Afatinib In Combination With Cisplatin Or Carboplatin + Pemetrexed In Patients With EGFR-Mutant Lung Cancers Undergoing Definitive Chemoradiation

Inclusion Criteria: * Unresectable or inoperable, stage III or locoregional recurrence without evidence of distant, metastatic disease * Pathologic confirmation of NSCLC at MSKCC * Documentation of a sensitizing EGFR mutation * Age ≥ 18 years * No contraindication to definitive thoracic radiation therapy with concurrent chemotherapy Adequate organ function as defined by: * Calculated creatinine clearance≥ 45 mL/min (by Cockcroft-Gault) * Total bilirubin less than 1.5 x ULN (unless known Gilbert's disease) and AST/ALT less than 3 x ULN * Absolute neutrophil count greater than 1500/mm3 * Platelet count greater than 100,000/mm3 * Women of childbearing age must have a negative blood pregnancy test * Men and women of childbearing potential must be willing to use effective contraception while on treatment and for at least 3 months there after Exclusion Criteria: * Prior chemotherapy or radiation therapy for this lung cancer (history of prior lung cancer that has been treated and deeded inactive by the clinician is acceptable) * Ineligible for cisplatin or carboplatin per medical oncologist * Ineligible for pemetrexed per medical oncologist * Greater than minimal, exudative, or malignant pleural effusion * Calculated creatinine clearance by Cockcroft \& Gault method ≤45 ml/min * Unstable congestive heart failure * Ejection fraction \<50% as assessed by MUGA or echocardiogram * Interstitial lung disease * Patient requiring on-going treatment with a potent inhibitor (cyclosporin, erythromycin, ketoconazole, itraconazole, quinidine, phenobarbital with quinidine, ritonavir, valspodar, verapamil) or inducer of P-gp (St. John's wort or rifampin) * Women who are breastfeeding