About 6 to 10 aortic nodes are located to the left, anterior and posterior to the aorta. As noted in Figure 1, three para-aortic node chains exist. However, cervical cancer can occasionally metastasize directly to the para-aortic nodes by embolization through the posterior trunks. Para-aortic nodal spread is usually by an orderly, progressive involvement of the pelvic and common iliac nodes. The three para-aortic lymph node chains are illustrated: the left aortic chain (I) lies to the left of the aorta, the aortocaval nodes (II) lie between the aorta and vena cava, and the caval chain (III) lies to the right of the vena cava. The anterior channels (C) pass behind the bladder and terminate predominantly in the external iliac lymph nodes the posterior lymphatic channels (A) course posteriorly and caudad in the uterosacral ligaments before turning cephalad and terminating in the common iliac, subaortic, para-aortic, and superior rectal lymph nodes. In addition to the lateral lymphatic trunks, smaller but consistent anterior and posterior lymphatic trunks are present. The major lymphatic drainage of the cervix is through the lateral channels (B) to the external iliac, hypogastric, obturator, and common iliac lymph nodes. Posterior channels drain directly into the common iliac and para-aortic nodes and superior rectal nodes.įig. 3 Also, small anterior channels pass behind the bladder and terminate in the external iliac nodes. These course through the parametria and drain to the external iliac, hypogastric, obturator, and common iliac nodes (Fig. The lymphatic channels draining the cervix converge to form lateral trunks. It is more likely to occur with large-volume tumors and if several lymphatic spaces are involved. If these spaces are involved, lymphatic embolization to regional lymph nodes can occur. Lymphatic spaces are present within 1 to 2 mm of the basement membrane. 2 The obstruction usually occurs in the distal third of the ureter. About one third of patients with stage IIIB cancers have ureteral obstruction, and about 5% have bilateral obstruction. The anatomic position of the ureter (within 2 cm of the uterine cervix) makes the ureter vulnerable to involvement. Lateral spread to the parametria mandates some type of radiologic evaluation of the ureters. As will later be enumerated, most traditional testing can be avoided in early-stage diseases, particularly when operative intervention is planned. These observations are important in the decision to order expensive tests in this era of cost containment. Anterior spread to the bladder is unusual in the absence of large-volume tumors with parametrial extension. Rectal spread is usually associated with posterior vaginal involvement. It may spread posteriorly to involve the rectum or the uterosacral ligaments. Another common pattern of spread is distal, to involve the vaginal fornices and later (and with larger-volume tumors) the midportion and distal third of the vagina. In this scenario, the cardinal ligaments eventually are involved. If the basement membrane is intact and stromal invasion is absent, dissemination and metastases do not occur.Ĭervical cancer usually extends by lateral spread to involve the parametria, following a path of least resistance. The progression of squamous cell neoplasias to invasive carcinomas was addressed in earlier chapters. Hematogenous dissemination usually occurs with more advanced disease or unusual cell types, such as adenosquamous or neuroendocrine tumors. Traditional and more modern pretreatment diagnostic modalities will be explored.ĭirect local extension and lymphatic embolization are the primary routes of spread of cervical carcinoma. ![]() The purpose of this chapter is to review the usual patterns of spread of cervical cancer. Although workup and studies are indicated for all patients with clinically advanced disease, immunocompromised patients should have extensive workups before treatment modalities are chosen. ![]() These patients include those with immunocompromised states, such as renal transplant patients or those who test positive for HIV on serum testing. However, at the outset, it should be emphasized that a subgroup of patients with invasive cervical cancer are at greater risk for a more aggressive cervical cancer and for more advanced stage. 1 The epidemiology of this disease was reviewed in an earlier chapter. In 2001, an estimated 12,900 cases of invasive cervical cancer will have occurred in the country, and more than 4,400 women will have died from cervical cancer. Although surveillance with cervical cytologic smears has resulted in a significant decrease in deaths from invasive cervical cancer in industrialized nations, a significant number of women continue to develop advanced carcinoma of the cervix each year in the United States.
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