Awareness of KRAS testing by oncologists and panitumumab use in colorectal cancer patients: A European survey.

Abstract

547 Background: Panitumumab (Pmab) is licensed for treatment in metastatic colorectal cancer (mCRC) patients with wild type KRAS mutation status (US) and wild type RAS (KRAS and NRAS) mutation status (most other countries). To resolve uncertainties about KRAS testing, a survey and medical records review (MRR) are being carried out in Europe in three rounds: the first two rounds (2012-2013) evaluated KRAS testing and round 3 is evaluating RAS testing. These studies are specific obligations in Europe for the conditional marketing authorization for Pmab. Here we present results of rounds 1 and 2. Methods: Eligible oncologists were contacted by telephone in nine European countries (France, Germany, Italy, Spain, Czech Republic, Netherlands, Belgium, Denmark, and Sweden). To be eligible, the physician was required to be a practicing oncologist and have prescribed Pmab to mCRC patients. Results: 299 of 301 (99.3%) oncologists participating in the survey were aware of the need to perform KRAS testing prior to first dose of Pmab and 294 (97.7%) were aware of patients’ KRAS mutation status prior to first dose. 283 of 301 (94.0%) did not prescribe Pmab to mCRC patients with mutant or unknown KRAS status. 164 physicians administered Pmab simultaneously with oxaliplatin-containing chemotherapy to patients and 10 (6.1%) to patients with mutant or unknown KRAS status. 306 patients from 79 participating oncologists were included in the MRR. 302 of 306 mCRC patients (98.7%) were tested for KRAS tumor status, known by the oncologist before first dose of Pmab. 299 of 302 patients (99.0%) had wild-type KRAS tumor status. 83 of 85 patients (97.6%) treated with Pmab and oxaliplatin-containing chemotherapy had wild-type KRAS tumor status. 55 of 56 linked pathology laboratories (98.2%) participated in a Quality Assurance scheme; all used a CE marked or otherwise validated KRAS detection method. Conclusions: Results from both studies show a high level of knowledge among oncologists of the need for KRAS testing in mCRC patients prior to treatment with Pmab and the contraindication with oxaliplatin-containing chemotherapy with mutant or unknown KRAS tumour status. The final round of this study evaluating RAS testing in Europe is currently underway.