Cervical cancer response to neoadjuvant therapy: MR imaging assessment.

PURPOSE: To determine the accuracy of magnetic resonance (MR) imaging in evaluating the invasive cervical carcinoma response to concurrent chemotherapy and radiation therapy. MATERIALS AND METHODS: MR imaging was performed before and after concurrent chemotherapy and radiation therapy in 18 patients with locally invasive cervical carcinoma. Surgery followed neoadjuvant therapy in all patients. The presence of a lesion, signal intensity, zonal anatomy integrity, vaginal and parametrial invasion, and lymph node enlargement was determined. Posttreatment MR and histopathologic findings were correlated. RESULTS: Fourteen patients had histopathologic confirmation of MR findings: Twelve had true-negative and two had true-positive findings. (Two had microscopic neoplastic foci beyond the spatial resolution of MR images; these foci do not change surgical treatment planning and probably do not influence prognosis. Therefore, these two patients were considered to have complete response). Four patients had false-positive findings; the hyperintense lesion on posttreatment MR images was due to a tunnel cluster pattern (focal hyperplasia of the endocervical glands with inflammation) in three patients and necrosis in one patient, without any evidence of neoplastic tissue. Thirty-three of 36 parametrial halves and 67 of 72 vaginal fornices were correctly interpreted on posttreatment images. Involvement of three parametrial halves and five fornices was overestimated at MR, because edema or inflammation was not distinguishable from tumor. CONCLUSION: MR imaging is 78% accurate in evaluation of tumor response; in 22% of patients, however, benign conditions were not distinguishable from tumor