By literally freezing prostate cancer cells to death, radiologists
can effectively treat prostate cancer in some patients while reducing
complication rates, preliminary results of a study show. The new
procedure, trans- rectal ultrasound-guided cryoablation, also
costs less than traditional prostate cancer treatments, the study
Of the 310 men treated with the technique so far, 90% have had
negative biopsies, said Dr. Duke Bahn, chair of the Department
of Radiology at Crittenton Hospital in Rochester, Michigan. Follow-up
of these patients ranged from 3 months to 2 years, Dr. Bahn told
the American Roentgen Ray Society at its annual meeting in Washington,
Patients with cancer confined to the prostate gland or those whose
cancer has spread near the gland are candidates for the freezing
procedure, said Dr. Bahn. Probes are inserted through small skin
punctures into the prostate gland. Liquid nitrogen is circulated
through the probes and the entire prostate is frozen. When the
prostate thaws, the cells rupture and die, he said. "The
freezing process is carefully monitored by high resolution ultrasound
to avoid injuries to adjacent organs," said Dr. Bahn. Patients
usually are only in the hospital overnight, and they can return
to their normal routine in about 2 weeks.
The cost of cryoablation is about one-third to one-half that of
surgery or radiation therapy, Dr. Bahn noted. Complication rates
appear to be much lower than rates associated with surgery. For
example, incontinence occurs in at least 30% of patients who undergo
surgery. "Our incontinence rate is only 1%," said Dr.
The cryoablation procedure can be repeated if it fails, said Dr.
Bahn. Patients also can choose to undergo radiation therapy or
surgery if cryoablation proves ineffective, he added.
"We are very optimistic about this procedure," said
Dr. Bahn. However, he cautioned, long-term clinical trials need
to be done to determine whether this treatment increases overall
survival. Transrectal ultrasound-guided cryoablation is available
in about 100 institutions across the United States.