Accuracy of magnetic resonance imaging in predicting residual disease in patients treated for stage IB2/II cervical carcinoma with chemoradiation therapy: Correlation of radiologic findings with surgicopathologic results

BACKGROUND. The evaluation of residual disease (RD) after chemoradiation therapy (CRT) in stage IB2/II cervical carcinoma conventionally is based on a clinical examination and magnetic resonance imaging (MRI) performed 3 to 8 weeks after the end of treatment. Very few studies have correlated MRI and histologic findings specifically in cervix cancer. This was the objective of the current study. METHODS. A retrospective review was undertaken of patients who fulfilled the following inclusion criteria: 1) stage IB2/II cervical cancer, 2) external radiotherapy (45 grays [Gy]) was given with concomitant chemotherapy followed by uterovaginal brachytherapy (15 Gy), 3) MRI studies were obtained between 3 weeks and 8 weeks after brachytherapy, and 4) completion surgery included at least a hysterectomy. Postsurgical histologic findings and MRI results were compared. RESULTS. Forty-four patients who were treated between 2003 and 2006 fulfilled all inclusion criteria. Twelve patients (27%) had achieved a radiologic complete response, 16 patients (36.5%) had unclassified lesions (RD or 'fibrosis'), and 16 patients (36.5%) had radiologic residual tumor. According to the histologic results, 19 patients (43%) had no RD, 10 patients (23%) had inframillimeter RD, 2 patients (5%) had RD that measured <1 cm, and 13 patients (29%) had RD that measured >1 cm. The sensitivity and specificity of MRI in evaluating RD were 80% and 55%, respectively. CONCLUSIONS. The current results indicated that the evaluation of RD 3 to 8 weeks after CRT with MRI is difficult, and the risk of false-positive results is high. Another radiologic procedure or a more technologically advanced MRI technique, such as diffusion-weighted MRI, should be evaluated.