Patients who have been diagnosed with ARMS often have poor outcomes. The four year survival rate without remission for local ARMS tumors is 65 percent, while the four year survival rate with metastatic ARMS is only 15 percent. Patients who have metastatic ARMS positive with PAX3-FOXO1 fusion often have a poorer outcome than patients positive with PAX7-FOXO1 fusion, with a four-year survival rate of 8 percent and 75 percent respectively. Other variables affect the four year survival rate, such as, primary tumor site, size of primary tumor, amount of local invasion, number of distal lymph nodes spread to, and whether metastasis has occurred. Prognosis for patients who have primary tumor sites within the bones often have higher survival rates and respond well to treatment options. While patients who have primary tumor sites within the nasopharynx region with metastases to the breast have very poor outcomes. Patients who are fusion protein negative with low risk clinical features should be treated with reduced therapy, while patients who are fusion protein positive with low risk clinical features should be treated as an intermediate risk and have more intensive therapy regimens.

Childhood rhabdomyosarcoma has been fatal. Recovery rates have increased by 50 percent since 1975. In children five years of age or younger survival rates are up to 65 percent. In adolescents younger than 15 years old, the survival rate has increased up to 30 percent.

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.

Regardless of location, all rhabdoid tumours are highly aggressive, have a poor prognosis, and tend to occur in children less than two years of age.

An estimated 3% of pediatric brain tumors are AT/RTs, although this percentage may increase with better differentiation between PNET/medulloblastoma tumors and AT/RTs.

As with other CNS tumors, more males are affected than females (ratio 1.6:1). The ASCO study showed a 1.4:1 male to female ratio.

Staging attempts to distinguish patients with localized from those with metastatic disease. Most commonly, metastases occur in the chest, bone and/or bone marrow. Less common sites include the central nervous system and lymph nodes.

Five-year survival for localized disease is 70% to 80% when treated with chemotherapy. Prior to the use of multi-drug chemotherapy, long-term survival was less than 10%. The development of multi-disciplinary therapy with chemotherapy, irradiation, and surgery has increased current long-term survival rates in most clinical centers to greater than 50%. However, some sources state it is 25–30%.

Retrospective research in patients led by Idriss M. Bennani-Baiti (Cancer Epigenetics Society) showed that two chemokine receptors, CXCR4 and CXCR7, can be used as molecular prognosis factors. Patients who express low levels of both chemokine receptors have the highest odds of long-term survival with >90% survival at 5 years post-diagnosis versus <30% survival at 5 years for patients with very high expression levels of both receptors.

The prognosis for rhabdomyosarcoma has improved greatly in recent decades, with over 70% of patients surviving for five years after diagnosis.

Alveolar rhabdomyosarcoma (ARMS) is a sub-type of the rhabdomyosarcoma soft tissue cancer family whose lineage is from mesenchymal cells and are related to skeletal muscle cells. ARMS tumors resemble the alveoli tissue that can be found in the lungs. Tumor location varies from patient to patient, but is commonly found in the head and neck region, male and female urogenital tracts, the torso, and extremities. Two fusion proteins can be associated with ARMS, but are not necessary, PAX3-FKHR (now known as FOXO1). and PAX7-FKHR. In children and adolescents ARMS accounts for about 1 percent of all malignancies, has an incidence rate of 1 per million, and most cases occur sporadically with no genetic predisposition.

Congenital mesoblastic nephroma, while rare, is the most common kidney neoplasm diagnosed in the first three months of life and accounts for 3-5% of all childhood renal neoplasms. This neoplasm is generally non-aggressive and amenable to surgical removal. However, a readily identifiable subset of these kidney tumors has a more malignant potential and is capable of causing life-threatening metastases. Congenital mesoblastic nephroma was first named as such in 1967 but was recognized decades before this as fetal renal hamartoma or leiomyomatous renal hamartoma.

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.

Metastatic spread is noted in roughly one-third of the AT/RT cases at the time of diagnosis, and tumors can occur anywhere throughout the CNS. The ASCO study of the 188 documented AT/RT cases prior to 2004 found 30% of the cases had metastasis at diagnosis. Metastatic spread to the meninges (leptomenigeal spread sometimes referred to as sugar coating) is common both initially and with relapse. Average survival times decline with the presence of metastasis. Primary CNS tumors generally metastasize only within the CNS.

One case of metastatic disease to the abdomen via ventriculoperitoneal shunt has been reported with AT/RT . Metastatic dissemination via this mechanism has been reported with other brain tumors, including germinomas, medulloblastomas, astrocytomas, glioblastomas, ependymomas, and endodermal sinus tumors. Guler and Sugita separately reported cases of lung metastasis without a shunt.

Malignant rhabdoid tumour (MRT) is a very aggressive form of tumour originally described as a variant of Wilms' tumour, which is primarily a kidney tumour that occurs mainly in children.

MRT was first described as a variant of Wilms' tumour of the kidney in 1978. MRTs are a rare and highly malignant childhood neoplasm. Later rhabdoid tumours outside the kidney were reported in many tissues including the liver, soft tissue, and the central nervous system. Several cases of primary intracranial MRT have been reported since its recognition as a separate entity in 1978. The term "rhabdoid" was used due to its similarity with rhabdomyosarcoma under the light microscope. The exact pathogenesis of MRT is unknown.

The cerebellum is the most common location for primary intracerebral MRT (i.e., AT/RT). Biggs et al. were first to report a primary intracranial MRT around 1987.

Although the cell of origin is not known, cytogenetic studies have suggested a common genetic basis for rhabdoid tumours regardless of location with abnormalities in chromosome 22 commonly occurring.

Esthesioneuroblastoma is a slow developing but malignant tumor with high reoccurrence rates because of its anatomical position. The tumor composition, location and metastatic characteristics as well as the treatment plan determine prognosis. Common clinical classification systems for esthesioneuroblastoma include the Kadish classification and the Dulguerov classfictation. Histopathological characteristics on top of Kadish classification can further determine cancer prognosis. In severe, Kadish class C tumors, Haym's grades of pathology are important for prognosis. Patients with low grade Kadish class C tumors have a 10-year survival rate of 86 percent compared to patients with high grade class C tumors who have a survival rate of 28 percent. Surgically treated patients with high grade tumors are more likely to experience leptomeningeal metastases or involvement of the cerebral spinal fluid unlike patients with low grade tumors who usually only see local recurrence. Survival rates for treated esthesioneuroblastoma are best for surgery with radiotherapy (65%), then for radiotherapy and chemotherapy (51%), just surgery (48%), surgery, radiotherapy and chemotherapy (47) and finally just radiotherapy (37%). From the literature, radiotherapy and surgery seem to boast the best outcome for patients. However, it is important to understand that to some degree, prognosis is related to tumor severity. More progressed, higher grade tumors would result in chemotherapy or radiotherapy as the only treatment. It is no surprise that the prognosis would be worse in these cases.

Spindle cell rhabdomyosarcoma is a subtype of embryonal rhabdomyosarcoma first described by Cavazzana, Schmidt and Ninfo in 1992. This subtype has a more favorable clinical course and prognosis than usual embryonal rhabdomyosarcoma. Spindle cell rhabdomyosarcoma typically occurs in young males and most commonly occurs in paratesticular soft tissue, followed by the head and neck.

Ewing's sarcomas represent 16% of primary bone sarcomas. In the United States, they are most common in the second decade of life, with a rate of 0.3 cases per million in children under 3 years of age, and as high as 4.6 cases per million in adolescents aged 15–19 years. Internationally, the annual incidence rate averages less than 2 cases per million children. In the United Kingdom, an average of six children per year are diagnosed, mainly males in early stages of puberty. Due to the prevalence of diagnosis during teenage years, a link may exist between the onset of puberty and the early stages of this disease, although no research confirms this hypothesis.

The oldest known patient diagnosed was at age 76, from the Mercer County, New Jersey, area.

A grouping of three unrelated teenagers in Wake Forest, NC, have been diagnosed with Ewing's sarcoma. All three children were diagnosed in 2011 and all attended the same temporary classroom together while the school underwent renovation. A fourth teenager living nearby was diagnosed in 2009. The odds of this grouping are considered significant.

Ewing's sarcoma shows striking differences in incidence across human populations and is about 10- to 20-fold more common in populations from European descent as compared to Africans. Consistently, a genome-wide association study (GWAS) conducted in several hundreds European individuals with Ewing's sarcoma and genetically-matched healthy controls identified three susceptibility loci located on chromosomes 1, 10 and 15. A continuative study discovered that the Ewing's sarcoma susceptibility gene "EGR2", which is located within the chromosome 10 susceptibility locus, is regulated by the "EWSR1-FLI1" fusion oncogene via a GGAA-microsatellite.

Ewing's sarcoma is the second most common bone cancer in children and adolescents, with poor prognosis and outcome in ~70% of initial diagnoses and 10–15% of relapses.

Sarcomas are quite rare with only 15,000 new cases per year in the United States. Sarcomas therefore represent about one percent of the 1.5 million new cancer diagnoses in that country each year.

Sarcomas affect people of all ages. Approximately 50% of bone sarcomas and 20% of soft tissue sarcomas are diagnosed in people under the age of 35. Some sarcomas, such as leiomyosarcoma, chondrosarcoma, and gastrointestinal stromal tumor (GIST), are more common in adults than in children. Most high-grade bone sarcomas, including Ewing's sarcoma and osteosarcoma, are much more common in children and young adults.

Rhabdomyosarcoma is the most common soft-tissue sarcoma in children as well as the third most common solid tumor in children. Recent estimates place the incidence of the disease at approximately 4.5 case per 1 million children/adolescents with approximately 250 new cases in the United States each year. With the vast majority of cases of RMS occurring in children or adolescents, two-thirds of reported cases occur in youths under the age of 10. RMS also occurs slightly more often in males than in females, with a ratio of approximately 1.3–1.5:1. In addition, slightly lower prevalence of the disease has been reported in black and Asian children relative to white children. In most cases, there are no clear predisposing risk factors for the development of RMS. It tends to occur sporadically with no obvious cause. However, RMS has been correlated with familial cancer syndromes and congenital abnormalities including neurofibromatosis type 1, Beckwith-Wiedemann syndrome, Li–Fraumeni syndrome, cardio-facio-cutaneous syndrome, and Costello syndrome. It has also been associated with parental use of cocaine and marijuana.

Esthesioneuroblastoma accounts for 2% of all intranasal tumors with an incidence of 0.4 cases per million people. Fewer than 700 cases of esthesioneuroblastoma have been seen in the US since 1988. Fewer than 400 unique cases have been reported globally. Esthesioneuroblastoma can occur at any time, with peak occurrence reported in the second and sixth decade of life.

There are multiple genetic lesions associated with rhabdomyosarcoma, but there has been little consistent data demonstrating an association between specific genetic abnormalities and outcome. However, alveolar and embryonal types of RMS can be distinguished cytogenetically, and identification of specific genetic lesions can allow for accurate classification of the ARMS subtype when the histopathological findings are equivocal or unclear. This is valuable for clinical practice as the alveolar type presents a higher risk to the patient and will often require more aggressive treatment than the embryonal type. Up to 90% of alveolar RMS cases present with a translocations of t(2;13)(q35,q14) or, less commonly, t(1;13)(p36,q15). Both involve the translocation of a DNA binding domain of "PAX," a member of the Paired Box family of transcription factors, to a transactivation site on "FKHR", a member of the forkhead/HNF-3 transcription factor family. The t(2;13) translocation results in a fusion of the "PAX3" gene with "FKHR", while the t(1;13) translocation involves the fusion of "PAX7" with "FKHR". "PAX3" has a demonstrated role in muscle cell development, which supports its potential role in RMS. The t(2;13) translocation can result in the "PAX3-FKHR" fusion product, which is indicative of classic cystic ARMS. Cases of ARMS presenting with this fusion protein are said to be fusion-positive and are associated with a poorer prognosis than fusion-negative ARMS. Fortunately, the fusion protein presents a potential therapeutic target, but more research is needed to clarify the role of "PAX3-FKHR" in ARMS.

Embryonal RMS usually presents with a loss of heterozygosity (LOH) in the short arm of chromosome 11 (p11,15.5). This region is associated with multiple oncogenes, and the potential loss-of-function of this region is likely associated with the loss of a tumor suppressor. However, the specific consequences of this LOH at (p11,15.5) have yet to be determined. The short arm of chromosome 11 is also the site of the insulin-like growth factor 2 gene (IGF-2), which is often over-expressed in RMS.

"p"53 loss-of-function is associated with many cancers including rhabdomyosarcoma, and approximately 50% of RMS cases have been shown to carry some form of mutation to the p53 gene. Other oncogenes often associated with rhabdomyosarcoma, albeit with less frequency, include N"-myc", N"-ras", K"-ras," p"16," and c-"Met." However, it is unclear whether the mutation of the genes is directly related to the development of RMS. One study showed a that 35% of embryonal RMS tumors contained activating mutations in either N- or K-"ras," and it is worth noting that "ras" activation has been shown to block myogenic differentiation, which could help explain its potential role in rhabdomyosarcogenesis.

Based on a survey of >800, surgical removal of the entire involved kidney plus the peri-renal fat appeared curative for the majority of all types of mesoblastic nephroma; the patient overall survival rate was 94%. Of the 4% of non-survivors, half were due to surgical or chemotherapeutic treatments. Another 4% of these patients suffered relapses, primarily in the local area of surgery rare cases of relapse due to lung or bone metastasis.. About 60% of these recurrent cases had a complete remission following further treatment. Recurrent disease was treated with a second surgery, radiation, and/or chemotherapy that often vincristine and actinomycin treatment. Removal of the entire afflicted kidney plus the peri-renal fat appears critical to avoiding local recurrences. In general, patients who were older than 3 months of age at diagnosis or had the cellular form of the disease, stage III disease, or involvement of renal lymph nodes had a higher recurrence rate. Among patients with these risk factors, only those with lymph node involvement are recommended for further therapy.

It has been suggested that mesoblastic nephroma patients with lymph node involvement or recurrent disease might benefit by adding the ALK inhibitor, crizotinib, or a tyrosine kinase inhibitor, either larotrectinib or entrectinib, to surgical, radiation, and/or chemotherapy treatment regimens. These drugs inhibit NTRK3's tyrosine kinase activity. Crizotinib has proven useful in treating certain cases of acute lymphoblastic leukemia that are associated with the "ETV6-NTRK3" fusion gene while larotrectinib and entrectinib have been useful in treating various cancers (e.g. a metastatic sarcoma, papillary thyroid cancer, non-small-cell lung carcinoma, gastrointestinal stromal tumor, mammary analog secretory carcinoma, and colorectal cancer) that are driven by mutated, overly active tyrosine kinases. Relevant to this issue, a 16-month-old girl with infantile fibrosarcoma harboring the "ETV6–NTRK3" fusion gene was successfully trated with larotrectinib. The success of these drugs, howwever, will likely depend on the relative malignancy-promoting roles of ETV6-NTRK3 protein's tyrosine kinase activity, the lose of ETV6-related transcription activity accompanying formation of ETV6-NTRK3 protein, and the various trisomy chromosomes that populate mesoblastic nephroma.

NUT carcinoma (formerly NUT midline carcinoma), is a rare genetically defined, very aggressive squamous cell epithelial cancer that usually arises in the midline of the body and is characterized by a chromosomal rearrangement in the nuclear protein in testis gene. In approximately 75% of cases, the coding sequence of "NUTM1" on chromosome 15q14 is fused to "BRD4" or "BRD3", which creates a chimeric gene that encodes the "BRD-NUT" fusion protein. The remaining cases, the fusion of NUTM1 is to an unknown partner gene, usually called "NUT"-variant.

Embryonal rhabdomyosarcoma (ERMS) is a rare histological form of cancer of connective tissue wherein the mesenchymally-derived malignant cells resemble the primitive developing skeletal muscle of the embryo. It is the most common soft tissue sarcoma occurring in children.

In addition to being named based on the tissue of origin, sarcomas are also assigned a grade (low, intermediate, or high) based on the presence and frequency of certain cellular and subcellular characteristics associated with malignant biological behavior. Low grade sarcomas are usually treated surgically, although sometimes radiation therapy or chemotherapy are used. Intermediate and high grade sarcomas are more frequently treated with a combination of surgery, chemotherapy and/or radiation therapy. Since higher grade tumors are more likely to undergo metastasis (invasion and spread to locoregional and distant sites), they are treated more aggressively. The recognition that many sarcomas are sensitive to chemotherapy has dramatically improved the survival of patients. For example, in the era before chemotherapy, long-term survival for patients with localized osteosarcoma was only approximately 20%, but now has risen to 60–70%.

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.

Childhood rhabdomyosarcoma is difficult to diagnose. Factors that increase the likelihood of this cancer include Li-Fraumeni syndrome, type one Neurofibromatosis, Beckwith-Wiedemann syndrome, Costello syndrome, and Noonan syndrome. Each contribute to deformations of bones, tissue, and muscles.