Peritoneal cancer – Stage 4

What is peritoneal cancer?

Peritoneal cancer means the presence of cancer cells on the peritoneum.  The tumor deposits are usually small , the size of rice grains. At times the deposits can be large even upto 5 cm in size.

Peritoneal cancer is primary when the tumro arises from the peritoneum itself (primary peritoneal carcinomatoses). It is secondary when tumor from other sites spreads to the peritoneum. Secondary spread is more commonAlmost any cancer can spread to the peritoneum, but this is more commonly seen in tumors of the abdominal cavity like such as tumors of the stomach, pancreas, large bowel (colon) and tumors of the ovaries and uterus.

What are the most frequent causes of Peritoneal Cancer Spread?

The cancers in which there is a high incidence of peritoneal deposits are colorectal cancer, ovarian cancer, gastric cancer, biliary tract cancers, pancreatic cancer and breast cancer.

When cancer has spread to the peritoneum is it the last stage/stage 4?

Yes spread of cancer to the peritoneum is considered stage 4 in most cancers. In ovarian cancer it is stage 3

Can stage 4 cancer be treated?

All stage 4 cancers are not the same. The outcome depends on the extent of tumor spread. Patients in whom the cancer is spread to only one organ, eg.  the liver in colorectal cancer or the peritoneum in ovarian cancer do better than patients in whom more than one organ is involved

Patients with peritoneal implants (tumor deposits) often have cancer  spread to  the liver or lungs. In some patients however, seeding is limited to the peritoneum. It is for this subgroup of patients that surgical treatment with cytoreductive surgery and HIPEC  may be possible.

With this kind of treatment, some patients can have a prolonged life and perform all the activities that people without cancer do.

In a patient with peritoneal cancer, the treatment and outcome depends on

  1. Primary tumor site: patients with colorectal, appendicular, ovarian cancer have a better outcome than other cancers
  2. Extent of metastatic spread: when multiple organs have tumor deposits, cure is usually not possible. Patients with disease limited to the peritoneum can be treated aggressively with a greater chance of cure.
  3. Extent of peritoneal spread: see the section on cytoreductive surgery and HIPEC