To define the anatomical location of sentinel lymph nodes (SLN) in penile cancer patients based on Daseler's original zonal description using a combination of single photon emission computed tomography-computed tomography (SPECT-CT), cross sectional imaging and lymphoscintigraphy and characterise the limits of Zone V.
Patients with primary penile cancer ≥T1G2 were included in the study. A total of 113 groins with impalpable inguinal lymph nodes (cN0) underwent planar lymphoscintigraphy and SPECT-CT. The sentinel lymph nodes were mapped on cross sectional imaging according to Daseler's anatomical description. Using measurements from fixed anatomical landmarks, a custom-made software program mapped the SLNs. SLNs were mapped to the previously undefined Zone V using 3 approaches to avoid observational bias: (a) as perceived by the uroradiologist, (b) limiting Zone V to a 5 mm radius from the sapheno-femoral junction or (c) using a 10 mm radius from the sapheno-femoral junction.
Using SPECT-CT, drainage to the groins was seen in 109 of the 113 cN0 groins (96.5%). The majority of the SLNs were located in the central and superior quadrants with 38.2% lying within Zone I, 45% in Zone II and 13% in Zone V. More importantly, sentinel lymph nodes were still localised to the inferior zones with 3% located in Zone III and 0.8% in Zone IV.
Using a hybrid of SPECT-CT, cross sectional imaging and lymphoscintigraphy we have demonstrated that SLNs may be located in the inferior zones. We also define the limits of Zone V as an area of 5 mm radius from the sapheno-femoral junction.
Urologic oncology. 2018 Oct 12 [Epub]
Savvas Omorphos, Zia Saad, Alex Kirkham, Raj Nigam, Peter Malone, Jamshed Bomanji, Asif Muneer
Department of Urology, University College London Hospital, London NW1 2PG, UK., Institute of Nuclear Medicine, University College London Hospital, London NW1 2PG, UK., Department of Radiology, University College London Hospital, London NW1 2PG, UK., Department of Urology and NIHR Biomedical Research Centre University College London Hospital, London NW1 2PG, UK; Division of Surgery and Interventional Science, University College London, UK. Electronic address: .