Endometrioid tumor

Endometrioid tumor
Classification and external resources
ICD-O	8380-8381
MeSH	D018269

Endometrioid tumors are a class of tumor characterized by a resemblance to endometrium/^[1] endometrial carcinoma, and over a third of cases have focal squamous differentiation.

Ovary

Ovarian cancers in women aged 20+, with area representing relative incidence and color representing 5-year relative survival rate.^[2] Endometrioid tumor is labeled at bottom left.

They are part of the surface epithelial tumor group of ovarian neoplasms (10–20% of which are the endometrioid type). Benign and borderline variants are rare, as the majority are malignant. There is an association with endometriosis and concurrent primary endometrial carcinoma (endometrial cancer).

On gross pathological examination, the tumor is cystic and may be solid and some arise in cystic endometriosis. In 40% of cases, endometrioid tumors are found bilaterally.^[3]

Endometrium

Endometrioid carcinoma can also arise in the endometrium.^[4][5]

Grades 1 and 2 are considered "type 1" endometrial cancer, while grade 3 is considered "type 2".^[6]

Molecular biology

CTNNB1 and PTEN mutations

Ovarian and endometrial endometrioid carcinomas have distinct CTNNB1 and PTEN gene mutation profiles. PTEN mutations are more frequent in low-grade endometrial endometrioid carcinomas (67%) compared with low-grade ovarian endometrioid carcinomas (17%). By contrast, CTNNB1 mutations are significantly different in low-grade ovarian endometrioid carcinomas (53%) compared with low-grade endometrial endometrioid carcinomas (28%). This difference in CTNNB1 mutation frequency may be reflective of the distinct tumoral microenvironments; the epithelial cells lining an endometriotic cyst within the ovary are exposed to a highly oxidative environment that promotes tumorigenesis. ^[7]

References

1. "Dorlands Medical Dictionary:endometrioid tumor".
2. Kosary, Carol L. (2007). "Chapter 16: Cancers of the Ovary" (PDF). In Baguio, RNL; Young, JL; Keel, GE; Eisner, MP; Lin, YD; Horner, M-J. SEER Survival Monograph: Cancer Survival Among Adults: US SEER Program, 1988-2001, Patient and Tumor Characteristics. SEER Program. NIH Pub. No. 07-6215. Bethesda, MD: National Cancer Institute. pp. 133–144.
3. Robbins; Cotran, eds. (2005). Pathologic Basis of Disease (7th ed.). Philadelphia: Saunders. ISBN 0-7216-0187-1.
4. Mulvany NJ, Allen DG (January 2008). "Combined large cell neuroendocrine and endometrioid carcinoma of the endometrium". Int. J. Gynecol. Pathol. 27 (1): 49–57. doi:10.1097/pgp.0b013e31806219c5. PMID 18156975.
5. Carcinoma, Endometrioid at the US National Library of Medicine Medical Subject Headings (MeSH)
6. "ACS :: What Is Endometrial Cancer?". Retrieved 2010-03-24.
7. McConechy, M. K.; Ding, J; Senz, J; Yang, W; Melnyk, N; Tone, A. A.; Prentice, L. M.; Wiegand, K. C.; McAlpine, J. N.; Shah, S. P.; Lee, C. H.; Goodfellow, P. J.; Gilks, C. B.; Huntsman, D. G. (2014). "Ovarian and endometrial endometrioid carcinomas have distinct CTNNB1 and PTEN mutation profiles". Modern Pathology 27 (1): 128–34. doi:10.1038/modpathol.2013.107. PMC 3915240. PMID 23765252.