Nick Mulcahy

October 27, 2009

October 27, 2009 — Although the upcoming American Society for Therapeutic Radiology and Oncology (ASTRO) 51st Annual Meeting touts numerous practice-changing studies, the organization's incoming president says that the meeting will not feature any "big surprises."

Dr. Anthony Zietman (Courtesy of ASTRO)

Anthony Zietman, MD, who is professor of radiation oncology at Harvard Medical School in Boston, Massachusetts, said that the meeting's overriding feel will be one of a "consolidation" of various data that indicate "what is reasonable" for clinical practice.

The days of going our own way are over.

He also suggested that clinicians, including radiation oncologists, should have an ear cocked toward the nation's capital. "The buzzword in Washington is evidence-based medicine," said Dr. Zietman. "We have to practice according to evidence and look at evidence carefully. The days of going our own way are over," he told Medscape Oncology.

The meeting will present multiple studies that should help clinicians refine their thinking about a number of common and important clinical situations.

Perhaps most notably, ASTRO will be feature the late-breaking initial results of Radiation Therapy Oncology Group (RTOG) 94-08, a large randomized trial that evaluates whether or not short-term hormonal therapy prior to and during radiation therapy improves overall survival in locally confined good-prognosis prostate cancer.

"We wanted to know who needed short-term hormone therapy," he summarized, noting that the therapy totaled 4 months.

The 1900-patient trial has 2 outstanding credentials: it's large and has a long follow-up, Dr. Zietman added.

The median follow-up time in the trial is a little more than 8 years, which approaches the length of time needed for meaningful results in prostate cancer, he said. "Results need to be at least 10 years out to be meaningful."

The study results, even at 8 years, are important because of the widespread use of short-term hormone therapy, especially leuprolide (Lupron), explained Dr. Zietman. "This almost became the norm with urologists," he said, adding that the use of short-term hormone therapy in low-risk prostate cancer patients undergoing radiation therapy jumped from about 10% of all such patients to about 50% during the mid- to late-1990s. Eventually, the usage tailed off when financial incentives to use the therapy ended, he said.

Clinicians took the evidence too far.

Although leuprolide use in low-risk patients was partly fueled by financial considerations, it also was probably spurred on by clinicians not sticking to evidence-based medicine, Dr. Zietman said. "Clinicians took the evidence too far," he noted, referring to studies such as RTOG 86-10, in which the short-term therapy provided a number of benefits to men with locally advanced prostate cancer.

The new results provide some direction for clinicians, suggested an RTOG 86-10 study author. "The study provides strong scientific evidence that shows us when to deliver hormone therapy with radiation in patients with localized prostate cancer," said Christopher U. Jones, MD, a radiation oncologist at Radiological Associates of Sacramento in California, in a press statement.

Meeting Themes

A general concern of Dr. Zeitman's about the practice of oncology, including radiation oncology, is that "we may be overdoing it."

'What is dispensable?' has become an important question.

"'What is dispensable?' has become an important question," he told Medscape Oncology, adding that reducing adverse effects is a "theme of the meeting."

All cancer treatment comes with a "price," such as adverse effects, he added.

In keeping with the spirit of evaluating therapies with potential significant adverse effects, the meeting will feature, at the plenary session, an investigation into delivering radiation to the internal mammary lymph nodes or chain behind the breast bone — and thus close to the heart and lungs (abstract 1).

The study, which provides 10 years of follow-up, evaluated the use of internal mammary chain radiation treatment in 1330 patients with either lymph node positive breast cancer or cancers located in an internal central location of the breast area.

Both of these kinds of cancers are more likely to spread to the internal mammary lymph nodes or chain. Because it is difficult to deliver the radiation this area, it is not done at all centers, noted Dr. Zietman.

Patient convenience is also a theme of the meeting, noted Dr. Zietman.

Addressing this issue are a number of studies that compare shorter-term courses of more intensive hypofractionated radiation with longer courses of conventional radiation therapy.

For example, 1 study to be presented (abstract 172) compares a 5-week course of intensity-modulated radiation therapy with 7.5 weeks of standard radiation therapy in intermediate- and high-risk prostate cancer patients. Another study (abstract 168) of high-risk prostate cancer patients compares 4 weeks of 3-dimensional conformal radiation therapy with 8 or 9 weeks of standard therapy.

Likewise, a study of early-stage breast cancer (abstract 162) compares 3 weeks of accelerated hypofractionated whole breast irradiation with a 5- to 7-week course of standard radiation. Similar studies have been conducted in Canada and Europe, but there are "limited data" on this topic in the United States, said Dr. Zietman, adding that Americans often feel more comfortable when new approaches are evaluated on their home ground.

In keeping with the thematic concerns about adverse effects and patient convenience and comfort, a study will also be presented about preferences among cancer patients receiving radiation (abstract 186) — with regard to what they want from their radiation oncologist. The study reveals preferences about, among other things, being told the truth, hand holding, and using first names in addressing patients.

Patients don't want computer-screen doctors as the alternative.

Dr. Zietman believes that younger physicians should especially be interested in the study results. "Many younger doctors are not evening making eye contact with patients today," he said, explaining that the newer generation of clinicians are overly oriented toward technology. "I think it's safe to say that the days of paternalism are over, but patients don't want computer-screen doctors as the alternative," he opined.


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