Ovarian cancer staging involves determining the extent of a tumor. For ovarian cancer, this requires a thorough surgical procedure in which the uterus, ovaries, omentum (fat pad in the abdomen), lymph nodes, and all visible tumor is removed from the body.
Ovarian cancer surgery is almost exclusively performed using open surgery techniques, with a mid-line incision on the abdomen. Minimally invasive laparoscopic staging for ovarian cancer is not currently recommended.
Most ovarian cancers are found at advanced stages, when symptoms become more apparent. Only 25% of ovarian tumors are found at earlier stages; if ovarian cancer is found early, the chance of curing it increases dramatically. Patients with Stage I tumors have a 95% chance of long-term survival, while patients with Stage IV tumors have an average 5-year survival rate of 15-20%.
Ovarian cancer is staged as follows:
The tumor is found only within the ovary
Stage IA: The tumor is limited to one ovary
Stage IB: The tumor is present in both ovaries
Stage IC: The tumor is ruptured or cancer cells are found in the abdominal fluid
The cancer has spread to other parts of the pelvis.
Stage IIA: The tumor has spread to the uterus or fallopian tubes
Stage IIB: The tumor has spread to the bladder, rectum or colon
Stage IIC: The tumor has spread to any of the above and the abdominal fluid.
The cancer has spread to the upper abdomen or lymph nodes.
Stage IIIA: The tumor has spread to the lining of the abdomen but is microscopic.
Stage IIIB: The cancer has spread into the abdomen and is visible but ‹2 centimeters.
Stage IIIC: The cancer has spread into the abdomen and is larger than 2 centimeters or tumor is found within the lymph nodes.
The cancer has spread to the lung, liver or other distant organs.
Ovarian cancer recurs over 75% of the time in advanced stages despite additional therapy after surgery. Recurrent ovarian cancer is usually limited to the abdominal cavity, but can be found anywhere in the body. Treatment of recurrent ovarian cancer usually consists of chemotherapy but surgery may also be performed in select patients where it will be beneficial.
Ovarian cancers are classified as platinum sensitive or platinum resistant, based on response to initial chemotherapy. Tumors that recur within 6 months of stoppage of chemotherapy are considered platinum resistant while ones recurring after 6 months are platinum sensitive. This information will be used to determine further treatments.