Mapping of pelvic lymph node metastases in prostate cancer.
BACKGROUND
Opinions about the optimal lymph node dissection (LND) template in prostate cancer differ. Drainage and dissemination patterns are not necessarily identical.


OBJECTIVE
To present a precise overview of the lymphatic drainage pattern and to correlate those findings with dissemination patterns. We also investigated the relationship between the number of positive lymph nodes (LN+) and resected lymph nodes (LNs) per region.


METHODS
Seventy-four patients with localized prostate adenocarcinoma were prospectively enrolled. Patients did not show suspect LNs on computed tomography scan and had an LN involvement risk of ≥ 10% but ≤ 35% (Partin tables) or a cT3 tumor.


METHODS
After intraprostatic technetium-99m nanocolloid injection, patients underwent planar scintigraphy and single-photon emission computed tomography imaging. Then surgery was performed, starting with a sentinel node (SN) procedure and a superextended lymphadenectomy followed by radical prostatectomy.


METHODS
Distribution of scintigraphically detected SNs and removed SNs per region were registered. The number of LN+, as well as the percentage LN+ of the total number of removed LNs per region, was demonstrated in combining data of all patients. The impact of the extent of LND on N-staging and on the number of LN+ removed was calculated.


CONCLUSIONS
A total of 470 SNs were scintigraphically detected (median: 6; interquartile range [IQR]: 3-9), of which 371 SNs were removed (median: 4; IQR: 2.25-6). In total, 91 LN+ (median: 2; IQR: 1-3) were found in 34 of 74 patients. The predominant site for LN+ was the internal iliac region. An extended LND (eLND) would have correctly staged 32 of 34 patients but would have adequately removed all LN+ in only 26 of 34 patients. When adding the presacral region, these numbers increased to 33 of 34 and 30 of 34 patients, respectively.


CONCLUSIONS
Standard eLND would have correctly staged the majority of LN+ patients, but 13% of the LN+ would have been missed. Adding the presacral LNs to the template should be considered to obtain a minimal template with maximal gain. NOTE: This manuscript was invited based on the 2011 European Association of Urology meeting in Vienna.
Department of Urology, University Hospitals Leuven, Leuven, Belgium. steven.joniau@uzleuven.be
Steven
S
Joniau
Laura
L
Van den Bergh
Evelyne
E
Lerut
Christophe M
CM
Deroose
Karin
K
Haustermans
Raymond
R
Oyen
Tom
T
Budiharto
Filip
F
Ameye
Kris
K
Bogaerts
Hein
H
Van Poppel
D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000556:secondary* / Q000601:surgery; D000328:Adult; D000368:Aged; D006801:Humans; D008207:Lymphatic Metastasis; D008208:Lymphatic System / Q000473:pathology* / Q000601:surgery; D061305:Lymphoscintigraphy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010388:Pelvis / Q000473:pathology*; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology* / Q000601:surgery; D012307:Risk Factors; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods