Risk Management & Treatment

Stages and subtypes of fallopian tube, ovarian and primary peritoneal cancer

Ovarian, fallopian tube, and primary peritoneal cancer are very closely related. Although they each begin in different parts of the reproductive tract, the cells look and behave the same and similar treatments are used for each. Primary peritoneal cancer arises from the lining of the abdomen, also known as the peritoneum.


After surgery confirms ovarian, fallopian tube or primary peritoneal cancer, the pathologist looks closely at the type of cells found in the tumor for additional clues on how to best treat it. The subtypes can also be classified as high-grade or low-grade depending on how quickly the cancer cells are growing and dividing and the presence of certain genetic mutations within the tumor. The subtype and grade affect treatment options and prognosis. The most common subtypes of ovarian cancer belong to a group called epithelial cancers, that arise from the outer lining of the ovaries and tubes. These include:

  • Serous 
  • Endometrioid
  • Clear cell
  • Mucinous

High-grade serous are the most common type of ovarian cancer. The following rare subtypes arise from other cells within the ovaries and tubes:

  • Stromal cell 
  • Germ cell
  • Small cell
  • Mixed Mullerian (cancinosarcoma)

Certain subtypes have been linked to specific inherited mutations. Women with Lynch syndrome may develop any of the epithelial subtypes listed above. Women with a BRCA1 or BRCA2 mutation are most likely to develop high-grade serous subtype (although they may develop any subtype).

Stages of cancer

The stage of a cancer refers to whether it has spread beyond the ovaries or tubes, and if it has, the location in the body where it has spread. Measuring the stage of ovarian cancer helps doctors decide how to treat it. 

The stages of ovarian and fallopian tube cancers are:

  • Stage 1 is confined to the ovary or fallopian tube
  • Stage 2 is confined to the pelvis
  • Stageis confined to the upper abdomen
  • Stage 4 has spread beyond the abdomen

Stages 3 and 4 are considered advanced ovarian cancer. 

National guidelines recommend that women with certain inherited mutations linked to ovarian cancer undergo surgery to remove their ovaries and fallopian tubes to lower their risk for cancer. In some of these women, a fallopian tube pre-cancerous stage, known as serous tubal intraepithelial carcinoma (STIC), may be found. Researchers are studying how to best treat STIC lesions.

Doctors may order additional tumor tests to help guide treatment. For some people with advanced cancers, tumor biomarker testing can look for further clues to help guide the choice of targeted therapies. 


If you are a person who has been diagnosed with fallopian tube, ovarian or primary peritoneal cancer, you can find peer support through the following resources:

Other organizations that provide support for people diagnosed with ovarian cancer include:

  • The National Ovarian Cancer Coalition is a national nonprofit support organization for women diagnosed with ovarian cancer. 
  • The Ovarian Cancer Research Alliance is a national nonprofit organization with information and support resources for women affected by ovarian cancer. 
  • SHARE is a nonprofit that provides support and information for women with breast, ovarian or endometrial cancer.  
  • Sharsheret is a national organization for the Jewish breast and ovarian cancer community.  
  • Steps Through OC is a support program of the Clearity Foundation.