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Surgical excision is the preferred method of treatment for benign glomus tumors.
Craniopharyngiomas are usually successfully managed with a combination of adjuvant chemotherapy and neurosurgery. Recent research describes the rare occurrence of malignant transformations of these normally benign tumors. Malignant craniopharyngiomas can occur at any age, are slightly more common in females, and are usually of the adamantinomatous type.
The malignant transformations can take years to occur (although 1 in 5 of the diagnosed cases were de novo transformations), hence the need for lengthier follow up in patients diagnosed with the more common benign forms.
There was no link found between malignancy and initial chemo-radiotherapy treatment, and the overall survival rate was very poor with median survival being 6 months post diagnosis of malignancy.
Urine catecholamine level can be elevated in pre-clinical neuroblastoma. Screening asymptomatic infants at three weeks, six months, and one year has been performed in Japan, Canada, Austria and Germany since the 1980s. Japan began screening six-month-olds for neuroblastoma via analysis of the levels of homovanillic acid and vanilmandelic acid in 1984. Screening was halted in 2004 after studies in Canada and Germany showed no reduction in deaths due to neuroblastoma, but rather caused an increase in diagnoses that would have disappeared without treatment, subjecting those infants to unnecessary surgery and chemotherapy.
There are a few scans and tests that the physician can conduct in order to diagnose a person with craniopharyngioma. Your doctor may order a high-resolution magnetic resonance imaging (MRI) scan. This test is valuable because it allows the neuroradiologist to view the tumor from different angles.
In some cases, a powerful 3T (Tesla) MRI scanner can help define the location of critical brain structures affected by the tumor.The histologic pattern consists of nesting of squamous epithelium bordered by radially arranged cells. It is frequently accompanied by calcium deposition and may have a microscopic papillary architecture.A computed tomography (CT) scan is also a good diagnostic tool as it detects calcification in the tumor.
Two distinct types are recognized:
- Adamantinomatous craniopharyngiomas, which resemble ameloblastomas (the most common type of odontogenic tumor), are characterized by activating CTNNB1 mutations; and,
- Papillary craniopharyngiomas are characterized by BRAFv600E mutations.
In the adamantinomatous type, calcifications are visible on neuroimaging and are helpful in diagnosis.
The papillary type rarely calcifies. A vast majority of craniopharyngiomas in children are adamantiomatous whereas both subtypes are common in adults. Mixed type tumors also occur.
On macroscopic examination, craniopharyngiomas are cystic or partially cystic with solid areas. On light microscopy, the cysts are seen to be lined by stratified squamous epithelium. Keratin pearls may also be seen. The cysts are usually filled with a yellow, viscous fluid which is rich in cholesterol crystals. Of a long list of possible symptoms, the most common presentations include: headaches, growth failure, and bitemporal hemianopsia.
The standard work-up for AT/RT includes:
- Magnetic resonance imaging (MRI) of the brain and spine
- Lumbar puncture to look for M1 disease
- Computed tomography (CT) of chest and abdomen to check for a tumor
- Bone marrow aspiration to check for bone tumors. Sometimes the physician will perform a stem cell transplant
- Bone marrow biopsy
- Bone scan
The initial diagnosis of a tumor is made with a radiographic study (MRI or CT-). If CT was performed first, an MRI is usually performed as the images are often more detailed and may reveal previously undetected metastatic tumors in other locations of the brain. In addition, an MRI of the spine is usually performed. The AT/RT tumor often spreads to the spine. AT/RT is difficult to diagnose only from radiographic study; usually, a pathologist must perform a cytological or genetic analysis.
Examination of the cerebrospinal fluid is important (CSF), as one-third of patients will have intracranial dissemination with involvement of the CSF. Large tumor cells, eccentricity of the nuclei, and prominent nucleoli are consistent findings. Usually only a minority of AT/RT biopsies have rhabdoid cells, making diagnosis more difficult. Increasingly it is recommended that a genetic analysis be performed on the brain tumor, especially to find if a deletion in the INI1/hSNF5 gene is involved (appears to account for over 80% of the cases). The correct diagnosis of the tumor is critical to any protocol. Studies have shown that 8% to over 50% of AT/RT tumors are diagnosed incorrectly.
Medical imaging plays a central role in the diagnosis of brain tumors. Early imaging methods – invasive and sometimes dangerous – such as pneumoencephalography and cerebral angiography have been abandoned in favor of non-invasive, high-resolution techniques, especially magnetic resonance imaging (MRI) and computed tomography (CT) scans. Neoplasms will often show as differently colored masses (also referred to as processes) in CT or MRI results.
- Benign brain tumors often show up as hypodense (darker than brain tissue) mass lesions on CT scans. On MRI, they appear either hypodense or isointense (same intensity as brain tissue) on T1-weighted scans, or hyperintense (brighter than brain tissue) on T2-weighted MRI, although the appearance is variable.
- Contrast agent uptake, sometimes in characteristic patterns, can be demonstrated on either CT or MRI scans in most malignant primary and metastatic brain tumors.
- Pressure areas where the brain tissue has been compressed by a tumor also appear hyperintense on T2-weighted scans and might indicate the presence a diffuse neoplasm due to an unclear outline. Swelling around the tumor known as "peritumoral edema" can also show a similar result.
This is because these tumors disrupt the normal functioning of the BBB and lead to an increase in its permeability. However, it is not possible to diagnose high- versus low-grade gliomas based on enhancement pattern alone.
The definitive diagnosis of brain tumor can only be confirmed by histological examination of tumor tissue samples obtained either by means of brain biopsy or open surgery. The histological examination is essential for determining the appropriate treatment and the correct prognosis. This examination, performed by a pathologist, typically has three stages: interoperative examination of fresh tissue, preliminary microscopic examination of prepared tissues, and follow-up examination of prepared tissues after immunohistochemical staining or genetic analysis.
The diagnosis of a mediastinal germ cell tumor should be considered in all young males with a mediastinal mass. In addition to physical examination and routine laboratory studies, initial evaluation should include CT of the chest and abdomen, and determination of serum levels of HCG and alpha-fetoprotein.
10-year survival rates for mucinous tumors is excellent in the absence of invasion.
In the case of borderline tumors confined to the ovary and malignant tumors without invasion, the survival rates are 90% or greater. In invasive mucinous cystadenocarcinomas, the survival is approximately 30%
For surface epithelial-stromal tumors, the most common sites of metastasis are the pleural cavity (33%), the liver (26%), and the lungs (3%).
Another way to detect neuroblastoma is the mIBG scan (meta-iodobenzylguanidine), which is taken up by 90 to 95% of all neuroblastomas, often termed "mIBG-avid." The mechanism is that mIBG is taken up by sympathetic neurons, and is a functioning analog of the neurotransmitter norepinephrine. When it is radio-ionated with I-131 or I-123 (radioactive iodine isotopes), it is a very good radiopharmaceutical for diagnosis and monitoring of response to treatment for this disease. With a half-life of 13 hours, I-123 is the preferred isotope for imaging sensitivity and quality. I-131 has a half-life of 8 days and at higher doses is an effective therapy as targeted radiation against relapsed and refractory neuroblastoma.
Although often described as benign, a teratoma does have malignant potential. In a UK study of 351 infants and children diagnosed with "benign" teratoma reported 227 with MT, 124 with IT. Five years after surgery, event-free survival was 92.2% and 85.9%, respectively, and overall survival was 99% and 95.1%. A similar study in Italy reported on 183 infants and children diagnosed with teratoma. At 10 years after surgery, event free and overall survival were 90.4% and 98%, respectively.
Depending on which tissue(s) it contains, a teratoma may secrete a variety of chemicals with systemic effects. Some teratomas secrete the "pregnancy hormone" human chorionic gonadotropin (βhCG), which can be used in clinical practice to monitor the successful treatment or relapse in patients with a known HCG-secreting teratoma. This hormone is not recommended as a diagnostic marker, because most teratomas do not secrete it. Some teratomas secrete thyroxine, in some cases to such a degree that it can lead to clinical hyperthyroidism in the patient. Of special concern is the secretion of alpha-fetoprotein (AFP); under some circumstances AFP can be used as a diagnostic marker specific for the presence of yolk sac cells within the teratoma. These cells can develop into a frankly malignant tumor known as yolk sac tumor or endodermal sinus tumor.
Adequate follow-up requires close observation, involving repeated physical examination, scanning (ultrasound, MRI, or CT), and measurement of AFP and/or βhCG.
DNA testing is now the preferred method of establishing a diagnosis for MEN 2B, and is thought to be almost 100% sensitive and specific. Gordon et al. reported cases of a difference disease—the "multiple mucosal neuroma syndrome"—having the physical phenotype of MEN2B, but without variations in the RET gene and without malignancy.
MEN2B should be entertained as a diagnosis whenever a person is found to have either medullary thyroid carcinoma or pheochromocytoma. Before DNA testing became available, measurement of serum calcitonin was the most important laboratory test for MEN2B. Calcitonin is produced by the "C" cells of the thyroid, which, because they are always hyperplastic or malignant in MEN2B, produce more calcitonin than normal. Calcitonin levels remain a valuable marker to detect recurrence of medullary thyroid carcinoma after thyroidectomy.
Luxol fast blue staining identifies myelin sheathing of some fibers, and lesional cells react immunohistochemically for S-100 protein, collagen type IV, vimentin, NSE, and neural filaments. More mature lesions will react also for EMA, indicating a certain amount of perineurial differentiation. Early lesions, rich in acid mucopolysaccharides, stain positively with alcian blue. When medullary thyroid cancer is present, levels of the hormone calcitonin are elevated in serum and urine. Under the microscope, tumors may closely resemble traumatic neuroma, but the streaming fascicles of mucosal neuroma are usually more uniform and the intertwining nerves of the traumatic neuroma lack the thick perineurium of the mucosal neuroma. Inflammatory cells are not seen in the stroma and dysplasia is not present in the neural tissues.
Appearance and location of the tumor is enough to identify it as a mammary tumor. Biopsy will give type and invasiveness of the tumor. In addition, newer studies showed that certain gene expression patterns are associated with malignant behaviour of canine mammary tumors.
Surgical removal is the treatment of choice, but chest x-rays should be taken first to rule out metastasis. Removal should be with wide margins to prevent recurrence, taking the whole mammary gland if necessary. Because 40 to 50 percent of dog mammary tumors have estrogen receptors, spaying is recommended by many veterinarians. A recent study showed a better prognosis in dogs that are spayed at the time of surgery or that had been recently spayed. However, several other studies found no improvement of disease outcome when spaying was performed after the tumor had developed. Chemotherapy is rarely used.
Cytogenetics is the study of a tumor’s genetic make-up. Fluorescent "in situ" hybridization may be able to help locate a mutation or abnormality that may be allowing tumor growth. This technique has been shown to be useful in identifying some tumors and distinguishing two histologically similar tumors from each other (such as AT/RTs and PNETs). In particular, medulloblastmas/PNETs may possibly be differentiated cytogenetically from AT/RTs, as chromosomal deletions of 17p are relatively common with medulloblastoma and abnormalities of 22q11.2 are not seen. However, chromosomal 22 deletions are very comomon in AT/RTs.
In importance of the "hSNF5/INI1" gene located on chromosomal band 22q11.2 is highlighted, as the mutation’s presence is sufficient to change the diagnosis from a medulloblastoma or PNET to the more aggressive AT/RT classification. However, this mutation is not present in 100% of cases. Therefore, if the mutation is not present in an otherwise classic AT/RT immunohistochemical and morphologic pattern then the diagnosis remains an AT/RT.
Because of the rarity of these tumors, there is still a lot of unknown information. There are many case studies that have been reported on patients who have been diagnosed with this specific type of tumor. Most of the above information comes from the findings resulting from case studies.
Since Papillary Tumors of the Pineal Region were first described in 2003, there have been seventy cases published in the English literature. Since there is such a small number of cases that have been reported, the treatment guidelines have not been established. A larger number of cases that contain a longer clinical follow-up are needed to optimize the management of patients with this rare disease.
Even though there is a general consensus on the morphology and the immunohistochemical characteristics that is required for the diagnosis, the histological grading criteria have yet to be fully defined and its biological behavior appears to be variable. This specific type of tumor appears to have a high potential for local recurrence with a high tumor bed recurrence rate during the five years after the initial surgery. This suggests the need for a tumor bed boost radiotherapy after surgical resection.
As stated above, the specific treatment guidelines have not yet been established, however, gross total resection of the tumor has been the only clinical factor associated overall and progression-free survival. The value of radiotherapy as well as chemotherapy on disease progression will need to be investigated in future trials. With this information, it will provide important insight into long-term management and may further our understanding of the histologic features of this tumor.
Genetic counseling and genetic testing are used to confirm that somebody has this gene mutation. Once such a person is identified, early and regular screenings for cancer are recommended for him or her as people with Li–Fraumeni are likely to develop another primary malignancy at a future time (57% within 30 years of diagnosis).
A 2009 revision of the traditional Chompret criteria for screening has been proposed:
A proband who has:
- tumor belonging to the LFS tumor spectrum - soft tissue sarcoma, osteosarcoma, pre-menopausal breast cancer, brain tumor, adrenocortical carcinoma, leukemia or lung bronchoalveolar cancer - before age 46 years;
and at least one of the following:
- at least one first or second degree relative with an LFS tumour (except breast cancer if the proband has breast cancer) before age 56 years or with multiple tumours
- a proband with multiple tumours (except multiple breast tumours), two of which belong to the LFS tumour spectrum and the first of which occurred before age 46 years
- a proband who is diagnosed with adrenocortical carcinoma or choroid plexus tumour, irrespective of family history
Identifying the "RB1" gene mutation that led to a child's retinoblastoma can be important in the clinical care of the affected individual and in the care of (future) siblings and offspring.It may run in the family.
1. Bilaterally affected individuals and 13-15% of unilaterally affected individuals, are expected to show an RB1 mutation in blood. By identifying the "RB1" mutation in the affected individual, (future) siblings, children, and other relatives can be tested for the mutation; if they do not carry the mutation, child relatives are not at risk of retinoblastoma so need not undergo the trauma and expense of examinations under anaesthetic. For the 85% of unilaterally affected patients found not to carry either of their eye tumor RB1 mutations in blood, neither molecular testing nor clinical surveillance of siblings is required.
2. If the "RB1" mutation of an affected individual is identified, amniotic cells in an at-risk pregnancy can be tested for the family mutation; any fetus that carries the mutation can be delivered early, allowing early treatment of any eye tumors, leading to better visual outcomes.
3. For cases of unilateral retinoblastoma where no eye tumor is available for testing, if no "RB1" mutation is detected in blood after high sensitivity molecular testing (i.e. >93% RB1 mutation detection sensitivity), the risk of a germline "RB1" mutation is reduced to less than 1%, a level at which only clinic examination (and not examinations under anaesthetic) is recommended for the affected individual and their future offspring (National Retinoblastoma Strategy, Canadian Guidelines for Care).
Anaplastic astrocytoma, Astrocytoma, Central neurocytoma, Choroid plexus carcinoma, Choroid plexus papilloma, Choroid plexus tumor, Dysembryoplastic neuroepithelial tumour, Ependymal tumor, Fibrillary astrocytoma, Giant-cell glioblastoma, Glioblastoma multiforme, Gliomatosis cerebri, Gliosarcoma, Hemangiopericytoma, Medulloblastoma, Medulloepithelioma, Meningeal carcinomatosis, Neuroblastoma, Neurocytoma, Oligoastrocytoma, Oligodendroglioma, Optic nerve sheath meningioma, Pediatric ependymoma, Pilocytic astrocytoma, Pinealoblastoma, Pineocytoma, Pleomorphic anaplastic neuroblastoma, Pleomorphic xanthoastrocytoma, Primary central nervous system lymphoma, Sphenoid wing meningioma, Subependymal giant cell astrocytoma, Subependymoma, Trilateral retinoblastoma.
If the eye examination is abnormal, further testing may include imaging studies, such as computerized tomography (CT), magnetic resonance imaging (MRI), and ultrasound. CT and MRI can help define the structure abnormalities and reveal any calcium depositions. Ultrasound can help define the height and thickness of the tumor. Bone marrow examination or lumbar puncture may also be done to determine any metastases to bones or the brain.
Following diagnosis and histopathological analysis, the patient will usually undergo magnetic resonance imaging (MRI), ultrasonography, and a bone scan in order to determine the extent of local invasion and metastasis. Further investigational techniques may be necessary depending on tumor sites. A parameningeal presentation of RMS will often require a lumbar puncture to rule out metastasis to the meninges. A paratesticular presentation will often require an abdominal CT to rule out local lymph node involvement, and so on. Patient outcomes are most strongly tied to the extent of the disease, so it is important to map its presence in the body as soon as possible in order to decide on a treatment plan.
The current staging system for rhabdomyosarcoma is unusual relative to most cancers. It utilizes a modified TNM (tumor-nodes-metastasis) system originally developed by the IRSG. This system accounts for tumor size (> or <5 cm), lymph node involvement, tumor site, and presence of metastasis. It grades on a scale of 1 to 4 based on these criteria. In addition, patients are sorted by clinical group (from the clinical groups from the IRSG studies) based on the success of their first surgical resection. The current Children's Oncology Group protocols for the treatment of RMS categorize patients into one of four risk categories based on tumor grade and clinical group, and these risk categories have been shown to be highly predictive of outcome.
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.
DSRCT is frequently misdiagnosed. Adult patients should always be referred to a sarcoma specialist. This is an aggressive, rare, fast spreading tumor and both pediatric and adult patients should be treated at a sarcoma center.
There is no standard protocol for the disease; however, recent journals and studies have reported that some patients respond to high-dose (P6 Protocol) chemotherapy, maintenance chemotherapy, debulking operation, cytoreductive surgery, and radiation therapy. Other treatment options include: hematopoietic stem cell transplantation, intensity-modulated radiation Therapy, radiofrequency ablation, stereotactic body radiation therapy, intraperitoneal hyperthermic chemoperfusion, and clinical trials.
Medulloblastomas affect just under two people per million per year, and affect children 10 times more than adults. Medulloblastoma is the second-most frequent brain tumor in children after pilocytic astrocytoma and the most common malignant brain tumor in children, comprising 14.5% of newly diagnosed cases. In adults, medulloblastoma is rare, comprising fewer than 2% of CNS malignancies.
The rate of new cases of childhood medulloblastoma is higher in males (62%) than females (38%), a feature which is not seen in adults. Medulloblastoma and other PNET`s are more prevalent in younger children than older children. About 40% of medulloblastoma patients are diagnosed before the age of five, 31% are between the ages of 5 and 9, 18.3% are between the ages of 10 and 14, and 12.7% are between the ages of 15 and 19.
Rhabdomyosarcoma is often difficult to diagnose due to its similarities to other cancers and varying levels of differentiation. It is loosely classified as one of the “small, round, blue-cell cancer of childhood” due to its appearance on an H&E stain. Other cancers that share this classification include neuroblastoma, Ewing sarcoma, and lymphoma, and a diagnosis of RMS requires confident elimination of these morphologically similar diseases. The defining diagnostic trait for RMS is confirmation of malignant skeletal muscle differentiation with myogenesis (presenting as a plump, pink cytoplasm) under light microscopy. Cross striations may or may not be present. Accurate diagnosis is usually accomplished through immunohistochemical staining for muscle-specific proteins such as myogenin, muscle-specific actin, desmin, D-myosin, and myoD1. Myogenin, in particular, has been shown to be highly specific to RMS, although the diagnostic significance of each protein marker may vary depending on the type and location of the malignant cells. The alveolar type of RMS tends to have stronger muscle-specific protein staining. Electron microscopy may also aid in diagnosis, with the presence of actin and myosin or Z bands pointing to a positive diagnosis of RMS. Classification into types and subtypes is accomplished through further analysis of cellular morphology (alveolar spacings, presence of cambium layer, aneuploidy, etc.) as well as genetic sequencing of tumor cells. Some genetic markers, such as the "PAX3-FKHR" fusion gene expression in alveolar RMS, can aid in diagnosis. Open biopsy is usually required to obtain sufficient tissue for accurate diagnosis. All findings must be considered in context, as no one trait is a definitive indicator for RMS.