Manifestations of the Antiphospholipid Syndrome in Patients with Malignancies.

The presence of antiphospholipid antibodies has been reported in a large variety of malignancies. It is not clear, however, if the antiphospholipid antibodies are related to thrombotic associations of the antiphospholipid syndrome (APS) in these patients. We investigated the frequency of thrombotic manifestations in 58 patients with the presence of antiphospholipid antibodies and a history of neoplasia, including haematologic and lymphoproliferative malignancies.

Methods Antiphospholipid antibodies were detected by clotting assay (lupus anticoagulant, LA) or by enzyme-linked immunosorbent assay (anticardiolipin antibodies). LA were tested by more than 2 different methods according to the proposed criteria of the SSC of the ISTH.

Results 39/58 patients suffered from solid tumours mostly from carcinoma of the breast, prostate, and colon and 19/58 patients from malignant haematologic or lymphoproliferative diseases mostly from Non-Hodgkin lymphoma. One patient was suffering simultaneously from two carcinomas of the prostate and the testicle and a Non-Hodgkin’s lymphoma.

Among the patients with solid tumours 18/39 (46 %) patients had thromboembolic complications of the antiphospholipid syndrome. Among the patients with haematologic and lymphoproliferative malignancies only 6/19 (32 %) suffered from thromboembolic complications. Thrombotic manifestations were more common on the arterial than the venous site. There was no relation between the titres of aCL antibodies and the rate of clinical manifestations. In two patients aPL disappeared after the effective treatment of the tumor. Especially patients with very high titres did not present any thromboembolic manifestation.

Conclusion The presence of antiphospholipid antibodies may identify a subset of cancer patients with high risk of developing thrombotic complications but the frequency of thrombosis is lower in aPL positive patients with lymphoproliferative and haematological malignancies. Especially in these patients very high titres of aCL antibodies do not seem to be associated with clinical manifestations of the APS.