What is peritoneal malignancy?

All cancers have the ability to spread to other places within the body.  This is called metastasis.  Certain cancers including appendiceal tumors, colorectal and other gastrointestinal cancers, ovarian cancer and others, may spread to the lining of the abdominal cavity in their later stages—this is peritoneal malignancy or peritoneal metastasis.  The peritoneum is the lining of the abdominal cavity. The tumor deposits can vary in size and number and can involve the peritoneum or grow on the surface of an organ (liver, spleen, stomach, small bowel, colon).  Unfortunately, IV chemotherapy is not very effective for these tumors. One way of treating peritoneal malignancy or peritoneal metastases is to perform a cytoreduction with or without HIPEC (heated intraperitoneal chemotherapy).

What is cytoreduction?

Cytoreduction refers to the process by which we remove as much of the tumor or tumors as possible.  This is a surgical procedure that can involve removing the lining of the peritoneum or specific organs. The process is described in more detail below.

What is HIPEC?

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a procedure in which heated chemotherapy is pumped directly into the abdominal (peritoneal) cavity. This procedure is only carried out if a complete cytoreduction is possible. HIPEC allows for much larger doses of highly concentrated chemotherapy; heating the chemotherapy helps the drug work even better.  This kills the smaller deposits that can’t be seen in the operating room.  Ultimately, HIPEC can improve some patients’ quality of life and extend their life expectancy. This process is also discussed in more detail below.

Determining good candidates for cytoreduction and HIPEC

At Siteman, we treat a number of cancer types with cytoreduction and HIPEC, including: colon, appendiceal, ovarian, mesothelioma, and certain pediatric cancers. We most commonly perform this procedure on patients who have metastastic colon cancer or appendiceal malignancies.

When patients are evaluated to determine if they are good candidates for cytoreduction and HIPEC, we use a variety of criteria including general health of the patient as well as the type of cancer and the amount of disease present.  We determine the amount of disease present using imaging, blood tests and sometimes we need to look in the abdomen with a scope (diagnostic laparoscopy).  Imaging is most often CT or MRI.  However, sometimes the small tumors that form on the surface are difficult to see with these images.  Because of this we sometimes we need to look in the abdomen with a scope. This is called a diagnostic laparoscopy.

Ultimately, our goal is to determine whether we think we can get rid of all the tumor through the process called cytoreduction.

The cytoreduction process

The purpose of cytoreductive surgery is to remove as much of the tumor or tumors as possible. The process can take 6-10 hours and the end goal is to remove all visible tumor.  A complete cytoreduction means that only tumors < 0.25 cm remain.  This is approximately the size of pencil eraser.  During this process, we often remove portions of the lining of the abdominal wall or peritoneum where these tumors tend to grow.  Other organs may also need to be removed, including the omentum (fatty apron covering the abdomen), small or large bowel, appendix,  spleen, gallbladder, and tubes and ovaries. Small or large bowel may require removal depending on involvement from tumor. In most cases, the ends of the bowel are re-connected before the end of the surgery (bowel anastomosis). In some cases, an ostomy may be needed. This may be temporary or permanent.

Imaging done in advance often determines if additional resection is required, but plans may change based on findings at the time of surgery.

After this procedure is complete, we perform the HIPEC portion of the procedure.

How does HIPEC work?

We insert tubing into the patient’s abdomen and perform a temporary closure.  The tubing (inflow and outflow) is connected to a heated pump. This machine circulates heated chemotherapy at a temperature of 42 degrees C.  The entire process lasts 60-90 minutes, after which the tubing is removed and the patient’s abdomen is flushed out with a large volume of water or saline.  The abdomen is carefully inspected and then re-closed with sutures or staples.

Recovery following HIPEC surgery

Immediately following the cytoreductive and HIPEC procedures, the patient will be taken to the ICU and remain there for 1-2 days mostly for careful monitoring of vital signs and urine output. The large majority of patients are extubated immediately after surgery and are able to breathe on their own.  Rarely, patients may require prolonged ventilation support: they are kept asleep using medications until they are ready to have the breathing tube removed (extubation).

Possible complications following surgery include impaired kidney function (kidney function labs and urine output will be closely monitored), temporary drop in blood cell counts, and ileus. The gut may be slow to return to normal functioning and getting back to a normal diet may be difficult, but patients will typically be able to return to a normal diet in time.

Generally, patients are in the hospital for about 5-7 days.  Most patients are discharged to home, but patients with other medical problems, advanced age, or who develop complications may require a short stay in a rehabilitation facility.

While patients may be back to doing some of their normal activities within the first few weeks after surgery and return to work in 6-12 weeks, the entire recovery process can take 6-9 months.

Prognosis after HIPEC surgery

The prognosis after HIPEC surgery heavily depends on the type of cancer the patient has, how advanced the cancer is, as well as the patient’s overall health. After surgery, we will follow closely with CT scans and blood tests to monitor for recurrence and to allow for early treatment.