▪Background:The myeloproliferative neoplasms (MPNs), including essential thrombocythemia (ET), polycythemia vera (PV) and myelofibrosis (MF) can be characterized by heterogeneous symptoms, disease features, and prognosis. Timely monitoring of blood counts and if needed, referral for discussion of stem cell transplant (SCT), are critical to optimizing survival and quality of life. In connection with the MPN SCT Transplantation Timing Taskforce's (MS3T's) work in developing the DIPPS-based Stem Cell Spectrum Timing Tool, the survey was deployed to explore factors contributing to delayed entry to SCT. National Comprehensive Cancer Network (NCCN) guidelines for MPNs strongly recommend referral to specialized centers with expertise in the management of MPNs (Mesa et. al. 2017). To date, efforts to assess the timing and quality of MPN patient care from the patient's perspective have been minimal.Methods:Patients were recruited from MPN-related Facebook pages, subscribers of MPNforum Magazine and E-mail support groups including the MPN-NET, MPDchat, and the MPN Research Foundation. Hematologists, MPN patients, and advocates constructed the 11-item survey questions and content. The survey was available for patient response between July 4-11th2018. Patients were queried on MPN type, time of diagnosis, and details regarding knowledge of their MPN disease features and care.Data:Demographics.Overall 2382 MPN patients responded to the online survey. Of these, 901 (38%) patients had ET, 865 (36%) had PV, 561 (24%) had MF, 41 (2%) had MPN-unclassifiable or MPN/MDS overlap and 15 (1%) did not respond. Among MF patients, 56% reported having primary MF, 42% secondary MF, 1% prefibrotic MF, and 1% reported having already undergone SCT (1% did not specify type of MF or transplant). The majority of patients were diagnosed with their MPN by a hematology/oncology (77.8%) or family practice (15 %) physician.MPN Care provider and monitoring: Out of all respondents, 35% reported being cared for by an MPN specialist, 36% were not cared for by an MPN specialist and 27% were unsure if their provider was an MPN specialist. Overall less than half (42%) of patients reported having sought a second opinion from an MPN specialist. The majority (87%) of participants knew their mutational status relating to the highly publicized and widely tested JAK2 V617F mutation (73.8%) and CALR (10.2%). However, a statistically insignificant number of patients had any idea of other driving and secondary mutations including MPL, EZH2, SRSF2, IDH1/2 or ASLX-1. Blood counts were reviewed by a hematologist for the majority of patients (93% responded “yes”, 4% responded “sometimes”, 3% responded “no”).SCT Referral: Among ET and PV, <1% of patients reported being referred to SCT. For MF, 34% of participants reported having been referred for SCT discussion (30% for primary MF and 28% for secondary MF).Conclusions: MPN patients often report receiving care outside of the care of an MPN specialist. Additionally, despite the poor outcomes and higher likelihood of progression to AML, less than a third of patients with secondary MF report being referred for SCT discussion. Independent validation of patient responses, particularly in regards to MPN specialized care and timing of transplant discussion should be investigated further. However, these patient responses suggest many patients may be receiving less than optimal MPN care. These results demonstrate the importance of community hematology/oncology physician and patient education regarding optimal MPN care. DisclosuresMesa:UT Health San Antonio - Mays Cancer Center: Employment; Celgene: Research Funding; Novartis: Consultancy; Incyte Corporation: Research Funding; Pfizer: Research Funding; CTI Biopharma: Research Funding; Genentech: Research Funding; Promedior: Research Funding; NS Pharma: Research Funding; Gilead: Research Funding. Palmer:Novartis: Research Funding. Harrison:Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; CTI BioPharma: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Speakers Bureau. Verstovsek:Italfarmaco: Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Scherber:Gilead: Honoraria.