DUARTE, Calif., August 2, 2011 — The amount of chemotherapy patients can tolerate before toxic side effects impact treatment varies, but older patients are more vulnerable to toxicity. A new system that identifies age-related risk factors could allow for better, targeted treatments. Arti Hurria, M.D., associate professor in City of Hope’s Department of Medical Oncology & Therapeutics Research, is the lead author of a prospective multicenter study investigating a new system to predict chemotherapy toxicity specifically in older patients, available as an early release article prior to print publication in the Journal of Clinical Oncology.
“Cancer is still primarily a disease of age, and with our graying population there is a growing, critical need for better age-appropriate assessments for chemotherapy and novel personalized treatments,” said Hurria, who also serves as director of City of Hope’s Cancer and Aging Research Program. “This data will provide the basis for future intervention studies aimed at improving chemotherapy treatment options for older patients that maintain their function and health.”
The American Cancer Society estimated that 1,529,560 new cancers were diagnosed in 2010, and people over 65 years of age accounted for 60 percent of those cases. Population studies estimate there will be more than 70 million seniors living in the U.S. by the year 2030. Despite these figures, the paper cites that there are tools to evaluate chemotherapy success by age, but nothing to characterize risk of toxicity in older adults.
“Available data suggest that older adults derive similar benefits from chemotherapy as younger adults, but older patients are less likely to be offered chemotherapy because of concerns regarding their ability to tolerate the treatment,” said Hurria. “The aim of our study was to develop a predictive model for severe and life-threatening toxicity that could help physicians and older patients in discussing and deciding treatment options.”
The study, across seven institutions, enrolled 500 men and women between the ages of 65 to 91 years old with stage I-IV cancers. Of those patients, 29 percent were diagnosed with lung cancer, 27 percent with gastrointestinal cancer, 17 percent with gynecologic cancer, 11 percent with breast cancer, 10 percent with genitourinary, and 6 percent with cancer in other sites. Prior to chemotherapy, patients were assessed on metrics including sociodemographics, tumor and treatment variables, lab tests and standardized geriatric assessment variables, which are used in health care but not regularly used in cancer treatment. Patients were followed through their chemotherapy courses and researchers captured severe (grade 3), life-threatening or disabling (grade 4) side effects, or death (grade 5) from treatment as defined by the National Cancer Institute.
“We found the system we developed that incorporated geriatric assessment variables demonstrated a greater ability to discriminate risk of chemotherapy toxicity in older patients than the standard Karnofsky Performance Scale, which is used to assess patient response to treatment but does not adjust for age factors,” said Hurria. “In fact, the geriatric assessment variables alone independently predicted the risk of toxicity.”
Geriatric assessment variables take into account age-specific measures such as movement ability, age-related health conditions, cognitive function, psychological state, nutrition and the level of social activity or support. Researchers chose to study a broad range of cancers to determine if there were common factors across the geriatric populations, but say that different tumor types and treatment regimens could require assessment of additional or different risk factors.
The centers involved in the study include: University of Rochester Medical Center, Rochester, N.Y.; Case Western Reserve University, Cleveland; Wake Forest University, Winston Salem, N.C.; Yale University of Medicine, New Haven, Conn.; Memorial Sloan-Kettering Cancer Center, New York; Syracuse VA Medical Center, Syracuse, N.Y.; and Weill Medical College of Cornell University, New York. The research group plans to continue their investigations and refine their system model among patients with specific tumor types who are receiving specific treatment regimens.