If you’re asking this question, chances are you or someone you care about has been diagnosed with cancer.
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Hearing that you have cancer is overwhelming and stressful. The complex medical terms we use to describe what’s happening can add confusion to the mix.
Two different forms of cancer
It helps to understand that carcinomas and sarcomas are two different types of cancer, says Dale Shepard, MD, PhD.
“Carcinomas are the most common type of cancer and are the ones most people would immediately think of,” he says. “By comparison, sarcomas are rare, and most people don’t know what they are and can’t recall anyone who has had one.”
Where carcinomas develop
Carcinomas start in epithelial cells. These are the cells that line the surfaces inside and outside your body:
- Adenocarcinomas start in tissues that secrete fluids or mucus, for example, in the breast, colon, lung and prostate.
- Basal cell carcinomas develop at the base of the skin’s outer layer.
- Squamous cell carcinomas form just below the surface of the skin’s outer layer.
- Transitional cell carcinomas start in tissues lining the bladder, ureters, kidneys or other organs.
Where sarcomas develop
Sarcomas start in mesenchymal cells. These are the cells that make your bones and soft tissues. There are two main types and more than 50 subtypes of sarcoma:
- Osteosarcomas start in the bone, cartilage or bone marrow.
- Soft-tissue sarcomas can begin in the fat (liposarcoma), muscle (rhabdomyosarcoma or leiomyosarcoma), nerves (peripheral nerve sheath tumors), fibrous tissue (fibrosarcoma), blood or lymph vessels (angiosarcoma) or deep skin tissues (epithelioid sarcoma).
Remember: All ‘omas’ aren’t cancer
In cancers, including carcinoma and sarcoma, cells divide uncontrollably, invade nearby tissues and can eventually spread to distant sites.
“It is important to know that benign masses may also end in ‘oma,’ which means ‘tumor,’ but these cells behave — and are treated — quite differently,” says Dr. Shepard.
“For example, cells in benign tumors such as adenomas, fibromas and angiomas will not invade nearby tissues or spread to other sites.”
Thus, the tumors don’t have the same negative consequences as a carcinoma or sarcoma.
We’re here to help
Whenever you’re worried that you don’t have all the information you need about a cancer diagnosis, “don’t hesitate to reach out and ask for help,” says Dr. Shepard.
That’s why your doctors and caregiver team are here.