Dosimetric comparison of field-in-field and intensity-modulated radiotherapy techniques in bilateral breast cancer radiotherapy

Abstract

Aim: This study aims to compare the dosimetric parameters, treatment efficiency, and organ-at-risk (OAR) sparing between field-in-field (FinF) and intensity-modulated radiotherapy (IMRT) techniques in the treatment of bilateral breast cancer. Method: Radiotherapy treatment plans were developed for 10 patients diagnosed with bilateral breast cancer using both FinF and IMRT techniques. Dosimetric parameters, including Dmax, V47.5, V46, D2, D50, and D98 for target volumes, were evaluated. Conformity index (CI) and homogeneity index (HI) were also assessed. Additionally, OAR doses were compared to determine the advantages and disadvantages of each technique. All plans were evaluated in accordance with international standards and quality control protocols. Results: Both techniques achieved clinically acceptable dose distributions. FinF plans demonstrated lower OAR doses and were more advantageous in terms of treatment time, number of fields, and segment count. Conversely, IMRT plans provided superior dose homogeneity and target coverage. Although IMRT required longer planning and treatment times due to higher segment numbers, OAR doses remained within acceptable limits and were consistent with the literature. Conclusion: The FinF technique remains a viable and efficient option in bilateral breast cancer radiotherapy, particularly in reducing OAR doses and treatment duration. However, IMRT offers better conformity and dose homogeneity, making it preferable when precise dose distribution is prioritized. Selection of the appropriate technique should be patient-specific, balancing clinical priorities and resource availability.

Amaç: Bu çalışmanın amacı, bilateral meme kanseri tedavisinde kullanılan alan içinde alan (FinF) ve yoğunluk ayarlı radyoterapi (YART/IMRT) tekniklerinin dozimetrik parametreler, tedavi etkinliği ve risk altındaki organların (RAO) korunması açısından karşılaştırılmasıdır.