Aim of the study: To investigate the incidence and clinical implications of venous thromboembolism (VTE) in advanced colorectal cancer (ACC) patients treated and followed-up through a prospective randomised trial, comparing FOLFIRI chemotherapy given as an intermittent or as a continuous schedule.
Patients, materials and methods: 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.
Results: 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).
Conclusion: 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.