Single center analysis of immunotherapy in mCRC patients

• Published in: Journal of clinical oncology Vol. 30; no. 15_suppl; p. e14087
• Main Authors: Ruckser, Reinhard, Hoenigschnabl, Selma, Kitzweger, Elvira, Tatzreiter, Georg, Kier, Peter, Habertheuer, Karlheinz, Zelenka, Peter, Buxhofer-Ausch, Veronika, Reiner-Concin, Angelika, Sebesta, Christian
• Format: Journal Article
• Language: English
• Published: 20.05.2012
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/jco.2012.30.15_suppl.e14087

Abstract only e14087 Background: Immunotherapy in real-life, unselected patients with metastatic colorectal cancer (mCRC) was analyzed retrospectively at a single center in Austria. Methods: We have treated 137 mCRC patients with at least one antibody containing therapy since 2004 at our center based at data available at that time and patient eligibility. Results: Most mCRC patients were between 55 and 75 years old. The KRAS mutation testing performed routinely from 2008 onwards shows a distribution of 55 % wildtype (wt) and 45% mutant (mut) KRAS. Median overall survival (OS) was 24 months (n=82) with a trend towards greater benefit for KRAS wt patients compared to KRAS mut (26.8 vs. 20.9 months, respectively). Most patients received between 3 and 5 treatment lines. 40% of patients were treated with 5 therapies and 8% reached treatment line 8. The median OS correlated with the number of therapy lines. Chemotherapy alone regimens are decreasing constantly due to the establishment of biomarker analysis based treatment decisions and the increase in available antibodies for immunotherapy in mCRC. Based on direct positive experience with various antibodies, we were successfully treating patients repeatedly with the same antibodies in non-consecutive treatment lines. 75.7% of all patients treated with Cetuximab received the antibody only once during 3.8 therapy lines. 13% of patients who obtained the agent in two lines received on average 5.7 treatment lines resulting in improved OS. This was even more prominent in 8.5% patients receiving Cetuximab in 3 lines with a trend towards further OS benefit. These data describe that multiple applications of the same antibody is not only feasible but also very effective. Conclusions: By taping the full potential of treatment options, optimizing their usage and expanding the number of treatment lines we could achieve a median OS in real-life patients similar to that previously described in large phase III studies. Our analysis describes the following key factors for reproducing clinical benefits reported in large trials: biomarker assessment, early and if possible multiple applications of available therapeutic antibodies, treatment until progression and use of supportive therapy to alleviate possible toxicities.