A multi-institutional study demonstrated that prostate cancer
patients with aggressive tumors benefited from higher-than-standard
doses of radiation. In the trial, 79% of 102 patients receiving
radiation therapy for cancer confined to the prostate were cancer
free at 5 years. In contrast, more than half of patients who undergo
radical prostatectomy experience a recurrence at 5 years. Dr.
John B. Fiveash, formerly of the University of Michigan and now at
the University of Alabama Birmingham Medical Center led the study,
which was conducted at the University of Michigan in Ann Arbor, Fox
Chase Cancer Center in Philadelphia, and the University of California
in San Francisco.
Three-Dimensional Conformal Radiotherapy
All evaluable patients had Gleason scores between 8 and 10, said Dr.
Fiveash. Under the microscope, these tumors appear more aggressive,
and account for a higher percentage of prostate cancer deaths.
Patients in the study received a range of radiation doses from
conventional (< 70 Gy) to 80 Gy, said Dr. Fiveash. The
higher the dose, the better the patient did. Conventional doses
for prostate cancer are between 66 Gy and 70 Gy, but higher doses of
radiation can be delivered using three-dimensional conformal
radiotherapy. The technique was used for all patients in the study,
which was reported in a recent issue of the International Journal
of Radiation Oncology, Biology and Physics.
Three-dimensional conformal radiotherapy requires technical expertise
and appropriate treatment planning, Dr. Fiveash noted. If we
are to make headway in treating this disease, we must invest in
training and equipment so this technique is available in community
hospitals as well as major medical centers, he added.