603P - Frequency of Second and Third Line Treatment Among Elderly Medicare Stage 4 Colon Cancer Patients

Abstract

ABSTRACT Background Stage 4 colon cancer (CC4) patients may receive multiple lines of chemotherapy and/or biologics as treatment (TX) to improve survival or quality of life. The tendency to use less aggressive treatment with elderly CC4 patients suggests that elderly CC4 patients may receive fewer TX lines than equivalent younger patients. Methods Elderly (65+) SEER-Medicare patients diagnosed with CC4 in 2003-2007 were followed through death or 2009 to examine variation across sub-groups in the number of TX lines. We examined NCCN treatments that included any combination of 5-fluorouracil and/or (levo) leucovorin (5FU/LV), irinotecan (IRI), oxaliplatin (OX), and bevacizumab, cetuximab, or panitumumab (collectively identified as BIOLOGICS). Certain non-NCCN treatments were also considered as possible last TX line. A hierarchy categorized treatments as: 1) IROX (IRI + OX); 2) IRI or OX; 3) 5FU/LV; 4) BIOLOGICS without chemotherapy; and 5) other TX. Gaps in TX or changes from OX or IRI to 5FU/LV were not considered new lines. Results Of 7,937 elderly CC4 patients, 3,263 (41%) received any TX, while 1,166 (15% of all, 36% of TX) and 244 (3% of all, 7% of TX) received second and third line TX, respectively. Fewer than 1% of treated patients had a fourth TX line. Among the TX group, relatively younger (p Conclusions One in three elderly CC4 patients who received initial TX received a second TX line. The likelihood of having a second TX line was associated with age, marital status, urbanicity, and comorbidity burden. Only one in fourteen elderly CC4 patients had a third TX. Disclosure C.D. Mullins: C. Daniel Mullins, PhD receives consulting income from Amgen, Bayer, BMS, Celgene, GSK, Mitsubishi, Novartis, Novo Nordisk, Novartis, and Pfizer. He also receives research funding from Bayer and Pfizer. E. Onukwugha: Ebere Onukwugha receives consulting income from Pfizer and grant support from Bayer, Novartis, and Pfizer. B. Seal: Brian Seal is an employee of Bayer HealthCare. All other authors have declared no conflicts of interest.