Possiel Jacqueline, Ammon Hanne Elisabeth, Guhlich Manuel, Conradi Lena-Christin, Ghadimi Michael, Wolff Hendrik Andreas, Schirmer Markus Anton, Samel Stephan, Mügge Michael, Rieken Stefan, Leu Martin, Dröge Leif Hendrik
Department of Radiotherapy and Radiation Oncology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
Department of General, Visceral and Pediatric Surgery, University Medical Center Göttingen, 37075 Göttingen, Germany.
Cancers (Basel). 2021 May 21;13(11):2533. doi: 10.3390/cancers13112533.
Intensity-modulated radiotherapy (IMRT) is the standard of care in chemoradiotherapy (CRT) for anal cancer. Until now, only a limited number of studies have analyzed the results with VMAT (volumetric modulated arc therapy). We conducted a retrospective study on patients treated at our institution.
We included patients who received curative CRT for anal cancer. We compared VMAT-treated and 3DCRT (3D conformal radiotherapy)-treated patients. We analyzed toxicities (acute: CTCAE criteria; late: LENT/SOMA criteria), treatment compliance, overall survival, cancer-specific survival (CSS), distant control (DC), and locoregional control.
A total of 149 patients (3DCRT: = 87, VMAT: = 62) were included. The median follow-up was longer in 3DCRT-treated patients (3DCRT: 61.3 months; VMAT: 39.1 months; < 0.05). VMAT-treated patients had more G3 tumors (3DCRT: 12/87 (13.8%); VMAT: 18/62 (29.0%), < 0.001). VMAT reduced acute toxicities ≥grade 3 (3DCRT: = 48/87 (55.2%); VMAT: = 11/62 (17.7%), < 0.001). VMAT improved treatment compliance (less interruptions/delays) (3DCRT: 37/87, 42.5%; VMAT: 4/62, 6.5%; < 0.001), provided a shorter median overall treatment time (3DCRT: 41 days; VMAT: 38 days; = 0.02), and gave a higher median absolute 5-fluorouracil dose (3DCRT: 13,700 mg; VMAT: 14,400 mg; = 0.001). Finally, we found improved CSS ( = 0.02; 3DCRT: 81.9% at 3 years; VMAT: 94.1% at 3 years) and DC ( = 0.01; 3DCRT: 89.4% at 3 years; VMAT: 100.0% at 3 years) with VMAT.
Our study is the first to demonstrate improved treatment compliance and outcomes with VMAT for anal cancer. Previous studies have indicated that organs at risk sparing might be more improved with the use of VMAT vs. with conventional IMRT. Future studies should address whether these advantages lead to a further reduction in CRT-associated morbidity.
调强放疗（IMRT）是肛管癌放化疗（CRT）的标准治疗方法。到目前为止，仅有有限数量的研究分析了容积调强弧形放疗（VMAT）的治疗结果。我们对在本机构接受治疗的患者进行了一项回顾性研究。
我们纳入了接受根治性肛管癌CRT的患者。我们比较了接受VMAT治疗和3DCRT（三维适形放疗）治疗的患者。我们分析了毒性反应（急性：采用CTCAE标准；晚期：采用LENT/SOMA标准）、治疗依从性、总生存期、癌症特异性生存期（CSS）、远处控制（DC）和局部区域控制。
共纳入149例患者（3DCRT组：n = 87，VMAT组：n = 62）。3DCRT治疗的患者中位随访时间更长（3DCRT组：61.3个月；VMAT组：39.1个月；P < 0.05）。VMAT治疗的患者G3期肿瘤更多（3DCRT组：12/87（13.8%）；VMAT组：18/62（29.0%），P < 0.001）。VMAT降低了≥3级急性毒性反应（3DCRT组：n = 48/87（55.2%）；VMAT组：n = 11/62（17.7%），P < 0.001）。VMAT改善了治疗依从性（中断/延迟更少）（3DCRT组：37/87，42.5%；VMAT组：4/62，6.5%；P < 0.001），缩短了中位总治疗时间（3DCRT组：41天；VMAT组：38天；P = 0.02），并提高了中位5-氟尿嘧啶绝对剂量（3DCRT组：13,700 mg；VMAT组：14,400 mg；P = 0.001）。最后，我们发现VMAT改善了CSS（P = 0.02；3DCRT组：3年时为81.9%；VMAT组：3年时为94.1%）和DC（P = 0.01；3DCRT组：3年时为89.4%；VMAT组：3年时为100.0%）。
我们的研究首次证明了VMAT用于肛管癌可改善治疗依从性和治疗结果。先前的研究表明，与传统IMRT相比，使用VMAT可能更能改善危及器官的保护。未来的研究应探讨这些优势是否会进一步降低CRT相关的发病率。
