PO31 | MIGRATORY SUPERFICIAL THROMBOPHLEBITIS REFRACTORY TO APIXABAN IN A PATIENT WITH LUNG ADENOCARCINOMA

I. Goldberg^1|2, P. Raanani^1|2|3, G. Spectre^1|2 | ¹Institute of Hematology, Beilinson Hospital, Rabin Medical Center, Petah Tikva, Israel; ²Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv, Israel; ³Felsenstein Medical Research Center, Rabin Medical Center, Petah Tikva, Israel

Introduction. Migratory superficial thrombophlebitis, classically described as part of Trousseau syndrome, is a rare paraneoplastic manifestation. It is most commonly associated with pancreatic and gastric adenocarcinoma but has also been reported in lung, ovarian, and brain malignancies. Its pathogenesis is multifactorial and involves tumor-derived procoagulants, inflammatory cytokines, and endothelial and platelet activation. In recent years, management of cancer-associated thrombosis has shifted from low molecular weight heparin (LMWH) to direct oral anticoagulants (DOACs). However, data regarding the efficacy of DOACs in migratory superficial thrombophlebitis are lacking. We report a case of migratory superficial thrombophlebitis progressing despite full-dose apixaban therapy.

Case presentation. A 55-year-old woman presented to a different hospital with concurrent superficial vein thromboses in the right upper limb (basilic vein) and in the right lower limb (great saphenous vein). Evaluation excluded infectious, autoimmune, and inherited thrombophilia and antiphospholipid antibodies. Given the atypical clinical presentation, CT imaging of the chest, abdomen, and pelvis was performed and revealed stage III lung adenocarcinoma, consistent with Trousseau syndrome. Molecular profiling demonstrated KRAS Q61H and TP53 mutations with HER2 protein overexpression. She was initially treated with full-dose LMWH and, after four weeks, was switched to apixaban 5 mg twice daily. She was referred to our Oncology Institute and systemic induction chemotherapy with cisplatin and etoposide was initiated. Despite reported good adherence to apixaban, she developed a new superficial thrombosis in the great saphenous vein in the left lower limb three months after the first thrombotic event. Anticoagulation was changed back to therapeutic-dose LMWH, after which no further thrombotic events occurred despite progression of the malignant disease.

Conclusions. We report a case of lung adenocarcinoma associated with migratory superficial thrombophlebitis, which progressed despite treatment with full-dose apixaban. Given the complex pathogenesis of cancer-associated migratory superficial thrombophlebitis, including tumor-derived procoagulants and inflammatory mediators, the efficacy of DOACs in this setting is uncertain. Further studies are needed to define the optimal anticoagulant strategy in this population.