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Abstract: These last years, the new irradiation techniques as the conformal 3D radiotherapy and the IMRT are strongly correlated with the technological developments in radiotherapy. The rigorous definition of the target volume and the organs at risk required by these irradiation techniques, imposed the development of various image guided patient positioning and target tracking techniques. The availability of these imaging systems inside the treatment room has lead to the exploration of performing real-time adaptive radiation therapy. In this paper we present the different image guided radiotherapy (IGRT) techniques and the adaptive radiotherapy (ART) approaches. IGRT developments are focused in the following areas: 1) biological imaging for better definition of tumor volume; 2) 4D imaging for modeling the intra-fraction organ motion; 3) on-board imaging system or imaging devices registered to the treatment machines for inter-fraction patient localization; and 4) treatment planning and delivery schemes incorporating the information derived from the new imaging techniques. As this paper is included in the “Cancer–Radiotherapie” special volume dedicated to the lung cancers, in the description of the different IGRT techniques we try to present the lung tumors applications when this is possible. [Copyright &y& Elsevier]

Abstract: This paper focuses on stage I, II and IIIA non-small cell lung cancer treatable with local treatment. It addresses five questions raised by strategies combining local treatments with chemotherapy. Even if chemotherapy increases resectability of stage III disease, the chemotherapy-surgery combination has not been demonstrated to increase survival compared to the standard chemo-radiation treatment. The results of the study by Van Meerbeeck do not support this hypothesis. Does surgery, added to chemo-radiotherapy, improve the outcome in stage IIIAN2 disease? This was the question addressed by the study by K. Albain. There is probably not clear cut answer. However, the trimodality strategy might be interesting in patients undergoing a lobectomy and might have a negative impact when a pneumonectomy has been performed. In patients with a non resectable/inoperable cancer treated with standard chemoradiation, the concomitant strategy has been shown to be superior to sequential treatment. However, due to acute toxicity, it should be delivered to selected patients, who still need to be better defined. The chemotherapy-surgery combination is becoming standard (in stage II disease) and most cooperative groups will probably stand in favour of it in 2006. The best respective timing for chemotherapy and surgery is still debated. There are many advantages in favour of preoperative chemotherapy, including better feasibility and the higher proportion of patients who can benefit. However, there is no statistically reliable demonstration of such superiority. [Copyright &y& Elsevier]

The conformal radiotherapy approach, three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT), is based on modern imaging modalities, efficient 3D treatment planning systems, sophisticated immobilization devices and demanding quality assurance and treatment verification. The main goal of conformal radiotherapy is to ensure a high dose distribution tailored to the limits of the target volume while reducing exposure of healthy tissues. These techniques would then allow a further dose escalation increasing local control and survival. Non-small cell lung cancer (NSCLC) is one of the most difficult malignant tumors to be treated. It combines geometrical difficulties due to respiratory motion, and number of low tolerance neighboring organs, and dosimetric difficulties because of the presence of huge inhomogeneities. This localization is an attractive and ambitious example for the evaluation of new techniques. However, the published clinical reports in the last years described very heterogeneous techniques and, in the absence of prospective randomized trials, it is somewhat difficult at present to evaluate the real benefits drawn from those conformal radiotherapy techniques. After reviewing the rationale for 3DCRT for NSCLC, this paper will describe the main studies of 3DCRT, in order to evaluate its impact on lung cancer treatment. Then, the current state-of-the-art of IMRT and the last technical and therapeutic innovations in NSCLC will be discussed. [Copyright &y& Elsevier]