Cervical Cancer

Cervical cancer is the third most common gynecologic malignancy and the eighth most common malignancy among women in the USA. The mean age for developing cervical cancer is about 50 yr; however, it can affect women as young as 20. About 1% of all cervical cancers occur in pregnant or recently pregnant women.

Cervical cancer is essentially a sexually transmitted disease. Risk is inversely related to age at first intercourse and directly related to the lifetime number of sexual partners. Risk is also increased for sexual partners of men whose previous partners had cervical cancer.

Human papillomavirus (HPV) infection and the development of cervical neoplasia are strongly associated. HPV infection is linked to all grades of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer. Infection with HPV types 16, 18, 31, 33, 35, and 39 increases the risk of neoplasia. However, other factors appear to contribute to malignant transformation. For example, cigarette smoking is associated with an increased risk of CIN and cervical cancer.

Pathology

Precursor cells (cervical dysplasia, CIN) develop into invasive cervical cancer over a number of years. CIN grades I, II, and III correspond to mild, moderate, and severe cervical dysplasia. CIN III, which includes severe dysplasia and carcinoma in situ, is unlikely to regress spontaneously and, if untreated, may eventually penetrate the basement membrane, becoming invasive carcinoma.
Squamous cell carcinoma accounts for 80 to 85% of all cervical cancers; adenocarcinomas account for most of the rest. Sarcomas and small cell neuroendocrine tumors are rare.

Invasive cervical cancer usually spreads by direct extension into surrounding tissues and the vagina or via the lymphatics to the pelvic and para-aortic lymph nodes drained by the cervix. Hematologic spread is possible.

Symptoms and Signs

CIN is usually asymptomatic and discovered because of an abnormal Pap smear. Patients with early-stage cervical cancer usually present with irregular vaginal bleeding, which is most often postcoital, but intermenstrual bleeding or menometrorrhagia may occur. Patients with larger cervical cancers or advanced-stage disease may present with foul-smelling vaginal discharge, abnormal vaginal bleeding, or pelvic pain. Obstructive uropathy, back pain, and leg swelling are manifestations of late-stage disease.

Diagnosis

More than 90% of early asymptomatic cases of CIN can be detected preclinically by cytologic examination of Pap smears obtained directly from the cervix. However, the false-negative rate is 15 to 40%, depending on the patient population and the laboratory. About 50% of patients with cervical cancer have never had a Pap smear or have not had one for >= 10 yr. The patients at higher risk for cervical neoplasia are the least likely to be tested regularly.