Department of Medical Oncology, Yuzuncu Yil University Medical School, 65030, Van, Turkey.
Department of Medical Oncology, University of Health Sciences, Van Training and Research Hospital, Van, Turkey.
J Gastrointest Cancer. 2022 Jun;53(2):341-347. doi: 10.1007/s12029-021-00608-y. Epub 2021 Mar 2.
To investigate the prognostic effects of baseline volumetric PET/CT parameters including the maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and tumor lesion glycolysis (TLG) on treatment response and prognosis in locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (NACRT).
Between 2015 and 2018, 51 patients with LARC treated with NACRT followed by surgery were included in this retrospective study. Patients were divided into 2 groups by tumor regression grade (TRG) as follows: group I = TRG 1 (no detectable cancer cells) + TRG 2 (single cells and/or small groups of cancer cells) and group II = TRG3 (residual tumor outgrown by fibrosis) + TRG 4 (remarkable fibrosis outgrown by tumor cells) + TRG 5 (no fibrosis with extensive residual cancer).
Of the 51 patients, 34 (66.7%) were male. The median age was 55 (range, 37-78) years. According to TRG status, 14 (27.4%) patients were in group I and 37 (72.6%) patients were in group II. The area under the curve (95% CI) was 0.749 (0.593-0.905) in the ROC curve plotted for MTV. The cut-off value for MTV was 12, with 70% sensitivity and 65% specificity. MTV was ≥ 12 in 32 (62.8%) patients. MTV and TLG values were significantly different between groups I and II, whereas there was no significant difference between the groups in terms of SUVmax values (p = 0.006, p = 0.033, and p = 0.673, respectively). The disease-free survival was not reached in patients with MTV < 12 vs. 20 months in those with MTV ≥ 12 (p = 0.323). In multivariate analysis, MTV (OR, 95% Cl, 5.00 [1.17-21.383]) was found to be the factor that affected pathological complete response.
In LARC treated with NACRT, MTV prior to treatment can help predict the response to treatment.
研究基线容积式 PET/CT 参数（最大标准摄取值 [SUVmax]、代谢肿瘤体积 [MTV] 和肿瘤病变糖酵解 [TLG]）对接受新辅助放化疗（NACRT）治疗的局部晚期直肠癌（LARC）治疗反应和预后的预测作用。
在 2015 年至 2018 年间，本回顾性研究纳入了 51 例接受 NACRT 治疗后行手术的 LARC 患者。根据肿瘤消退分级（TRG）将患者分为 2 组：组 I = TRG1（无检测到癌细胞）+TRG2（单个细胞和/或少量癌细胞）和组 II = TRG3（纤维化中残留肿瘤）+TRG4（肿瘤细胞中显著纤维化）+TRG5（无纤维化且广泛残留肿瘤）。
51 例患者中，34 例（66.7%）为男性。中位年龄为 55 岁（范围，37-78 岁）。根据 TRG 状态，14 例（27.4%）患者为组 I，37 例（72.6%）患者为组 II。MTV 绘制的 ROC 曲线下面积（95%CI）为 0.749（0.593-0.905）。MTV 的截断值为 12，具有 70%的敏感性和 65%的特异性。32 例（62.8%）患者的 MTV 值≥12。组 I 和组 II 之间 MTV 和 TLG 值差异有统计学意义，而两组间 SUVmax 值差异无统计学意义（p=0.006、p=0.033 和 p=0.673）。MTV<12 的患者无疾病生存时间未达到，而 MTV≥12 的患者为 20 个月（p=0.323）。多因素分析发现，MTV（OR，95%Cl，5.00[1.17-21.383]）是影响病理完全缓解的因素。
在接受 NACRT 治疗的 LARC 中，治疗前的 MTV 有助于预测治疗反应。
