Catheter-Related Thrombosis in Recipients of Autologous Hematopoietic Cell Transplantation (AHCT) with Myeloma and Lymphoma: Risk Factors and Management

Background: There is limited data regarding the incidence, risk factors, management and outcomes of catheter-related thrombosis (CRT) in patients with lymphoma or myeloma undergoing AHCT. Methods: In a retrospective study with nested case-control risk factor analysis, we examined 789 AHCT recipients with lymphoma and myeloma transplanted between 2006-2016. All patients had tunneled 14.5fr double lumen large bore central venous catheter inserted for peripheral blood hematopoietic cell apheresis and infusion. We identified 50 CRT episodes. Case-control analysis included 50 CRT cases and controls (no CRT) matched 1:2 by age and disease. The primary objective was to characterize CRT incidence and management. Secondary objective was to identify CRT risk factors. Results: The incidence of CRT in patients with lymphoma and myeloma undergoing AHCT was 6.3% (n = 50); with 32% symptomatic. Incidence was higher is NHL (10%) and HL (11%) compared to myeloma (2.1%). At the time of CRT, all patients had platelet recovery with median platelet count was 133 (range 31-426 × 109/L). Almost all CRT cases (90%) had internal jugular insertion. The time from line placement to CRT varied from 11 to 89 days. Five patients had pulmonary embolism detected incidentally by routine CT imaging; all were asymptomatic. The median age was 56.6 years. Prior radiation to chest/neck (18%), bulky mediastinal mass (12%), splenectomy (6%), peri-transplant line infection (18%), hormonal therapy (8%), and prior VTE (16%) were common amongst CRT cases. Concomitant port-a-cath (50%) and more than one CVC inserted peritransplant (46%) were also common. Most (86%) CRTs were treated with low molecular weight heparin (LMWH) and 56% received subsequent warfarin. Only 2% had unfractionated heparin. LMWH at dose 1 mg/kg twice daily was administered if platelet count could be maintained above 50 × 109/L. Patients were anticoagulated for <3 months (38%), 3-6 months (24%), and >6 months (22%). One patient required lytic therapy for CRT. Only two patients (4%) received secondary prophylactic anticoagulation after AHCT. This management was safe and grade 1-2 bleeding events occurred in only two patients (4%) during anticoagulation. 12% had subsequent VTE after CRT. No deaths occurred due to CRT or its treatment. Risk factors for CRT included prior VTE event (21% vs 7%, P = .02); high peak WBC at mobilization (43 vs 40 × 109/L) and after engraftment (15.2 vs 11.9 × 109/L) tended to increase CRT risk. Two-year progression-free survival of entire group was 54% (95% CI 50-57%) and was not affected by CRT (P = .42). Conclusions: The diagnosis of CRT often complicates AHCT and appears to be more common in lymphoma than myeloma patients. Anticoagulation with LMWH or warfarin appeared safe, however many patients had recurrent VTE events. Further study to define additional risk factors and examine the management strategies is warranted.