Yoshio Kotaro, Nagasaka Hisako, Hisazumi Kento, Okawa Hiro, Tajiri Nobuhisa, Shiode Tsuyoki, Akaki Shiro, Kanazawa Susumu, Mitoma Tomohiro, Yano Yuri, Kobayashi Emiko, Horiguchi Ikuyo, Takata Masayo, Hongo Atsushi, Yonezawa Masaru, Nakanishi Yoshie
Department of Radiology, Kagawa Prefectural Central Hospital.
Department of Obstetrics and Gynecology, Kagawa Prefectural Central Hospital.
Acta Med Okayama. 2021 Feb;75(1):79-85. doi: 10.18926/AMO/61438.
The purposes of this retrospective study were to analyze local control of squamous cell carcinoma of the cervix treated with computed tomography (CT)-based image-guided brachytherapy (IGBT), as well as the factors affecting local control. A total of 39 patients were analyzed. The prescribed dose to the pelvis was 45-50 Gy with or without central shielding (CS). IGBT was delivered in 1-5 fractions. The total dose for high-risk clinical target volume (HR-CTV) was calculated as the biologically equivalent dose in 2-Gy fractions. The median follow-up period was 29.3 months. The 2-year overall survival and local control rates were 97% and 91%, respectively. In univariate analysis, the dose covering 90% of the HR-CTV (D90) and tumor size were found to be significant factors for local control. The cutoff values of tumor size and D90 for local control were 4.3 cm (area under the curve [AUC] 0.75) and 67.7 Gy (AUC 0.84) in the CS group and 5.3 cm (AUC 0.75) and 73.7 Gy (AUC 0.78) in the group without CS, respectively. However, though the local control of CT-based IGBT was favorable, the results suggested that the dose required for tumor control may differ depending on the presence of CS.
本回顾性研究的目的是分析基于计算机断层扫描（CT）的图像引导近距离放射治疗（IGBT）对子宫颈鳞状细胞癌的局部控制情况，以及影响局部控制的因素。共分析了39例患者。盆腔的处方剂量为45-50 Gy，有或无中央屏蔽（CS）。IGBT分1-5次给予。高危临床靶区（HR-CTV）的总剂量按2-Gy分次的生物等效剂量计算。中位随访期为29.3个月。2年总生存率和局部控制率分别为97%和91%。单因素分析发现，覆盖90% HR-CTV的剂量（D90）和肿瘤大小是局部控制的重要因素。CS组局部控制的肿瘤大小和D90的截断值分别为4.3 cm（曲线下面积[AUC] 0.75）和67.7 Gy（AUC 0.84），无CS组分别为5.3 cm（AUC 0.75）和73.7 Gy（AUC 0.78）。然而，尽管基于CT的IGBT局部控制效果良好，但结果表明，根据CS的存在情况，肿瘤控制所需的剂量可能有所不同。
