Soft tissue sarcoma A soft-tissue sarcoma (STS) is a malignant tumour, a type of cancer, that develops in soft tissue. A soft tissue sarcoma is often a painless mass that grows slowly over months or years. They may be superficial or deep-seated. Any such unexplained ...

refers to a broad group of

tumors A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

that originate from connective tissues. They tend to have similar

histologic Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...

appearance and biological behavior, and can be either

benign Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous benign tumor, ''benign'' tumor in that a malign ...

malignant Malignancy () is the tendency of a medical condition to become progressively worse. Malignancy is most familiar as a characterization of cancer. A ''malignant'' tumor contrasts with a non-cancerous ''benign'' tumor in that a malignancy is not s ...

. Soft tissue sarcomas can arise in any part of the pet's body but skin and subcutaneous tumors are the most commonly observed. Soft-tissue sarcomas comprise approximately 15% of all skin and subcutaneous tumors in dogs and approximately 7% of all skin and subcutaneous

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s. The variety of different tumors that fall under the category of soft tissue sarcomas includes

fibrosarcoma 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 patte ...

hemangiopericytoma A hemangiopericytoma is a type of soft-tissue sarcoma that originates in the pericytes in the walls of capillaries. When inside the nervous system, although not strictly a meningioma tumor, it is a meningeal tumor with a special aggressive behavior ...

liposarcoma Liposarcomas are the most common subtype of soft tissue sarcomas, accounting for at least 20% of all sarcomas in adults. Soft tissue sarcomas are rare neoplasms with over 150 different histological subtypes or forms. Liposarcomas arise from the pr ...

rhabdomyosarcoma Rhabdomyosarcoma (RMS) is a highly aggressive form of cancer that develops from mesenchymal cells that have failed to fully differentiate into myocytes of skeletal muscle. Cells of the tumor are identified as rhabdomyoblasts. There are four subt ...

leiomyosarcoma Leiomyosarcoma is a malignant (cancerous) smooth muscle tumor. A benign tumor originating from the same tissue is termed leiomyoma. While leiomyosarcomas are not thought to arise from leiomyomas, some leiomyoma variants' classification is evolvi ...

, malignant fibrous

histiocytoma A histiocytoma is a Tumor, tumour consisting of histiocytes. Histiocytes are Cells (biology), cells that are a part of the mononuclear phagocytic system, a part of the body's immune system that consists of phagocytic cells, which are responsible f ...

, malignant nerve sheath tumors,

myxosarcoma Myxosarcoma is a rare malignant tumor of the heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, whil ...

myxofibrosarcoma Myxofibrosarcoma (MFS), although a rare type of tumor, is one of the most common soft tissue sarcomas, i.e. cancerous tumors, that develop in the soft tissues of elderly individuals. Initially considered to be a type of histiocytoma termed fibrou ...

, mesenchymoma, and spindle cell tumor.

Signs and symptoms

Soft tissue sarcomas are often detected as a firm mass located on the trunk, limbs, or oral cavity. The symptoms depend on the tumor's location and degree of invasion. For example, tumors in the gastrointestinal tract may cause vomiting, diarrhea, or weight loss. Tumors in the mouth may cause bad breath, difficulty swallowing, or lack of appetite. Tumors arising in the

peripheral nerves The peripheral nervous system (PNS) is one of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system (CNS). The PNS consists of nerves and ganglia, which lie outside the brain a ...

may cause pain,

lameness A limp is a type of asymmetric abnormality of the gait. Limping may be caused by pain, weakness, neuromuscular imbalance, or a skeletal deformity. The most common underlying cause of a painful limp is physical trauma; however, in the absence ...

, or neurological symptoms.

Diagnosis

Prior to initiating any type of treatment, it is important to gather as much information as possible regarding the tumor's tissue origin, size, site, histologic grade (level of aggressiveness) and whether it has spread to other organs. To definitively confirm the diagnosis of a soft-tissue sarcoma, the

veterinarian A veterinarian (vet), also known as a veterinary surgeon or veterinary physician, is a medical professional who practices veterinary medicine. They manage a wide range of health conditions and injuries in non-human animals. Along with this, vet ...

will have to perform

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...

for histopathologic evaluation. Additional tests are performed in order to evaluate how advanced the cancer is. These tests generally involve blood and serum biochemical tests, chest

X-rays An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 Picometre, picometers to 10 Nanometre, nanometers, corresponding to frequency, ...

to check for

metastasis Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, ...

to the lungs and imaging studies .g._ultrasound,_computed_tomography.html" ;"title="ultrasound.html" ;"title=".g. ultrasound">.g. ultrasound, computed tomography">ultrasound.html" ;"title=".g. ultrasound">.g. ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI)] to evaluate the extent of the disease.

Treatment

There are three main treatment options available to treat soft tissue sarcoma in cats and dogs: surgery, radiation therapy, and

chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs (chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemotherap ...

. Surgery alone or in combination with radiation therapy are used to treat the tumor at its original location, and chemotherapy is usually used to prevent or at least slow down the process of

in pets diagnosed with tumor subtypes known to be highly aggressive.

References

{{Reflist

External links

''Soft Tissue Sarcoma in Cats and Dogs'' from Pet Cancer Centerand Prevention of Canine Cancer" from CanineCare.US
* ttp://veterinarycancer.com/softtissuesarcoma.html''Soft Tissue Sarcomas'' from Animal Cancer & Imaging Center Cancer in dogs Cancer in cats