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Introduction: Due to the limited target volume and irregular body surface, irradiating the chest wall (CW) and lymphatic nodes is more challenging. IMRT and VMAT (volumetric modulated arc therapy) are two treatment delivery techniques that help to improve dose coverage and homogeneity while reducing irradiation to the heart and ipsilateral (I/L) lung. The use of a hybrid treatment planning approach for the ca-breast will impact the treatment plan. The hybrid planning system must be reviewed and compared to alternative treatment options for ca-breast cancer. Material and Methods: For 10 patients undergoing left-sided breast chest wall irradiation, the 3 distinct planning techniques (FiF [Field-in-field], IMRT, and Hybrid IMRT) were evaluated. A prescription dose of 40 Gy in 15 fractions was used for the planned target volume (PTV). To compare plans, dose-volume histograms (DVHs) were assessed for PTV and organs at risk. Results: D95% of PTV was 37.10 ± 0.48 Gy in FiF, but considerably raised to 39.32 ± 0.34 Gy and 38.39 ± 0.29 Gy in IMRT (p=0.01) and Hybrid IMRT (p=0.01).When compared to IMRT (0.981 ± 0.014) and Hybrid IMRT (0.970 ± 0.013) FiF plans have the lowest CI value of 0.931 ± 0.026. IMRT plans (0.087 ± 0.021) were found to be more homogeneous than other 2 planning techniques (0.111 ± 0.013 [FiF, p=0.016], 0.107 ± 0.021[hybrid IMRT, p=0.056]). Conclusion: Hybrid IMRT treatment plans for the ca-breast are recommended because they provide superior and similar PTV dose coverage and OAR sparing compared to FiF and IMRT plans. Hybrid IMRT plans feature lower MU and BOT, as well as a smaller low dose volume in comparison to IMRT.

A new planning method for Craniospinal Irradiation by Eclipse treatment planning system using Field alignment, Field-in-Field technique was developed. Advantage of this planning method was also studied retrospectively for previously treated five patients of medulloblastoma with variable spine length. Plan consists of half beam blocked parallel opposed cranium, and a single posterior cervicospine field was created by sharing the same isocenter, which obviates divergence matching. Further, a single symmetrical field was created to treat remaining Lumbosacral spine. Matching between a inferior diverging edge of cervicospine field and superior diverging edge of a Lumbosacral field was done using the field alignment option. ′Field alignment′ is specific option in the Eclipse Treatment Planning System, which automatically matches the field edge divergence as per field alignment rule. Multiple segments were applied in both the spine field to manage with hot and cold spots created by varying depth of spinal cord. Plan becomes fully computerized using this field alignment option and multiple segments. Plan evaluation and calculated mean modified Homogeneity Index (1.04 and 0.1) ensured that dose to target volume is homogeneous and critical organ doses were within tolerance. Dose variation at the spinal field junction was verified using ionization chamber array (I′MatriXX) for matched, overlapped and gap junction spine fields; the delivered dose distribution confirmed the ideal clinical match, over exposure and under exposure at the junction, respectively. This method is simple to plan, executable in Record and Verify mode and can be adopted for various length of spinal cord with only two isocenter in shorter treatment time.