What Does Peritoneal Nodule Mean?

NCI defines the peritoneum as the tissue that lines the abdominal wall and covers most of the organs in the abdomen.

A peritoneal nodule is a small spot or lump on that lining, seen on a scan or during surgery. Reports may also use words like "peritoneal deposits," "implants," "thickening," "omental caking" or "peritoneal carcinomatosis."

A nodule is a description, not a diagnosis. In someone with a known cancer, the radiologist flags it because it may matter for staging. Your care team reads it with the rest of your report, history and tests.

NCI describes peritoneal carcinomatosis as a serious condition. Cancer spreads and forms tumors on the peritoneum. It can happen with many cancers. NCI says it is most common with cancers of the ovary, colon, rectum, stomach, pancreas or appendix.

Ascites means a buildup of fluid in the abdomen. NCI notes that in late-stage cancer, tumor cells may be found in that fluid.

The fluid can be drained with a thin needle or tube. This is called a paracentesis. MedlinePlus says the fluid is tested to look for the cause. Removing a large amount can also make you more comfortable. Ask your team what a result would and would not rule out.

If ovarian cancer is suspected, a CA-125 blood test may be done. NCI says a raised CA-125 can be a sign of cancer or of another condition, such as endometriosis.

Some people with cancer on the peritoneum are offered surgery to remove as much tumor as possible. NCI describes HIPEC, where a heated drug solution is put into the abdomen during that surgery to kill remaining tumor cells. Ask whether this is an option for you. Ask your surgeon to explain how they measure the amount of disease, and what the risks are for you.

• How many nodules, how large, and where?
• Is this a new finding, or was it on my last scan?
• Do we have tissue or fluid confirming what it is?
• If a fluid test was negative, what does that change?
• Am I a candidate for surgery, and how much disease do you think there is?
• Which center near me does this operation often?

• Your belly is hard or very tender, or you have severe belly pain.
• You have belly pain with vomiting and cannot pass gas or stool.
• You are short of breath, or cannot lie flat.
• You have a fever of 100.4°F (38°C) or higher, especially during chemotherapy. CDC calls fever during chemotherapy a medical emergency and says to call your doctor right away.
• You have fever or new drainage after a recent abdominal procedure.

Call your care team right away for belly swelling that keeps growing over days, even without those signs.

What Does Ascites Mean on a Scan?, What Does Omental Caking Mean?, Ovarian Cancer, and What Metastatic Cancer Means.

• NCI Dictionary of Cancer Terms — peritoneum
• NCI Dictionary of Cancer Terms — peritoneal carcinomatosis
• NCI Dictionary of Cancer Terms — ascites
• MedlinePlus — Ascites
• MedlinePlus — Intestinal obstruction
• NCI PDQ — Ovarian Epithelial, Fallopian Tube, and Primary Peritoneal Cancer Treatment (Patient Version)
• CDC — Fever during chemotherapy