Metastatic Involvement of the Prostatic Anterior Fat Pad: Implications for the Pathologist.

Objectives: There is little information regarding the utility of pathologic evaluation of the prostatic anterior fat pad (PAFP) in patients with a low preoperative probability of recurrence. Our study aimed to determine the utility of PAFP pathologic examination, especially for this group of patients.
Methods: We analyzed a tertiary care academic center's radical prostatectomy (RP) specimens from 2009 to 2017.
Results: Of 602 RP specimens, 420(70%) included the PAFP; four of 420 (1%) had lymph node involvement (LNI) in the PAFP. In two of four cases with LNI in the PAFP, this was the only site of LNI. Of these two cases, one occurred in a patient with low probability of recurrence and involved a nonpalpable PAFP lymph node.
Conclusions: Pathologic evaluation of the PAFP may be useful even in patients with low probability of recurrence because it may change staging by detecting metastatic involvement of small PAFP lymph nodes.