Primary peritoneal cancer (PPC) grows out of the epithelial cells of the peritoneum. PPC is a rare type of cancer, usually associated with cancer of the ovary. They are both very similar, sometimes indistinguishable from one another, and treatment is the same for both types of cancer.
There are few known risks for this disease, although age and certain genetic mutations associated with breast and ovarian cancer are among them. These cancers tend to occur in older women and are extremely rare in men.
Symptoms are usually absent for a long time. When they do appear, they could include:
- Ascites – abdominal swelling due to fluid build-up.
- Unexpected weight gain.
- Abdominal pain.
- Frequent need to urinate.
These symptoms can be associated with many other conditions, but they call for further study. A specialist, usually a gynecologist, will order a series of tests, including a blood test called CA125, to check for elevated levels of this protein, which could indicate PPC or ovarian carcinoma. In addition, other tests used to determine the presence of cancer will be:
- Pelvic or vaginal ultrasound, which uses sound waves to develop a picture of the inside of the abdomen and can distinguish fluid and solid masses.
- CT scan, which uses X-rays to create a picture of the organs affected.
- MRI uses magnetic resonance to create an even more detailed picture of organs, structures, and tumours, if present.
- Paracentesis is the removal of fluid build-up in the abdomen (ascites) to extract cells that could indicate cancer is present.
- Laparoscopy and/or laparotomy are surgical procedures. Laparoscopy uses a probe that is inserted in the abdomen with a camera at one end, which allows for direct visualization of the insides and the opportunity to take a small sample or biopsy for testing. Laparotomy consists of a small incision on the abdominal wall to access the peritoneum and take a sample for pathological testing.
Treatment usually consists of surgery and chemotherapy, and involves removal of the uterus, ovaries, and omentum, which is the layer of fat that covers the organs. This is called debulking surgery. Chemotherapy can be used on its own or in combination with surgery to kill as many malignant cells as possible. In addition to intravenous administration of chemotherapy, the specialists might also decide on intraperitoneal chemotherapy, which administers the drugs directly into the abdomen.