Background: Self-expanding metal stents (SEMS) are increasingly used in the treatment of malignant large bowel obstruction in the setting of inoperable colorectal cancer. Perforation is a well-known complication associated with these devices. The addition of the vascular endothelial growth factor inhibitor bevacizumab is suspected to increase the rate, but the extent of the increase is not known. Methods:We retrospectively reviewed the records of patients receiving SEMS in tertiary hospitals in Calgary, Alta., between October 2001 and January 2012. Results:We reviewed the records of 87 patients with inoperable colorectal cancer who received SEMS during our study period. Nine perforations occurred in total: 4 of 30 (13%) patients who received no chemotherapy, 3 of 47 (6%) who received chemotherapy but no bevacizumab, and 2 of 10 (20%) who received chemotherapy and bevacizumab. These two patients received bevacizumab with FOLFIRI after SEMS placement, and they had peritoneal disease. Conclusion:Our case series and other studies suggest that bevacizumab may increase the risk of colonic perforation in the setting of SEMS. Caution should be used when combining these therapies.

Sunitinib is an oral multikinase inhibitor that blocks the vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) alpha and beta, c-kit, and other receptors. These attributes have proven to be efficacious in the treatment of metastatic renal cell carcinoma (RCC), unresectable gastrointestinal stromal tumors (GIST), and well-differentiated advanced pancreatic neuroendocrine tumors (PNET). Though activity has been reported in other tumor types, phase III trials have not yet demonstrated improved survival outcomes in these cancers. Most side effects including hypertension, hand-foot syndrome, and diarrhea are generally well manageable. This review will detail the preclinical data leading up to the results of the pivotal phase III clinical trials that have led to the widespread use of sunitinib in advanced RCC, GIST, and PNET.

Background The optimal management of hypomagnesemia (hMg) induced by epidermal growth factor receptor inhibitors (egfris) for advanced colorectal cancer is unclear. We surveyed gastrointestinal medical oncologists in Canada to determine practice patterns for the management of egfri-induced hMg.Methods Based on distribution lists from the Eastern Canadian Colorectal Cancer Consensus Conference and the Western Canadian Gastrointestinal Cancer Consensus Conference, medical oncologists were invited to participate in an online questionnaire between November 2013 and February 2014.Results From the 104 eligible physicians, 40 responses were obtained (38.5%). Panitumumab was more commonly prescribed than cetuximab by 70% of respondents, with 25% prescribing cetuximab and panitumumab equally. Most respondents obtain a serum magnesium level before initiating a patient on an egfri (92.5%) and before every treatment (90%). Most use a reactive strategy for magnesium supplementation (90%) and, when using supplementation, favour intravenous (iv) alone (40%) or iv and oral (45%) dosing. Magnesium sulfate was used for iv replacement, and the most common oral strategies were magnesium oxide (36.4%) and magnesium rougier (18.2%). Under the reactive strategy, intervention occurred at hMg grade 1 (70.3%) or grade 2 (27%). Of the survey respondents, 45% felt that 1–5 of their patients have ever developed symptoms attributable to hMg, and 35% have had to interrupt egfri therapy because of this toxicity, most commonly at grade 3 (30%) or grade 4 (45%) hMg. The most important question about egfri-induced hMg was its relevance to clinical outcomes (45%) and its symptoms (37.5%).Conclusions In Canada, various strategies are used in the management of egfri-induced hMg, including prophylactic and reactive approaches that incorporate iv, oral, or a combination of iv and oral supplementation. Clinicians are concerned about the effect of hMg on clinical outcomes and about the symptoms that patients experience as a result of this toxicity.about the symptoms that patients experience as a result of this toxicity.