KEY TAKEAWAYS
- The study aimed to compare the efficacy of ssIMRT and dIMRT for different treatment sites.
- The results concluded that dIMRT offers better coverage, homogeneity, and faster delivery compared to ssIMRT.
Nabila Es Fodil aimed to assess the efficacy of static (ssIMRT) and dynamic (dIMRT) intensity-modulated radiotherapy for head and neck cancer and other treatment sites.
The study used the treatment planning system (TPS) to create optimal plans for 27 patients inlcuding 9 with head and neck cancer, 9 with prostate cancer, and 9 with cervical cancer. Prescribed doses were 7000 cGy/33 fractions for nasopharynx, 7425 cGy/33 fractions for prostate, and 5000 cGy/25 fractions for cervix cases, applied to both ssIMRT and dIMRT techniques.
Plans were developed with the Monaco TPS using a 6MV photon beam and 9 equidistant fields. Evaluation criteria included dose-volume histogram analysis, dose homogeneity index, conformity index, radiation delivery time, and monitor unit requirements.
All plans were optimized to ensure that 98% of the planning target volume (PTV) received at least 95% of the prescribed dose while meeting planning objectives for organs at risk. The dIMRT plans demonstrated superior conformity (CI= 0.85 ± 0.05) compared to ssIMRT plans (CI= 0.79 ± 0.08), with statistically significant differences (P< 0.01).
Inhomogeneity within the PTV was significantly greater in ssIMRT plans (HI= 0.10 ± 0.02) than in dIMRT plans (HI= 0.09 ± 0.01), with a significant difference (P< 0.01). Delivery time per fraction was significantly lower for dIMRT compared to ssIMRT (P< 0.01). Additionally, dIMRT plans required a higher mean monitor unit value (1335.4 ± 172.2) compared to ssIMRT plans (974.4 ± 133.6), with a significant difference (P< 0.001).
The study concluded that dIMRT offers better target coverage, homogeneity, and conformity, while also reducing treatment delivery time compared to ssIMRT.
No funding information was available.
Source: https://pubmed.ncbi.nlm.nih.gov/39068581/
Fodil NE, Abdelhakem MM, Yahia GA, et al. (2024). “Evaluation of Dynamic Multi-Leaf Collimator (MLC) versus Fixed MLC for Intensity Modulated Radiotherapy (IMRT) Using the Agility 160-Leaf Collimator.” Asian Pac J Cancer Prev. 2024 Jul 1;25(7):2467-2474. doi: 10.31557/APJCP.2024.25.7.2467. PMID: 39068581.
