Precision oncology demands fluency in drug toxicity by radiologists

A team of Harvard radiologists is advising fellow rads to bone up on imaging-evident drug toxicity so as to shed their reputation as providers of a standalone service and, more to the point, cement their role as central members of the cancer team in this era of precision oncology.

Publishing their guidance in the July edition of the American Journal of Roentgenology, Stephanie Howard, MD, and colleagues at Dana Farber Cancer Institute and Brigham & Women’s Hospital present a primer on toxicity along with an exhortation to dive into sometimes-unfamiliar waters.

“As surgical options become increasingly considered in patients with advanced disease, radiologists must familiarize themselves with appearances of drug toxicity in organs that may undergo resection,” they write, “so that they can alert their oncology colleagues of changes concerning for low-grade toxicity that may first be detected incidentally on restaging scans.”

Howard and team note that that cancer imaging is expected to grow markedly along with cancer survivorship over the next few years, with one major SEER-based study projecting 18.1 million cancer survivors in 2020—up from 13.8 million in 2010.

In the face of this increase, and with precision oncology coming into its own, oncologists are increasingly using combinations of cytotoxic agents, molecular targeted therapies and immune checkpoint inhibitors. In this landscape, it’s increasingly important that radiologists “not only identify toxicity early, but also fully understand the implications of the findings that they report,” the authors write.

They offer examples of this perspective as applied to practice, including a scenario in which imaging-evident toxicity doesn’t necessarily call for drug cessation.

“Low levels of toxicity noted with molecular targeted agents and immune checkpoint inhibitors have increasingly been shown to correlate with drug efficacy,” they point out, “and less-severe toxicity may be deemed acceptable and, at times, even welcomed by the oncologic team.”

Meanwhile, as metastasectomies become more common in the control of advanced disease, cancer teams increasingly prioritize reducing harm to organs that may be subject to surgical intervention later on.

Then too, clinical trials are now looking at ways to safely and efficaciously combine drugs from various classes. This presents a situation that “often amplifies toxicity, mandating that radiologists not simply memorize the side effects a drug may cause but also consider the alterations of toxicity profiles with combined regimens and anticipate some of the long-term implications these side effects may have.”

Howard and team devote the bulk of their article to exploring and explaining some of the most pressing particulars of toxicity. Throughout, they emphasize the need for radiologists to embrace this aspect of cancer care and see it from the oncologist’s eye view.

“To effectively communicate with their oncology colleagues, radiologists must understand toxicity grading and must be familiar with situations in which toxicity may be more or less likely to be tolerated,” the authors write.  

“Radiologists must understand the language and multifaceted nuances of toxicity to contribute to optimized care of cancer patients,” they conclude, “and remain relevant, effective members of the oncologic team.”