Very distal apical prostate tumours: identification on multiparametric MRI at 3 Tesla

OBJECTIVE To describe an undescribed 'very distal' apical prostate cancer on multiparametric MRI (mpMRI) since apical prostate cancer can be difficult to detect in transrectal ultrasound guided biopsy and might therefore be missed in treatment decisions such as high intensity focused ultrasound or surgical therapy. PATIENTS AND METHODS From January 2011 to December 2012 a total of 210 consecutive patients underwent 3 T mpMRI with endorectal coil followed by our previously described MRI/ultrasound image fused and directed TRUS biopsies. Patients also underwent 12-core TRUS sextant biopsies. The inclusion criteria required at least one distal apical prostate lesion visualized on mpMRI and targeted for biopsy. RESULTS A total of 38 men (median age 62 years, median PSA 7.68 ng/dL) were identified as having distal apical prostate cancer on mpMRI. Thirteen patients (34%) had a prior diagnosis of cancer and were on active surveillance protocols while 25 (66%) did not. Of those patients, 21 (55%) had undergone a median of two prior negative biopsies. Twenty-two patients (58%) were positive on biopsy for prostate cancer. On breakdown of patients who were positive, 17 (77%) were positive on TRUS random biopsies and 21 (95%) were positive on MRI targeted biopsies with the majority of patients having multifocal disease. At the distal apical lesions of interest, 80% were positive on MRI targeted biopsy. In addition 33% of these patients were upgraded based on MRI targeted biopsy at the distal lesion. CONCLUSIONS Very distal apical prostate cancer can be accurately detected and sampled with mpMRI and subsequent MRI/ultrasound fusion biopsy. This may aid clinicians and patients in decision making for therapeutic modalities.