 Although every tumor is different with respect to the speed with which it grows and spreads, it is obvious that time plays an important role in cancer therapy. Recently it was reported that disease progression or increase of tumor volume occurred during the time interval between diagnosis and treatment.1, 2 This could lead to a less optimal radiation treatment and consequently have an impact on overall survival. Moreover, the increasing number of diagnostic procedures, aimed at obtaining more accurate information about the tumor extension and biology, as well as the use of more sophisticated but labor intense radiation techniques could prolong the time interval between clinical symptoms and the start of the treatment. However, the influence of new diagnostic procedures or the applied radiotherapy techniques on waiting times is not yet known. The investigators therefore want to investigate 1 time trends in the waiting time for NSCLC patients, 2 the correlation between waiting times and the use of more advanced diagnostic or therapeutic procedures, and 3 the correlation between waiting times and overall survival. 