胃肠道腺癌根治性术后外科伤口的^(68)Ga-FAPI-04和^(18)F-FDG摄取特征

Uptake characteristics of ^(68)Ga-FAPI-04 and ^(18)F-FDG in surgical wounds after radical surgery for gastrointestinal adenocarcinoma

目的探索胃肠道腺癌根治性术后消化道重建吻合口的^(68)Ga-成纤维细胞激活蛋白抑制剂(FAPIs)和^(18)F-FDG摄取特征及变化规律。方法前瞻性纳入2020年11月至2022年6月于空军军医大学第一附属医院行^(18)F-FDG PET/CT复查的胃癌或肠癌根治性术后患者43例,其中男28例、女15例,年龄28~79岁,于^(18)F-FDG PET/CT检查1周后行^(68)Ga-FAPI-04 PET/CT显像。在PET图像摄取最高层面勾画消化道重建吻合口及腹壁切口的ROI,计算SUV_(max)及靶本比(TBR)。采用χ^(2)检验、单因素方差分析、Kruskal-Wallis秩和检验(Bonferroni校正法)及Wilcoxon符号秩检验分析数据。结果共纳入外科伤口86例,胃-肠吻合口13例、食管-肠吻合口14例、肠-肠吻合口16例及腹壁切口43例。在^(68)Ga-FAPI-04 PET显像中,胃-肠吻合口SUV_(max)高于腹壁切口(调整后P=0.014),而TBR在各类外科伤口间的差异无统计学意义(H=3.88,P=0.275)。在^(18)F-FDG PET显像中,胃-肠吻合口、食管-肠吻合口及肠-肠吻合口SUV_(max)均高于腹壁切口(调整后均P<0.001),而TBR在各类外科伤口间的差异无统计学意义(H=3.02,P=0.388)。在^(68)Ga-FAPI-04 PET显像中,各类外科伤口的TBR随术后时间的推移均呈下降趋势,除肠-肠吻合口,各类外科伤口在<0.5年及≥1.5年组间TBR的差异均有统计学意义(调整后均P<0.05)。在^(18)F-FDG PET显像中,腹壁切口的TBR随术后时间的推移呈下降趋势,余外科伤口的TBR均未呈现下降趋势,且不同时间组间TBR的差异均无统计学意义(H值:0.53~2.75,P值:0.252~0.768)。对比2种PET显像,所有外科伤口在<0.5年及0.5~1.5年组内,^(68)Ga-FAPI-04 TBR均高于^(18)F-FDG TBR(z值:-3.17和-2.55,P值:0.002和0.011),而≥1.5年组内TBR趋于一致(z=-0.70,P=0.485)。结论消化道重建吻合口的^(18)F-FDG摄取在术后半年内就已降至较低水平且不随时间的推移产生显著变化,^(68)Ga-FAPIs摄取在术后1.5年内处于相对较高水平,但随时间的推移而降低,提示临床需注意鉴别诊断外科伤口炎性反应或纤维化引起的显像剂摄取与局部肿瘤复发。

Objective To explore the uptake characteristics and temporal changes of ^(68)Ga-fibroblast activation protein inhibitors(FAPIs)and ^(18)F-FDG in the anastomotic site of reconstructed digestive tracts after radical surgery for gastrointestinal adenocarcinoma.Methods A cohort of 43 patients(28 males,15 females;age range 28-79 years)who underwent radical surgery for gastrointestinal adenocarcinoma and underwent ^(18)F-FDG PET/CT follow-up between November 2020 and June 2022 in the First Affiliated Hospital of the Air Force Medical University was prospectively included.One week after the ^(18)F-FDG PET/CT examination,^(68)Ga-FAPI-04 PET/CT imaging was performed.ROIs were drawn on the PET images at the highest uptake level of anastomotic sites of reconstructed digestive tract and abdominal wall incisions,and SUV_(max) and target-to-background ratio(TBR)were determined.χ^(2) test,one-way analysis of variance,Kruskal-Wallis rank sum test(Bonferroni correction)and Wilcoxon signed-rank test were supplied.Results There were 86 surgical wounds(13 gastric-intestinal anastomotic sites,14 esophagus-intestinal anastomotic sites,16 intestinal-intestinal anastomotic sites,and 43 abdominal wall incisions)included.In ^(68)Ga-FAPI-04 PET imaging,SUV_(max) of gastric-intestinal anastomotic sites was higher than that of abdominal wall incisions,with a statistically significant difference(adjusted P=0.014).The TBR did not show statistically significant differences among different types of surgical wounds(H=3.88,P=0.275).In ^(18)F-FDG PET imaging,SUV_(max) of gastric-intestinal,esophagus-intestinal,and intestinal-intestinal anastomotic sites were all higher than that of abdominal wall incisions,with statistically significant differences(adjusted all P<0.001).There were no statistically significant differences in TBR among different types of surgical wounds(H=3.02,P=0.388).In ^(68)Ga-FAPI-04 PET imaging,the TBR of all types of anastomotic sites exhibited a decreasing trend with increasing postoperative time.Except for intestinal-intestinal anastomotic sites,the differences in TBR between<0.5-year and≥1.5-year groups were statistically significant for other types of surgical wounds(adjusted P<0.05).In ^(18)F-FDG PET imaging,the TBR of abdominal wall incisions showed a decreasing trend with increasing postoperative time.However,the TBR of other types of surgical wounds did not show a decreasing trend,and the differences in TBR among different time groups were not statistically significant(H values:0.53-2.75,P values:0.252-0.768).In comparing the two PET imaging agents,for all surgical wounds within the<0.5-year and 0.5-1.5-year groups,the ^(68)Ga-FAPI-04 TBR was consistently higher than the ^(18)F-FDG TBR(z values:-3.17 and-2.55,P values:0.002 and 0.011).However,in the≥1.5-year group,the TBR values tended to be consistent,and the differences were not statistically significant(z=-0.70,P=0.485).Conclusions The ^(18)F-FDG uptake in the anastomotic sites of reconstructed digestive tracts reaches a low level under half a year after surgery and does not significantly change over time,while the ^(68)Ga-FAPIs uptake remains relatively high within the first 1.5 years after surgery but decreases over time.These patterns suggest that clinical attention should be paid to the differential diagnosis of anastomotic inflammation or fibrosis,which resulting in agent uptake and local tumor recurrence.