Italian Study Correlates Acute and Late Toxicity in 3-D Conformal External Beam Radiation Therapy for Prostate Cancer

Acute toxicity is more prevalent in men age 65 or younger who receive 3-D conformal external beam radiation therapy for prostate cancer, according to a recent study reported in the Feb. 2, 2010, International Journal of Radiation Oncology Biology and Physics.

Barbara A. Jereczek-Fossa, M.D., Ph.D., and colleagues assessed the effects of the patient, tumor and treatment on injuries following radiation therapy for 973 patients with prostate cancer. A total of 542 participants received definitive therapy and 431 underwent postprostatectomy radiation treatments.

The 3-D conformal radiation therapy included a six-field technique and two-dynamic arc therapy, with toxicity based on the criteria defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment.

A multivariate analysis showed that age and use of the 3-D, six-field technique correlated significantly with greater acute rectal toxicity, with a dose greater than 70 Gy and longer duration related to greater acute urinary toxicity. The severity of an acute toxicity, Grade 2 or greater, also predicted the severity of late toxicity in both rectal and urinary events.

"The results of our study have shown that the risk of acute reactions depends on both patient-related (age) and treatment-related (dose, technique) factors," the researchers concluded. "Acute toxicity was an independent significant predictor of late toxicity. These findings might help predict and prevent late radiotherapy-induced complications."