Efficacy and safety of anticoagulant treatment for venous thromboembolism (VTE) may vary in patients with different cancer sites. We evaluated the rates of VTE recurrence and major bleeding and the relative efficacy and safety of 6-month treatment with oral apixaban or subcutaneous dalteparin in patients with different cancer sites randomized in the Caravaggio study. Primary cancer was located at gastrointestinal sites in 375 patients (32.5%), lung in 200 (17.3%), breast in 155 (13.4%), genitourinary sites in 139 (12%), gynecological sites in 119 (10.3%), and was hematological in 85 patients (7.4%). Rates of VTE recurrence were 10.9% in patients with gynecological, 8.8% with gastrointestinal, 6.5% with genitourinary, and 5.5% with lung cancer with lower rates in the other sites of cancer. Rates of major bleeding were 7.2% in patients with genitourinary and 4.8% with gastrointestinal cancer, with lower rates in patients with other sites of cancer. The observed absolute risk difference in VTE recurrence in favor of apixaban was 11.9% in patients with gynecological, 5.5% with lung, 3.7% with genitourinary cancer, and 0.6% with gastrointestinal cancer. None of the risk differences was statistically significant. The rates of major bleeding in patients treated with apixaban or dalteparin was similar across patients with different cancer sites. In conclusion, recurrences appear to be more common in patients with gastrointestinal and gynecological cancer and major bleedings in patients with genitourinary and gastrointestinal cancer. Oral apixaban is a valid oral alternative to subcutaneous dalteparin for the treatment of a large spectrum of patients with cancer-associated VTE.

静脉血栓栓塞 (VTE) 的抗凝治疗的疗效和安全性可能因癌症部位不同的患者而异。我们评估了在 Caravaggio 研究中随机分配的不同癌症部位患者的 VTE 复发率和大出血率，以及口服阿哌沙班或皮下达肝素 6 个月治疗的相对疗效和安全性。原发性癌症位于 375 名患者 (32.5%) 的胃肠道部位，200 名患者 (17.3%) 的肺癌部位，155 名 (13.4%) 的乳腺癌患者，139 名 (12%) 的泌尿生殖部位，119 名 (10.3%) 的妇科部位，以及85 名患者 (7.4%) 是血液学检查。妇科患者的 VTE 复发率为 10.9%，胃肠道患者为 8.8%，泌尿生殖系统患者为 6.5%，肺癌患者为 5.5%，其他部位癌症的复发率较低。大出血发生率为 7。泌尿生殖系统癌症患者为 2%，胃肠道癌症患者为 4.8%，其他部位癌症患者的发病率较低。在妇科患者中观察到的 VTE 复发有利于阿哌沙班的绝对风险差异为 11.9%，肺癌患者为 5.5%，泌尿生殖系统癌患者为 3.7%，胃肠道癌患者为 0.6%。风险差异均无统计学意义。在不同癌症部位的患者中，接受阿哌沙班或达肝素治疗的患者的大出血率相似。总之，胃肠道和妇科癌症患者的复发似乎更常见，泌尿生殖系统和胃肠道癌症患者的大出血似乎更常见。