The Treatment Outcome and Radiation-Induced Toxicity for Patients with Head and Neck Carcinoma in the IMRT Era: A Systematic Review with Dosimetric and Clinical Parameters

A descriptive analysis was made in terms of the related radiation induced acute and late mucositis and xerostomia along with survival and tumor control rates (significance level at 0.016, bonferroni correction), for irradiation in head and neck carcinomas with either 2D Radiation Therapy (2DRT) and 3D conformal (3DCRT) or Intensity Modulated Radiation Therapy (IMRT). The mean score of grade > II xerostomia for IMRT versus 2-3D RT was 0.31 +/- 0.23 and 0.56 +/- 0.23, respectively (Mann Whitney, P < 0.001). The parotid-dose for IMRT versus 2-3D RT was 29.56 +/- 5.45 and 50.73 +/- 6.79, respectively (Mann Whitney, P = 0.016). The reported mean parotid-gland doses were significantly correlated with late xerostomia (spearman test, rho = 0.5013, P < 0.001). A trend was noted for the superiority of IMRT concerning the acute oral mucositis. The 3-year overall survival for either IMRT or 2-3DRT was 89.5% and 82.7%, respectively (P = 0.026, Kruskal-Wallis test). The mean 3-year locoregional control rate was 83.6% (range: 70-97%) and 74.4 (range: 61-82%), respectively (P = 0.025, Kruskal-Wallis). In conclusion, no significant differences in terms of locoregional control, overall survival and acutemucositis could be noted, while late xerostomia is definitely higher in 2-3D RT versus IMRT. Patients with head and neck carcinoma should be referred preferably to IMRT techniques.