**2. The lymphatic drainage of the ovaries**

An understanding of the lymphatic drainage of the ovary and fallopian tube is important in the management of women with ovarian cancer. There are three main lymphatic pathways. The principal pathway is along the ovarian vessels through the infundibulopelvic ligament to the para aortic and para caval nodes surrounding the aorta and inferior vena cava (IVC). The second pathway occurs through the broad ligaments into the pelvic nodal region. Of note, spread to contralateral pelvic nodes in women with a unilateral cancer is reported in up to 30% of women [3]. Therefore, a bilateral pelvic node dissection (PND) is recommended even with unilateral apparent stage 1 tumours.

the risk of nodal fracture leading to possible tumour dissemination and port site metastases. A PND may be performed either as an open procedure or as part of a laparoscopic procedure. Laparoscopic surgery lends itself to PND due to the increased magnification and illumination of the surgical field and dissected nodes can be removed through an 11/12 mm suprapubic

The Role of Lymphadenectomy in Ovarian Epithelial Cancer

http://dx.doi.org/10.5772/intechopen.72702

263

Para aortic assessment/dissection has in contrast to pelvic nodes not been well quantified. Pomel et al. [7] have published a proposed classification of para aortic node assessment which ranges from radiological assessment and palpation to a full systematic dissection of all nodal

Open para aortic dissection (type A1 to B1) requires a generous midline abdominal incision to the xiphisternum and a self-retaining retractor to allow access to the great vessels. The right side of the colon and small bowel are mobilised by incising the peritoneum at the level of the right common iliac artery extending medially and caudally to the fourth part of the duodenum and then incising the peritoneum along the right paracolic gutter to the hepatic flexure. This allows the surgeon to perform called 'Kocher manoeuvre' mobilising the bowel off both the right renal fascia and ureter and to be retracted out of the abdomen. Following this, the surgeon should identify the left ureter lying medially underneath the inferior mesenteric vein. The node dissection should not start until all the important anatomical structures

Laparoscopic PA node dissection is well described in the literature and can be performed either via the conventional transperitoneal route or via an extra peritoneal route. Both routes require a high degree of laparoscopic training and is considered unlikely to replicate a systematic node dissection (Pommel type A) but rather an extensive node sampling (Pommel type B1–2).

A1 Complete (includes infrarenal and suprarenal up to coeliac trunk to midpoint of common iliac vessels)

B1 Extensive (incudes para aortic areas, but does not allow full visualisation of structures—adventicia of vessels. Renal vessels, anterior common vertebral ligament, psoas muscle and sacrum B2 Minimal (includes limited para aortic areas, and does not allow visualisation of structures above)

A3 Infra inferior mesenteric artery (IMA) (as above but does not include dissection above IMA)

port or removed via the vagina if a hysterectomy is performed.

tissue including the dorsal surfaces of the vessel (**Table 1**).

have been identified including the inferior mesenteric artery (IMA).

A2 Infrarenal (as above, but does not include suprarenal dissection)

C1 Palpation (direct) following full exposure of PA area C2 Palpation (indirect), transperitoneal without any exposure

**Table 1.** Proposed classification of para aortic node assessment (Pomel et al. [7]).

C3 Radiological assessment by PET/CT or MRI

**A Systematic para aortic node dissection**

**B Para aortic sampling**

**C Non-excisional assessment**

**Type**

A third lesser route is through the uterine round ligament to the inguinal nodes. In addition, women with disease involving the rectum or sigmoid colon may have tumour spread to the mesocolic lymph nodes within the sigmoid mesentery.
