Significance of cancer detection in the anterior lateral horn on systematic prostate biopsy: the effect on pathological findings of radical prostatectomy specimens

OBJECTIVE: To clarify the significance of cancer detection in the anterior lateral horn (ALH) on systematic prostate biopsy in relation to its effect on the pathological findings from retropubic radical prostatectomy (RRP) specimens. PATIENTS AND METHODS: The study included 84 consecutive patients who underwent RRP at our institution between January 1999 and December 2002, after being diagnosed as having prostate cancer, based on systematic prostate biopsies that included the areas taken by standard sextant biopsies and the bilateral ALHs. Several clinicopathological factors of these patients were analysed in relation to the presence or absence of cancer in the ALH on systematic biopsy. RESULTS: Of the 84 patients, cancer was detected in the ALH in 44 (group A), but not in the remaining 40 (group B). There were no significant differences in age, preoperative serum prostate-specific antigen level, or prostate volume between the groups. However, the incidence of bilateral positive cores and the percentage of positive biopsy cores in group A were significantly higher than those in group B. Pathological examinations of RRP specimens showed no significant differences in the incidence of lymphatic invasion, vascular invasion and perineural invasion, or Gleason score between the groups, but group A had a significantly larger tumour volume and higher incidence of extraprostatic disease than group B. CONCLUSIONS: Despite similar biological tumour characteristics and irrespective of the cancer location in the ALH, advanced and extensive disease frequently involves the ALH. Therefore, more aggressive treatment should be considered if cancer is detected in the ALH by systematic prostate biopsy.