Groin Dissection
Kenneth D. Hatch
GENERAL PRINCIPLES
Groin dissection is indicated when the risk of metastasis to the groin is sufficient. This means all lesions are with more than 1-mm invasion or greater than 2 cm in size.
Definition
Superficial inguinal dissection is removal of inguinal nodes ventral to the fascia lata and cribriform fascia over the fossa ovalis.
Inguinal-femoral node dissection includes the above plus removing the few lymph nodes medial to the femoral vein and into the external inguinal ring. The most cephalad of these nodes is the Cloquet node.
Anatomic Considerations
The superficial nodes are located between Camper fascia and the fascia lata which cover the femoral vessels. They are oriented in vertical and horizontal groups.
It is important to preserve the subcutaneous tissue between the skin and Camper fascia to prevent skin necrosis.
The fascia lata is left intact over the quadriceps muscle and femoral vessels until the entry of the saphenous vein into the femoral vein at the fossa ovalis.
The superficial epigastric, external pudendal, and circumflex iliac vessels will be encountered exiting the fascia over the femoral vessels.
The deep femoral nodes are located medial to the femoral vein and can be dissected without opening the femoral sheath to expose the femoral artery and vein.
Nonoperative Management
Large, fixed, and/or ulcerated nodes are best treated with radiation therapy with radiation-sensitizing doses of chemotherapy. All other nodes should be removed and postoperative radiation therapy based on pathology findings.
Imaging and Other Diagnostics
PET/CT is useful in detecting systemic disease as well as pelvic node metastases.
MRI is most accurate in detecting the size and extent of primary lesions and is 85% accurate in detecting lymph node metastases.
PREOPERATIVE PLANNING
Patient counseling will be most important. The patient should be counseled that the treatment will cause a significant change in their body image. All lesions greater than 2 cm or more than 1 mm of invasion will undergo ipsilateral femoral node dissection.
If the lesion involves a structure within 1 cm of a midline structure, then bilateral dissection should be performed.
If ipsilateral nodes are positive, contralateral nodes will be dissected.
Patients with enlarged palpable nodes should have imaging to define the extent of the disease, then if resectable, bilateral removal of large suspicious nodes is advised. Further surgery will be dictated by frozen section. It could include bilateral complete inguinal femoral node dissection or it may be removal of positive nodes and postoperative radiation therapy.
Enlarged pelvic nodes found on imaging may be resected.
There should be a discussion about the high risk of leg edema.
A bowel prep is not routinely performed. However, those patients that will have extensive surgery around the anus or have tissue flaps for reconstruction should take a liquid diet for 24 hours before surgery and an oral cathartic the afternoon before surgery. This will delay bowel movements and decrease the risk of infection.
Antibiotics will begin prophylactically and then redosed after 4 hours of surgery.
SURGICAL MANAGEMENT
Positioning
Lithotomy with leg support.
Approach
Inguinal femoral nodes first, then radical vulvectomy.
PROCEDURES AND TECHNIQUES
Left Groin Lymph Node Dissection
Camper fascia is incised and preserved.
Identifying the blood vessels
The superficial inferior epigastric, lateral circumflex iliac, and the external pudendal will be ligated (Tech Fig. 3.1).
The saphenous vein should be identified at its location in the distal point of the femoral triangle. It may be preserved if there are no positive nodes.
There may be an accessory saphenous vein as well.
Tech Figure 3.1. Anatomy of the right groin.
Stay updated, free articles. Join our Telegram channelFull access? Get Clinical TreeGet Clinical Tree app for offline access |