Hematology Service, Clínica Universidad de Navarra, Pamplona, Spain.
Int J Cancer. 2013 Nov;133(9):2157-64. doi: 10.1002/ijc.28229. Epub 2013 May 29.
Extensive screening strategies to detect occult cancer in patients with unprovoked venous thromboembolism (VTE) are complex and no benefit in terms of survival has been reported. FDG-PET/CT (2-[F-18] fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography), a noninvasive technique for the diagnosis and staging of malignancies, could be useful in this setting. Consecutive patients ≥ 50 years with a first unprovoked VTE episode were prospectively included. Screening with FDG-PET/CT was performed 3-4 weeks after the index event. If positive, appropriate diagnostic work-up was programmed. Clinical follow-up continued for 2 years. Blood samples were collected to assess coagulation biomarkers. FDG-PET/CT was negative in 68/99 patients (68.7%), while suspicious FDG uptake was detected in 31/99 patients (31.3%). Additional diagnostic work-up confirmed a malignancy in 7/31 patients (22.6%), with six of them at early stage. During follow-up, two patients with negative FDG-PET/CT were diagnosed with cancer. Sensitivity (S), positive (PPV) and negative predictive values (NPV) of FDG-PET/CT as single tool for the detection of occult malignancy were 77.8% (95% CI: 0.51-1), 22.6% (95% CI: 0.08-0.37) and 97.1% (95% CI: 0.93-1), respectively. Median tissue factor (TF) activity in patients with occult cancer was 5.38 pM vs. 2.40 pM in those without cancer (p = 0.03). Limitation of FDG-PET/CT screening to patients with TF activity > 2.8 pM would improve the PPV to 37.5% and reduce the costs of a single cancer diagnosis from 20,711€ to 11,670€. FDG-PET/CT is feasible for the screening of occult cancer in patients with unprovoked VTE, showing high S and NPV. The addition of TF activity determination may be useful for patient selection.
广泛的筛查策略旨在检测无诱因静脉血栓栓塞症（VTE）患者的隐匿性癌症，但目前尚无生存获益的报道。18F-氟代脱氧葡萄糖正电子发射断层扫描/计算机断层扫描（FDG-PET/CT）是一种用于恶性肿瘤诊断和分期的非侵入性技术，可能对此类患者有用。本前瞻性研究连续纳入了 99 例首次无诱因 VTE 发作且年龄≥50 岁的患者。在指数事件后 3-4 周进行 FDG-PET/CT 筛查。如果结果阳性，则进行适当的诊断性检查。临床随访持续 2 年。采集血样以评估凝血生物标志物。99 例患者中，68 例（68.7%）FDG-PET/CT 结果为阴性，31 例（31.3%）可疑 FDG 摄取。进一步的诊断性检查在 31 例中确诊了 7 例（22.6%）恶性肿瘤，其中 6 例为早期。在随访期间，2 例 FDG-PET/CT 阴性的患者被诊断为癌症。FDG-PET/CT 作为隐匿性恶性肿瘤检测的单一工具，其敏感性（S）、阳性预测值（PPV）和阴性预测值（NPV）分别为 77.8%（95%CI：0.51-1）、22.6%（95%CI：0.08-0.37）和 97.1%（95%CI：0.93-1）。隐匿性癌症患者的组织因子（TF）活性中位数为 5.38 pM，而无癌症患者的 TF 活性中位数为 2.40 pM（p=0.03）。将 FDG-PET/CT 筛查仅限于 TF 活性>2.8 pM 的患者，可将 PPV 提高至 37.5%，并将单个癌症诊断的成本从 20711 欧元降低至 11670 欧元。FDG-PET/CT 可用于检测无诱因 VTE 患者的隐匿性癌症，具有较高的 S 和 NPV。TF 活性测定的添加可能有助于患者选择。
