Second- and third-line chemotherapy regimens in elderly Medicare stage IV colon cancer patients.

e14056 Background: The NCCN guidelines for stage 4 colon cancer (CC4) patients provide general guidance on which chemotherapies and targeted therapies improve survival or quality of life but do not provide specific treatment (TX) recommendations. The guidelines suggest that TX is highly individualized and no single treatment is right for everyone. This leads to variation in both the number and types of TX lines, especially for elderly patients where there are larger evidence gaps. 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. TX included 5-fluorouracil and (levo)leucovorin-based (5FU/LV); irinotecan (IRI) and/or oxaliplatin (OX) with/out 5FU/LV; bevacizumab, cetuximab, or panitumumab (MNCLA), alone or in combination with chemotherapy; and other TX. A hierarchy categorized treatments as: 1) IROX (IRI+OX); 2) IRI or OX; 3) 5FU/LV; 4) MNCLA without chemotherapy; and 5) other T...