PB0916 - The role of anticoagulation in the management of tumour thrombosis: A single centre retrospective study

Background: There are numerous guidelines addressing anticoagulation in cancer associated thrombosis and the role of direct oral anticoagulants (DOAC), yet there is no consensus regarding the role of anticoagulation in tumour thrombosis and whether or not it has any impact on survival.

Aims: We conducted a single centre retrospective observational study reviewing the diagnosis, management and outcomes of tumour thrombus and the role of anticoagulation.

Methods: CT reports with the term “tumour thrombus” between 2019 and 2021 were identified. Electronic patient records were reviewed to identify patient demographics, site of tumour thrombus, management and outcome.

Results: 68 patients were identified. The baseline characteristics are documented in (table 1).
The most common malignancy was renal (32% of patients), correlating with the most common thrombus sites identified as the inferior vena cava and renal vein (table 2).
46/68 (68%) received anticoagulation and 22/68 (32%) were never anticoagulated. Resolution of tumour thrombus occurred in 14% of those therapeutically anticoagulated, 10% prophylactically anticoagulated and 9% not anticoagulated.
2/36 therapeutically anticoagulated patients and 2/22 of those patients not anticoagulated developed progressive tumour thrombus in association with disease progression.
There were 5 major bleeding events as defined by ISTH criteria requiring intervention or admission. Four of these occurred on therapeutic anticoagulation and one on prophylaxis.
39% of those therapeutically anticoagulated and 41% of patients not anticoagulated died by 6 months.

Conclusion(s): This small observational cohort did not demonstrate a positive impact of anticoagulation on six month survival. Treatment of the underlying malignancy is likely the main predictor of resolution or progression of tumour thrombus. The distinction between tumour thrombus and bland thrombus radiologically is critical and can be challenging but important and would guide management with regard to the need for anticoagulation. Further larger studies are required to corroborate our findings and potentially identify those patients who might benefit from anticoagulation.