A total of 266 patients were randomised by 15 experimental centres: 168 (63.2 % ) were males, median age: 64.6 years, age range: 37–76 years. Almost all (95.5 % ) patients had metastatic disease, while the remainder were classified with locally advanced irresectable disease. For 138 (51.9 % ) of the patients, the chemotherapy treatment was intermittent FOLFIRI and the remaining patients received continuous treatment. All toxicities, including VTE, were prospectively collected.
During the study protocol, the central data management gathered two cases of VTE. Our analysis retrieved 27 (10.2 % ) patients who developed a VTE, almost all (89 % ) during the course of chemotherapy treatment: 20 out of 27 during FOLFIRI, the remaining 7 during following lines or follow-up. VTE was the most frequent grade 3/4 toxicity. The incidence of VTE was significantly increased in the patients receiving continuous rather than intermittent treatment (HR 2.67, 95 % CI 1.17–6.10; p < 0.02).
VTE is a common complication among advanced colorectal cancer patients and yet this type of toxicity is widely underestimated. In this randomised trial, VTE was the most frequent grade 3/4 toxicity. Use of an intermittent schedule is associated with a reduced risk of developing VTE.