Pathologic implications of prostatic anterior fat pad

doi:10.1016/j.urolonc.2010.09.003

Urologic Oncology: Seminars and Original Investigations

Volume 31, Issue 1, January 2013, Pages 63-67

https://doi.org/10.1016/j.urolonc.2010.09.003 Get rights and content

Abstract

Objective

Lymph node status has significant pathologic implications in patients with prostate cancer. In this study, we have performed pathologic analysis of prostatic anterior fat pad (PAFP) excised during robot-assisted radical prostatectomy (RARP) to investigate the potential role of AFP on pathologic staging of prostate cancer.

Methods

A total of 258 consecutive patients underwent PAFP excision during RARP between July 2007 and June 2009. PAFP was removed and submitted en bloc to the pathology department and evaluated for the presence of lymphoid tissue and metastatic prostate cancer. Retrospective chart review was performed for all patients.

Results

Of the 258 patients, 30 (11.6%) had 1 or 2 PAFP lymph nodes and 228 (88.4%) men showed no lymphoid tissue in their PAFPs. Preoperatively, mean PSA level was higher in the former group. There were no significant pathologic differences between the 2 groups. Among the 30 patients with PAFP lymph nodes, 3 were positive for metastatic prostate cancer. All 3 of these patients had high-risk features preoperatively. In 1 patient, the pelvic lymph nodes were negative for metastatic prostate cancer. At 2-year follow-up, PSA level of this patient was undetectable.

Conclusions

Herein, we demonstrated that the PAFP contained lymph nodes in over 11% of the patients undergoing RARP at our institution. Prostate cancer was upstaged in 1 patient as a result of PAFP excision. Since this patient is free of biochemical recurrence at 2 years, routine excision and pathologic analysis of PAFP should be considered in prostate cancer patients undergoing radical prostatectomy.

Introduction

After radical prostatectomy in patients with prostate cancer [1], regional lymph node status is an important predictor of prognosis. Indeed, nodal status has significant implications for prognosis and management of these patients following radical prostatectomy. Currently, pelvic lymph node dissection (PLND) at the time of radical prostatectomy is the recommended procedure for staging prostate cancer because PLND is the most reliable method for determining the presence of nodal metastasis. In addition to the staging implications, PLND may provide valuable information needed for timing the initiation of additional therapies including adjuvant radiotherapy and androgen deprivation therapy [2]. Moreover, PLND may cure microscopic metastasis in selected patients [3].

Prostatic anterior fat pad (PAFP) refers to the adipose tissues located anterior to the prostate. Complete dissection and removal of PAFP has been traditionally advocated for better visualization of the anatomy, particularly the apex of the prostate, the anterior surface of the dorsal venous complex, and the puboprostatic ligaments [4], [5]. With better visualization of the apical anatomy, there is also a potential benefit of reducing the positive surgical margin rate at the apex [6]. Recently, PAFP has been reported to contain lymph nodes and that pathologic analysis of PAFP may yield a more accurate staging in patients with prostate cancer.

Over a 2-year period, we have performed PAFP excision during RARP in patients with prostate cancer in an effort to study the staging implications and the clinical significance of PAFP. We report that PAFP often contains lymph nodes, and that routine dissection and removal of AFP may benefit some patients with micrometastasis.

Section snippets

Patient selection

This study was approved by the Institutional Review Board at our institution, and patient data collection was done retrospectively. A total of 258 consecutive patients underwent PAFP excision during RARP procedure between July 2007 and June 2009. National Comprehensive Cancer Network (NCCN) guideline was used to determine the necessity of pelvic lymph node dissection. In addition, any patients with serum PSA level ≥10, biopsy Gleason scores ≥8, or clinical stage ≥T2b underwent standard pelvic

Results

Perioperative patient characteristics of 258 patients in this study are summarized in Table 1. Of these patients, 30 (11.6%) had 1 or 2 PAFP lymph nodes, whereas 228 (88.4%) men showed no lymphoid tissue in their PAFP. Preoperatively, mean PSA level was the only parameter with significant difference between the 2 groups: mean PSA level was 7.70 ng/ml in the former group and 6.01 ng/ml in the latter group (P = 0.039). All other preoperative and intraoperative parameters, including age, body mass

Discussion

Our data have demonstrated that in 258 patients who underwent RARP over a 2 year period, 11% contained PAFP lymph nodes and 3 were found to have metastatic prostate cancer. Of these latter 3 patients, 1 was upstaged as a result of the PAFP pathologic examination. These observations suggest that performing a thorough pathologic examination of PAFP may lead to a more accurate staging without additional morbidity.

Meticulous dissection of PAFP facilitates exposure of the bladder neck and prostatic

Conclusions

This study describes the benefit of PAFP dissection during radical prostatectomy in patients with prostate cancer. Overall, 30 of 258 patients (11.6%) were found to have lymph nodes within the PAFP, and 3 of these 30 men had lymph nodes positive for metastatic disease. In 1 patient with negative pelvic lymph nodes, prostate cancer was upstaged based on positive PAFP lymph nodes; this patient remains free of biochemical recurrence 2 years later. All 3 patients with positive PAFP lymph node had

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Cited by (19)

Presence of lymph nodes and metastasis within prostatic anterior fat pad in radical prostatectomy patients: A single Chinese institution experience and literature review
2023, European Journal of Surgical Oncology
Limited data from China, aim to investigate the incidence and the risk fctors of lymph node metastases in the prostatic anterior fat pad (PAFP).
Patients underwent radical prostatectomy (RP) were enrolled between March 2020 to December 2022 at a single institution. Separate pathological analysis of PAFP was performed within this area. Univariate analysis and Multivariate analysis were performed to determine the risk factor of PAFP metastasis.
A total of 255 patients were included. The study revealed an average age of 67.72 ± 7.07 years, with a mean total tumor volume of 41.54 ± 23.79 mL, and an average Pre-op PSA of 16.85 ng/mL. Clinical T stage was divided into T2, T3, and T4 (226, 25, 4 cases, respectively), while the Clinical M stage was categorized as M0 and M1 (248 and 7 cases, respectively). Out of the patients with PAFP, 19 (7.45 %) had lymph node in PAFP, and 3 (1.18 %) patients had metastases. In the univariate and multivariate analysis, Clinical M stage and anterior primary tumor were found to be a significant high-risk factor. Among the other 15 studies, six examined the risk factors associated with it, including anterior tumors, higher tumour volume, intermediate or high risk prostate cancer.
Due to the low proportion of lymph node involvement (7.45 %) and rare tumor metastasis (1.18 %), routine separate pathological analysis of PAFP is not recommended in all RP patients unless there are anterior tumors, higher tumor volume, or intermediate/high risk prostate cancer.
Re: Detailed analysis of patients with metastasis to the prostatic anterior fat pad lymph nodes: A multi-institutional study: I. Y. Kim, P. K. Modi, E. Sadimin, Y.-S. Ha, J. H. Kim, D. Skarecky, D. Y. Cha, C. O. Wambi, Y.-C. Ou, B. Yuh, S. Park, E. Llukani, D. M. Albala, T. Wilson, T. Ahlering, K. Badani, H. Ahn, D. I. Lee, M. May, W.-J. Kim and D. H. Lee J Urol 2013; 190: 527-534.
2014, Journal of Urology
Detailed analysis of patients with metastasis to the prostatic anterior fat pad lymph nodes: A multi-institutional study
2013, Journal of Urology
Citation Excerpt :
The most obvious benefit of removing and analyzing the PAFP is the increased accuracy of pathological staging. Published series of metastatic PCa to the PAFP lymph nodes after RP show a 1.2% to 2.5% prevalence rate.5–7 Consistent with those data, this series includes 8 centers with a PAFP lymph node metastasis rate of 0.5% to 2% and an overall 0.94% rate in the 4,261 patients who underwent RP.
Lymph nodes in the prostatic anterior fat pad rarely harbor metastatic disease. Therefore, the characteristics of patients with prostatic anterior fat pad lymph node metastasis are not well described in the literature. We identified the perioperative characteristics and assessed the clinical outcomes of patients with prostatic anterior fat pad lymph node metastasis.
At 8 tertiary care centers a total of 4,261 patients underwent complete removal and pathological analysis of the prostatic anterior fat pad. We describe preoperative and pathological characteristics, and clinical management and outcomes in patients with metastatic disease to the prostatic anterior fat pad.
Metastatic disease to the prostatic anterior fat pad lymph nodes was detected in 40 patients (0.94%), of whom 37 (92.5%) had intermediate or high risk features preoperatively. Most patients with prostatic anterior fat pad metastases underwent concomitant pelvic lymph node dissection, and adjuvant therapy with radiation, androgen ablation and/or chemotherapy. A total of 27 patients (67.5%) with prostatic anterior fat pad metastatic disease were up-staged as a result of prostatic anterior fat pad pathological analysis, of whom 14 (51.8%) remained free of biochemical recurrence with observation and/or definitive adjuvant/salvage therapy.
Most patients with prostatic anterior fat pad metastatic disease had intermediate to high risk features preoperatively. In some patients with such lymph node metastasis removing these lymph nodes resulted in prolonged biochemical recurrence-free survival. Therefore, we recommend that the prostatic anterior fat pad be removed in all patients undergoing radical prostatectomy. However, pathological analysis of the prostatic anterior fat pad may be limited to patients with intermediate to high risk oncological features preoperatively.
Massive pre-prostatic nodal metastasis from localized aggressive prostate cancer removed during robotic-assisted radical prostatectomy with extended pelvic lymph node dissection: a case report with brief literature review
2023, African Journal of Urology
Landscape and metastases of the lymph nodes in prostatic anterior fat pad at radical prostatectomy
2022, Zhonghua Wai Ke Za Zhi / Chinese Journal of Surgery
Anterior prostate fat resection during prostatectomy: a histopathologic review
2021, Journal of Robotic Surgery

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^☆: This work was supported in part by generous grants from the Tanzman Foundation, the Jon Runyan's Score for the Cure, and Korea Science and Engineering Foundation (KOSEF) grant funded by the Korean government (MEST) (no. R11-2008-014-00001-0).

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Original articleClinical—prostatePathologic implications of prostatic anterior fat pad☆

Abstract

Objective

Methods

Results

Conclusions

Introduction

Section snippets

Patient selection

Results

Discussion

Conclusions

Eur Urol

J Urol

Urology

Urology

Urology

J Urol

Urology

Original article
Clinical—prostate
Pathologic implications of prostatic anterior fat pad☆