Editing EAU & ASCO: Penile Cancer 2023 (section)

==== Clinically node-negative patients (cN0) ====

* '''<span style="color:#ff0000">≈20-25% of cN0 patients may harbour occult metastases''' 
** '''<span style="color:#ff0000">Additional staging is warranted'''
** initial LN staging is focused on identifying (micro)metastatic disease in the inguinal LNs as early as possible

===== Staging in cN0 =====

====== Indications ======

*'''<span style="color:#ff0000">Recommended'''
** '''<span style="color:#ff0000">High-risk tumors: T1b or higher'''
* Optional for intermediate-risk (pT1a G2)
** Surveillance is an alternative to surgical staging in patients willing to comply with strict follow-up

====== Options ======

* '''<span style="color:#ff0000">Surgical staging'''
** '''Invasive/surgical staging remains indispensable to identify micro-metastasis before nodal metastases become palpable/visible.'''
** '''<span style="color:#ff0000">Approaches (2)'''
**# '''<span style="color:#ff0000">Dynamic sentinel node biopsy (DSNB) (preferred)'''
**#* '''A sentinel node (SN) is defined as the first LN on a direct drainage pathway from the primary tumour.'''
**#** Based on this concept, it is assumed that if the SN is negative, this indicates the absence of lymphatic tumour spread in the corresponding inguinal basin.
**#** If histopathology identifies SN (micro)metastasis, ipsilateral completion ILND is indicated
**#* Test characteristics
**#** Sensitivity 92–96% (in experienced centres)
**#** False negative rates 4–8% (in experienced centres)
**#* '''Technique'''
**#** '''Inguinal US is obtained prior to DSNB'''
**#*** If sonographically suspicious nodes are detected, fine needle aspiration cytology (FNAC) can easily be performed in the same session to confirm the diagnosis of inguinal LN metastasis
**#**** if US + FNAC is positive, it can reduce the need for DSNB and allow for additional staging and therapeutic LN dissection at an earlier stage
**#*Adverse events
**#**Complication rate 6–14% (in experienced centres)
**#***Developed to avoid resecting unnecessary LNs and thereby minimizing the morbidity of surgical staging
**#*'''If DSNB is not available, and referral to a centre with experience with DSNB is not feasible, or if the patient does not want to run the risk of a false-negative procedure, ILND (modified/superficial/video-endoscopic) can be considered after informing the patient of the inherent risk of higher morbidity associated with these procedures.'''
**# '''<span style="color:#ff0000">Inguinal lymph node dissection (ILND)'''
**#* '''Radical inguinal lymph node dissection (ILND)''' 
**#** Most accurate surgical staging method
**#** Associated with the highest complication rates
**#* '''Modified ILND'''
**#** Lowers morbidity 
**#** Maintains sufficient sensitivity
**#** Modifications in modified ILND
**#**# Shorter skin incision
**#**# No dissection lateral to the femoral artery
**#**# No dissection caudal to the fossa ovalis
**#**# Preservation of the saphenous vein
**#*'''Video-endoscopic/robot-assisted radical LND'''
**#**Introduced more recently
**#**Similar lymph node yield compared to open
**#**Reduces wound-related complications compared to open ILND, but no significant reduction in lymphatic complications
**#***Main predictor of lymphatic complications is the number of lymph nodes removed
* '''<span style="color:#ff0000">Non-surgical staging'''
** '''<span style="color:#ff0000">Imaging'''
*** '''<span style="color:#ff0000">Not reliable to evaluate clinically node-negative patients'''
**** Conventional imaging modalities such as US, computed tomography (CT) or MRI cannot detect micrometastases
****18F-fluoro-2-deoxy-D-glucose positron emission tomography (18FDG-PET) does not detect LN metastases < 10 mm
****These imaging modalities can be of value to detect enlarged/abnormal nodes in patients when physical examination is challenging (e.g., due to obesity).