Three-dimensional conformal radiotherapy for lung cancer: promises and pitfalls.

Lung cancer represents a major source of morbidity and mortality. Despite recent advances, long-term survival remains elusive in most patients with locally advanced cancer. A substantial proportion of these patients experience a relapse at the original site of disease within the thorax, making radiotherapy an important component of treatment. Of several approaches investigated to improve the therapeutic ratio in radiotherapy, three-dimensional conformal radiotherapy holds the most promise, primarily because it allows higher doses to be delivered to the target by improved shaping of radiation portals and conformal avoidance of normal structures. The rationale and evolution of this technology and its potential pitfalls are presented in this review.