carcinosarcoma
Meaning of carcinosarcoma: One tumor wearing two faces, and the evidence now says both faces grew from a single ancestor cell rather than two cancers colliding.
Definition of carcinosarcoma
Carcinosarcoma is a rare aggressive tumor that contains two distinct malignant components: one that looks like a carcinoma, arising from lining or glandular tissue, and one that looks like a sarcoma, resembling bone, cartilage, muscle or other connective tissue. It occurs most often in the uterus, and also in the lung, esophagus, bladder and breast.
How carcinosarcoma is built
- carcin/o Combining form · Greek cancer, carcinoma
- sarc/o Combining form · Greek flesh, connective tissue
- -oma Suffix · Greek tumour, mass, swelling
A medical term is read from its ending backwards: the suffix first, then the prefix, then the root. See all 223 word parts.
How can one tumor be two cancers?
The obvious explanation, that two separate cancers happened to arise side by side, turned out to be wrong for almost every case examined. Genetic studies show the two components share the same mutations, which means both descend from a single ancestor cell. What happened is that some of that cell's descendants lost their epithelial character and took on the appearance and behavior of connective tissue. The tumor is therefore best understood as a carcinoma that has changed its appearance, not as a mixture of two diseases, and the older name mixed mullerian tumor reflects the earlier view.
Where does it arise?
| Site | Notes |
|---|---|
| Uterus | Commonest site; behaves like a high grade endometrial cancer |
| Ovary and fallopian tube | Uncommon, aggressive |
| Lung | Rare; often called pulmonary blastoma when immature elements dominate |
| Esophagus | Tends to grow into the lumen as a polyp |
| Bladder and breast | Rare; the breast form is usually classed as metaplastic carcinoma |
Why does the classification matter?
For years the uterine form was grouped with sarcomas and treated with sarcoma drug regimens. Recognizing that its malignant behavior is driven by the carcinoma component moved it into the group treated as a high grade carcinoma of the uterine lining, which changed which drugs are considered first. Naming is not a labeling exercise here; it decides the treatment pathway.
How does it behave?
Worse than either component alone would suggest. It spreads early, both through lymph channels and directly into surrounding tissue, and it frequently recurs after surgery even when the tumor appeared confined. The sarcoma-like component is more likely to be found in the deposits that spread. Age at presentation is typically later than for the ordinary carcinoma of the same organ, and prior radiation to the pelvis is one of the few recognized risk factors for the uterine form.
Also known as
Used in a sentence
Histology showed a uterine carcinosarcoma with heterologous cartilage elements.
Good to know
Both components share the same mutations, so a carcinosarcoma is a single cancer whose cells have changed appearance rather than two tumors that arose together, and the carcinoma component drives its behavior.
Word origin
Where “carcinosarcoma” comes from
Built from the Greek karkinos, meaning crab and used for cancer, with sarx, meaning flesh, and the tumor ending -oma.