Highlights from ASTRO 2014

By: Rahul Tendulkar, MD

Greetings from the ASTRO meeting in San Francisco! On Monday, September 15 there were a number of interesting presentations and findings.

Discoveries in Lung Cancer
Kevin Stephans, MD, a radiation oncologist at Taussig Cancer Institute, presented data from Cleveland Clinic regarding stereotactic body radiation therapy in the treatment of medically inoperable early stage lung cancer. Dr. Stephans and his colleagues found that a dose of 60 Gray in three fractions was associated with improved local control compared to other fractionation regimens. This was the most compelling evidence to date that one SBRT dosing schedule may be superior to another, and it highlights the need for a randomized trial to establish the optimal dose.

Mastectomy and Breast Reconstruction Data
Neil Woody, MD, from Cleveland Clinic’s Taussig Cancer Institute, presented one of the largest series in the literature regarding complications following a mastectomy and implant based reconstruction. His team found that certain patient factors such as BMI, hypertension and smoking can increase toxicity rates, as can treatment-related factors such as radiation therapy to the implant. As mastectomy rates are increasing nationally due to patient selection, it is important that patients are counseled about their potential risks prior to surgical decision-making. Many women might alternatively be candidates for breast conservation, which has been shown to be associated with equivalent survival rates as mastectomy in several older randomized trials.

Findings in Prostate Cancer
At the plenary session, Jeff Michalski, MD, from Washington University presented the results of RTOG 0126, which was a phase 3 randomized trial comparing low-dose versus high-dose radiation therapy for prostate cancer using modern conformal techniques. There have been four previously published randomized trials comparing radiation dose, and this was the largest and most modern study to date. The investigators found that higher dose radiation therapy improved biochemical cure rates in the treatment of prostate cancer, which is consistent with the previous trials. There was no difference in overall survival however, likely due to effective salvage androgen deprivation therapy for men who are not cured by radiation upfront. The high-dose radiation was also associated with an acceptably small but statistically significant increase in rectal and bladder toxicities. This study underscores the importance of balancing higher cure rates while attempting to minimize side effects.