The usefulness of MRI and PET imaging for the detection of parametrial involvement and lymph node metastasis in patients with cervical cancer.
OBJECTIVE
The purpose of this study is to elucidate the usefulness of magnetic resonance imaging (MRI) and positron emission tomography (PET) for the detection of parametrial involvement and lymph node metastasis in patients with cervical cancer.


METHODS
Thirty-six patients with cervical cancer were retrospectively enrolled. MRI and PET scans were performed for all patients within a week before radical surgery. The criterion for malignancy on MRI was >1 cm short axis diameter of the suspected lymph node. On PET, only fluorodeoxyglucose (FDG) uptake was significantly higher than the background and, if this FDG uptake showed on at least two consecutive axial slices, then the lesion was considered as a malignancy. We compared the extent of tumor on the surgical findings with the FIGO staging, MRI and PET scans.


RESULTS
The accuracy of FIGO and MRI staging was 67 and 84.4%, respectively. The accuracy for detecting pelvic lymph node metastasis was better for PET than for MRI (78 versus 67%, respectively). All FDG uptake lymph nodes were confirmed as metastatic lymph nodes by pathological evaluation; this included five lymph nodes <1 cm in diameter.


CONCLUSIONS
MRI provides an improved evaluation of local tumor extension, but PET is more useful for the evaluation of pelvic lymph nodes than MRI; however, PET still misses microscopic disease. Further studies are necessary to evaluate the usefulness of PET/computed tomography (CT) for the accuracy of the disease extension and the cost-effectiveness of MRI, PET or PET/CT in patients with cervical cancer.
Park
Won
W
Samsung Medical Center, Department of Radiation Oncology, Kangnam-ku, 135-710 Seoul, Korea.
Park
Young Je
YJ
Huh
Seung Jae
SJ
Kim
Byoung Gie
BG
Bae
Duk Soo
DS
Lee
Jeho
J
Kim
Bo Hyun
BH
Choi
Joon Young
JY
Ahn
Yong Chan
YC
Lim
Do Hoon
DH
D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000556:secondary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000473:pathology*
D019788:Fluorodeoxyglucose F18