2013 年 39 巻 9 号 p. 552-557
We report the case of a patient with non-small cell lung cancer in whom periodic testing for D-dimer led to early detection of pulmonary embolus caused by bevacizumab. The patient was a man in his 60 s, diagnosed as having non-small cell lung cancer. He had been treated with 4 courses of bevacizumab/carboplatin/paclitaxel combination therapy as first-line therapy, followed by maintenance therapy with bevacizumab only. After 4 courses of maintenance therapy, progression of the primary tumor was confirmed. Combination therapy with bevacizumab/cisplatin/pemetrexed was initiated as second-line therapy. Compared to baseline, the D-dimer level was markedly elevated at 13.0 μg/mL on day 14 of the first course. Therefore, computed tomography (CT) was performed. This confirmed the presence of a thrombus in the right pulmonary artery. Anticoagulation therapy using warfarin, 2 mg/day, was initiated. The international normalized ratio of prothrombin time was well controlled at 1.45 with the administration of warfarin, 3 mg/day. CT performed again on day 29 of starting warfarin administration showed that the thrombus had disappeared. Therefore, warfarin administration was discontinued after 31 days.
In the case of our patient, we noted markedly elevated levels of D-dimer by testing for D-dimer once a month, and thus, we could initiate anticoagulation therapy before the patient suffered from symptoms of pulmonary embolus. As a result, the thrombus could be dissolved rapidly. Therefore, we suggest that testing for D-dimer before initiating chemotherapy and periodic testing facilitates the early detection of pulmonary embolus and thus early initiation of anticoagulation therapy.