Peritoneal Cancer Diagnosis and Staging
People usually don’t experience symptoms in the early stages of peritoneal cancer. When symptoms do occur, they often resemble those of other, less serious conditions such as heartburn or indigestion. It’s important to see experienced specialists with expertise in evaluating symptoms to confirm an accurate diagnosis.
Diagnosing Peritoneal Cancer
At UT Southwestern Medical Center, our cancer specialists use the most advanced techniques to diagnose peritoneal cancer. Our physicians begin with a thorough evaluation that includes a:
- Discussion of symptoms
- Review of personal and family medical history
- Physical exam, often with a pelvic exam to check the uterus, vagina, ovaries, fallopian tubes, bladder, and rectum for abnormalities
We sometimes diagnose peritoneal cancer differently, depending on where it began:
- Primary peritoneal cancer: This is cancer that begins in the peritoneum, and we often find this type during abdominal surgery for other reasons.
- Secondary peritoneal cancer: Cancer can begin in other abdominal organs, such as the appendix, intestines, or ovaries, and spread (metastasize) to the peritoneum. We use a variety of imaging tests or procedures to help diagnose secondary peritoneal cancer.
Tests for Peritoneal Cancer
Tests and procedures that we often use include:
- Computed tomography (CT) scans: Specialized X-ray technology creates cross-sectional images inside the abdomen. CT scans show details of the peritoneum and organs to assess for abnormalities.
- Magnetic resonance imaging (MRI) scans: Equipment that uses a powerful magnet and radio waves can produce images that show the extent of diseased tissue in the abdomen.
- Ultrasound: This imaging uses high-frequency sound waves to create images of abdominal organs. Ultrasound can show differences between healthy tissues and cancerous tumors.
- Blood tests: Certain tests can show increased levels of tumor markers such as CA125, CA 19-9, CEA, or HE4, which can indicate peritoneal cancer. However, these tumor marker levels can be high for other reasons.
- Laparoscopy: This is a minimally invasive surgical procedure in which our surgeons create tiny incisions to insert narrow scopes with lens to view the peritoneum (inside of the abdomen). If we spot any fluid or abnormal tissue, we can take a tiny sample (biopsy) of the tissue or fluid to evaluate under a microscope for signs of cancer. The surgeon might also determine the peritoneal cancer index (PCI) to assess the extent of peritoneal cancer in the abdominal cavity during this procedure.
Staging Peritoneal Cancer
After we establish a diagnosis of peritoneal cancer, we stage the cancer based on its size, location, and origin, if it has spread from another organ. Because peritoneal cancer usually doesn’t produce symptoms in its early stages, patients are often diagnosed with stage 3 or 4 cancer by the time it’s found.
Stages of Primary Peritoneal Cancer
Stage 3 of primary peritoneal cancer includes three substages:
- 3A: The cancer has spread to lymph nodes outside the peritoneum, or cancer cells have spread to the surface of the peritoneum, outside the pelvis.
- 3B: The cancer has spread to the peritoneum outside the pelvis. The cancer in the peritoneum is 2 cm or smaller. It might have also spread to lymph nodes outside the peritoneum.
- 3C: The cancer has spread to the peritoneum outside the pelvis, and the cancer in the peritoneum is larger than 2 cm. It might have spread to lymph nodes outside the peritoneum or to the surface of the liver or spleen.
In stage 4, cancer has spread to other organs and has two substages:
- 4A: Cancer cells are found in the fluid that builds up around the lungs.
- 4B: The cancer has spread to organs and tissues outside the abdomen, such as the liver, lungs, or lymph nodes in the groin.
Staging Secondary Peritoneal Cancer
Our cancer specialists stage secondary peritoneal cancer based on the primary cancer. Primary cancer that spreads to the peritoneum from elsewhere in the body is usually considered stage 4.