Peritoneal Cancer


What is peritoneal cancer?

Cancer that has spread to the lining surfaces of the peritoneal (abdominal) cavity from ovarian cancer, primary colorectal cancer, appendiceal cancer, or mesothelioma and pseudomyxoma peritonei—known as peritoneal carcinomatosis—are cancers that are frequently referred to as peritoneal cancers. Whether peritoneal cancer starts in the peritoneum or spreads from somewhere else (colon, appendix, ovary), it is considered advanced (stage IV) once it’s in the peritoneum and might be referred to as peritoneal carcinomatosis.

Who is at risk for peritoneal cancer?

It's not known exactly what causes peritoneal cancer, though the process begins when a series of mutations in peritoneal cells results in out-of-control growth. This could be related to a prior cancer that has now spread to the peritoneum or another cancer type known as a primary peritoneal cancer.


What are the symptoms?
  • Patients in the early stages of the disease will often have few symptoms until the disease is fairly advanced. When symptoms occur, they are often vague and nonspecific, with symptoms of abdominal swelling, diffuse abdominal pain, urinary frequency and a sense of fullness when eating. Other symptoms may include bowel changes (more frequent constipation), abnormal vaginal bleeding, an abdominal mass or unintended weight loss.
  • As the disease progresses, fluid may build up in the abdomen, causing abdominal discomfort, nausea and vomiting, and shortness of breath. Fatigue is also common.
  • Complications of peritoneal cancer may include bowel obstructions (sometimes necessitating a stoma, or hole between the intestine and the outside of the body), and urinary tract obstruction (due to blockage of the ureters by tumors), sometimes requiring a stent or nephrostomy tube (a tube from the kidney to the outside of the body).


How is it diagnosed?
  • Many different tests can be used to diagnose a patient with peritoneal carcinomatosis that started from another organ such as the appendix, colon, stomach, ovaries or cancers that originated in the peritoneum (primary peritoneal or mesothelioma).
  • Obtaining a history regarding your symptoms is frequently very helpful and this is followed by a physical exam. On physical examination, your surgeon can sometimes feel tumor nodules in the abdomen or fluid (ascites).
  • Checking your tumor markers, which are blood tests that may be elevated when patients have this type of cancer, can also be helpful.
  • Imaging studies are helpful in evaluating patients who have symptoms suggestive of peritoneal carcinomatosis. Patients have either a CT scan or MRI of the abdomen and pelvis to confirm the presence of new or recurrent disease in the peritoneum. These imaging studies are done to assess the extent of disease in the abdomen. PET-CT can also be done to determine if disease has spread outside the abdominal cavity, such as the lungs.
  • Laparoscopy is performed to confirm the diagnosis and determine if a patient is a candidate for cytoreductive surgery and HIPEC. Laparoscopy is a minimally invasive procedure where, through small incisions, samples of tumor (biopsies) are removed and sent to pathology to confirm a diagnosis. Fluid in the abdominal cavity also can be sampled to look for the presence of cancer cells. This procedure is also used to evaluate the extent of disease in the peritoneal cavity and to calculate the peritoneal carcinomatosis index (PCI) which is used to determine if a patient is a candidate for cytoreductive surgery and hyperthermic intraperitoneal chemoperfusion (HIPEC). PCI also correlates with a patient's prognosis.


How is it treated?
  • Depending on your tumor type, you may be a candidate for surgery to remove all of the tumor, known as cytoreduction, and followed by HIPEC. This technique, which combines surgery with chemotherapy, has revolutionized the treatment of cancers in the abdominal (peritoneal) lining that stem from colon, gastric, ovarian and appendiceal cancers, as well as mesothelioma and pseudomyxoma peritonei. HIPEC is essentially a chemotherapy "bath" that delivers heated chemotherapy directly into the abdominal cavity, where it penetrates the diseased tissue directly. This targeted contact of the heated drug kills the tumor nodules, which increases absorption of the chemotherapy solution. There is substantial clinical evidence that HIPEC is an effective treatment for patients with pseudomyxoma peritonei, mucinous adenocarcinoma of the appendix and peritoneal mesothelioma. Additionally, peritoneal metastases from colon cancer can be successfully treated in a significant number of patients.
  • There is a possibility that you may require intravenous or oral chemotherapy before or after your surgery based on your specific tumor type. This will be determined by your treatment team.
  • Additional therapies may also be utilized in the treatment of your specific tumor type. Targeted therapy may be used to treat some advanced primary peritoneal carcinoma. Sometimes a targeted therapy drug is combined with a chemotherapy drug. Hormonal therapy may be given in addition to chemotherapy to treat advanced primary peritoneal carcinoma. Lastly, radiation therapy is sometimes used to treat advanced primary or recurrent peritoneal carcinoma.

When should I call my provider?

You should call your healthcare provider if you have symptoms including unexplained weight loss, anorexia, abdominal pain, bloating, nausea or vomiting, or changes in bowel habits.

Key points about peritoneal cancer
  • Many of the cancers treated with HIPEC are diseases treated by multiple disciplines in medicine and surgery. It is important that a patient discusses HIPEC therapy with their oncologist and surgeon, who can guide their therapy appropriately.
  • HIPEC has several advantages over standard chemotherapy:
    • It is a single treatment done in the operating room, instead of multiple treatments over several weeks.
    • 90% of the drug stays within the abdominal cavity (directly to the cancer area), decreasing toxic effects on the rest of the body.
    • It allows for a more intense dose of chemotherapy.
  • If surgery is not an option, based on the characteristics of location of the tumors and the impossibility of removing all visible cancer, we will work with you to recommend other options—which may include targeted therapy or immune therapy to personalize your cancer treatment.

Next steps:

Items that we may need for your office visit include:

  • Recent radiology films and reports (CT, PET, MRI) of abdomen, pelvis and chest
  • Pathology report
  • Tumor markers: CEA, CA 19-9, CA 125
  • Operative notes from all prior surgeries related to this disease
  • Summary of all chemotherapy treatment regimens

Tips to get the most out of your visit with a surgeon:
  • Write down all your questions before you visit.
  • You will be provided information regarding your diagnosis, surgery, risks and complications of surgery as well as prognosis, and it is important that you bring someone with you to help you remember all the information provided to you.
  • Ask if there are other options for treatment.
  • Ask about all the tests and procedures that need to be performed to confirm your diagnosis.
  • Know what your prognosis is if you do the procedure, and if you also decide not to proceed with treatment.
  • Write down what you must do to prepare for any tests or surgery.
  • Know how to contact your provider if you have any further questions.

© 2000-2022 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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