cervical cancer, 5-year survival is 58% for those with parametrial invasion (stage IIB), 16% for patients with infiltration of pelvic organs (IVA), and 15% when distant metastases (IVB) are present. Patients with negative lymph nodes have a 5-year survival rate of 90% as opposed to 60–20% for patients with lymph node metastases. Tumor extension to para-aortic lymph nodes reduces survival by half. For instance, the 5-year survival rate of stage IB decreases from 85% to 50–60% in patients with pelvic lymph node metastases and to only 25% in patients with para-aortic lymph nodes (Kosary 2007; Tewari et al. 2014).

The prognosis for patients with recurrent cervical carcinoma is reported to be less than 10% but there are subgroups of patients with markedly better prognosis. Five-year survival rates range from 30 to 70% in patients with curative pelvic exenteration for central tumor recurrence (Brenner 2002; Sant et al. 2001). Similar survival rates of 40–70% are reported for curative radiotherapy of recurrent cervical carcinoma in patients not having undergone primary radiation therapy. However, the prognosis strongly depends on the size of the recurrent tumor and its location. Recurrent tumor in the pelvic sidewall is associated with a disease-free 5-year survival rate of 20–50%, which is below that of central tumor recurrence (Hille et al. 2003).

2\ Imaging

2.1\ Indications

Currently, MRI is recommended for pretreatment assessment of local tumor extent in patients with histologically proven FIGO stage IB or greater (Balleyguier et al. 2011). It provides relevant information for deciding between primary operation and radiotherapy. It is the method of choice for local tumor staging: assessing the depth of infiltration, tumor volume, and involvement of adjacent structures. The clinical examination is inadequate to exclude parametrial invasion and infiltration of the urinary bladder and rectum while the extent of vaginal involvement can be determined more reliably by means of colposcopy. MRI is the most accurate imaging modality (90%) for distinguishing cancer confined to the cervix from

cancer with parametrial infiltration (stage IB from IIB). A recent meta-analysis of the available literature on the diagnostic performance of clinical examination and MRI in detecting parametrial invasion and advanced-stage disease (FIGO stage ≥IIB) revealed a pooled sensitivity of 40% (95% CI 25–58) for the evaluation of parametrial invasion with clinical examination comparing with 84% (95% CI 76–90) with MRI and 53% (95% CI 41–66) for the evaluation of advanced disease with clinical examination as opposed to 79% (95% CI 64–89) with MRI (Thomeer et al. 2013). Conventional radiologic modalities such as cystoscopy, rectosigmoidoscopy, or double-contrast barium enema, as recommended in the FIGO classification, have been abandoned in most cases since MRI has become firmly established as the first-line modality for evaluating the local extent of cervical cancer. MR urography has also replaced conventional IV urography, which used to be the standard procedure in patients with advanced or recurrent cervical cancer and clinically suspected urinary obstruction. In this way, MRI evaluation of cervical cancer is even cost effective (Hricak et al. 1996). Cervical cancer of stages 0 (carcinoma in situ) and IA (microinvasive cervical cancer) cannot­ be assessed directly by MRI or CT. Nevertheless, in clinical practice, pelvic MRI could be performed for pretherapeutic evaluation of the pelvic organs and for radiologic lymph node staging at these early stages as well. Most patients already have a histologic diagnosis of cervical cancer at the time of the exam. This means that MRI is performed to evaluate the extent of the cervical carcinoma and not to detect it.

MRI is considered the best method for planning radiochemotherapy and for following up tumor response to therapy. Pelvic CT scanning is the established technique for planning radiotherapy in cervical cancer.

In the aftercare of patients, MRI can distinguish postoperative scar formation or postactinic changes from recurrent tumor after about 6 months, and guidelines also recommend pelvic MRI in patients with suspected recurrence of cervical cancer.

With its lower soft-tissue contrast, CT is widely less used for assessing the local extent of cervical cancer.

2.1.1\ Role of CT and MRI

The most important advantages of multislice CT over MRI are the shorter examination time and the high spatial resolution. Reported staging accuracy for computed tomography ranges from 32 to 80% in literature. The major drawback of CT is the markedly poorer soft-tissue contrast compared with MRI and the resulting inadequate differentiation between tumor and normal cervical stroma or parametrial structures (Fig. 5). The sensitivity for parametrial invasion ranges from 17 to 100%, with an average of 64%. Specificity ranges from 50 to 100%, with an average of 81%. Hence, the diagnostic accuracy of CT is inadequate for the detection of small cervical cancers and early parametrial infiltration, having only a minor role in the local staging (Brenner et al. 1982; Villasanta et al. 1983; Tsili et al. 2013; Hricak et al. 2005). Unenhanced CT identifies tumors only indirectly as cervical enlargement, while tumors are depicted after contrast medium administration as contrast-enhancing lesions. Parametrial infiltration is detected indirectly by an irregular cervical demarcation or larger intraparametrial lesions. CT depicts rectal or bladder infiltration only indirectly as consumption of the fat lamella or in advanced tumor stages when there is wall thickening or a tumoral mass protruding into the lumen. In cases where pelvic CT is performed, combined oral and rectal contrast medium administration is recommended.

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On the other hand, CT is the method of choice for excluding pulmonary metastases, which is the reason why guidelines in Germany recommend a chest CT scan for patients with FIGO stage III or IV (Schmidt-Matthiesen and Wallwiener 2005). CT of the chest is performed with IV contrast administration and including the supraclavicular lymph nodes. Finally, CT can be used as an alternative modality for lymph node staging and liver imaging and is indicated for evaluating the extent of osseous damage in patients with bone metastases.

With its excellent soft-tissue contrast on T2-weighted images, MRI is the imaging modality of choice for assessment of cervical cancer. This is ensured by multiplanar capabilities of imaging planes and imaging in two planes (Table 3) (Hricak et al. 1988; Kim and Han 1997), allowing optimal adjustment to pelvic

Table 3  Sensitivity and specificity of MRI in pretreatment staging of cervical cancer

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