Malignant mesothelioma is a rare, asbestos-related cancer. Only about 3,000 cases arise in the United States each year. Most of these cases affect the lining of the lungs, which is called the pleura. However, a small portion of mesothelioma cases occur in the lining of the abdomen (the peritoneum).
With only a few hundred cases of peritoneal mesothelioma yearly, the pace of research can seem slow. Researchers have used insights from other abdominal cancers to help overcome this challenge. This approach has proven successful.
Peritoneal mesothelioma treated with cytoreductive surgery (CRS) and heated, local chemotherapy (HIPEC) has a median survival ranging from two to more than 5.5 years. And, according to newer research, patients may survive even longer if they undergo repeat CRS and/or HIPEC.
CRS and HIPEC Target Mesothelioma on Two Levels
The combination of CRS and HIPEC fights peritoneal mesothelioma in two different ways. In CRS, a surgeon physically removes as much tumor tissue as possible. But, a surgeon’s eyes cannot see the tiny, single cancer cells left behind by surgery. If these cells are not removed, they may go on to form new tumors in the abdomen or elsewhere in the body. This is where HIPEC helps.
HIPEC for peritoneal mesothelioma often uses a chemotherapy drug called cisplatin. Cisplatin sticks to structures inside cells, interfering with cells’ ability to grow and divide. This eventually kills cells that encounter cisplatin. Cisplatin may be combined with other chemotherapy drugs to improve efficacy.
In a HIPEC procedure, chemotherapy drugs such as cisplatin are heated and applied to the abdomen, usually after CRS. This allows the chemotherapy to wash over any tumor cells left behind during CRS. When this procedure was developed, researchers believed adding HIPEC to CRS would extend survival.
It would seem these innovators were correct in that belief. One early study of CRS followed by HIPEC in peritoneal mesothelioma achieved a median survival of almost three years.
Study Shows Repeating CRS and/or HIPEC May Further Improve Survival
In the last decade, doctors have found at least one way to improve upon the CRS and HIPEC procedure. Studies have reported improved survival in patients treated with more than one round of CRS and HIPEC.
Researchers at the Moffitt Cancer Center performed one of these studies. From June 2004 to March 2012, Moffitt Cancer Center doctors treated 29 peritoneal mesothelioma patients with CRS. Of these patients, 26 also received at least one round of HIPEC. 14 of the 26 HIPEC patients also received systemic chemotherapy after CRS and HIPEC.
The 26 patients who received CRS and HIPEC also underwent a variety of additional treatments, including:
- Early postoperative chemotherapy (EPIC): EPIC is like HIPEC except the chemotherapy in EPIC is not heated. Twenty patients underwent EPIC treatment after HIPEC.
- Second-round CRS + HIPEC: Eight patients received a second round of CRS + HIPEC.
- Second-round EPIC: Seven patients received EPIC treatment after their second round of CRS + HIPEC.
- Third-round CRS + HIPEC + EPIC: Two patients received a third round of CRS + HIPEC.
- Fourth- and fifth-round CRS + HIPEC + EPIC: One patient received a total of five rounds of CRS + HIPEC + EPIC treatment.
Patients undergoing multiple rounds of treatment had a median survival of 80 months. Those undergoing only a single round of CRS and HIPEC had a median survival of 27.2 months.
HIPEC Surgeon: Repeat CRS and HIPEC May Help Select Patients
Given the encouraging results above, most patients would likely choose repeat CRS and HIPEC treatment if given the choice. According to experts, it may not be that simple.
Dr. Sabha Ganai is an Associate Professor of Surgery at the University of North Dakota and a clinical researcher. She specializes in the treatment of peritoneal surface cancers, including mesothelioma. According to Dr. Ganai, the decision to pursue repeat CRS and/or HIPEC involves a number of factors, including:
- Extent of existing cancer at the time of repeat treatment
- Success of the original CRS procedure
- Other conditions the patient may have
- Tumor characteristics and biology
Because new treatments, including immunotherapy, are in development, Dr. Ganai emphasized the need for a multidisciplinary decision about repeat treatment.
“In properly selected patients who have disease that can be optimally debulked, this strategy can be worthwhile and potentially lead to long term cures.”
– Dr. Sabha Ganai, Peritoneal Surface Cancer Specialist
Repeat Treatment in Regular Practice Is Rare but Useful
We asked Dr. Ganai about her personal experience with repeat CRS and/or HIPEC procedures. She said repeat CRS and HIPEC are a small but not uncommon part of her practice. Dr. Ganai uses such procedures strategically to “clear recurrent disease and maintain quality of life.”
Who Should Undergo Repeat CRS and HIPEC Treatment?
According to Dr. Ganai, select peritoneal mesothelioma patients may benefit from repeat CRS and HIPEC. Patients in the Moffitt Cancer Center study experienced prolonged survival with this multimodal treatment approach.
However, this treatment may not be appropriate for every patient. As such, it is important that patients seek the advice of a mesothelioma expert, such as Dr. Ganai.
