Focal therapy for prostate cancer: pathologic basis

To summarize pathologic features of low-volume, low-risk prostate cancer relevant to the development of patient selection criteria and treatment strategies for focal therapy of prostate cancer, as an alternative to whole-gland radical treatments.

Prostate cancer characteristically presents as a multifocal lesion within the prostate gland. Diagnosis of prostate cancer at an early stage has led to a recognition of subsets of patients whose disease may be either unifocal or multifocal, yet is unilateral or of small aggregate volume. Parenchyma-preserving partial-gland ablation may become a potentially feasible option in future treatment of early-stage, localized prostate cancer.

Even for moderately selective protocols such as hemiablation, however, appropriate patient selection will be challenging because of the imperfect correlation among unifocality, unilaterality, low volume and low grade. Extended multicore biopsy protocols under imaging guidance may be required to map the tumor process with sufficient accuracy for treatment planning. Further research in molecular determinants and more precise imaging techniques should be pursued to optimize selection and treatment.