In the last years several reports have assessed the feasibility of treatment cessation in patients in persistent deep molecular response (DMR). These studies tried to identify predictive factors of a successful TFR but the results have been inconsistent. However, treatment duration has been shown to be a significant factor in several reports, including both the STIM and the EUROSKI trials. Sokal score, MR duration and response to first line TKI treatment are also quite frequently reported as predictive factors, and it has been proposed to take them into account along with treatment duration when considering a patient for a TFR attemp. At present, although definitive recommendations for treatment discontinuation cannot be given, minimum requirement for stopping treatment have been proposed: achievement of MR4 or lower response maintained for 2 years; follow-up in a center where standardized molecular biology is performed. Nowadays inclusion of patients in clinical trials is suggested whenever possible but many physicians have already started to introduce TKI discontinuation in the clinical practice. We are reporting the results of an observational study performed in Italy including patients that discontinued imatinib and 2nd generation TKIs.