optimizing treatment for obstructive colon cancer
Femke Amelung is a PhD student in the research group Robotics and Mechatronics. Her supervisors are prof.dr. I.A.M.J. Broeders from the Faculty of Electrical Engineering, Mathematics and Computer Science and prof.dr. P.D. Siersema from the Radboud University Medical Center.
Colon cancer is the third most common cancer worldwide and it’s incidence is annually increasing. In the Netherlands alone, over 15.000 new cases are diagnosed each year. Most of these patients present with non-specific symptoms such as fatigue, weight loss or a changed stool pattern. Further diagnostic tests can then lead to the diagnosis of colorectal cancer. In nine to thirteen percent of patients with colorectal cancer however, acute colonic obstruction is the first symptom.
The majority of patients presenting with an acute colonic obstruction are elderly and in a poor clinical condition due to several days to weeks of reduced intake and significant weight loss. Furthermore, presentation with acute colonic obstruction is associated with more advanced disease and a higher incidence of metastatic disease. These factors all contribute to an increased peri- and postoperative surgical risk.
Currently, emergency resection is the most applied treatment approach, even though this procedure is associated with morbidity and mortality rates up to 60% and 22%, respectively. In high-risk patients (ASA >2 and age >70 years), mortality is even as high as 32.2%.
These outcomes have prompted the search for a valid and safe alternative. This alternative has possibly been found in a bridge to surgery (BTS) approach, with the aim to achieve initial colonic decompression using a minimally invasive procedure. Hereby, the risks of colonic obstruction are addressed immediately and fecal passage is restored with the objective to reduce bowel wall distention. This creates time to optimize the patients’ condition prior to elective resection and to perform adequate tumor staging. By doing this, extensive surgery in patients with disseminated disease or unacceptable surgical risk can be avoided, since a BTS approach can then serve as a definite palliative measure. Colonic decompression as bridge to surgery can be achieved by construction of a deviating stoma (DS) or by placement of a self-expandable metallic stent (SEMS).
In part one of this thesis, we focus on determining which treatment approach is best for patients with a righ-sided obstructing tumor. Currently, a bridge to surgery approach is not a standard treatment approach in these patients, even though morbidity and mortality following emergency resection is similar to those in patients with a left-sided obstruction. In part I we present evidence that a bridge to surgery approach might also benefit patient with a right-sided obstructing tumor, with more laparoscopic resections, more primary anastomosis and fewer (temporary) stoma’s.
In part II we focus on left-sided tumors specifically. A bridge to surgery approach is more accepted in these patients. Especially stent placement has been extensively researched in the past years. However, data is lacking on stoma construction as a bridge to surgery approach. In part II the safety and possible advantages of this approach were studied. Both bridge to surgery approaches seem to offer the same advantages of more laparoscopic surgeries, more primary anastomosis and fewer stoma’s. In addition, stoma construction does not seem to influence long-term oncologic outcomes. Indeed, the use of this treatment approach has increased significantly in the past years.
In the third and final part of this thesis we focus specifically on long-term outcomes. Especially stent placement has been associated with a negative influence on long-term oncologic outcomes. A systematic review of all literature on long-term outcomes following stent placement and a large matched analysis did not show a difference in oncologic outcome following stent placement or emergency resection. In addition, we found a higher incidence of incisional hernia’s following stoma reversal.
