Incidence, Risk, and Markers of Thrombosis in AML Patients - Single Institution Experience

INTRODUCTION

Thrombotic episodes represent significant morbidity and mortality in patients with hematologic malignancies and may be influenced by several risk factors. Current predictive and prognostic models do not take into account several risk factors. Furthermore, prophylactic and therapeutic management of thrombosis remains to be standardized for patients with AML. Few studies report the impact of catheters to the likelihood of thrombosis. We comprehensively report our institution's experience with thrombosis in AML patients.

METHODS

The Total Cancer Care (TCC) database was used to retrospectively chart review patients with histologically confirmed AML from 2000 to 2018. Several parameters were extracted including but not limited to history of thrombosis and recurrences, chemotherapy regimens, and laboratory values for significant events. All statistical analyses were performed using SPSS v24.0 and GraphPad Prism 7.

RESULTS: A total of 1101 patients were diagnosed with either de novo (516, 46.87%) or secondary (584, 53.04%) AML. The median age of diagnosis was 75 years (52, 95) and men were the majority, 726 (65.94%). In terms of cytogenetics, 25 (2.27%) had good/favorable, 616 (55.95%) had intermediate, and 334 (41.75%) had poor cytogenetics. At the time of diagnosis, CBC revealed median WBC of 3 (0, 420), ANC 1 (0, 132), Plt 52 (1, 996), and hgb 9 (1, 15). Median ECOG score was 1.

159, 14.4% patients had a history of thrombosis prior to AML diagnosis; with a median of 1 episode of thrombosis (1, 4). After AML diagnosis 70 patients had one episode of thrombosis, 9 had two episodes, and 2 patients had three recurrent episodes.

As far as the first-line induction therapy, 247 (22.43%) patients received 7+3, 12 (1.08%) received CLAG, 36 (3.27%) received hypomethylating agents, and the remaining 227 (2.06%) received other therapies such as clinical trials or off-label drugs. Repeat cycles of therapies were also recorded.

In terms of growth factor use after AML diagnosis, 132 (11.99%) used EPO, 209 (18.98%) G-CSF, 32 (2.90%) GM-CSF, and 778 (70.66%) used any other growth factor not mentioned.

Out of the 139 episodes of thrombosis, 81 (58.3%) were venous, and 58 (41.7%) were arterial. Among the venous, 45 (55.6%) were lower extremities, 21 (25.9%) were upper extremities, and 10 (12.3%) were pulmonary embolus. Among the arterial thrombosis, 27 (46.6) were coronary events, 23 (39.7%) were cerebral events.

Only 15 patients had catheter-associated thrombosis events, 11 (73.3%) were PICC, and 2 (13.3%) were Port lines or central lines.

In terms of management, 39 patients were on temporary anticoagulation, 60 patients were on indefinite anticoagulation, and 522 were not on any anticoagulation.

In terms of complications, 3 patients had minor bleeding, 1 had major bleeding, 2 had HIT and the large majority of 419 had no complications of anticoagulation.

CONCLUSIONS:

Thrombosis both venous and arterial events manifest during treatment for leukemias. PICCs lines are associated with more catheter associated thrombosis events than ports. Further prospective studies are needed to evaluate the risk of both arterial and venous thrombosis in patients with acute leukemia. Further risk mitigation strategies are needed.