The Effectiveness of Intensity Modulated Radiation Therapy versus Three-Dimensional Radiation Therapy in Prostate Cancer: A Meta-Analysis of the Literatures

Abstract

Background and purpose: Intensity modulated radiation therapy (IMRT) can deliver higher doses with less damage of healthy tissues compared with three-dimensional radiation therapy (3DCRT). However, for the scenarios with better clinical outcomes for IMRT than 3DCRT in prostate cancer, the results remain ambiguous. We performed a meta-analysis to assess whether IMRT can provide better clinical outcomes in comparison with 3DCRT in patients diagnosed with prostate cancer.

Materials and methods: We conducted a meta-analysis of 23 studies (n = 9556) comparing the clinical outcomes, including gastrointestinal (GI) toxicity, genitourinary (GU) toxicity, biochemical controland overall survival (OS).

Results: IMRT was significantly associated with decreased 2-4 grade acute GI toxicity [risk ratio (RR) = 0.59 (95% confidence interval (CI), 0.44, 0.78)], late GI toxicity [RR = 0.54, 95%CI (0.38, 0.78)], late rectal bleeding [RR = 0.48, 95%CI (0.27, 0.85)], and achieved better biochemical control[RR = 1.17, 95%CI (1.08, 1.27)] in comparison with 3DCRT. IMRT and 3DCRT remain the same in regard of grade 2-4 acute rectal toxicity [RR = 1.03, 95%CI (0.45, 2.36)], late GU toxicity [RR = 1.03, 95%CI (0.82, 1.30)] and overall survival [RR = 1.07, 95%CI (0.96, 1.19)], while IMRT slightly increased the morbidity of grade 2-4 acute GU toxicity [RR = 1.08, 95%CI (1.00, 1.17)].

Conclusions: Although some bias cannot be ignored, IMRT appears to be a better choice for the treatment of prostate cancer when compared with 3DCRT.

Fig 1. Flow chart of the literature search and selection of included studies.

Fig 2. Forrest plots of RRs for IMRT versus 3DCRT about the grade 2–4 acute toxicity and late toxicity.

(A) acute GI toxicity, (B) acute GU toxicity and (C) acute rectal toxicity, (D) late GI toxicity, (E) late GU toxicity and (F) late rectal bleeding.

Fig 3. Forrest plots of RRs for IMRT versus 3DCRT about the survival outcomes.

(A) Biochemical control, (B) OS.

Fig 4. Funnel graph for assessing the potential publication bias in the studies comparing IMRT and 3DCRT in patients diagnosed with prostate cancer.

(A) acute GI toxicity, (B) acute GU toxicity, (C) acute rectal toxicity, (D) late GI toxicity, (E) late GU toxicity, (F) late rectal bleeding, (G)Biochemical control, (H) OS.