Signal characteristics of tumors shown by high-resolution endorectal coil magnetic resonance imaging may predict outcome among patients with cervical carcinoma treated with irradiation. A preliminary study.
BACKGROUND
The purpose of this study was to evaluate the role of high-resolution magnetic resonance imaging with the endorectal coil (eMRI) in the management of cervical carcinoma treated with definitive irradiation.


METHODS
Eighteen patients with invasive cervical carcinoma (International Federation of Gynecology and Obstetrics Stages Ib-IIIb) consented to evaluation with eMRI on a 1.5 tesla system with high resolution (400 x 400 microM). Images were read to provide staging information and to grade the signal characteristics of the individual tumors as low (dark), intermediate, or high (bright) relative to surrounding isointense fat. Patients were treated with standard megavoltage irradiation (prescribed dose, 80-85 Gray); shaped antero-posterior/postero-anterior or 4-field box techniques, plus brachytherapy, were used.


RESULTS
In 39% of patients, tumors were determined to be in a higher stage by eMRI because of proximal vaginal involvement (n = 4) or the combination of proximal vaginal involvement and parametrial extension (n = 3). Features predictive of improved local control and survival without evidence of disease included stage, hemoglobin levels > or = 11, complete response to external irradiation, and bright signal characteristics. Compared with those who had dark and/or intermediate tumors, patients who had tumors with bright signal characteristics tended to present with earlier stage disease, were less likely to have anemia, and were more likely to have complete response to external irradiation.


CONCLUSIONS
Prognostic information for clinical staging of cervical carcinoma was contributed by eMRI. The technique was more likely to suggest proximal vaginal involvement by a tumor than was examination under anesthesia. Signal characteristics of tumors may provide valuable predictive information that is supplementary to conventional discriminants of outcome that follow definitive irradiation. Such information could allow physicians to tailor treatment (e.g., by the addition of radiation sensitizers) at an earlier point in disease management.
Corn
B W
BW
Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA.
Schnall
M D
MD
Milestone
B
B
King
S
S
Hauck
W
W
Solin
L J
LJ
D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D015588:Observer Variation; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy*