The incidence of colorectal cancer (CRC) is more than 900,000 worldwide each year and nearly 500,000 patients die as a result of CRC (Parkin 2001). In patients with CRC, peritoneal carcinomatosis (PC) is the second‐most common cause of death (Ries 2006).

In literature three main routes of dissemination have been described. First, lymphatic dissemination in which tumor emboli move through lymphatic channels to progress within the lymph nodes. Second, the haematogenous route where tumor emboli move through the venules and capillaries and move along the portal blood system. These emboli can deposit in the liver and may progress into liver metastases, which are the most frequent metastases in patient with CRC. Third, tumor cells can gain access into the peritoneal cavity. This may be a result of full‐thickness invasion of the bowel wall by an invasive cancer or tumor spill during surgery due to trauma, blood loss or by lymphatic vessel transsection (Glehen 2003; Willett 1984; Schott 1998). It is hypothesized that, after surgery, tumor cells are trapped in fibrin clots that place them beyond the reach of the immunologic defences in the abdominal cavity, which may be the origin of PC (Sugarbaker 1994).

There are different options in the management of PC for CRC:

1. Palliative treatment:

Palliative systemic chemotherapy and supportive care are the standard therapies of these patients. Four clinical studies have been published, evaluating the efficacy of standard treatment in patients with PC of CRC origin, in which 5‐fluorouracil was the most used chemotherapeutic agent. They reported that patients treated with palliative treatment have a median survival between 5.4 and 12.6 months (Sadeghi 2000; Chu 1989; Jayne 2002; Bloemendaal 2005). Surgery is only used for palliative goals in order to increase quality of life. 

2. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

Recent publications suggest that a selected group of patients suffering from peritoneal carcinomatosis may benefit from an aggressive surgical approach including cytoreductive surgery and HIPEC (Sadeghi 2000; Jayne 2002; Ceelen 2008; Schneebaum 1996; Shen 2003; Elias 2004; Witkamp 2001).

In cytoreductive surgery (sometimes including peritonectomy) an attempt is made to remove all macroscopic tumours in the peritoneal cavity.

Cytoreductive surgery may include the following procedures:

Resections of viscera which may include rectum resection, small bowel resections, partial or total colectomy, cholecystectomy, partial gastrectomy and splenectomy.

Stripping of the peritoneum according to the Sugarbaker method which can include: right hemidiaphragm, left hemidiaphragm, omental bursa, greater omentum, lesser omentum, Glisson’s capsule, left colonic gutter, right colonic gutter, Douglas pouch and mesenteric peritoneum (Sugarbaker 1995).

Omentectomy.

Before starting the procedure, the presence and extent of macroscopic tumor deposits is recorded in all abdominal regions using a scoring system.

As an adjuvant to cytoreductive surgery, the abdominal cavity is perfused for 60‐120 minutes with HIPEC. Perfusion is performed using different techniques such as an open perfusion technique (Colosseum technique) or after closure of the abdomen. Using the Colosseum technique, bowel anastomoses and abdominal wall closure are performed after HIPEC, whereas in the closed technique all anastomosis are constructed and the abdomen closed before starting HIPEC.   

The procedures are long lasting and have a considerable mortality and morbidity. Total operation time can be up to 10 hours or longer, and procedures are invasive and associated with a considerable morbidity and mortality (Jablonski 1995; Beaujard 2000). The most frequent surgical complications are surgical site infections, anastomotic leakage, entero‐cutaneous fistulas and complications not directly related to surgery such as  cardio‐respiratory and thrombo‐embolic events. The exact incidence of these complications is unknown, as well as the influence of different technical approaches on the occurrence of these events.

Futhermore, there is no uniformity in the technical aspects and criteria for patient selection of this treatment strategy among the specialized institutions worldwide. It has been recognized that the reported survival benefit in patients treated with cytoreductive surgery and HIPEC is significantly influenced by the results of surgery and careful patient selection. Before cytoreductive surgery and HIPEC will be widely accepted as standard of care for selected patients with peritoneal carcinomatosis, recent data and analyses are needed analysing survival outcomes, morbidity and mortality rates for this procedure in order to compare it with current standards of care. 

UNRESOLVED QUESTIONS

Survival:

Two‐year survival rates of 49‐61% following cytoreductive surgery and intra‐peritoneal chemotherapy have been reported (Swellengrebel 2009). It has been recognized that the reported benefit in survival of patients treated with cytoreductive surgery and HIPEC is significantly influenced by the results of surgery and careful patient selection. In addition, the combined treatment of cytoreductive surgery and HIPEC is an invasive procedure associated with a considerable morbidity and mortality (Jablonski 1995; Beaujard 2000). There is a need to evaluate the gain in survival in order to give an objective difference comparing  results of HIPEC procedures with standard palliative treatment. 

Morbidity:

Complications of cytoreductive surgery and HIPEC are frequent. The exact incidence is unknown, as well as the influence of different technical approaches. Six studies reported the overall morbidity (Jablonski 1995;Shen 2004; Pilati 2003; Kecmanovic 2005; Yan 2006; Verwaal 2004). Before cytoreductive surgery and HIPEC will be widely accepted as standard of care for selected patients with peritoneal carcinomatosis, recent data and analyses are needed analysing survival outcomes, morbidity and mortality rates for this procedure in order to compare it with current standards of care.