Uterine Cancer Types

The term endometrial cancer is used to describe a cancerous tumor that originates from the endometrial lining of the uterus. The type of cell from which the tumor develops determines the type of uterine cancer. Around 90 percent of all uterine cancers are endometrial adenocarcinomas.

Uterine Anatomy

The lining of the uterus, known as the endometrium, is composed of tall, column-shaped epithelial cells. “Pits ” in the lining connect the tissue ‘s surface to the uterine glands. The epithelial cells, pits, connective tissue and blood vessels are all part of the endometrium.

Uterine Adenocarcinoma

The Uterus Adenocarcinomas are cancers that originate in the cells of the surface layer of the uterus (endometrium), a tissue made up of secretory glands.

Adenocarcinomas are divided into three sub-types: Grades I, II and III. The three adenocarcinoma sub-types are categorized according to the composition and grade of the tumor. Grade I tumors are the lowest grade, and are made up of cells with some resemblance to normal tissue, whereas Grade III tumors are more irregular, consisting of a greater number of abnormal-looking cancer cells.

Uterine Sarcoma

If the tumor develops from the deeper, muscular walls of the uterus, it is known as uterine sarcoma. Although as few as five percent of uterine cancers are sarcomas, they are, nevertheless, an aggressive type of uterine cancer. Sarcomas are divided into three categories, depending on the original cell type:

  • Endometrial stromal sarcomas originate in the structural “nurse ” cells, called stromal cells, that support the uterus.
  • Uterine leiomyosarcomas are derived from smooth uterine muscle cells.
  • Uterine carcinosarcomas are “mixed ” endometrial tumors that arise in the endometrium and possess both sarcoma and carcinoma type characteristics.

Rare Types of Endometrial Cancer:

Certain types of endometrial cancers develop from rare cell types and are typically associated with older age groups. In these cases the cancer has often metastasized from the uterus to other parts of the body and the prognosis is poor. Rare types of endometrial cancer include:

  • papillary serous carcinoma
  • endometrial clear cell carcinoma
  • papillary endometrial carcinoma
  • endometrial mucinous carcinoma.