psychological assessments include changes in domains related to physical, mental, emotional and social functioning, depression, sleep quality and distress. In case of documented clinical benefit, the study allows to patients to remain on treatment beyond progression. Result: From February 2016, a total of 34 patients have been evaluated: 2 of them were registered as screening failures for symptomatic brain metastases and lack of compliance, respectively. The 32 patients enrolled have a median age of 67,6 years (range 40-84 years), are predominantly female (65,6%), with ECOG performance status 0 (68,7%) and a non-smoking history (75,0%). Activating EGFR mutation at diagnosis have been described on exon 19 and 21 in 62,5% and 28,1% of cases, respectively. Only four patients had brain metastases at study entry. Osimertinib has been used as second-line treatment, after failure of first-line TKI, in 78,1% of cases. On the date of 1 June 2017, ten patients have interrupted the treatment for disease progression, with a median duration of therapy equal to 6,69 months (range 2,80-11,20 months). Conclusion: Data concerning the tolerability of treatment with Osimertinib in EGFR-T790M+ NSCLC patients, their perception of symptomatic AEs together with the psychological issues evaluated in the ARPA study, are not mature. Great expectations come from this study which reflects a real world population, and the hope of the investigators is to highlight the critical aspects for patients in order to better manage their treatment and the psychological issues.