Soft tissue sarcoma and tumors arising from the mesodermal tissue that form connective tissue, blood and smooth muscles are often termed as spindle cell sarcomas.
During cell division, a special structure is built to facilitate the movement of chromosomes. This structure is called a spindle cell. It is a narrow, elongated cell that exists only till the time the cell division is taking place. The role of the spindle cells is complete once the cell division is complete. Spindle cell is characteristic of some forms of cancer.
Millions of cells in the body die every second. This is essential for cellular replacement.
Apoptosis is a process of the necessary death of cells. When the genetic structure of cells is altered, the cell dies its natural and necessary death. If this fails to happen, the mutated cell divides into mutated daughter cells and the process continues to form a tumor of abnormal cells that serve no purpose.
Spindle cell cancer in dogs is a family of tumors derived from connective tissue. This may develop in any part of the body. Connective tissue supports organs and fills spaces between the organs, forming tendons and ligaments. The tumors that are formed are mostly solitary and exist mainly in the subcutaneous tissues. Although high grade tumors are known to metastasize, these cancerous cells are mostly locally invasive and remain in the same place for a long period. Most of the tumors are solid, but some may occasionally have fluid in them.
Diagnosis of spindle cancer proceeds just like any other tumor in dog cancer. Initially, a fine needle aspirate is obtained from the tumor for laboratory testing along with X-rays. If a draining lymph node is indicated, an aspirate of that is obtained for histological examination. Similar to malignant melanoma in dogs, spindle cell sarcomas tend not to grow well, and an aspirate may not provide a definite confirmation. If spindle shaped cells are observed in microscopic examination, an incision may have to be made to obtain tissue mass for biopsy.
Considering that these tumors are mostly locally invasive, surgery is the preferred treatment. A margin of up to 3 cm around the tumor has to be obtained, keeping in mind the ability to sew up the wound after surgery. Considering the location and size of the tumor, the surgeon may have to exercise discretion about how best to excise.
Inability to totally excise the tumor may require adjuvant radiation therapy to avoid local recurrence. High grade tumors may not be possible to excise if metastasis has already occurred. In such instances, chemotherapy may be the only option left. Prognosis of spindle cell sarcoma depends largely upon the grade of the tumor and how efficiently local control is obtained.