Background: This review aims to assess the effectiveness of Intensity-Modulated Radiation Therapy (IMRT) in the treatment of various types of cancer, focusing on its clinical outcomes, toxicity profiles, and comparison with other radiation techniques such as ۳D Conformal Radiation Therapy (۳DCRT) and conventional ۲D radiation therapy (۲D-RT). Materials and Methods: A systematic review and meta-analysis were conducted, evaluating multiple studies that compared IMRT with ۳DCRT or ۲D-RT in patients diagnosed with different cancers, including prostate, cervical, and breast cancer. The primary outcomes were the incidence of acute and chronic toxicities (gastrointestinal and genitourinary), biochemical control, and overall survival rates. Secondary outcomes included quality of life and cost-effectiveness. Statistical analysis was performed using risk ratios and confidence intervals for comparing clinical outcomes across treatment modalities. Results: IMRT was associated with significant improvements in clinical outcomes compared to ۲D-RT and ۳DCRT. Notably, it resulted in lower incidence rates of acute and late gastrointestinal and genitourinary toxicities. Studies on prostate cancer showed that IMRT reduced acute gastrointestinal toxicity and improved biochemical control. In cervical cancer, IMRT offered better targeting, reducing damage to surrounding tissues, although challenges related to tumor motion and accurate boundary demarcation were noted. Additionally, IMRT has shown a favorable cost-effectiveness ratio in the treatment of localized prostate cancer compared to ۳DCRT. Conclusion: IMRT offers significant clinical benefits, particularly in reducing treatment-related toxicities and improving tumor targeting. This technology provides a more precise and safer treatment option compared to traditional radiation techniques, although it may come with higher upfront costs. Given its effectiveness, IMRT is recommended for various cancer types, though further studies are needed to address challenges such as organ motion and optimal imaging strategies. IMRT has shown notable benefits in clinical oncology by improving the targeting of tumors while protecting surrounding healthy tissues. Studies specifically highlight its effectiveness in reducing gastrointestinal and genitourinary toxicity in cancers such as prostate and cervical cancer.
