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In reported cases of the tumor over the last 25 years, the number of affected females with astroblastoma is significantly higher than the number of affected males. Sughrue et al. confirmed this trend, stating that 70% of the cases with clearly stated gender were female (100 cases total). While several publications support a genetic predisposition to females, the underlying reasons are still unknown.
Use of telomerase inhibitors such as Imetelstat seem to have very low toxicity compared to other chemotherapy. The only known side effect of most telomerase inhibitors is dose-induced neutropenia. Neuropsychological deficits can result from resection, chemotherapy, and radiation, as well as endocrinopathies. Additionally, an increase in gastrointestinal complications has been observed in survivors of pediatric cancers.
At this point, no literature has indicated whether environmental factors increase the likelihood of astroblastoma. Although cancer in general is caused by a variety of external factors, including carcinogens, dangerous chemicals, and viral infections, astroblastoma research has not even attempted to classify incidence in this regard. The next few decades will aid in this understanding.
The 5-year disease-free survival for age >5 years is 50-60%. Another report found a similar 5-year survival at about 65% with 51% progression-free survival. The 10-year disease-free survival is 40-50%. Younger ages showed lower 5 and 10-year survival rates. A 2006 study that observed 133 patients found 31 (23.3%) had a recurrence of the disease within a five-year period.
The majority of patients can be expected to be cured of their disease and become long-term survivors of central neurocytoma. As with any other type of tumor, there is a chance for recurrence. The chance of recurrence is approximately 20%. Some factors that predict tumor recurrence and death due to progressive states of disease are high proliferative indices, early disease recurrence, and disseminated disease with or without the spread of disease through the cerebral spinal fluid. Long-term follow up examinations are essential for the evaluation of the outcomes that each treatment brings about. It is also essential to identify possible recurrence of CN. It is recommended that a cranial MRI is performed between every 6–12 months.
Neuroblastoma comprises 6–10% of all childhood cancers, and 15% of cancer deaths in children. The annual mortality rate is 10 per million children in the 0- to 4-year-old age group, and 4 per million in the 4- to 9-year old age group.
The highest incidence is in the first year of life, and some cases are congenital. The age range is broad, including older children and adults, but only 10% of cases occur in people older than 5 years of age. A large European study reported less than 2% of over 4000 neuroblastoma cases were over 18 years old.
Papillary tumors of pineal region are extremely rare, constituting 0.4-1% of all central nervous system tumors. These tumors most commonly occur in adults with the mean age being 31.5. There have been cases reported for people between the ages 5 to 66 years. There is a slight predominance of females who have these tumors.
Based on a series of 493 neuroblastoma samples, it has been reported that overall genomic pattern, as tested by array-based karyotyping, is a predictor of outcome in neuroblastoma:
- Tumors presenting exclusively with whole chromosome copy number changes were associated with excellent survival.
- Tumors presenting with any kind of segmental chromosome copy number changes were associated with a high risk of relapse.
- Within tumors showing segmental alterations, additional independent predictors of decreased overall survival were N-myc amplification, 1p and 11q deletions, and 1q gain.
Earlier publications categorized neuroblastomas into three major subtypes based on cytogenetic profiles:
- Subtype 1: favorable neuroblastoma with near triploidy and a predominance of numerical gains and losses, mostly representing non-metastatic NB stages 1, 2 and 4S.
- Subtypes 2A and 2B: found in unfavorable widespread neuroblastoma, stages 3 and 4, with 11q loss and 17q gain without N-myc amplification (subtype 2A) or with N-myc amplification often together with 1p deletions and 17q gain (subtype 2B).
Virtual karyotyping can be performed on fresh or paraffin-embedded tumors to assess copy number at these loci. SNP array virtual karyotyping is preferred for tumor samples, including neuroblastomas, because they can detect copy neutral loss of heterozygosity (acquired uniparental disomy). Copy neutral LOH can be biologically equivalent to a deletion and has been detected at key loci in neuroblastoma. ArrayCGH, FISH, or conventional cytogenetics cannot detect copy neutral LOH.
Ependymomas make up about 5% of adult intracranial gliomas and up to 10% of childhood tumors of the central nervous system (CNS). Their occurrence seems to peak at age 5 years and then again at age 35. They develop from cells that line both the hollow cavities of the brain and the canal containing the spinal cord, but they usually arise from the floor of the fourth ventricle, situated in the lower back portion of the brain, where they may produce headache, nausea and vomiting by obstructing the flow of cerebrospinal fluid. This obstruction may also cause hydrocephalus. They may also arise in the spinal cord, conus medullaris and supratentorial locations. Other symptoms can include (but are not limited to): loss of appetite, difficulty sleeping, temporary inability to distinguish colors, uncontrollable twitching, seeing vertical or horizontal lines when in bright light, and temporary memory loss. It should be remembered that these symptoms also are prevalent in many other illnesses not associated with ependymoma.
About 10% of ependymomas are benign myxopapillary ependymoma (MPE). MPE is a localized and slow-growing low-grade tumor, which originates almost exclusively from the lumbosacral nervous tissue of young patients. On the other hand, it is the most common tumor of the lumbosacral canal comprising about 90% of all tumoral lesions in this region.
Although some ependymomas are of a more anaplastic and malignant type, most of them are not anaplastic. Well-differentiated ependymomas are usually treated with surgery. For other ependymomas, total surgical removal is the preferred treatment in addition to radiation therapy. The malignant (anaplastic) varieties of this tumor, malignant ependymoma and the ependymoblastoma, are treated similarly to medulloblastoma but the prognosis is much less favorable. Malignant ependymomas may be treated with a combination of radiation therapy and chemotherapy. Ependymoblastomas, which occur in infants and children younger than 5 years of age, may spread through the cerebrospinal fluid and usually require radiation therapy. The subependymoma, a variant of the ependymoma, is apt to arise in the fourth ventricle but may occur in the septum pellucidum and the cervical spinal cord. It usually affects people over 40 years of age and more often affects men than women.
Extraspinal ependymoma (EEP), also known as extradural ependymoma, may be an unusual form of teratoma or may be confused with a sacrococcygeal teratoma.
Definitive treatment for ganglioglioma requires gross total surgical resection, and a good prognosis is generally expected when this is achieved. However, indistinct tumor margins and the desire to preserve normal spinal cord tissue, motor and sensory function may preclude complete resection of tumor. According to a series by Lang et al., reviewing several patients with resected spinal cord ganglioglioma, the 5- and 10-year survival rates after total resection were 89% and 83%, respectively. In that study, patients with spinal cord ganglioglioma had a 3.5-fold higher relative risk of tumor recurrence compared to patients with supratentorial ganglioglioma. It has been recognized that postoperative results correlate closely with preoperative neurological status as well as the ability to achieve complete resection.
With the exception of WHO grade III anaplastic ganglioglioma, radiation therapy is generally regarded to have no role in the treatment of ganglioglioma. In fact, radiation therapy may induce malignant transformation of a recurrent ganglioglioma several years later. Adjuvant chemotherapy is also typically reserved for anaplastic ganglioglioma, but has been used anecdotally in partially resected low grade spinal cord gangliogliomas which show evidence of disease progression.
Central neurocytoma, abbreviated CNC, is an extremely rare, ordinarily benign intraventricular brain tumour that typically forms from the neuronal cells of the septum pellucidum. The majority of central neurocytomas grow inwards into the ventricular system forming interventricular neurocytomas. This leads to two primary symptoms of CNCs, blurred vision and increased intracranial pressure. Treatment for a central neurocytoma typically involves surgical removal, with an approximate 1 in 5 chance of recurrence. Central neurocytomas are classified as a grade II tumor under the World Health Organization's classification of tumors of the nervous system.
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.
Ependymoma is a tumor that arises from the ependyma, a tissue of the central nervous system. Usually, in pediatric cases the location is intracranial, while in adults it is spinal. The common location of intracranial ependymoma is the fourth ventricle. Rarely, ependymoma can occur in the pelvic cavity.
Syringomyelia can be caused by an ependymoma.
Ependymomas are also seen with neurofibromatosis type II.
The cause of oligodendrogliomas is unknown. Some studies have linked oligodendroglioma with a viral cause. A 2009 Oxford Neurosymposium study illustrated a 69% correlation between NJDS gene mutation and the tumor initiation shown by Kevin Smith. A single case report has linked oligodendroglioma to irradiation of pituitary adenoma.
Gangliogliomas are generally benign WHO grade I tumors; the presence of anaplastic changes in the glial component is considered to represent WHO grade III (anaplastic ganglioglioma). Criteria for WHO grade II have been suggested, but are not established. Malignant transformation of spinal ganglioglioma has been seen in only a select few cases. Poor prognostic factors for adults with gangliogliomas include older age at diagnosis, male sex, and malignant histologic features.
Oligodendrogliomas are generally felt to be incurable using current treatments. However compared to the more common astrocytomas, they are slowly growing with prolonged survival. In one series, median survival times for oligodendrogliomas were 11.6 years for grade II and 3.5 years for grade III.
However, such figures can be misleading since they do not factor in the types of treatment nor the genetic signature of the tumors. A recent study analyzed survival based on chromosomal deletions and the effects of radiation or chemotherapy as treatment, with the following results (both low-grade and anaplastic oligodendrogliomas): 1p/19q deletion with radiation = 121 months (mean), 1p/19q deletion with chemotherapy = over 160 months (mean not yet reached), no 1p/19q deletion with radiation = 58 months (mean), and no 1p/19q deletion with chemotherapy = 75 months (mean). Another study divided anaplastic oligodendrogliomas into the following four clinically relevant groups of histology with the following results: combined 1p/19q loss = median survival was >123 months (not yet reached), 1p loss only = median survival was 71 months, 1p intact with TP53 mutation = median survival 71 months, and 1p intact with no TP53 mutation = median survival was 16 months.
Because of the indolent nature of these tumors and the potential morbidity associated with neurosurgery, chemotherapy and radiation therapy, most neurooncologists will initially pursue a course of watchful waiting and treat patients symptomatically. Symptomatic treatment often includes the use of anticonvulsants for seizures and steroids for brain swelling. PCV chemotherapy (Procarbazine, CCNU and Vincristine) has been shown to be effective and was the most commonly used chemotherapy regimen used for treating anaplastic oligodendrogliomas, but is now being superseded by a newer drug: Temozolomide. Temozolomide is a common chemotherapeutic drug to which oligodendrogliomas appear to be quite sensitive. It is often used as a first line therapy, especially because of its relatively mild side effects when compared to other chemotherapeutic drugs.
Nevertheless, a retrospective study on 1054 patients with anaplastic oligodendroglioma, presented during the 2009 ASCO Annual Meeting, suggests that PCV therapy may be superior in efficacy to the newer temozolomide therapy. Median time to progression for patients with 1p19q co-deletion was longer following PCV alone (7.6 years) than with temozolomide alone (3.3 years); median overall survival was also longer with PCV treatment versus temozolomide treatment (not reached, vs. 7.1 years).
The standard dosing schedule of temozolomide is 5 consecutive days of daily dosing during 28-day cycles. However, different dosing schedules may produce better results, such as continuous daily dosing using lower amounts of drug (e.g. 21-day dosing during 28-day cycles). As an example of an altered dosing schedule, promising results have been shown using lower daily doses on each day for 7 weeks, followed by a 4-week off periods. Regarding the duration of dosing, for oligodendrogliomas the duration prescribed by oncologists varies considerably and seems to range from 6 cycles to over 32 cycles (i.e. over 3 years). In one study, researchers compared patients who received temozolomide for at least 12 months on the 5/28 day cycle, dividing such patients into two groups: "short term" patients receiving temozolomide for 12-18 cycles and those "long term" patients receiving 19 or more cycles (range was 19 to 32 cycles). Researchers found that there was a statistically significant advantage for "long term" treatment (median progression free survival for "short term" patients was 95 weeks (follow up of 73 weeks), but for "long term" patients the median progression free survival was not yet reached (follow up of 134 weeks)).
Because of their diffusely infiltrating nature, oligodendrogliomas cannot be completely resected and are not curable by surgical excision. If the tumor mass compresses adjacent brain structures, a neurosurgeon will typically remove as much of the tumor as he or she can without damaging other critical, healthy brain structures. Surgery may be followed up by chemotherapy, radiation, or a mix of both, but recent studies suggest that radiation does not improve overall survival (even when age, clinical data, histological grading, and type of surgery are considered). However, a recent long-term study does affirm that radiation combined with adjuvant chemotherapy is significantly more efficacious for anaplastic oligodendroglioma patients with 1p 19q co-deleted tumors and has become the new standard of care. However, it is possible that radiotherapy may prolong the overall time to progression for non-deleted tumors.
Oligodendrogliomas, like all other infiltrating gliomas, have a very high (almost uniform) rate of recurrence and gradually increase in grade over time. Recurrent tumors are generally treated with more aggressive chemotherapy and radiation therapy. Recently, stereotactic surgery has proven successful in treating small tumors that have been diagnosed early.
Long-term survival is reported in a minority of patients. With aggressive treatment and close monitoring, it is possible to outlive the typical life expectancies for both low grade and high grade oligodendrogliomas. Westergaard's
study (1997) showed that patients younger than 20 years had a median survival of 17.5 years. Another study shows a 34% survival rate after 20 years. However, as discussed above, such figures can be misleading since they do not factor in the types of treatment nor the genetic signature of the tumors. Additionally, such historic data loses significance due to the relatively long survival of patients (compared to other types of brain tumors) and the introduction of newer treatment options over time.
Brain, other CNS or intracranial tumors are the ninth most common cancer in the UK (around 10,600 people were diagnosed in 2013), and it is the eighth most common cause of cancer death (around 5,200 people died in 2012).
Oligodendrogliomas are incurable but slowly progressive malignant brain tumors. They can be treated with surgical resection, chemotherapy, radiotherapy or a combination. For some suspected low-grade (grade II) tumors, only a course of watchful waiting and symptomatic therapy is opted for. These tumors show a high frequency of co-deletions of the p and q arms of chromosome 1 and chromosome 19 respectively (1p19q co-deletion) and have been found to be especially chemosensitive with one report claiming them to be one of the most chemosensitive tumors. A median survival of up to 16.7 years has been reported for grade II oligodendrogliomas.
An ependymal tumor is a type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain). Ependymal tumors may also form in the choroid plexus (tissue in the ventricles that makes cerebrospinal fluid). Also called ependymoma.
Adult survivors of childhood cancer have some physical, psychological, and social difficulties.
Premature heart disease is a major long-term complication in adult survivors of childhood cancer. Adult survivors are eight times more likely to die of heart disease than other people, and more than half of children treated for cancer develop some type of cardiac abnormality, although this may be asymptomatic or too mild to qualify for a clinical diagnosis of heart disease.
Late effects are of two kinds: consequences of the tumor itself, and consequences of surgery and other treatments for the tumor.
Complications of not removing the coccyx may include both recurrence of the teratoma and metastatic cancer. Late malignancies usually involve incomplete excision of the coccyx and are adenocarcinoma.
Although functional disability in survivors is common, a small comparative study found a nonsignificant difference between SCT survivors and a matched control group.
In rare cases, pelvic scarring may necessitate that a pregnant woman who is a SCT survivor deliver her baby by Cesarean section.
SCTs are very rare in adults, and as a rule these tumors are benign and have extremely low potential for malignancy. This estimation of potential is based on the idea that because the tumor existed for decades prior to diagnosis, without becoming malignant, it has little or no potential to ever become malignant. For this reason, and because coccygectomy in adults has greater risks than in babies, some surgeons prefer not to remove the coccyx of adult survivors of SCT. There are case reports of good outcomes.
Embryonal teratomas most commonly occur in the sacrococcygeal region: sacrococcygeal teratoma is the single most common tumor found in newly born humans.
Of teratomas on the skull sutures, approximately 50% are found in or adjacent to the orbit. Limbal dermoid is a choristoma, not a teratoma.
Teratoma qualifies as a rare disease, but is not extremely rare. Sacrococcygeal teratoma alone is diagnosed at birth in one out of 40,000 humans. Given the current human population and birth-rate, this equals five per day or 1800 per year. Add to that number sacrococcygeal teratomas diagnosed later in life, and teratomas in other locales, and the incidence approaches ten thousand new diagnoses of teratoma per year.
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.
Children with cancer are at risk for developing various cognitive or learning problems. These difficulties may be related to brain injury stemming from the cancer itself, such as a brain tumor or central nervous system metastasis or from side effects of cancer treatments such as chemotherapy and radiation therapy. Studies have shown that chemo and radiation therapies may damage brain white matter and disrupt brain activity.