Patient response to treatment will vary based on age, health, and the tolerance to medications and therapies.

Metastasis occurs in about 39% of patients, most commonly to the lung. Features associated with poor prognosis include a large primary tumor (over 5 cm across), high grade disease, co-existent neurofibromatosis, and the presence of metastases.

It is a rare tumor type, with a relatively poor prognosis in children.

In addition, MPNSTs are extremely threatening in NF1. In a 10-year institutional review for the treatment of chemotherapy for MPNST in NF1, which followed the cases of 1 per 2,500 in 3,300 live births, chemotherapy did not seem to reduce mortality, and its effectiveness should be questioned. Although with recent approaches with the molecular biology of MPNSTs, new therapies and prognostic factors are being examined.

Malignant germ cell tumors of the mediastinum are uncommon, representing only 3 to 10% of tumors originating in the mediastinum. They are much less common than germ cell tumors arising in the testes, and account for only 1 to 5% of all germ cell neoplasms.

Syndromes associated with mediastinal germ cell tumors include Hematologic Neoplasia and Klinefelter's syndrome.

The treatment of a Pancoast lung cancer may differ from that of other types of non-small cell lung cancer. Its position and close proximity to vital structures (such as nerves and spine) may make surgery difficult. As a result, and depending on the stage of the cancer, treatment may involve radiation and chemotherapy given prior to surgery (neoadjuvant treatment).

Surgery may consist of the removal of the upper lobe of a lung together with its associated structures (subclavian artery, vein, branches of the brachial plexus, ribs and vertebral bodies), as well as mediastinal lymphadenectomy. Surgical access may be via thoracotomy from the back or the front of the chest and modifications

A nervous system neoplasm is a tumor affecting the nervous system. Types include:

- Nerve sheath tumor

- Brain tumor

- Arachnoid cyst

- Optic nerve glioma

Giant-cell lung cancers have long been considered to be exceptionally aggressive malignancies that grow very rapidly and have a very poor prognosis.

Many small series have suggested that the prognosis of lung tumors with giant cells is worse than that of most other forms of non-small-cell lung cancer (NSCLC), including squamous cell carcinoma, and spindle cell carcinoma.

The overall five-year survival rate in GCCL varies between studies but is generally considered to be very low. The (US) Armed Forces Institute of Pathology has reported a figure of 10%, and in a study examining over 150,000 lung cancer cases, a figure of 11.8% was given. However, in the latter report the 11.8% figure was based on data that included spindle cell carcinoma, a variant which is generally considered to have a less dismal prognosis than GCCL. Therefore, the likely survival of "pure" GCCL is probably lower than the stated figure.

In the large 1995 database review by Travis and colleagues, giant-cell carcinoma has the third-worst prognosis among 18 histological forms of lung cancer. (Only small-cell carcinoma and large-cell carcinoma had shorter average survival.)

Most GCCL have already grown and invaded locally and/or regionally, and/or have already metastasized distantly, and are inoperable, at the time of diagnosis.

Although reliable and comprehensive incidence statistics are nonexistent, LCLC-RP is a rare tumor, with only a few hundred cases described in the scientific literature to date. LCLC's made up about 10% of lung cancers in most historical series, equating to approximately 22,000 cases per year in the U.S. Of these LCLC cases, it is estimated that about 1% will eventually develop the rhabdoid phenotype during tumor evolution and progression. In one large series of 902 surgically resected lung cancers, only 3 cases (0.3%) were diagnosed as LCLC-RP. In another highly selected series of large-cell lung carcinoma cases, only 4 of 45 tumors (9%) were diagnosed as the rhabdoid phenotype using the 10% criterion, but another 10 (22%) had at least some rhabdoid cell formation. It appears likely, therefore, that LCLC-RP probably comprises between 0.1% and 1.0% of all lung malignancies.

Similar to nearly all variants of lung carcinoma, large cell lung carcinoma with rhabdoid phenotype appears to be highly related to tobacco smoking. It also appears to be significantly more common in males than in females.

The majority of patients with neurocutaneous melanosis are asymptomatic and therefore have a good prognosis with few complications. Most are not diagnosed, so definitive data in not available. For symptomatic patients, the prognosis is far worse. In patients without the presence of melanoma, more than 50% die within 3 years of displaying symptoms. While those with malignancy have a mortality rate of 77% with most patients displaying symptoms before the age of 2.

The presence of a Dandy-Walker malformation along with neurocutaneous melanosis, as occurs in 10% of symptomatic patients, further deteriorates prognosis. The median survival time for these patients is 6.5 months after becoming symptomatic.

Fibrosarcoma occurs most frequently in the mouth in dogs . The tumor is locally invasive, and often recurs following surgery . Radiation therapy and chemotherapy are also used in treatment. Fibrosarcoma is also a rare bone tumor in dogs.

In cats, fibrosarcoma occurs on the skin. It is also the most common vaccine-associated sarcoma. In 2014, Merial launched Oncept IL-2 in Europe for the management of such feline fibrosarcomas.

Perivascular epithelioid cell tumour, also known as PEComa or PEC tumour, is a family of mesenchymal tumours consisting of perivascular epithelioid cells (PECs). These are rare tumours that can occur in any part of the human body.

The cell type from which these tumours originate remains unknown. Normally, no perivascular epitheloid cells exist; the name refers to the characteristics of the tumour when examined under the microscope.

Establishing the malignant potential of these tumours remains challenging although criteria have been suggested; some PEComas display malignant features whereas others can cautiously be labeled as having 'uncertain malignant potential'. The most common tumours in the PEComa family are renal angiomyolipoma and pulmonary lymphangioleiomyomatosis, both of which are more common in patients with tuberous sclerosis complex. The genes responsible for this multi-system genetic disease have also been implicated in other PEComas.

Many PEComa types shows a female predominance in the sex ratio.

A study by You et al. was only able to evaluate the 47 documented cases that have been made to date. According to this study, intraocular schwannomas are more prevalent in females as compared to males with a ratio of 3:1. Additionally, individuals are more likely to present with intraocular schwannomas at a younger age than with uveal melanomas, the most common intraocular tumor. According to the participants evaluated in this study, the average age of occurrence was 37 years old, however, it is important to note that the age range documented represented individuals 9–76 years old.

An intraneural perineurioma is a rare benign tumor within the sheath of a single nerve that grows but typically does not recur or metastasize. These lesions are only composed of perineurial cells, cloned from a single cell. They are distinct from schwannoma and neurofibroma.

"Intraneural perineurioma is a neoplastic proliferation of perineurial cells with unique immunohistochemistry and ultrastructural features, and it is distinct from other onion bulb Schwann cell-derived entities. Despite harboring molecular abnormalities of the long arm of chromosome 22, intraneural perineurioma has not been associated with neurofibromatosis."

Orbital dermoid cysts are benign which are typically found at the junction of sutures, most commonly at the fronto-zygomatic suture. Large deep orbital dermoid cysts can cause pressure effects on the muscles and optic nerve, leading to diplopia and loss of vision.

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%.

Malignant triton tumor (MTT) is a relatively rare, aggressive tumor made up of both malignant schwannoma cells and malignant rhabdomyoblasts. It's classified as a malignant peripheral nerve sheath tumor with rhabdomyosarcomatous differentiation.

The unusual name "triton" was first used in reference to observation of supernumerary limbs containing bone and muscle growing on the backs of triton salamanders after the implantation of sciatic nerve tissue.

The precursor cell of PEComas is currently unknown; there is no normal counterpart "perivascular epitheloid cell". Genetically, PECs are linked to the tuberous sclerosis genes TSC1 and TSC2, although this link is stronger for angiomyolipoma and lymphangioleiomyomatosis than for other members of the PEComa family.

Tumors in the eye and orbit can be benign like dermoid cysts, or malignant like rhabdomyosarcoma and retinoblastoma.

Surgery, with as wide a margin of removal as possible, has generally been the most effective and preferred way to attack LMS. If surgical margins are narrow or not clear of tumor, however, or in some situations where tumor cells were left behind, chemotherapy or radiation has been shown to give a clear survival benefit. While LMS tends to be resistant to radiation and chemotherapy, each case is different and results can vary widely.

LMS of uterine origin do frequently, but not always respond to hormonal treatments.

The causes of meningiomas are not well understood. Most cases are sporadic, appearing randomly, while some are familial. Persons who have undergone radiation, especially to the scalp, are more at risk for developing meningiomas, as are those who have had a brain injury. Atomic bomb survivors from Hiroshima had a higher than typical frequency of developing meningiomas, with the incidence increasing the closer that they were to the site of the explosion. Dental x-rays are correlated with an increased risk of meningioma, in particular for people who had frequent dental x-rays in the past, when the x-ray dose of a dental x-ray was higher than in the present.

Having excess body fat increases the risk.

A 2012 review found that mobile telephone use was unrelated to meningioma.

People with neurofibromatosis type 2 (NF-2) have a 50% chance of developing one or more meningiomas.

Ninety-two percent of meningiomas are benign. Eight percent are either atypical or malignant.

Pleomorphic adenoma is a common benign salivary gland neoplasm characterised by neoplastic proliferation of parenchymatous glandular cells along with myoepithelial components, having a malignant potentiality. It is the most common type of salivary gland tumor and the most common tumor of the parotid gland. It derives its name from the architectural Pleomorphism (variable appearance) seen by light microscopy. It is also known as "Mixed tumor, salivary gland type", which describes its pleomorphic appearance as opposed to its dual origin from epithelial and myoepithelial elements.

Granular cell tumor is a tumor that can develop on any skin or mucosal surface, but occurs on the tongue 40% of the time.

It is also known as Abrikossoff's tumor, Granular cell myoblastoma, Granular cell nerve sheath tumor, and Granular cell schwannoma.)

Many individuals have meningiomas, but remain asymptomatic, so the meningiomas are discovered during an autopsy. One to two percent of all autopsies reveal meningiomas that were unknown to the individuals during their lifetime, since there were never any symptoms. In the 1970s, tumors causing symptoms were discovered in 2 out of 100,000 people, while tumors discovered without causing symptoms occurred in 5.7 out of 100,000, for a total incidence of 7.7/100,000. With the advent of modern sophisticated imaging systems such as CT scans, the discovery of asymptomatic meningiomas has tripled.

Meningiomas are more likely to appear in women than men, though when they appear in men, they are more likely to be malignant. Meningiomas may appear at any age, but most commonly are noticed in men and women age 50 or older, with meningiomas becoming more likely with age. They have been observed in all cultures, Western and Eastern, in roughly the same statistical frequency as other possible brain tumors.

LCLC-RP are considered to be especially aggressive tumors with a dismal prognosis. Many published cases have shown short survival times after diagnosis. Some studies suggest that, as the proportion of rhabdoid cells in the tumor increases, the prognosis tends to worsen, although this is most pronounced when the proportion of rhabdoid cells exceeds 5%. With regard to "parent" neoplasms other than LCLC, adenocarcinomas with rhabdoid features have been reported to have worse prognoses than adenocarcinomas without rhabdoid features, although an "adenocarcinoma with rhabdoid phenotype" tumor variant has not been specifically recognized as a distinct entity under the WHO-2004 classification system.

Interestingly, there are case reports of rhabdoid carcinomas recurring after unusually long periods, which is unusual for a fast-growing, aggressive tumor type. One report described a very early stage patient whose tumor recurred 6 years after initial treatment. Although rapidly progressive, fulminant courses seem to be the rule in this entity, long-term survival has also been noted, even post-metastectomy in late stage, distant metastatic disease.

The median survival time of patients without treatment is four to six weeks. The best prognosis are seen from NM due to breast cancer with the median overall survival of no more than six months after diagnosis of NM. Death are generally due to progressive neurological dysfunction. Treatment is meant to stabilize neurological function and prolong survival. Neurological dysfunction usually cannot be fixed but progressive dysfunction can be halted and survival may be increased to four to six months.

Factors that lower survival:

Much of prognosis can be determined from the damage due to primary cancer. Negative hormone receptor status, poor performance status, more than 3 chemotherapy regimes, and high Cyfra 21-1 level at diagnosis, all indicates lower survival period of patients with NM. Cyfra 21-1 is a fragment of the cytokeratin 19 and may reflect the tumor burden within the CSF.

A nerve sheath tumor is a type of tumor of the nervous system (nervous system neoplasm) which is made up primarily of the myelin surrounding nerves.

A peripheral nerve sheath tumor (PNST) is a nerve sheath tumor in the peripheral nervous system. Benign peripheral nerve sheath tumors include schwannomas and neurofibromas.

A malignant peripheral nerve sheath tumor (MPNST) is a cancerous peripheral nerve sheath tumor.

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.