Cluster 234: biopsy bronchoscopic accessed percutaneous thoracoscopic safely perspective undergo willingness waived 
Cluster 516: biopsy tumor accessible undergo patients amenable core biopsies treatment tissue 
Cluster 538: needle biopsy core fine aspiration fna breast diagnosis tumor invasive 
Cluster 1108: tumor primary brain patients biopsies positive biopsy metastatic diagnosis resection 
Cluster 2430: undergo willing biopsy biopsies tumor willingness treatment able pre research