Tekiki Nouha, Kuroda Masahiro, Ishizaka Hinata, Khasawneh Abdullah, Barham Majd, Hamada Kentaro, Konishi Kohei, Sugimoto Kohei, Katsui Kuniaki, Sugiyama Soichi, Watanabe Kenta, Yoshio Kotaro, Katayama Norihisa, Ogata Takeshi, Ihara Hiroki, Kanazawa Susumu, Asaumi Junichi
Department of Oral and Maxillofacial Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan.
Department of Radiological Technology, Graduate School of Health Sciences, Okayama University, Okayama 700-8558, Japan.
Mol Clin Oncol. 2021 Sep;15(3):193. doi: 10.3892/mco.2021.2355. Epub 2021 Jul 21.
The usefulness of the field-in-field with two reference points (FIF w/ 2RP) method, in which the dose reference points are set simultaneously at two positions in the irradiation field and the high-dose range is completely eliminated, was examined in the present study with the aim of decreasing acute skin toxicity in adjuvant breast radiotherapy (RT). A total of 573 patients with breast cancer who underwent postoperative whole breast RT were classified into 178 cases with wedge (W) method, 142 cases with field-in-field without 2 reference points (FIF w/o 2RP) method and 253 cases with FIF w/ 2RP method. Using the FIF w/ 2RP method, the high-dose range was the lowest among the three irradiation methods. The planning target volume (PTV) V105% and the breast PTV for evaluation (BPe) V105% decreased to 0.09 and 0.10%, respectively. The FIF w/ 2RP method vs. the FIF w/o 2RP method had a strong association (η) with PTV V105% (η=0.79; P<0.001) and BPe V105% (η=0.76; P<0.001). The FIF w/ 2RP method had a significant impact on lowering the skin toxicity grade in weeks 3 and 4, and increasing the occurrence of skin toxicity grade 0. The FIF w/ 2RP method vs. the W method had a moderate association with skin toxicity grade at week 3 (η=0.49; P<0.001). Using the FIF w/ 2RP method, the high-dose range V105% of the target decreased to 0%, and skin adverse events were decreased in conjunction. For patients with early-stage breast cancer, particularly patients with relatively small-sized breasts, the FIF w/ 2RP method may be an optimal irradiation method.
本研究对野中野双参考点（FIF w/ 2RP）方法的有效性进行了检验，该方法是在照射野中的两个位置同时设置剂量参考点，并完全消除高剂量范围，目的是降低辅助性乳腺癌放疗（RT）中的急性皮肤毒性。共有573例接受术后全乳放疗的乳腺癌患者被分为178例采用楔形（W）方法、142例采用无双参考点野中野（FIF w/o 2RP）方法和253例采用FIF w/ 2RP方法。采用FIF w/ 2RP方法时，高剂量范围在三种照射方法中最低。计划靶体积（PTV）的V105%和用于评估的乳腺PTV（BPe）的V105%分别降至0.09%和0.10%。FIF w/ 2RP方法与FIF w/o 2RP方法在PTV的V105%（η=0.79；P<0.001）和BPe的V105%（η=0.76；P<0.001）方面有很强的相关性。FIF w/ 2RP方法对降低第3周和第4周的皮肤毒性分级以及增加0级皮肤毒性的发生率有显著影响。FIF w/ 2RP方法与W方法在第3周时与皮肤毒性分级有中等相关性（η=0.49；P<0.001）。采用FIF w/ 2RP方法时，靶区的高剂量范围V105%降至0%，同时皮肤不良事件减少。对于早期乳腺癌患者，尤其是乳房相对较小的患者，FIF w/ 2RP方法可能是一种最佳的照射方法。
