|Recurrent Venous Thromboembolism|
International Registry on recurrent venous thromboembolism in anticoagulated patients with cancer
In a population of patients with newly diagnosed VTE 20-40% (depending on selection) have concomitant cancer disease. There is a high risk of both recurrent VTE (6.8-27% per year in 3 studies) and of major bleeding complications (5.4-13.3% per year) on anticoagulant treatment with vitamin K antagonists (VKA) in patients with cancer compared to those without (Hutten BA 2000; Palareti G 2000; Prandoni P 2002). Two trials have demonstrated that the composite end point of recurrent VTE and major bleeding is lower during secondary prophylaxis with low-molecular-weight heparin (LMWH) than with VKA (Meyer G 2002, Lee AY 2003). The 7 th edition of the ACCP guidelines therefore recommends LMWH for the secondary prophylaxis for 3 to 6 months after VTE in patients with cancer (Büller H 2004). For patients with recurrent VTE during anticoagulant therapy there is a paucity of data and no guidelines.
Description of Registry:
This registry will collect data on some baseline characteristics, treatment used, effect and safety in patients with cancer and recurrence of VTE on anticoagulant therapy. The registry will be under the auspices of International Society on Thrombosis and Haemostasis (ISTH) and its Standardization and Scientific Committees (SSC), subcommittee of Control of AnticoagulationandSubcommittee of Hemostasis and Malignancy. The registration form will be downloaded from the web-site of the ISTH. Participation will be encouraged by e-mails and presentations at SSC meetings and appropriate congresses and by a small financial remuneration.
The first time a representative of a clinic registers a case, some basic data on the clinic will also be requested (type of hospital, average # of patients with VTE treated per year, vicinity to oncology clinic, treatments used in patients with VTE but without cancer).
On each case the following data will be requested: year of birth, sex, type and stage of cancer, concomitant chemotherapy, # of VTE events including the present one, date and anticoagulant treatment (generic name and dose/24 h of VKA, LMWH, heparin) when the present event was diagnosed, diagnostic method, INR and APTT/anti-Xa (if applicable) closest to that date, anticoagulant treatment given initially and as secondary prophylaxis after this event, levels of anti-Xa, APTT and INR during the following 3 months. At 3 months information on additional recurrence of VTE, major bleeding and survival is collected.
The data can be submitted collectively at 3 months or in 2 stages. For cases with initial data submitted but the 3-month data missing at 4 months, a research nurse will use fax and e-mail reminders to request follow-up data. All submissions of data are done by fax. An identification number is generated, composed of center number (3 digits starting from 001 in consecutive order) + year of birth (last 2 digits) + date of diagnosis of the present event (YYMMMDD), S 12 digits, and e-mailed back to the investigator as confirmation of receipt of partial or complete data.
The purpose of this registry is to acquire information on current practices for management of recurrent VTE in patients with cancer. It will also provide a basis future research on optimal treatment of these events. The database will be housed at Thrombosis Service, Hamilton Health Sciences/Department of Medicine, McMaster University.
Separate IRB approval will be requested for each specific research study that uses data from the repository.
Data to be included in the registry:
Data that will be included will be de-identified. Data will include basic information on the malignancy and on the present and previous venous thromboembolic episodes, the treatment provided and outcome data on recurrence, bleeding and death. The data collection form is attached. The database will be publicized, not only on the website, but through annual meetings. Data collectors will complete the case record form and fax it together with de-identified reports from objective diagnostic investigations of the thromboembolic event to the principal investigator. The project coordinator will assign a center number to each center and report this number to the data collector. The number of subjects will be 200, but may be extended.
Security and confidentiality:
De-identified data will be faxed to the principal investigator at Hamilton General Hospital, Thrombosis Service. The project coordinator will enter the data into the database. This electronic database will be housed on a secure server that Hamilton Health Sciences Technical Services supports. The only personal data that will be recorded on the case record forms and entered into the database are year of birth and sex. All data collection forms will be stored in a locked file in the project coordinator’s office. Any studies using data from the database will not contain any identifying information.
Access to the data:
Only the principal investigators, Dr. Schulman, Dr Falanga, and the project coordinator will have direct access to the data. Requests for research studies may be directed to Dr. Schulman and a separate IRB protocol will be submitted.
Consent and authorization:
Consent will be obtained from subjects at their individual sites according to the national or regional regulations. A template consent form is offered on the ISTH website as an example that can be modified and submitted to local IRBs. The form clearly states that subjects are giving permission for their data to be stored in the database.
Risks and benefits of participation:
The subject’s involvement is limited to the information that is collected. There are potential risks of loss of privacy. There is no compensation to the patients for their participation. Information acquired from the registry may benefit patients with cancer and recurrent thrombosis in the future. Subjects may withdraw their consent at any time during the pregnancy. The data entered into the registry up to that time-point will remain in the registry but no further collection will occur.
Sam Schulman, MD
Anna Falanga, MD