Malignant Bowel Occlusion: An Update on Current Available Treatments

Abstract

Malignant bowel obstruction (MBO) is a critical complication occurring in patients with advanced malignancy. Current treatments are both surgical and non-surgical, the latter including medical, endoscopic, and percutaneous approaches. Surgery is still the treatment of choice for MBO. However, almost 50% of patients are unfit for surgery because of poor performance status. Given the high post-operative mortality rate and the frailty of MBO patients, the least invasive surgical intervention is recommended. Therefore, recent multidisciplinary recommendations have suggested considering less invasive interventions instead of palliative surgery. Medical therapy, aiming to alleviate symptoms, is usually only a part of the therapeutic strategy when managing patients with MBO. Percutaneous techniques, including both interventional radiology and endoscopic procedures, are safe and effective for symptom relief, but often do not allow oral diet resumption. Endoscopic techniques are achieving a more relevant role for MBO treatment, as supported by the widening of the indication to colonic intraluminal stenting in the latest update of the European guidelines. Current data support the use of colonic stenting as both a bridge to surgery and the definitive treatment of malignant colonic obstruction. The development of endoscopic ultrasound-guided anastomotic techniques may offer the possibility of widening its applications to endoscopic treatment of MBO, allowing stenosis to be overcome, and reestablishing the continuity of the gastrointestinal tract in small bowel obstructions as well. The introduction of new interventional endoscopic techniques and their progressive diffusion will add the possibility to adopt minimally invasive solutions to treat a critical condition such as MBO.

Keywords: EUS-EC; EUS-guided anastomosis; MBO; MCO; MSBO; malignant bowel occlusion; malignant colonic occlusion; malignant small bowel occlusion.

Figure 1

(panels a–d) Sequential steps of endoscopic placement of a self-expanding metal stent for the treatment of a left-sided malignant colonic obstruction due to metastatic colorectal cancer. In this case, an over the wire technique has been used. First, a guidewire and a Huibregtse catheter have been passed through the stenosis under endoscopic and fluoroscopic guidance (panel a). Then, a colonic uncovered metal stent has been placed under fluoroscopic guidance (panel b) and progressively released (panel c). Endoscopic control confirms the correct placement of the stent (panel d).

Figure 1

(panels a–d) Sequential steps of endoscopic placement of a self-expanding metal stent for the treatment of a left-sided malignant colonic obstruction due to metastatic colorectal cancer. In this case, an over the wire technique has been used. First, a guidewire and a Huibregtse catheter have been passed through the stenosis under endoscopic and fluoroscopic guidance (panel a). Then, a colonic uncovered metal stent has been placed under fluoroscopic guidance (panel b) and progressively released (panel c). Endoscopic control confirms the correct placement of the stent (panel d).

Figure 2

(panels a–d) Endoscopic ultrasound (EUS)-guided entero-colostomy performed in a patient with malignant colonic obstruction due to carcinosis from an advanced cholangiocarcinoma. The patients had previously undergone an EUS-guided gastroenteroanastomosis lumen-apposing metal stenting (LAMS), as shown in a plain RX study of the same day of the procedure (arrow, panel a). A therapeutic linear echoendoscope is advanced transanally until an adequate endosonographic window is reached (panel b). Then, with endosonographic and fluoroscopic guidance, the LAMS is released (panels c–e). The technical success is confirmed by passage of feces and contrast through the LAMS (panel f).

Figure 2

(panels a–d) Endoscopic ultrasound (EUS)-guided entero-colostomy performed in a patient with malignant colonic obstruction due to carcinosis from an advanced cholangiocarcinoma. The patients had previously undergone an EUS-guided gastroenteroanastomosis lumen-apposing metal stenting (LAMS), as shown in a plain RX study of the same day of the procedure (arrow, panel a). A therapeutic linear echoendoscope is advanced transanally until an adequate endosonographic window is reached (panel b). Then, with endosonographic and fluoroscopic guidance, the LAMS is released (panels c–e). The technical success is confirmed by passage of feces and contrast through the LAMS (panel f).

Figure 3

Proposed algorithm for the treatment of malignant bowel obstruction. Legends: MBO—malignant bowel obstruction; MCO—malignant colonic obstruction; MSBO—malignant small bowel obstruction; EUS-EC—endoscopic ultrasound (EUS)-guided entero-colostomy; EUS-CC—endoscopic ultrasound (EUS)-guided colo-colostomy.