Study of 3-Dimensional Conformal Radiotherapy (3D-CRT) Versus Intensity Modulated Radiotherapy (IMRT) for Head and Neck Squamous Cell Carcinoma (HNSCC)

Head \& Neck squamous cell carcinomas are the commonest cancers afflicting the developing countries. Traditionally surgery or radiotherapy alone in the early stages and surgery with postoperative radiotherapy in advanced stages have been the mainstay of treatment. Of late there has been a paradigm shift in the management of these cancers, particularly those of the oropharynx and laryngopharynx, where chemoradiation has been advocated as part of organ preservation protocol with good outcomes. Conventional radiotherapy involves the use of 2 or 3 field technique with or without compensators to encompass the volume at risk to radical doses of 66-70 Gy typically needed to sterilize gross disease. This strategy however is associated with considerable acute morbidity (mucositis, dysphagia, dermatitis) and debilitating late toxicity (xerostomia). Three dimensional conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) have the potential to improve the dose distribution, with increased doses to the target volumes and reduced doses to surrounding normal structures, thereby improving the therapeutic ratio.