Abstract：
This study aimed to evaluate the prognostic value of 18F-FDG PET/CT qualitative assessment in terms of recurrence-free survival (RFS), colostomy-free survival (CFS), and overall survival (OS) after radiation therapy (RT) of squamous cell carcinoma of the anus (SCCA). Secondary objectives were to evaluate the prognostic value of baseline and posttherapeutic quantitative 18F-FDG PET/CT parameters in terms of RFS, CFS, and OS. Methods: We included all consecutive patients from the French multicentric cohort FFCD-ANABASE who had undergone 18F-FDG PET/CT at baseline and 4-6 mo after RT or chemoradiotherapy for a localized SCCA. Qualitative assessments separated patients with complete metabolic response (CMR) and non-CMR. Quantitative parameters were measured on baseline and posttreatment 18F-FDG PET/CT. RFS, CFS, and OS were analyzed using the Kaplan-Meier method. Associations among qualitative assessments, quantitative parameters, and RFS, CFS, and OS were analyzed using univariate and multivariate Cox regression. Results: Among 1,015 patients treated between January 2015 and April 2020, 388 patients (300 women and 88 men) from 36 centers had undergone 18F-FDG PET/CT at diagnosis and after treatment. The median age was 65 y (range, 32-90 y); 147 patients (37.9%) had an early-stage tumor and 241 patients (62.1%) had a locally advanced-stage tumor; 59 patients (15.2%) received RT, and 329 (84.8%) received chemoradiotherapy. The median follow-up was 35.5 mo (95% CI, 32.8-36.6 mo). Patients with CMR had better 3-y RFS, CFS, and OS, at 84.2% (95% CI, 77.8%-88.9%), 84.7% (95% CI, 77.2%-89.3%), and 88.6% (95% CI, 82.5%-92.7%), respectively, than did non-CMR patients, at 42.1% (95% CI, 33.4%-50.6%), 47.9% (95% CI, 38.1%-56.8%), and 63.5 (95% CI, 53.2%-72.1%), respectively (P < 0.0001). Quantitative parameters were available for 154 patients from 3 centers. The following parameters were statistically significantly associated with 3-y RFS: baseline SUVmax (primitive tumor [T]) (hazard ratio [HR], 1.05 [95% CI, 1.01-1.1; P = 0.018]), SUVpeak (T) (HR, 1.09 [95% CI, 1.02-1.15; P = 0.007]), MTV 41% (T) (HR, 1.02 [95% CI, 1-1.03; P = 0.023]), MTV 41% (lymph node [N]) (HR, 1.06 [95% CI, 1.03-1.1; P < 0.001]), MTV 41% (T + N) (HR, 1.02 [95% CI, 1-1.03; P = 0.005]), and posttreatment SUVmax (HR, 1.21 [95% CI, 1.09-1.34; P < 0.001]). Conclusion: Treatment response assessed by 18F-FDG PET/CT after RT for SCCA has a significant prognostic value.18F-FDG PET/CT could be useful for adapting follow-up, especially for patients with locally advanced-stage tumors. Quantitative parameters could permit identification of patients with a worse prognosis but should be evaluated in further trials.
摘要：
这项研究旨在评估18F-FDGPET/CT定性评估在无复发生存期（RFS）方面的预后价值。无结肠造口生存（CFS），肛门鳞状细胞癌（SCCA）放射治疗（RT）后的总生存期（OS）。次要目标是根据RFS评估基线和治疗后定量18F-FDGPET/CT参数的预后价值，CFS,和OS。方法：我们纳入了来自法国多中心队列FFCD-ANABASE的所有连续患者，这些患者在基线和RT或局部SCCA放化疗后4-6个月接受了18F-FDGPET/CT。定性评估将具有完全代谢反应（CMR）和非CMR的患者分开。在基线和治疗后18F-FDGPET/CT测量定量参数。RFS,CFS,和OS使用Kaplan-Meier方法进行分析。定性评估之间的关联，定量参数，和RFS,CFS,和OS采用单因素和多因素Cox回归分析。结果：在2015年1月至2020年4月期间接受治疗的1,015例患者中，来自36个中心的388例患者（300名女性和88名男性）在诊断和治疗后接受了18F-FDGPET/CT检查。中位年龄为65岁(范围，32-90岁）；147例患者（37.9%）有早期肿瘤，241例患者（62.1%）有局部晚期肿瘤；59例患者（15.2%）接受RT，329例(84.8%)接受放化疗。中位随访时间为35.5个月（95%CI，32.8-36.6个月）。CMR患者有更好的3-yRFS，CFS,和操作系统，84.2%（95%CI，77.8%-88.9%），84.7%（95%CI，77.2%-89.3%），和88.6%（95%CI，82.5%-92.7%），分别,与非CMR患者相比，42.1%（95%CI，33.4%-50.6%），47.9%（95%CI，38.1%-56.8%），和63.5（95%CI，53.2%-72.1%），分别为(P<0.0001)。来自3个中心的154名患者的定量参数可用。以下参数与3-yRFS有统计学意义：基线SUVmax（原始肿瘤[T]）（风险比[HR]，1.05[95%CI，1.01-1.1；P=0.018])，SUVpeak(T)(HR,1.09[95%CI，1.02-1.15；P=0.007])，MTV41%（T）（HR，1.02[95%CI，1-1.03；P=0.023])，MTV41%（淋巴结[N]）（HR，1.06[95%CI，1.03-1.1；P<0.001]），MTV41%（T+N）（HR，1.02[95%CI，1-1.03；P=0.005])，和治疗后SUVmax(HR，1.21[95%CI，1.09-1.34；P<0.001]）。结论:18F-FDGPET/CT评估SCCA放疗后的治疗反应具有重要的预后价值。18F-FDGPET/CT可用于适应随访。尤其是局部晚期肿瘤患者。定量参数可以识别预后较差的患者，但应在进一步的试验中进行评估。
