MRI reporting guidelines for cervical cancer help maintain uniformity of reports and assessment of important imaging staging criteria.
The tumour should be measured in three orthogonal planes. Tumours with a maximum diameter >4 cm are usually not amenable to primary radical surgery.
The parametrium is the anatomical space lateral to the cervix. The reported accuracy of MRI in detecting parametrial invasion varies in the literature from 76 to 92% 2.
MRI does however have a high negative predictive value in excluding parametrial invasion. If the T2 hypointense cervical ring is intact, then parametrial invasion is unlikely.
Replacement of the usual hypointense vaginal wall with hyperintense tumour:
- invasion of the upper 2/3 of the vagina: stage IIa
- invasion of the lower 1/3 of the vagina: stage IIIa
Pelvic sidewall involvement or hydronephrosis
Extension to the pelvic sidewall and or hydronephrosis (unless due to another cause) is consistent with IIIb disease.
Bladder and rectal invasion
MRI has a high negative predictive value at excluding bladder and rectal involvement.
Bladder involvement can be seen on MRI as thickening of the posterior bladder wall and disruption of the hypointense bladder musculature or a mass within the bladder.
Rectal involvement is less common and can be seen as loss of posterior fat planes and direct tumour extension.
- 1. Kaur H, Silverman PM, Iyer RB et-al. Diagnosis, staging, and surveillance of cervical carcinoma. AJR Am J Roentgenol. 2003;180 (6): 1621-31. AJR Am J Roentgenol (full text) - Pubmed citation
- 2. Nicolet V, Carignan L, Bourdon F et-al. MR imaging of cervical carcinoma: a practical staging approach. Radiographics. 2000;20 (6): 1539-49. doi:10.1148/radiographics.20.6.g00nv111539 - Pubmed citation