Background: The new tyrosine kinase inhibitors approved for the therapy of non-small cell lung cancer (NSCLC) caused by ALK rearrangement, have been showing an improvement on overall survival, disease progression and toxicity. Method: We performed a retrospective analysis of all the patients with NSCLC and ALK rearrangement that received crizotinib, ceritinib and alectinib as first-line or second-line therapy in our health care unit, by investigating its toxicity and the disease progression. Results: Out of the 113 patients diagnosed with stage IV or stage IIIB lung adenocarcinoma, 17 were ALK positive (from those who had clinical indication and enough histologic material to perform the test). In this population, the mean age was 60,76 years-old and 76,47% (n¼13) were females. Sixteen patients (94,12%) were non-smokers and one (5,88%) was a smoker. By the time of the diagnosis, 94,12% (n¼16) presented with stage IV disease (one of them had brain metastasis and was treated with holocranial radiotherapy) and 5,88% (n¼1) presents with stage IIIB disease. 41,18% (n¼7) had a Performance Status of 0 and 58,82% (n¼10) of 1.Crizotinib was started as first-line therapy in 35,29% (n¼6) of patients and as second-line therapy in 64,71% (n¼11) (these started first with chemotherapy fulfilling either 2, 4 or 6 cycles of treatment). 10 patients showed crizotinib-induced toxicity (1 presented skin rash, 1 presented onicolisis, 6 had liver toxicity and nausea and/or diarrhea, 1 had renal toxicity and 1 presented cardiac toxicity and died). As such, crizotinib dose reduction was needed in 6 patients (4 due to liver toxicity, 1 due to renal toxicity and 1 due to skin rash) and 1 patient had his treatment shifted to ceritinib (because of liver toxicity). Considering follow-up until July 2017, complete and partial response with crizotinib was first seen in 10 and 3 patients, respectively, 3 patients presented disease progression and 1 patient doesn't have follow-up data available yet. After a period of time, 6 patients kept their response to crizotinib and 10 patients showed disease progression (4 patients evolving with cerebral, 2 with bone metastasis, and the remaining with lesions in different locations), and 2 of them eventually died. The average time under crizotinib was 14 month (minimum month and maximum 28 month). 7 of the latter had their treatment shifted to alectinib (n¼ 5) or ceritinib (n¼2). Regarding the data available so far, from the patients that started alectinib 2 showed partial response and 1 showed complete response, and from those under ceritinib 1 showed partial response and 1 showed stability of the disease. From those patients with progression with brain metastasis, 1 is currently under ceritinib (presenting disease stability) and 3 are under alectinib (1 presents complete response, 1 presents partial response, the third doesn't have available follow-up data yet). Three of these patients were treated with holocranial radiotherapy. Conclusion: The experience in our health care unit is similar to the data from ...