. For children surgery is particularly difficult, given the potential for growth disorders.
Treatment includes prompt radical excision with a wide margin and/or radiation. Despite their local infiltrative and aggressive behavior, mortality is minimal to nonexistent for peripheral tumours. In intra-abdominal fibromatosis associated with Familial adenomatous polyposis (FAP), surgery is avoided if possible due to high rates of recurrence within the abdomen carrying significant morbidity and mortality. Conversely, for intra-abdominal fibromatosis without evidence of FAP extensive surgery may still be required for local symptoms, but the risk of recurrence is low.
Prophylactic mastectomy to reduce the risk of breast cancer is an option.
Treatment:wide excision taking 8mm normal tissue as this is locally malignant. For recurrence radiotherapy is given
The main treatment modalities are surgery, embolization and radiotherapy.
Treatment may consist of watching and waiting, complete surgical removal, radiation therapy, antiestrogens (ex. Tamoxifen), NSAIDs, chemotherapy or microwave ablation.
Patients with desmoid tumors should be evaluated by a multi-disciplinary team of surgeons, medical oncologists, radiation oncologists, geneticists and nurses. There is no cure for desmoid tumors and when possible patients are encouraged to enlist in clinical trials.
A biopsy is always indicated as the definitive method to determine nature of the tumour. Management of these lesions is complex, the main problem being the high rates of recurrence in FAP associated disease. Conversely, for intra-abdominal fibromatosis without evidence of FAP, although extensive surgery may still be required for local symptoms, the risk of recurrence appears to be lower. Wide surgical resection with clear margins is the most widely practiced technique with radiation, chemotherapy, or hormonal therapy being used to reduce the risk of recurrence.
Current experimental studies are being done with Gleevec (Imatinib) and Nexavar (sorafenib) for treatment of desmoid tumors, and show promising success rates.
Some benign tumors need no treatment; others may be removed if they cause problems such as seizures, discomfort or cosmetic concerns. Surgery is usually the most effective approach and is used to treat most benign tumors. In some case other treatments may be of use. Adenomas of the rectum may be treated with sclerotherapy, a treatment in which chemicals are used to shrink blood vessels in order to cut off the blood supply. Most benign tumors do not respond to chemotherapy or radiation therapy, although there are exceptions; benign intercranial tumors are sometimes treated with radiation therapy and chemotherapy under certain circumstances. Radiation can also be used to treat hemangiomas in the rectum. Benign skin tumors are usually surgically resected but other treatments such as cryotherapy, curettage, electrodesiccation, laser therapy, dermabrasion, chemical peels and topical medication are used.
Recommendations for individuals from families affected by the syndrome include:
- Avoidance of radiation therapy to reduce risk of secondary radiation induced malignancies,
- Children and adults undergo comprehensive annual physical examination,
- Women undergo age specific breast cancer monitoring beginning at age 25 years, and
- All patients should consult a physician promptly for evaluation of lingering symptoms and illnesses.
The primary method for treatment is surgical, not medical. Radiation and chemotherapy are not needed for benign lesions and are not effective for malignant lesions.
Benign granular cell tumors have a recurrence rate of 2% to 8% when resection margins are deemed clear of tumor infiltration. When the resection margins of a benign granular cell tumor are positive for tumor infiltration the recurrence rate is increased to 20%. Malignant lesions are aggressive and difficult to eradicate with surgery and have a recurrence rate of 32%.
The priority of retinoblastoma treatment is to preserve the life of the child, then to preserve vision, and then to minimize complications or side effects of treatment. The exact course of treatment will depend on the individual case and will be decided by the ophthalmologist in discussion with the paediatric oncologist. Children with involvement of both eyes at diagnosis usually require multimodality therapy (chemotherapy, local therapies)
The various treatment modalities for retinoblastoma includes:
- Enucleation of the eye – Most patients with unilateral disease present with advanced intraocular disease and therefore usually undergo enucleation, which results in a cure rate of 95%. In bilateral Rb, enucleation is usually reserved for eyes that have failed all known effective therapies or without useful vision.
- External beam radiotherapy (EBR) – The most common indication for EBR is for the eye in a young child with bilateral retinoblastoma who has active or recurrent disease after completion of chemotherapy and local therapies. However, patients with hereditary disease who received EBR therapy are reported to have a 35% risk of second cancers.
- Brachytherapy – Brachytherapy involves the placement of a radioactive implant (plaque), usually on the sclera adjacent to the base of a tumor. It used as the primary treatment or, more frequently, in patients with small tumors or in those who had failed initial therapy including previous EBR therapy.
- Thermotherapy – Thermotherapy involves the application of heat directly to the tumor, usually in the form of infrared radiation. It is also used for small tumors
- Laser photocoagulation – Laser photocoagulation is recommended only for small posterior tumors. An argon or diode laser or a xenon arc is used to coagulate all the blood supply to the tumor.
- Cryotherapy – Cryotherapy induces damage to the vascular endothelium with secondary thrombosis and infarction of the tumor tissue by rapidly freezing it. Cryotherapy may be used as primary therapy for small peripheral tumors or for small recurrent tumors previously treated with other methods.
- Systemic chemotherapy – Systemic chemotherapy has become forefront of treatment in the past decade, in the search of globe preserving measures and to avoid the adverse effects of EBR therapy. The common indications for chemotherapy for intraocular retinoblastoma include tumors that are large and that cannot be treated with local therapies alone in children with bilateral tumors. It is also used in patients with unilateral disease when the tumors are small but cannot be controlled with local therapies alone.
- Intra-arterial chemotherapy – Chemotherapeutic drugs are administered locally via a thin catheter threaded through the groin, through the aorta and the neck, directly into the optic vessels.
- Nano-particulate chemotherapy – To reduce the adverse effects of systemic therapy, subconjuctival (local) injection of nanoparticle carriers containing chemotherapeutic agents (carboplatin) has been developed which has shown promising results in the treatment of retinoblastoma in animal models without adverse effects.
- Chemoreduction - A combined approach using chemotherapy to initially reduce the size of the tumor, and adjuvant focal treatments, such as transpupillary thermotherapy, to control the tumor.
Surgical resection of the tumor is the treatment of first choice, either by open laparotomy or laparoscopy. Given the complexity of perioperative management, and the potential for catastrophic intra and postoperative complications, such surgery should be performed only at centers experienced in the management of this disorder. In addition to the surgical expertise that such centers can provide, they will also have the necessary endocrine and anesthesia resources. It may also be necessary to carry out adrenalectomy, a complete surgical removal of the affected adrenal gland(s).
Either surgical option requires prior treatment with the non-specific and irreversible alpha adrenoceptor blocker phenoxybenzamine or a short acting alpha antagonist (e.g. prazosin, terazosin, or doxazosin). Doing so permits the surgery to proceed while minimizing the likelihood of severe intraoperative hypertension (as might occur when the tumor is manipulated). Some authorities would recommend that a combined alpha/beta blocker such as labetalol also be given in order to slow the heart rate. Regardless, a nonselective beta-adrenergic receptor blocker such as propranolol must never be used in the presence of a pheochromocytoma. The mechanism for β-adrenoceptor blocker-associated adverse events is generally ascribed to inhibition of β2-adrenoceptor-mediated vasodilatation, leaving α1-adrenoceptor-mediated vasoconstrictor responses to catecholamines unopposed and, thus, severe and potentially refractory hypertension. However some clinical guidelines permit beta-1 blockade use together with alpha blockers during surgery for control of tachycardia.
The patient with pheochromocytoma is invariably volume depleted. In other words, the chronically elevated adrenergic state characteristic of an untreated pheochromocytoma leads to near-total inhibition of renin-angiotensin activity, resulting in excessive fluid loss in the urine and thus reduced blood volume. Hence, once the pheochromocytoma has been resected, thereby removing the major source of circulating catecholamines, a situation arises where there is both very low sympathetic activity and volume depletion. This can result in profound hypotension. Therefore, it is usually advised to "salt load" pheochromocytoma patients before their surgery. This may consist of simple interventions such as consumption of high salt food pre-operatively, direct salt replacement or through the administration of intravenous saline solution.
Management of MEN2 patients includes thyroidectomy including cervical central and bilateral lymph nodes dissection for MTC, unilateral adrenalectomy for unilateral pheochromocytoma or bilateral adrenalectomy when both glands are involved and selective resection of pathologic parathyroid glands for primary hyperparathyroidism.
Familial genetic screening is recommended to identify at risk subjects who will develop the disease, permitting early management by performing prophylactic thyroidectomy, giving them the best chance of cure.
Prognosis of MEN2 is mainly related to the stage-dependant prognosis of MTC indicating the necessity of a complete thyroid surgery for index cases with MTC and the early thyroidectomy for screened at risk subjects.
Radiation therapy may include photon-beam or proton-beam treatment, or fractionated external beam radiation. Radiosurgery may be used in lieu of surgery in small tumors located away from critical structures. Fractionated external-beam radiation also can be used as primary treatment for tumors that are surgically unresectable or, for patients who are inoperable for medical reasons.
Radiation therapy often is considered for WHO grade I meningiomas after subtotal (incomplete) tumor resections. The clinical decision to irradiate after a subtotal resection is somewhat controversial, as no class I randomized, controlled trials exist on the subject. Numerous retrospective studies, however, have suggested strongly that the addition of postoperative radiation to incomplete resections improves both progression-free survival (i.e. prevents tumor recurrence) and improves overall survival.
In the case of a grade III meningioma, the current standard of care involves postoperative radiation treatment regardless of the degree of surgical resection. This is due to the proportionally higher rate of local recurrence for these higher-grade tumors. Grade II tumors may behave variably and there is no standard of whether to give radiotherapy following a gross total resection. Subtotally resected grade II tumors should be radiated.
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.
Likely, current chemotherapies are not effective. Antiprogestin agents have been used, but with variable results. A 2007 study of whether hydroxyurea has the capacity to shrink unresectable or recurrent meningiomas is being further evaluated.
Treatment of rhabdomyosarcoma is a multidisciplinary practice involving the use of surgery, chemotherapy, radiation, and possibly immunotherapy. Surgery is generally the first step in a combined therapeutic approach. Resectability varies depending on tumor site, and RMS often presents in sites that don't allow for full surgical resection without significant morbidity and loss of function. Less than 20% of RMS tumors are fully resected with negative margins. Fortunately, rhabdomyosarcomas are highly chemosensitive, with approximately 80% of cases responding to chemotherapy. In fact, multi-agent chemotherapy is indicated for all patients with rhabdomyosarcoma. Before the use of adjuvant and neoadjuvant therapy involving chemotherapeutic agents, treatment solely by surgical means had a survival rate of <20%. Modern survival rates with adjuvant therapy are approximately 60–70%.
There are two main methods of chemotherapy treatment for RMS. There is the VAC regimen, consisting of vincristin, actinomyocin D, and cyclophosphamide, and the IVA regimen, consisting of ifosfamide, vincristin, and actinomyocin D. These drugs are administered in 9–15 cycles depending on the staging of the disease and other therapies used. Other drug and therapy combinations may also show additional benefit. Addition of doxorubicin and cisplatin to the VAC regimen was shown to increase survival rates of patients with alveolar-type, early-stage RMS in IRS study III, and this same addition improved survival rates and doubled bladder salvage rates in patients with stage III RMS of the bladder.
Radiation therapy, which kill cancer cells with focused doses of radiation, is often indicated in the treatment of rhabdomyosarcoma, and the exclusion of this treatment from disease management has been shown to increase recurrence rates. Radiation therapy is used when resecting the entirety of the tumor would involve disfigurement or loss of important organs (eye, bladder, etc.). Generally, in any case where a lack of complete resection is suspected, radiation therapy is indicated. Administration is usually following 6–12 weeks of chemotherapy if tumor cells are still present. The exception to this schedule is the presence of parameningeal tumors that have invaded the brain, spinal cord, or skull. In these cases radiation treatment is started immediately. In some cases, special radiation treatment may be required. Brachytherapy, or the placement of small, radioactive “seeds” directly inside the tumor or cancer site, is often indicated in children with tumors of sensitive areas such as the testicles, bladder, or vagina. This reduces scattering and the degree of late toxicity following dosing. Radiation therapy is more often indicated in higher stage classifications.
Immunotherapy is a more recent treatment modality that is still in development. This method involves recruiting and training the patient's immune system to target the cancer cells. This can be accomplished through administering small molecules designed to pull immune cells towards the tumors, taking immune cells pulled from the patient and training to attack tumors through presentation with tumor antigen, or other experimental methods. A specific example here would be presenting some of the patient's dendritic cells, which direct the immune system to foreign cells, with the PAX3-FKHR fusion protein in order to focus the patient's immune system to the malignant RMS cells. All cancers, including rhabdomyosarcoma, could potentially benefit from this new, immune-based approach.
The objective of irradiation is to halt the growth of the acoustic neuroma tumour, it does not excise it from the body, as the term 'radiosurgery' or 'gammaknife' implies. Radiosurgery is only suitable for small to medum size tumors.
Treatment for FAP depends on the genotype. Most individuals with the APC mutation will develop colon cancer by the age of 40, although the less-common attenuated version typically manifests later in life (40–70). Accordingly, in many cases, prophylactic surgery may be recommended before the age of 25, or upon detection if actively monitored. There are several surgical options that involve the removal of either the colon or both the colon and rectum.
- Rectum involved: the rectum and part or all of the colon are removed. The patient may require an ileostomy (permanent stoma where stool goes into a bag on the abdomen) or have an ileo-anal pouch reconstruction. The decision to remove the rectum depends on the number of polyps in the rectum as well as the family history. If the rectum has few polyps, the colon is partly or fully removed and the small bowel (ileum) can be directly connected to the rectum instead (ileorectal anastomosis).
- Rectum not involved: the portion of the colon manifesting polyps can be removed and the ends 'rejoined' (partial colectomy), a surgery that has a substantial healing time, but leaves quality of life largely intact.
Prophylactic colectomy is indicated if more than a hundred polyps are present, if there are severely dysplastic polyps, or if multiple polyps larger than 1 cm are present.
Treatment for the two milder forms of FAP may be substantially different from the more usual variant, as the number of polyps are far fewer, allowing more options.
Various medications are being investigated for slowing malignant degeneration of polyps, most prominently the non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDS have been shown to significantly decrease the number of polyps but do not usually alter management since there are still too many polyps to be followed and treated endoscopically.
A recommend surveillance program for Multiple Endocrine Neoplasia Type 1 has been suggested by the International Guidelines for Diagnosis and Therapy of MEN syndromes group.
In localized, resectable adult GISTs, if anatomically and physiologically feasible, surgery is the primary treatment of choice. Surgery can be potentially curative, but watchful waiting may be considered in small tumors in carefully selected situations. Post-surgical adjuvant treatment may be recommended. Lymph node metastases are rare, and routine removal of lymph nodes is typically not necessary. Laparoscopic surgery, a minimally invasive abdominal surgery using telescopes and specialized instruments, has been shown to be effective for removal of these tumors without needing large incisions. The clinical issues of exact surgical indications for tumor size are controversial. The decision of appropriate laparoscopic surgery is affected by tumor size, location, and growth pattern.
Radiotherapy has not historically been effective for GISTs and GISTs do not respond to most chemotherapy medications, with responses in less than 5%. However, three medications have been identified for clinical benefit in GIST: imatinib, sunitinib, and regorafenib.
Imatinib (Glivec/Gleevec), an orally administered drug initially marketed for chronic myelogenous leukemia based on bcr-abl inhibition, also inhibits both "c-kit" tyrosine kinase mutations and PDGFRA mutations other than D842V, is useful in treating GISTs in several situations. Imatinib has been used in selected neoadjuvant settings. In the adjuvant treatment setting, the majority of GIST tumors are cured by surgery, and do not need adjuvant therapy. However, a substantial proportion of GIST tumors have a high risk of recurrence as estimated by a number of validated risk stratification schemes, and can be considered for adjuvant therapy. The selection criteria underpinning the decision for possible use of imatinib in these settings include a risk assessment based on pathological factors such as tumor size, mitotic rate, and location can be used to predict the risk of recurrence in GIST patients. Tumors <2 cm with a mitotic rate of <5/50 HPF have been shown to have lower risk of recurrence than larger or more aggressive tumors. Following surgical resection of GISTs, adjuvant treatment with imatinib reduces the risk of disease recurrence in higher risk groups. In selected higher risk adjuvant situations, imatinib is recommended for 3 years.
Imatinib was approved for metastatic and unresectable GIST by the US FDA, February 1, 2002. The two-year survival of patients with advanced disease has risen to 75–80% following imatinib treatment.
If resistance to imatinib is encountered, the multiple tyrosine kinase inhibitor sunitinib (marketed as Sutent) can be considered.
The effectiveness of imatinib and sunitinib depend on the genotype. cKIT- and PDGFRA-mutation negative GIST tumors are usually resistant to treatment with imatinib as is neurofibromatosis-1-associated wild-type GIST. A specific subtype of PDGFRA-mutation, D842V, is also insensitive to imatinib.
Regorafenib (Stivarga) was FDA approved in 2013 for advanced GISTs that cannot be surgically removed and that no longer respond to imatinib (Gleevec) and sunitinib (Sutent).
Acoustic neuromas are managed by either surgery, radiation therapy, or observation with regular MRI scanning. With treatment, the likelihood of hearing preservation varies inversely with the size of the tumor; for large tumors, preservation of hearing is rare. Because acoustic neurmas, meningiomas and most other CPA tumors are benign, slow growing or non-growing, and non-invasive, observation is a viable management option.
Chemotherapy regimens for pediatric ependymomas have produced only modest benefit and degree of resection remains the most conspicuous factor in recurrence and survival.
The association of "TERT" expression with poor outcome in pediatric ependymomas has driven some researchers to suggest that telomerase inhibition may be an effective adjuvant therapy for pediatric ependymomas. Further, data from "in vitro" experiments using primary tumor isolate cells suggest that inhibition of telomerase activity may inhibit cell proliferation and increase sensitivity of cells to DNA damaging agents, consistent with the observation of high telomerase activity in primary tumors. Additionally, because apurinic/apyrimidinic endonuclease ("APE1") has been found to confer radiation resistance in pediatric ependymomas, it has been suggested that inhibitors of Ap endo activity might also restore radiation sensitivity.
Within the infratentorial group of pediatric ependymomas, radiotherapy was found to significantly increase 5-year survival. However, a retrospective review of sterotactic radiosurgery showed it provided only a modest benefit to patients who had previously undergone resection and radiation. Though other supratentorial tumors tend to have a better prognosis, supratentorial anaplastic ependymomas are the most aggressive ependymoma and neither total excision nor postoperative irradiation was found to be effective in preventing early recurrence.
Following resection of infratentorial ependymomas, residual tumor is more likely in lateral versus medial tumors, classified radiologically pre-operatively. Specific techniques, such as cerebellomedullary fissure dissection have been proposed to aid in complete resection while avoiding iatrogenic effects in these cases. Surveillance neuroimaging for recurrence provides additional survival to patients over observation alone.
Prior to reaching the advanced stages of colorectal cancer, the polyps are confined to the inner wall and thickness of the intestinal tract and do not metastasize or 'spread'. So provided FAP is detected and controlled either at the pre-cancerous stage or when any cancerous polyps are still internal to the intestinal tract, surgery has a very high success rate of preventing or removing cancer, without recurrence, since the locations giving rise to cancer are physically removed "in toto" by the surgery.
Following surgery, if a partial colectomy has been performed, colonoscopic surveillance of the remaining colon is necessary as the individual still has a risk of developing colon cancer. However, if this happened, it would be a fresh incident from polyps developing anew in the unremoved part of the colon subsequent to surgery, rather than a return or metastasis of any cancer removed by the original surgery.
Even if the tumor has advanced and metastasized, making curative surgery infeasible, surgery often has a role in neuroendocrine cancers for palliation of symptoms and possibly increased lifespan.
Cholecystectomy is recommended if there is a consideration of long-term treatment with somatostatin analogs.