248 Background: The National Comprehensive Cancer Network (NCCN) invites petitions to its scientific panels. Most ( > 95%) are from the pharmaceutical industry lobbying to include their products in the NCCN Guidelines. Rarely, physicians request scientific scrutiny of the guidelines. We report the experience of Oncology Analytics (OA) with petition submissions and the possible impact on guidelines. Methods: From 2011-2015, OA made 7 petitions to NCCN. The content of each was tracked into subsequent NCCN Guidelines to ascertain whether any changes resulted. Results: 1) The Survivorship Panel was petitioned to add liposomal doxorubicin to the list of cardiotoxic anthracyclines: No changes were made. 2-3) The NSCLC Panel was asked in 2014 to remove the category 2A listing for trastuzumab and afatinib as HER-2 targeted drugs, and cabozantinib as a RET rearrangement target based on absence of phase I-III full text scientific literature. This was done, however, cabozantinib was reverted to 2A status late 2015 based on abstract-only data. 4) Per FDA approval, the NSCLC Panel was asked to recommend bevacizumab only in combination with carboplatin/paclitaxel for 1st line non-squamous NSCLC based on a survival advantage in ECOG 4599: No changes were made. 5) Given the FDA-approval, the Ovarian Cancer Panel was requested to add doxorubicin: This was done. 6) A 2012 Supportive Care Panel petition pointed out the absence of data supporting palonosetron as the preferred 5-HT3 antagonist with aprepitant for moderate or high emetic risk chemotherapy: No change was made upon request; however, preferred status was removed in 2015 from high emetic risk. 7) Based on a preponderance of evidence, a Supportive Care Panel petition requested re-categorization of the febrile neutropenia risk for carboplatin/paclitaxel from intermediate to low except in patients of Japanese ancestry and/or carboplatin AUC > 6: This was done. Conclusions: Majority of NCCN physician petitions came from OA, yet constituted less than 5% of all petitions submitted. NCCN does not provide direct petitioner feedback, so we cannot say for certain that our petitions led to changes in subsequent guidelines. Not all requests resulted in NCCN changes, despite level one supportive data or accentuating an absence of data.