**4. What are the methods of surgical assessment?**

A definition of a pelvic node dissection (PND) is widely accepted in the gynaecological oncology literature [6]. PND includes bilateral removal of nodal tissue from the distal one-half of each common iliac artery, the anterior and medial aspect of the external iliac artery and vein to the level of the deep circumflex artery, and obturator fat pad anterior to the obturator nerve. The medial aspect of the dissection is the hypogastric artery. Enlarged nodes below the obturator nerve should also be removed. The obturator nerve should be identified and guarded prior to any sharp dissection. The nodes should be swept away from the nerve with careful attention paid to the area below the nerve to avoid damage to the numerous vessels present in this area. The ideal scenario is to remove the node in a single nodal unit to reduce 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 port or removed via the vagina if a hysterectomy is performed.

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

mesocolic lymph nodes within the sigmoid mesentery.

**3. Is histopathological type important?**

unilateral apparent stage 1 tumours.

262 Ovarian Cancer - From Pathogenesis to Treatment

enectomy in early mucinous cancers.

**4. What are the methods of surgical assessment?**

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

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

Over the last decade, the understanding of the pathogenesis of epithelial ovarian cancer has changed. The most common histopathological subtype, high-grade serous cancer (approximately 70–80% of cases) appears to arise in the distal fallopian tube [4]. Most of these women present with disease spread to the transperitoneal surfaces and to the lymph system. The majority of this chapter will be concerned with the role of lymphadenectomy in this group of women. Less common types of ovarian cancer include endometrioid, clear cell, low grade serous and mucinous tumours. These appear to have separate aetiologies with a different risk of lymphatic spread. The risk of nodal metastases appears to be lower in endometrioid and mucinous cancers. For example, a meta-analysis of 278 women with apparent early mucinous cancer of the ovary who underwent a full pelvic and para aortic nodal dissection reported an incidence of involved nodes of only 1.2% [5]. Most authors no longer recommend a lymphad-

A definition of a pelvic node dissection (PND) is widely accepted in the gynaecological oncology literature [6]. PND includes bilateral removal of nodal tissue from the distal one-half of each common iliac artery, the anterior and medial aspect of the external iliac artery and vein to the level of the deep circumflex artery, and obturator fat pad anterior to the obturator nerve. The medial aspect of the dissection is the hypogastric artery. Enlarged nodes below the obturator nerve should also be removed. The obturator nerve should be identified and guarded prior to any sharp dissection. The nodes should be swept away from the nerve with careful attention paid to the area below the nerve to avoid damage to the numerous vessels present in this area. The ideal scenario is to remove the node in a single nodal unit to reduce 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 tissue including the dorsal surfaces of the vessel (**Table 1**).

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

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).


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