DALLAS--A new study suggests that RODEO breast MRI can accurately
determine the extent of DCIS (ductal carcinoma in situ) and identify
characteristic patterns that can differentiate DCIS from more
malignant breast cancers.
DCIS is biologically a different lesion from infiltrating cancer,
and, if accurately diagnosed, conservative treatment can produce
good results, Steven E. Harms, MD, of the University of Arkansas
Cancer Research Center, Little Rock, said at the American College
of Radiology's National Conference on Breast Cancer.
However, both conventional MRI and mammography have proved inadequate
at predicting the extent of DCIS and distinguishing DCIS from
infiltrating cancer, leading to a tendency to overtreat the disease.
To provide better detection of DCIS and other breast lesions,
Dr. Harms, who was then at Baylor University Medical Center, Dallas,
developed a high-contrast, high-resolution three-dimensional MRI
technique called RODEO (rotating delivery of excitation
off-resonance). [For a report of RODEO in lobular breast
carcinomas, see Oncology News International, July, 1996,"RODEO
Breast MRI Promising in Lobular Cancer Diagnosis".]
The study presented at the symposium involved 22 breast cancers
diagnosed at pathology as pure DCIS (five cases), DCIS with microinvasion
(six cases), or infiltrating ductal carcinomas with extensive
intraductal component (EIC) (11 cases).
The study looked at the new technique's ability to determine both
disease morphology (infiltrating carcinoma or DCIS) and extent.