Follow-up of Invasive Cancer of the Cervix In contrast, primary chemoradiotherapy is the treatment of choice for larger invasive cervical cancers (>4 cm) given their high likelihood of occult nodal metastases, locally advanced tumors invading the parametrium, lower one- third of the vagina, or adjacent pelvic organs, or those with known nodal or distant metastases (stages IB3, IIA2, IIB, III, and IVA, respectively) [2]. In this population, pretreatment imaging plays a critical role in radiation therapy treatment planning, specifically for contouring of the radiation field. CT Pelvis With IV Contrast Compared to MRI, CT provides very poor soft tissue characterization in the pelvis and therefore demonstrates a lower accuracy for the determination of local extent of invasive cervical cancer [9]. One multicenter study found that invasive cervical cancers, which appeared hypodense to the normal cervical stroma, were only well delineated in 35% to 73% of contrast-enhanced CT examinations [10]. Considering individual features, meta-analyses have shown CT with intravenous (IV) contrast to have 43% to 55% sensitivity and 71% specificity for parametrial invasion, and 41% sensitivity and 92% specificity for bladder invasion [11,12]. In comparison, MRI demonstrated 71% specificity (95% confidence interval [CI], 62%-79%) and 91% sensitivity (95% CI, 88%-93%) for parametrial invasion, and 84% sensitivity (95% CI, 57%-95%) and 95% specificity (95% CI, 87%-98%) for bladder invasion [12]. CT Pelvis Without and With IV Contrast CT pelvis without IV contrast provides very poor soft tissue characterization in the pelvis [13] and therefore is not useful for the evaluation of the local extent of invasive cervical cancer. The addition of noncontrast CT images would not appreciably add information to the contrast-enhanced CT evaluation.
Pretreatment Evaluation and Follow up of Invasive Cancer of the Cervix. Follow-up of Invasive Cancer of the Cervix In contrast, primary chemoradiotherapy is the treatment of choice for larger invasive cervical cancers (>4 cm) given their high likelihood of occult nodal metastases, locally advanced tumors invading the parametrium, lower one- third of the vagina, or adjacent pelvic organs, or those with known nodal or distant metastases (stages IB3, IIA2, IIB, III, and IVA, respectively) [2]. In this population, pretreatment imaging plays a critical role in radiation therapy treatment planning, specifically for contouring of the radiation field. CT Pelvis With IV Contrast Compared to MRI, CT provides very poor soft tissue characterization in the pelvis and therefore demonstrates a lower accuracy for the determination of local extent of invasive cervical cancer [9]. One multicenter study found that invasive cervical cancers, which appeared hypodense to the normal cervical stroma, were only well delineated in 35% to 73% of contrast-enhanced CT examinations [10]. Considering individual features, meta-analyses have shown CT with intravenous (IV) contrast to have 43% to 55% sensitivity and 71% specificity for parametrial invasion, and 41% sensitivity and 92% specificity for bladder invasion [11,12]. In comparison, MRI demonstrated 71% specificity (95% confidence interval [CI], 62%-79%) and 91% sensitivity (95% CI, 88%-93%) for parametrial invasion, and 84% sensitivity (95% CI, 57%-95%) and 95% specificity (95% CI, 87%-98%) for bladder invasion [12]. CT Pelvis Without and With IV Contrast CT pelvis without IV contrast provides very poor soft tissue characterization in the pelvis [13] and therefore is not useful for the evaluation of the local extent of invasive cervical cancer. The addition of noncontrast CT images would not appreciably add information to the contrast-enhanced CT evaluation.