16 Cervix Carcinoma

302 Cervix Cancer

2 Anatomical Topography The uterus is located in the central part of the pelvis between the bladder and rectum. It is divided into the corpus and cervix and is connected to the pelvis by the parametria and by the sacro-uterine ligaments to the sacrum. Only the posterior part of the cervix is covered by peritoneum (pouch of Douglas). All these structures are directly accessible per vaginam and per rectum through the pouch of Douglas. The typical position of the uterus is anteversion and anteflexion, but it may also be straight or retroflected. The cervix has a central orifice (the external os) with an anterior and a posterior lip, and an internal orifice (isthmus) with the endocervical canal between the two. The diameter of the cervix varies between 2 and 5 cm, with a width of 2.5 - 5 cm and a thickness of 2 - 4 cm. The length varies between 2 and 5 cm (as the length of the endocervical canal). The length of the uterine cavity varies somewhere between 4 and 10 cm. The main regional lymph nodes are parametrial and then iliac, presacral and para-aortic; involvement of the para-aortic node is considered as distant metastasis. The whole uterus including the cervix and the vaginal wall are densely vascularized and their tolerance to radiation is very high. In contrast, critical organs which are directly adjacent to the cervix like the rectum and bladder are more radiosensitive. In some cases, the very radiosensitive small or large bowel (sigmoid) may be in direct contact to the uterine wall as well. The vagina must also be considered as an organ at risk. Pathology Squamous cell carcinomas represent 80 - 90% of all cervical cancer. Adenocarcinoma is the second most frequent histological subtype and usually originates from the endocervix (5). It usually occurs in young women. The prognosis of cervical adenocarcinoma compared with squamous cervical carcinoma is controversial. Rare forms like mesonephroid adenocarcinoma, adenosquamous carcinoma and undifferentiated carcinoma, or glassy cell tumors are generally considered to have a worse prognosis. If there is concomitant endometrial invasion, the survival rate is significantly lower. Different macroscopic forms are described: exophytic, ulcerative, infiltrating, which most often present in combination. There are different patterns of local spread (FIGO staging) (33) (see Appendix). Work Up Gynecological examination remains the essential part of tumour assessment. It is carried out jointly by the gynecological surgeon and the radiation oncologist, under general anesthesia if necessary. The pelvic examination starts with the inspection of the external genitalia, the uterine portio and the vaginal walls. If possible, the uterine cavity is probed with a semiflexible hysterometer to measure the length of the uterine cavity. Next, bimanual abdominovaginal and abdominorectal examination is performed (right hand right pelvis, left hand left pelvis). The pelvic examination is completed by a bidigital rectovaginal examination (bimanual). 3 4