Feasibility Study to Estimate Number of Patients With Precancerous Areas in Their Airways and the Response to Gefitinib

* Age 18 years or above * Resected NSCLC or Squamous cell Head \& Neck cancer treated curatively * All treatment, including any adjuvant treatment with radiotherapy and/or chemotherapy completed at least 3 months prior to study entry * ECOG (Eastern Cooperative Oncology Group) performance status of 0 or 1 * Suitable for flexible bronchoscopy * Able to give signed informed consent * Adequate haematological, kidney and liver function: * Serum alanine transaminase (ALT) ≤2.5 x upper limit of normal (ULN) * Total serum bilirubin ≤1.5 x ULN * Absolute neutrophil count (ANC) ≥1500/μL * Platelets ≥100,000/μL * Haemoglobin ≥9.0 g/dL * Sufficient renal function to allow administration of contrast medium (in line with Royal College of Radiologists guidelines). In addition, the following inclusion criteria must be met during the screening period in order to confirm eligibility for the study treatment * No evidence of malignant disease activity on screening * High grade dysplasia on autofluorescence bronchoscopy analysis * No evidence of pulmonary fibrosis or interstitial lung disease on screening CT Exclusion Criteria: * Diagnosis of any second malignancy within the 5 years from date of enrolment, except basal cell carcinoma, squamous cell skin cancer, or in situ carcinoma of the cervix uteri that has been adequately treated with no evidence of recurrent disease for 12 months * Evidence of severe or uncontrolled systemic disease or psychiatric disorder that would interfere with the patient's safety * Known severe hypersensitivity to Gefitinib or any of the excipients of the product * Past medical history of interstitial lung disease, drug-induced interstitial disease, radiation pneumonitis which required steroid treatment or any evidence of clinically active interstitial lung disease * Pre-existing idiopathic pulmonary fibrosis * History of allergy to contrast medium * Insufficient lung function as determined by either clinical examination or an arterial oxygen tension (PaO2) of \< 9.3kpa * Inability to swallow oral medications * Presence of active inflammatory bowel disease, partial or complete bowel obstruction or chronic diarrhoea or any condition which would interfere with absorption of an oral drug. * Past medical history of keratitis * Past medical history of Sjogren's syndrome * Pregnant or breast-feeding * Male and female patients (of childbearing age) not using, or not willing to use, protocol mandated contraception * Prior EGFR inhibitor use. * Concurrent medication with known potent CYP3A4 inhibitors and inducers and/or dosing within 7 days of date of enrolment (e.g.. ketoconazole, rifampin, phenytoin, carbamazepine, barbiturates or herbal preparations containing St John's wort/Hypericum perforatum etc.) or use of other concomitant medication incompatible with study drug (see SmPC) * Current treatment on another therapeutic clinical trial or previous investigational agent in the last 12 weeks (supportive care trials or non-treatment trials are allowed) * Previous enrolment or treatment in the present study.