Ewing's sarcoma is more common in males (1.6 male:1 female) and usually presents in childhood or early adulthood, with a peak between 10 and 20 years of age. It can occur anywhere in the body, but most commonly in the pelvis and proximal long tubular bones, especially around the growth plates. The diaphyses of the femur are the most common sites, followed by the tibia and the humerus. Thirty percent are overtly metastatic at presentation. Patients usually experience extreme bone pain.

Signs and symptoms include: intermittent fevers, anemia, leukocytosis, increased sedimentation rate, and other symptoms of inflammatory systemic illness. Also, depending on the type, progression, and location of the tumor, great pain may occur.

According to the Bone Cancer Research Trust (BCRT), the most common symptoms are: localized pain, swelling, and sporadic bone pain with variable intensity. The swelling is most likely to be visible if the sarcoma is located on a bone near the surface of the body, but when it occurs in other places deeper in the body, like on the pelvis, it may not be visible.

Commonly affected areas include the lower limbs, back, face, mouth, and genitalia. The lesions are usually as described above, but may occasionally be plaque-like (often on the soles of the feet) or even involved in skin breakdown with resulting fungating lesions.

Associated swelling may be from either local inflammation or lymphoedema (obstruction of local lymphatic vessels by the lesion). Skin lesions may be quite disfiguring for the sufferer, and a cause of much psychosocial pathology.

A sarcoma is a cancer that arises from transformed cells of mesenchymal origin. Thus, malignant tumors made of cancellous bone, cartilage, fat, muscle, vascular, or hematopoietic tissues are, by definition, considered sarcomas. This is in contrast to a malignant tumor originating from epithelial cells, which are termed carcinoma. Human sarcomas are quite rare. Common malignancies, such as breast, colon, and lung cancer, are almost always carcinoma. The term is from the Greek "sarx" meaning "flesh".

Involvement can be common in those with transplant-related or AIDS-related KS, and it may occur in the absence of skin involvement. The gastrointestinal lesions may be silent or cause weight loss, pain, nausea/vomiting, diarrhea, bleeding (either vomiting blood or passing it with bowel motions), malabsorption, or intestinal obstruction.

Synovial sarcoma usually presents with an otherwise asymptomatic swelling or mass, although general symptoms related to malignancies can be reported such as fatigue.

Ewing sarcoma or Ewing's sarcoma () is a malignant small, round, blue cell tumor. It is a rare disease in which cancer cells are found in the bone or in soft tissue. The most common areas in which it occurs are the pelvis, the femur, the humerus, the ribs and clavicle (collar bone).

Since a common genetic locus is responsible for a large percentage of Ewing sarcoma and primitive neuroectodermal tumors, these are sometimes grouped together in a category known as the Ewing family of tumors.

Ewing sarcoma occurs most frequently in teenagers and young adults, with a male/female ratio of 1.6:1.

Although usually classified as a bone tumor, Ewing's sarcoma can have characteristics of both mesodermal and ectodermal origin, making it difficult to classify.

James Ewing (1866–1943) first described the tumour, establishing that the disease was separate from lymphoma and other types of cancer known at that time.

It presents as a slow growing mass that especially affects tendons and aponeuroses and it is deeply situated. Patients often perceive it as a lump or hard mass. It causes either pain or tenderness but only until it becomes large enough. This kind of tumor is commonly found in the extremities especially around the knee, feet and ankle. Patients diagnosed with clear cell sarcoma are usually between the ages of 20 and 40.

A synovial sarcoma (also known as: malignant synovioma) is a rare form of cancer which occurs primarily in the extremities of the arms or legs, often in close proximity to joint capsules and tendon sheaths. As one of the soft tissue sarcomas, it is one of the rarest forms of soft tissue cancer.

The name "synovial sarcoma" was coined early in the 20th century, as some researchers thought that the microscopic similarity of some tumors to synovium, and its propensity to arise adjacent to joints, indicated a synovial origin; however, the actual cells from which the tumor develops are unknown and not necessarily synovial.

Primary synovial sarcomas are most common in the soft tissue near the large joints of the arm and leg but have been documented in most human tissues and organs, including the brain, prostate, and heart.

Synovial sarcoma occurs most commonly in the young, representing

about 8% of all soft tissue sarcomas but about 15–20% of cases occur in adolescents and young adults. The peak of incidence is in the third decade of life, with males being affected more often than females (ratio around 1.2:1).

There are few early warning signs that a patient has a DSRCT. Patients are often young and healthy as the tumors grow and spread uninhibited within the abdominal cavity. These are rare tumors and symptoms are often misdiagnosed by physicians. The abdominal masses can grow to enormous size before being noticed by the patient. The tumors can be felt as hard, round masses by palpating the abdomen.

First symptoms of the disease often include abdominal distention, abdominal mass, abdominal or back pain, gastrointestinal obstruction, lack of appetite, ascites, anemia, and/or cachexia.

Other reported symptoms include unknown lumps, thyroid conditions, hormonal conditions, blood clotting, kidney or urological problems, testicle, breast, uterine, vaginal, or ovarian masses.

ASPS may exist in the patient’s body for a long time before being diagnosed. It can grow large and push aside surrounding tissues for a long time before causing any discomfort. Therefore, ASPS symptoms may either be a painless swelling, or a soreness caused by compressed nerves or muscles, affecting the range of motion in the area.

ERMS is the more common of two major subtypes of rhabdomyosarcoma, the other being alveolar rhabdomyosarcoma.

It has been informally classified as a "small round blue cell tumor" because of the characteristic microscopic appearance of its cells after histological staining with hematoxylin and eosin.

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

In oncology, small intestine cancer, also small bowel cancer and cancer of the small bowel, is a cancer of the small intestine. It is relatively rare compared to other gastrointestinal malignancies such as gastric cancer (stomach cancer) and colorectal cancer.

Small intestine cancer can be subdivided into duodenal cancer (the first part of the small intestine) and cancer of the jejunum and ileum (the later two parts of the small intestine). Duodenal cancer has more in common with stomach cancer, while cancer of the jejunum and ileum have more in common with colorectal cancer. Five year survival rates are 65%.

Several different subtypes of small intestine cancer exist. These include:

- adenocarcinoma

- gastrointestinal stromal tumor

- lymphoma

- ileal carcinoid tumor

Sarcomas are given a number of different names based on the type of tissue that they most closely resemble. For example, osteosarcoma resembles bone, chondrosarcoma resembles cartilage, liposarcoma resembles fat, and leiomyosarcoma resembles smooth muscle.

GISTs may present with trouble swallowing, gastrointestinal bleeding, or metastases (mainly in the liver). Intestinal obstruction is rare, due to the tumor's outward pattern of growth. Often, there is a history of vague abdominal pain or discomfort, and the tumor has become rather large by time the diagnosis is made.

Undifferentiated pleomorphic sarcoma (UPS), also undifferentiated pleomorphic sarcoma (PUS) and previously malignant fibrous histiocytoma (abbreviated MFH), is a type of cancer and soft tissue sarcoma.

It is considered a diagnosis of exclusion for sarcomas that cannot be more precisely categorized. Other sarcomas are cancers that form in bone and soft tissues, including muscle, fat, blood vessels, lymph vessels, and fibrous tissue (such as tendons and ligaments).

Low-grade fibromyxoid sarcoma (LGFMS) is a rare type of low grade sarcoma first described by Harry Evans in 1987. It is characterized by a long and indolent clinical course and the possibility of local recurrence or distant metastases in a subset of patients. Unlike many other types of cancer, low grade fibromyxoid sarcoma can metastasize after many years, sometimes decades after the initial presentation of the tumor.

Although ASPS displays a relatively indolent course, the ultimate prognosis is poor and is often characterized by late metastases.

UPS occurs most commonly in the extremities and retroperitoneum, but has been reported in other sites. Metastasis occurs most frequently in the lungs (90%), bones (8%), and liver (1%).

In the extremities, it presents itself as a painless enlarging soft tissue mass.

When the tumor is large and there is presence of necrosis and local recurrence, the prognosis is poor. Presence of metastasis occurs in more than 50% cases and the common places of its occurrence are the bone, lymph node and lungs. Five-year survival rates, which are reported to be between 50-65%, can be misleading because the disease is prone to late metastasis or recurrence. Ten and twenty-year survival rates are 33% and 10%, respectively.

Fibrosarcoma (fibroblastic sarcoma) is a malignant mesenchymal tumour derived from fibrous connective tissue and characterized by the presence of immature proliferating fibroblasts or undifferentiated anaplastic spindle cells in a storiform pattern. It is usually found in males aged 30 to 40 . It originates in fibrous tissues of the bone and invades long or flat bones such as femur, tibia, and mandible. It also involves periosteum and overlying muscle.

Dermatofibrosarcoma protuberans can begin as a minor firm area of skin most commonly about to 1 to 5 cm in diameter. It can resemble a bruise, birthmark, or pimple. It is a slow growing tumor and is usually found on the torso but can also be found on the arms, legs, head and neck. About 90% of DFSPs are low grade sarcomas. About 10% are mixed; they contain a high-grade sarcomatous component (DFSP-FS); therefore, they are considered to be intermediate-grade sarcomas. DFSPs rarely lead to a metastasis (fewer than 5% do metastasise), but DFSPs can recur locally. DFSPs most often arise in patients who are in their thirties, but sometimes have been described in children or the elderly.

Dermatofibrosarcoma protuberans (DFSP)

is a very rare tumor. It is a rare neoplasm of the dermis layer of the skin, and is classified as a sarcoma. There is only about one case per million per year. DFSP is a fibrosarcoma, more precisely a cutaneous soft tissue sarcoma. In many respects, the disease behaves as a benign tumor, but in 2–5% of cases it can metastasize, so it should be considered to have malignant potential. It occurs most often in adults in their thirties; it has been described congenitally, in children, and the elderly. It accounts for approximately 2–6% of soft tissue sarcoma cancers.

Congenital mesoblastic nephroma typically (76% of cases) presents as an abdominal mass which is detected prenatally (16% of cases) by ultrasound or by clinical inspection (84% of cases) either at birth or by 3.8 years of age (median age ~1 month). The neoplasm shows a slight male preference. Concurrent findings include hypertension (19% of cases), polyhydramnios (i.e. excess of amniotic fluid in the amniotic sac) (15%), hematuria (11%), hypercalcemia (4%), and elevated serum levels of the kidney-secreted, hypertension-inducing enzyme, renin (1%). Congenital anomalies have been reported in 11 patients: 6 with genitourinary anomalies, 2 with gastrointestinal anomalies, 1 with hydrocephalus, and 1 with the Beckwith–Wiedemann syndrome. The vast majority of patients present with localized (i.e. non-metastatic) disease. Most patients' disease is classified at presentation as stage I or II (i.e. localized), few patients present with stage III (i.e. locally advanced/infiltrating), and virtually no patients present with stage IV (metastases present or V (i.e. tumors in both kidneys) disease (see staging of renal cancer).

Desmoplastic small-round-cell tumor is an aggressive and rare cancer that primarily occurs as masses in the abdomen. Other areas affected may include the lymph nodes, the lining of the abdomen, diaphragm, spleen, liver, chest wall, skull, spinal cord, large intestine, small intestine, bladder, brain, lungs, testicles, ovaries, and the pelvis. Reported sites of metastatic spread include the liver, lungs, lymph nodes, brain, skull, and bones.

The tumor is classified as a soft tissue sarcoma. It is considered a childhood cancer that predominantly strikes boys and young adults. The disease rarely occurs in females, but when it does the tumors can be mistaken for ovarian cancer.

In dogs, mast cell tumors are the most frequent round cell tumor.