Wang Wei-Shu, Lin Jen-Kou, Lin Tzu-Chen, Chiou Tzeon-Jye, Liu Jin-Hwang, Yen Chueh-Chuan, Chen Wei-Shone, Jiang Jeng-Kae, Yang Shung-Haur, Wang Huann-Sheng, Chen Po-Min
Department of Medicine, Division of Medical Oncology, Veterans General Hospital, Taipei, Taiwan.
Hepatogastroenterology. 2002 Mar-Apr;49(44):388-92.
BACKGROUND/AIMS: The assessment of response to chemotherapy of solid tumors is generally made by measurement of tumors visualized by imaging, commonly computed tomography scanning. However, response assessment based on imaging is not always feasible because patients often have disease not measurable by imaging study, such as diffuse peritoneal dissemination. Furthermore, response assessment by imaging is expensive and time consuming. This study was carried out in an effort to evaluate the correlation between serial change on imaging and on CEA (carcinoembryonic antigen) levels for assessing chemotherapeutic response of patients with metastatic colorectal cancer.
Between May 1998 and August 1999, a total of 40 patients with metastatic colorectal carcinoma were enrolled in this study. All the patients had to have measurable lesions. Oral tegafur-uracil 300 mg/m2/day and folinic acid 60 mg/day were administered concurrently for four weeks, repeated every five weeks, as the first-line treatment. Tumor marker CEA was examined before and during the whole course of treatment. Response based on CEA assessment was defined as a more-than 50% drop in serum CEA level for more than four weeks. The correlation between serial change on CEA and on imaging for assessing chemotherapeutic response was evaluated.
Forty patients received a total of 318 courses of treatment and a response rate of 32.5% (95% confidence interval, 18.0% to 47.0%), including five complete responses and eight partial responses, was achieved by imaging studies. The pretreatment CEA levels were elevated beyond the normal cut-off value in 34 (85%) patients. The response rate evaluated by CEA assessment was 42.5% (17/40). Nine responders (22.5%) based on CEA had no remission on imaging. Agreement in assessment by imaging study and by CEA was observed in 20 patients (50%), including eight responders, five stable diseases, and seven progressive diseases. The sensitivity of falling CEA levels in the prediction of true responders on imaging was 62%. The sensitivity of elevated CEA levels for the prediction of progressive disease was 70%. Concerning the diagnostic accuracy, change in CEA levels in the prediction of true responders and progressive disease on imaging were 65% and 85%, respectively. On a follow-up of 24 months, patients with remarkable falling CEA levels survived significantly longer than non-responders (P = 0.0184, log-rank test).
The measurement of CEA levels might be useful in monitoring chemotherapeutic response and in predicting the prognosis of patients with metastatic colorectal cancer. Serum CEA level may be used as a means of monitoring chemotherapeutic response when imaging study is unsuitable for assessing the response in clinical practice.
背景/目的：实体瘤化疗反应的评估通常通过对影像学检查（通常是计算机断层扫描）显示的肿瘤进行测量来进行。然而，基于影像学的反应评估并不总是可行的，因为患者常常存在影像学检查无法测量的疾病，如弥漫性腹膜播散。此外，影像学反应评估成本高且耗时。本研究旨在评估影像学连续变化与癌胚抗原（CEA）水平变化之间的相关性，以评估转移性结直肠癌患者的化疗反应。
1998年5月至1999年8月，共有40例转移性结直肠癌患者纳入本研究。所有患者均须有可测量病灶。口服替加氟-尿嘧啶300mg/m²/天和亚叶酸60mg/天，同时给药4周，每5周重复一次，作为一线治疗。在治疗全过程之前及期间检测肿瘤标志物CEA。基于CEA评估的反应定义为血清CEA水平下降超过50%且持续超过4周。评估了CEA连续变化与影像学用于评估化疗反应之间的相关性。
40例患者共接受318个疗程的治疗，影像学检查的反应率为32.5%（95%置信区间，18.0%至47.0%），包括5例完全缓解和8例部分缓解。34例（85%）患者治疗前CEA水平高于正常临界值。基于CEA评估的反应率为42.5%（17/40）。基于CEA的9例反应者（22.5%）影像学检查未缓解。20例患者（50%）影像学检查与CEA评估结果一致，包括8例反应者、5例病情稳定者和7例病情进展者。CEA水平下降在预测影像学真正反应者方面的敏感性为62%。CEA水平升高在预测病情进展方面的敏感性为70%。关于诊断准确性，CEA水平变化在预测影像学真正反应者和病情进展方面分别为65%和85%。在24个月的随访中，CEA水平显著下降的患者生存时间明显长于无反应者（P = 0.0184，对数秩检验）。
CEA水平测量可能有助于监测转移性结直肠癌患者的化疗反应及预测预后。当影像学检查在临床实践中不适于评估反应时，血清CEA水平可作为监测化疗反应的一种手段。
