Deep Vein Thrombosis Risk - First External Physical Marker - Multiple Lipomas Associated with Thrombophilia

Purpose and Background: Thrombophilia is the increased tendency to form thrombi, often silent, usually due to innate usually familial mutations. Venous thrombosis has an incidence of approximately 0.1% in the general adult population ^1,2,3. Deep vein thrombosis (DVT) with pulmonary emboli (PE) can be fatal in up to 25% of patients with PEs. A family with both familial multiple lipomas ^4,5 and familial thrombophilia with DVTs and PEs led to the question of whether multiple lipomas and thrombophilia are associated. Thrombophilia is unsuspected unless abnormal clotting occurs. Multiple lipomas if correlated would be the first finding, other than venous stasis pathology, of external marker for thrombophilia.

Methods: For the period 1999-2014, we retrospectively reviewed one surgeon’s consecutive adult patients with removed lipomas.  We recorded available chart history of personal and familial lipomas, personal and familial venous thrombotic events, and thrombophilia testing.    Screening of lipoma patients for personal and/or familial history of thrombophilia, and clinical testing for thrombophilia abnormalities (Factor V Leiden deficiency, and Proteins S and C deficiencies) were begun at the time that multiple lipomas and thrombophilia were suspected to be correlated, and thus full history and blood testing of early lipoma patients had not been done.

Results: 176 adults had removed lipomas, of whom 49 had multiple lipomas by history and/or physical examination. Of these 49 patients, 7 (14.3%) had had a personal thrombotic event and 7 (14.3%) had familial history of thrombotic event (95% confidence interval 4.5%-24.1%, p<0.001 compared to incidence in the general population).  9 multiple lipoma patients had laboratory testing for thrombophilia, with 5 positive for thrombophilic abnormalities and 4 negative. Both personal and familial multiple lipomas were found in 13 patients, and in this group, 3 (23.1%) had had a personal thrombotic event and 4 (30.8%) had a familial thrombotic event.

Conclusions: This retrospective study suggests that comparing to the incidence of venous thrombosis in the general adult population, patients with visible multiple lipomas have a previously unknown significantly higher risk (28.6% combined) of personal and/or familial venous thrombosis.  To our knowledge, this is the first identification of an external physical marker for silent and potentially deadly thrombophilia and DVT/PE risk.