Table 1. Potential advantages and pitfalls of intensity-modulated radiotherapy (IMRT) and image-guided radiotherapy (IGRT) compared to 3-dimentional conformal radiotherapy (3-D CRT).

	IMRT, IGRT	3-D CRT
Advantages:	Sparing of normal organs because of rapid dose fall	No sparing
	Tumor dose escalation possible because of different dose levels within the target volume	No dose escalation
	Visualization of tumor shrinkage feasible for IGRT allowing re-planning during radiotherapy	No visualization
Pitfalls:	Marginal miss if tumor not properly contoured leading to local recurrences.	Unlikely