The Revised FIGO Staging System for Uterine Malignancies: Implications for MR Imaging

Cancers of the uterine corpus and cervix are the most common gynecologic malignancies worldwide. The International Federation of Gynecology and Obstetrics (FIGO) staging system was first established in 1958, when it was recognized that the recurrence rate and patient outcomes were directly related to the degree of tumor spread at the patient's initial presentation. Changes in understanding of tumor biology led to a recent update in the FIGO staging system that reflects the variation in treatment strategies between endometrial and cervical cancer. Patients with endometrial cancer are primarily treated with hysterectomy; thus, staging is done at surgery and histologic analysis. Magnetic resonance (MR) imaging may accurately depict the extent of endometrial cancer at diagnosis and, in conjunction with the tumor grade and histologic subtype, help stratify risk, which determines the therapeutic course. Cervical carcinoma is staged at clinical examination because many tumors are inoperable at the time of patient presentation. Preoperative MR imaging criteria are not formally included in the revised FIGO staging system because cervical carcinoma is most prevalent in developing countries, where imaging resources are limited. However, MR imaging is highly sensitive and specific for depicting important prognostic factors and, when available, is recommended as an adjunct to clinical examination. The MR imaging findings of uterine carcinoma should be discussed in a multidisciplinary setting in conjunction with clinical and histologic findings, an approach that provides accurate staging and risk stratification and allows for individualized treatment.