Adjuvant therapy after primary surgery for stage I-IIA carcinoma of the cervix

Abstract

Radical hysterectomy and bilateral pelvic lymph node dissection is commonly used as a primary management option for treatment of stage IB/IIA carcinoma of the cervix. Overall cure rates approach 85%. However, a spectrum of relapse risk exists, depending on the presence or absence of primary tumor and nodal-related prognostic factors. Known factors include number and location of lymph nodes; size of primary, deep invasion in the cervix; capillary lymphatic space involvement; occult parametrial involvement; and positive or close surgical margins. Biologic determinants have yet to be identified. No systematic analysis has examined various combinations of prognostic factors to precisely define associated levels of risk and to predict the sites of relapse. Decreased local control and survival rates in some high-risk subgroups, usually those with nodal positivity, has led to the exploration of adjuvant therapies. Compiled data from retrospective series have defined the overall patterns of failure. Seventy-two percent of those relapsing have a component of pelvic failure, while 42% experience relapse in the pelvis alone. Fifty-eight percent have a component of distant failure but only 28% have distant disease alone. Adjuvant treatment options include pelvic radiotherapy, extended-field radiotherapy, chemoradiotherapy, and chemotherapy. Trials of adjuvant chemotherapy are too few to evaluate the use of available agents. Pelvic radiotherapy has been shown to reduce the relapse risk when surgical margins are close or positive. It also reduces the risk of pelvic relapse and improves the relapse-free interval but has no apparent impact on overall survival in the groups that have been selected for treatment. The apparent lack of benefit may relate to the choice of patients with nodal involvement who, despite high risk of pelvic failure, most likely have a predominant pattern of distant failure. Maximization of the survival benefit of pelvic radiotherapy requires the identification and treatment of the subgroup with a predominant pattern of pelvic failure, such as that examined in Gynecologic Oncology Group protocol 92. These may be patients with primary tumor-related, high-risk factors but negative nodes. Extended-field irradiation for microscopically involved para-aortic nodes provides a cure in 25%-40% of the patients. Further studies of prognostic factors and their relationship to sites of failure after surgery are necessary to define the benefits of currently available adjuvant therapies with respect to local control, survival, and quality of life, and also to direct future studies. New, effective systemic agents are required for those at high risk of developing distant disease.