Neoadjuvant Treatment With Atezolizumab and Atezolizumab as Maintenance for the Treatment of Stage III Non Small-Cell Lung Cancer (NSCLC)

Inclusion Criteria: * Previously untreated patients with histologically- or cytologically- documented Non Small-Cell Lung Cancer (NSCLC) who present stage IIIA - IIIB disease (according to 8th version of the International Association for the Study of Lung Cancer Staging Manual in Thoracic Oncology) * Confirm the absence of distant disease * ECOG (Performance status) 0-1 * Adequate hematologic and organ function * All patients are notified of the investigational nature of this study and signed a written in-formed consent in accordance with institutional and national guidelines, including the Declaration of Helsinki prior to any trial-related intervention * Adequate lung function * Patients aged \> 18 years * For female patients of childbearing potential, agreement (by patient and/or partner) to use a highly effective form(s) of contraception * For male patients with female partners of childbearing potential, agreement (by patient and/or partner) to use a highly effective form of contraception * Oral contraception should always be combined with an additional contraceptive method * Women who are not postmenopausal or surgically sterile must have a negative serum pregnancy test result within 8 days prior to initiation of study drug. * Patient capable of proper therapeutic compliance and accessible for correct follow-up Exclusion Criteria: * Patients mutation or an amplification in the EGFRgene, ALK fusion oncogene. * Known STK-11 ligand alterations, MDM2 amplifications or ROS1 translocations. * Weight loss \>10% within the previous 3 months. * Patients that receive previous treatment with antineoplasic drugs, chest radiotherapy, or previous surgery for lung cancer. * Malignancies other than Non Small-Cell Lung Cancer (NSCLC) within 3 years prior to enrolment * Pleural or pericardial effusion * Known hypersensitivity or allergy to atezolizumab formulation. * History of autoimmune disease or lung disease * Positive test for human immunodeficiency viruses (HIV) * Patients with active hepatitis B or hepatitis C or psitive for hepatitis C virus. * Active tuberculosis. * Symptomatic neuropathy grade \> 1 according to Common Terminology Criteria for Adverse Events (CTCAE) v5.0 * Severe infections within 4 weeks prior to be included in the study