Primary peritoneal cancer is a rare form of cancer originating in the epithelial cells lining the peritoneum, a layer of tissue inside the abdomen designed to provide protection and support to the abdominal organs. This cancer is treatable and the prognosis varies, depending on the stage of the cancer when it is identified. Unfortunately, primary peritoneal cancer is often identified at a late stage as a result of vague symptoms; patients may not immediately seek treatment and it can take time to trace the cause of the symptoms.
This cancer most commonly develops around the pelvis and it is closely associated with ovarian cancer. Ovarian cancer often spreads to the peritoneum and primary peritoneal cancer can also spread to the ovaries, as the same kinds of epithelial cells are involved. Because of the ovarian cancer link, it is important to screen patients with peritoneal cancers for ovarian cancers, to see where the cancer originated and to check for signs of metastases.
Men very rarely develop this cancer. In women, the causes are unclear but the incidence is much higher in women with mutations in the BRCA gene, the gene linked with breast and ovarian cancer. Women with variant or mutated BRCA genes should make sure they are screened regularly for breast and ovarian cancer to catch such cancers early if they develop. Prophylactic treatments may also be considered in some cases, if a patient is at especially high risk.
Symptoms of primary peritoneal cancer include weight gain, swelling in the abdomen, nausea, loss of appetite, lethargy, stomach pain, and changes in toilet habits, such as loose stool or the development of discoloration in the urine. Screening for this cancer can include physical examinations, medical imaging studies, and biopsies. During the process of diagnosis, the cancer will also be staged, determining how aggressive it is and how far it has spread.
Available treatments for primary peritoneal cancer include surgery to excise tumors, radiation therapy to kill cancer cells, and chemotherapy using medications to target and destroy cancer cells. Treatment recommendations will vary depending on the stage of the cancer, the patient's age, and conversations between patient and oncologist. When reviewing treatment options, it can be helpful to ask about prognoses with different treatments and to explore clinical trial options. Clinical trials can provide access to new treatments in addition to providing valuable data for cancer diagnosis and treatment that will benefit future generations of patients.