559P - Patterns of venous thromboembolism risk in patients with localized colorectal cancer undergoing adjuvant chemotherapy or active surveillance

Date 08 October 2016
Event ESMO 2016 Congress
Session Poster Display
Topics Colon and Rectal Cancer
Presenter Jakob Riedl
Citation Annals of Oncology (2016) 27 (6): 149-206. 10.1093/annonc/mdw370
Authors J. Riedl1, F. Posch1, M. Stotz1, A. Bezan1, T. Winder2, R. Schaberl-Moser1, M. Pichler1, H. Stoeger1, A. Gerger1
  • 1Clinical Division Of Medical Oncology, Department Of Internal Medicine, Medical University Graz, 8036 Graz - Graz/AT
  • 2Medizinische Onkologie, Universitätsspital Zürich, 8091 - Zürich/CH

Abstract

Background

The risk of cancer-associated venous thromboembolism (VTE) is highly elevated in pts w/ metastatic colorectal cancer (CRC), and in particular during antineoplastic therapy. However, patterns of VTE risk in pts w/ localized CRC are unclear. Here, we estimate the risk of VTE in CRC pts after curative surgery, and define its association with baseline risk factors, adjuvant chemotherapy (adjCTX), disease recurrence, and death.

Methods

In this single-center historical cohort study, 562 pts w/ CRC (median age = 65.3 years; stages I, II, and III: n = 29, (5.2%), n = 160 (28.7%), n = 368 (66.1%); adjCTX: n = 346 (61.7%)) were included at the time of surgery and followed-up until the onset of VTE, disease recurrence, and death. The primary endpoint of this study was the cumulative incidence of objectively-confirmed, symptomatic or incidental deep vein thrombosis and/or pulmonary embolism (VTE), accounting for death as a competing risk.

Results

During a median follow-up of 2.9 years, we observed 18 VTE events (3.2%), 142 recurrences (25.3%), and 52 pts (9.3%) died. The 6-month, 1-year, and 5-year risk of VTE was 1.4%, 1.8%, and 3.3%, respectively. In univariable time-to-VTE regression, adjCTX was not associated with an increased risk of VTE (Subdistribution hazard ratio = 1.03, 95%CI: 0.40-2.66, p = 0.95). In multi-state analysis, the onset of disease recurrence emerged to be associated w/ an excessive increase in the risk of VTE (Transition hazard ratio (THR) = 11.8, 95%CI: 4.02-35.81, p 

Conclusions

The risk of VTE in pts w/ localized CRC undergoing curative surgery is very low. Importantly, adjCTX does not appear to be a risk factor for VTE in this setting. Therefore, the role of primary thromboprophylaxis during adjCTX is likely of low clinical benefit. The by far strongest determinant of VTE risk in curatively treated CRC pts turned out to be disease recurrence. Conversely, VTE emerged as a risk factor for recurrence, which indicates that VTE can be an early clinical sign for recurrent disease in this patient population.

Clinical trial identification

Legal entity responsible for the study

Medical University of Graz

Funding

Medical University of Graz

Disclosure

All authors have declared no conflicts of interest.