Treatment of catheter-related thrombosis in patients with hematologic malignancies: A Venous thromboEmbolism Network U.S. retrospective cohort study.

INTRODUCTION: Optimal treatment of catheter-related thrombosis (CRT) is uncertain in patients with hematologic malignancy. We aimed to evaluate the treatment strategies, outcomes, and predictors of recurrent venous thromboembolism (VTE) associated with catheter-related thrombosis (CRT) in patients with hematologic malignancy. METHODS: We performed a multicenter retrospective cohort study of eight institutions through the Venous thromboEmbolism Network US. Patients with hematologic malignancies with documented CRT were identified using ICD-9 and ICD-10 diagnostic codes. Semi-competing risks proportional hazard regression models were created. RESULTS AND CONCLUSIONS: Of the 663 patients in the cohort, 124 (19%) were treated with anticoagulation alone, 388 (58%) were treated with anticoagulation and catheter removal, 119 (18%) treated with catheter removal only, and 32 (5%) had neither catheter removal nor anticoagulation. 100 (15%) patients experienced a recurrent VTE event. In the 579 patients who had catheter removal, the most common reason for catheter removal was the CRT [392 (68%)]. For subjects who received any anticoagulation (n = 512), total anticoagulation duration was not associated with VTE recurrence [1.000 (0.999-1.002)]. After adjustment patients treated with catheter removal only had an increased risk of VTE recurrence [2.50 (1.24-5.07)] and death [4.96 (2.47-9.97)]. Patients with no treatment had increased risk of death [16.81 (6.22-45.38)] and death after VTE recurrence [27.29 (3.13-238.13)]. In this large, multicenter retrospective cohort, we found significant variability in the treatment of CRT in patients with hematologic malignancy. Treatment without anticoagulation was associated with recurrent VTE.

Risk of pulmonary emboli after removal of an upper extremity central catheter associated with a deep vein thrombosis.

Standard treatment of catheter-associated upper extremity deep vein thrombosis (UE-DVT) is anticoagulation, although catheters are often removed for this indication. The optimal time for catheter removal and whether the act and/or timing of catheter removal is associated with pulmonary embolism (PE) remain unknown. A retrospective cohort study was performed at 8 participating institutions through the Venous thromboEmbolism Network US. Patients with hematologic malignancies and central venous catheter (CVC)-associated UE-DVT were included from 1 January 2010 through 31 December 2016. The primary outcome was objectively confirmed PE within 7 days of UE-DVT diagnosis in anticoagulated patients comparing early (≤48 hours) vs delayed (>48 hours) catheter removal. A total of 626 patients were included, among whom 480 were treated with anticoagulation. Among anticoagulated patients, 255 underwent early CVC removal, while 225 had delayed or no CVC removal; 146 patients received no anticoagulation, among whom 116 underwent CVC removal alone. PE within 7 days occurred in 2 patients (0.78%) with early removal compared with 1 patient (0.44%) with delayed or no CVC removal (P > .9). PE or any cause of death within 7 days occurred in 3 patients in both the early removal (1.18%) and delayed/no removal (1.33%) groups (P > .9). In patients treated with CVC removal only (no anticoagulation), there were no PEs but 3 deaths within 7 days. In patients with hematological malignancy and CVC-associated UE-DVT, early removal of CVCs was not associated with an increased risk of PE compared with delayed or no removal.

Seroconversion rates following COVID-19 vaccination among patients with cancer.

As COVID-19 adversely affects patients with cancer, prophylactic strategies are critically needed. Using a validated antibody assay against SARS-CoV-2 spike protein, we determined a high seroconversion rate (94%) in 200 patients with cancer in New York City that had received full dosing with one of the FDA-approved COVID-19 vaccines. On comparison with solid tumors (98%), a significantly lower rate of seroconversion was observed in patients with hematologic malignancies (85%), particularly recipients following highly immunosuppressive therapies such as anti-CD20 therapies (70%) and stem cell transplantation (73%). Patients receiving immune checkpoint inhibitor therapy (97%) or hormonal therapies (100%) demonstrated high seroconversion post vaccination. Patients with prior COVID-19 infection demonstrated higher anti-spike IgG titers post vaccination. Relatively lower IgG titers were observed following vaccination with the adenoviral than with mRNA-based vaccines. These data demonstrate generally high immunogenicity of COVID-19 vaccination in oncology patients and identify immunosuppressed cohorts that need novel vaccination or passive immunization strategies.