6. Treatment with anticoagulants other than 4-hydroxycoumarin derivatives or antiplatelet drugs. Patients in treatment with heparin can interrupt treatment 24h prior to biopsies and resume treatment 12h after biopsy has been performed. In case of patients treated with clopidogrel or salicylates, they should be able to interrupt treatment 5-7 days before biopsy and resume 24h after.