Observing Patients With Palliative Asymptomatic Centrally Located Advanced Non-small Cell Lung Carcinoma (NSCLC)

Inclusion Criteria: * Histologically or cytologically confirmed NSCLC * Central disease, as defined by tumour (either primary or nodal disease) arising or extending within a 2cm circumferential expansion from the centre of the trachea or within the zone of the proximal bronchial tree * Disease is visible on thoracic CT (diagnostic or simulation) * Asymptomatic from intra-thoracic tumour (may have background chest symptoms related to underlying COAD etc, but these symptoms must not have worsened due to tumour) * Patient (due to age or co-morbidities) or tumour (due to locally advanced or metastatic disease) is not suitable for radical treatment (defined as surgery or RT dose \>50Gy in 20 fractions or equivalent). * Previous chemotherapy, thoracic RT or surgery is allowed * RT to other metastases (e.g. brain, bone etc) is allowed •≥ 18 years of age * Able to provide written informed consent Exclusion Criteria: * Intra-thoracic disease is peripheral only, not extending within 2cm of trachea/proximal bronchial tree * Symptomatic from intra-thoracic NSCLC * Histological diagnosis of small cell lung cancer, or malignant mediastinal lymphadenopathy from another malignancy (not NSCLC)