229 Background: Given their prevalence, colorectal and lung cancer are treated in both academic and community settings. Appropriate use of targeted therapies in these diseases is challenging given the need for biomarker testing prior to use. Rapidly changing practice standards, limited resources, and barriers to tissue processing make this particularly challenging in the community. We examined the use of biomarker testing and targeted therapies in colorectal and lung cancer at one of the Dana-Farber Cancer Institute satellite sites. Methods: Patients who had their first visit for colorectal cancer between 2011 and 2014 or for lung cancer in 2014 at one site were identified using ICD-9 codes. Notes and reports were reviewed for pathology, staging, molecular testing, and treatment. Results: In 2014, 46 patients had their first visit for colon cancer. MMR testing was done in 48% (22/46) of these patients. Of the 23 patients under 70 years old (NCCN guideline), 75% (17/23) were tested. From 2011 to 2014 there were 30 patients with newly diagnosed metastatic colorectal cancer. KRAS testing was done in 73% (22/30) of these patients and three were subsequently treated with EGFR targeted therapy (all 3 KRAS/BRAF wild type). In 2014, 90 patients were seen with a new diagnosis of lung cancer. Among the 36 patients with adenocarcinoma, 21 were stage IV at diagnosis and 57% (12/21) were tested for EGFR and ALK. The most common reason cited for not testing was tissue sample size (e.g. cytology from pleural fluid, CT-guided biopsy). Among the 9 patients not tested, 6 were noted to have insufficient material and in 3, testing was not requested. Conclusions: The largest discrepancy between guidelines and clinical practice was seen in EGFR and ALK testing in lung cancer. In colorectal cancer there was high concordance with NCCN guidelines and importantly these results appropriately guided EGFR directed therapy. Possible interventions to increase utilization include educational events, reflex testing on pathology, and an algorithm to pursue additional tissue when biomarker testing could significantly change therapy.