The effectiveness of intensity-modulated radiation therapy versus 2D-RT for the treatment of nasopharyngeal carcinoma: A systematic review and meta-analysis

by Taifeng Du, Jiefeng Xiao, Zhaolong Qiu, Kusheng Wu

At present, the management of nasopharyngeal carcinoma (NPC) is mainly based on radiotherapy, but there are many radiation delivery techniques such as intensity-modulated radiotherapy (IMRT) and 2-dimensional radiotherapy (2D-RT).

We searched all the eligible studies through the PubMed, Cochrane Library, Medline, and Embase. The endpoint events in meta-analysis were overall survival (OS), tumor local control including local-regional free survival (LRFS), progression-free survival (PFS), and distant metastasis-free survival (DMFS), and late toxicities.

A total of ten publications met the criteria and were identified through searches of the databases and references. We included 13304 patients in the meta-analysis, of whom 5212 received IMRT and 8092 were allocated to 2D-RT alone group. Compared with 2D-RT treatment, the IMRT group was associated with a better 5-year OS (OR = 1.70; 95% CI = 1.36–2.12), LRFS (OR = 2.08; 95% CI = 1.82–2.37), and PFS (OR = 1.40; 95% CI = 1.26–1.56). Additionally, the incidence of late toxicities such as late xerostomia (OR = 0.21; 95% CI = 0.09–0.51), trismus (OR = 0.16; 95% CI = 0.04–0.60), and temporal lobe neuropathy (TLN) (OR = 0.40; 95% CI = 0.24–0.67) for NPC patients in IMRT group were significantly lower than 2D-RT.

The meta-analysis demonstrates that IMRT provides improved long-term tumor overall survival and local control including LRFS and PFS. Additionally, IMRT yields a lower incidence of late toxicities induced by irradiation in NPC patients. Compared to 2D-RT, IMRT may be an effective treatment for patients with NPC. Further intensive studies should be pursued to examine the association.