Figure 5.

Principles behind prostate biopsy. (a) The various biopsy schemes used, in the coronal plane. The first is the classic sextant pattern, which misses about 25% of cancers. The next three schemes illustrate the octant, 10-core and 12-core regimes, respectively. In current practice the 10- or 12-core regime is favoured. (b) Prostate biopsy is a systematic sampling technique and the diagram shows that the cores are preferentially targeted onto the peripheral zone as most cancers occur here. Note how the trajectories are aimed anterolaterally to maximise peripheral zone sampling. Reproduced with permission from [14].