Date Published: October 25, 2011
Publisher: Hindawi Publishing Corporation
Author(s): João Paulo Martins de Carvalho, Bruno F. Patrício, Jorge Medeiros, Francisco J. B. Sampaio, Luciano A. Favorito.
Objectives. To provide a better understanding of the distribution of inguinal nodes in order to prevent the complications of unnecessary and extended dissections in penile cancer.
Methods. The bilateral inguinal regions of 19 male cadavers were dissected. Nodal distribution was noted and quantified based on anatomical location. The superficial nodes were subdivided into quarters as follows: superomedial, superolateral, inferomedial, and inferolateral. Statistical analysis was performed comparing node distribution between quarters using one-way analysis of variance (ANOVA), and the unpaired T-test was used between superficial and deep nodes.
Results. Superficial nodes were found in all inguinal regions studied (mean = 13.60), and their distribution was more prominent in the superomedial quarter (mean = 3.94) and less in the inferolateral quarter (mean = 2.73). There was statistical significance between quarters when comparing the upper group with the lower one (P = 0.02). Nodes were widely distributed in the superficial region compared with deep lymph nodes (mean = 13.60 versus 1.71, P < 0.001). Conclusions. A great number of inguinal lymph nodes are distributed near the classical anatomical landmarks for inguinal lymphadenectomy, more prominent in upper quadrants.
Penile cancer is an aggressive and mutilating disease that deeply affects the patient’s self-esteem. Penile cancer is a rare neoplasia, particularly in developed countries. One of the world’s highest prevalence rates is found in India, at 3.32 per 100,000 inhabitants, and the lowest incidence is among Jewish men born in Israel, with rates close to zero . In the United States, the prevalence is 0.2 cases for each 100,000 inhabitants, whereas in Brazil, the national incidence of penile cancer 4.6 per 100,000 inhabitants (with a wide variation of 2.9 to 6.8 cases per 100,000 depending on the region), one of the world’s highest rates of this neoplasia [2, 3].
The present work was approved by the bioethics committee of our institution and was in accordance with the ethical standards of the committee on human experimentation. From May 2010 to March 2011, we analyzed 19 fresh cadavers (38 inguinal regions) from males aged 23 to 53 years old (mean = 32) who had been submitted to dissection of the inguinal region. All cadavers were obtained through donations from the university, and none of the decedents were trauma victims.
The dissections preserved the saphenofemoral junction and all the tributaries of the saphena magna vein, which permitted adequate visualization of the nodes and their classical anatomical landmarks (Figure 2).
Penile lymphatic drainage parallels venous drainage, with a superficial system that drains the skin and a deeper system that drains the glans and corporal bodies. The superficial inguinal nodes are located just below the inguinal ligament and extend trough 4-5 cm of the saphenous hiatus. They are distributed in quarters set from the anastomosis between the saphena magna and femoral veins . The deeper inguinal nodes are located just below the fascia lata and medially to the saphena vein. Although small in number, these nodes are of extreme importance, since their venous drainage occurs through the superficial iliac veins [8, 9].
Our group confirmed that a great number of inguinal lymph nodes are distributed near the classical anatomical landmarks for ILND, as superficial and deeper femoral veins, inguinal ligaments, and fascia lata. The nodes were more prominent in the upper quadrants of the superficial inguinal lymph nodes. When performing prophylactic ILND using these criteria, less extensive surgery should be performed, with adequate node resection, including the superficial and deeper groups.