10/19/11

 

LAS VEGAS – Some older adults with cancer may be dying because their oncologists withhold effective treatment solely on the basis of age, according to a founder of the field of geriatric oncology.

About 120,000 accidental deaths in the United States each year are caused by physicians, Dr. Lodovico Balducci told attendees of the annual Community Oncology Conference. "If I can leave you with a message today, it’s that doctors may kill people not because they treat people too much, but because they don’t treat people enough," he asserted.

As shown about 25 years ago, when oncologists feared giving the full-dose CHOP regimen to older adults with lymphoma and routinely reduced the dose by 25%, the complete response rate was 50% lower than it was in younger patients (J. Clin. Oncol. 1986;4:295-305). But when older adults get the same full dose of chemotherapy, they have similar response rates and survival too (Cancer 2003;98:2651-6).

"I am wondering whether age is not a risk factor for [poor outcome in] lymphoma in general, it’s more a risk factor for not receiving proper treatment," reflected Dr. Balducci, a professor of oncologic sciences at the University of South Florida, Tampa, and leader of the senior adult oncology program at the H. Lee Moffitt Cancer Center and Research Institute in that city.

"Age should not – and I underline, should not – be a factor by itself that should discourage proper treatment of cancer patients," he stressed. "This is very important because cancer is essentially a disease of aging. It’s essentially a geriatric disease."

To be sure, treatment decisions in the senior population must take into consideration individual factors such as life expectancy and likely treatment tolerance. And here, clinical assessment provides the most information.

Oncologists should assess patients’ activities of daily living (ADL), such as their ability to eat and bathe. "If you are dependent in one or more of these activities, you are definitely not a good candidate for ... any adjuvant treatment," Dr. Balducci said.

"The instrumental activities of daily living (IADL) are probably more important," he continued. They include, for example, the ability to make telephone calls, to shop, and to take medications. "If you are dependent in any one of these activities ... your death rate increases by 50%; your risk of chemotherapy toxicity increases by 100%."

Importantly, though, if a patient has been able to compensate for a disability – for example, if he or she can’t walk but has learned to use a wheelchair to get around effectively – then the patient is not considered to be dependent for that activity.

Comorbidities must also be ascertained because of their potential impact on overall prognosis, treatment toxicity, drug interactions, and even cancer growth.

Oncologists should also look for features of so-called geriatric syndromes, such as spontaneous fractures, falls, or delirium precipitated by minor infections. "These generally are all signs that indicate that the patient has not only low life expectancy, but also a poor tolerance of treatment," he commented.

The best validated measure of life expectancy in the older population in general, according to Dr. Balducci, is a prognostic index that incorporates chronological age, comorbidities, and functional measures (JAMA 2006;295:801-8). This index permits the identification, for example, of 80-year-olds who have a lower 4-year mortality risk than do some 60-year-olds.

When it comes to chemotherapy, two studies that were reported last year at the annual meeting of the American Society of Clinical Oncology showed that some of the aforementioned factors can help predict the likelihood of serious adverse effects and developed risk-stratification systems. "These studies are the first clear demonstration that the geriatric assessment is important to establish what is the risk of toxicity in older patients with cancer," Dr. Balducci commented.

Frailty is also a key consideration. The term now has a very specific meaning in geriatrics: It refers to patients who are independent but become dependent after experiencing a stressor such as surgery to resect their cancer. "At that point, you start [down] a slippery slope," he commented. Thus, "the concept of frailty helps us identify people at risk."

On average, older adults are more likely than younger ones to experience a variety of chemotherapy adverse effects, including myelosuppression, mucositis, peripheral neurotoxicity, and cardiotoxicity. "We must remember that age is also a risk factor for long-term complications of chemotherapy toxicity," such as myelodysplasia and acute myelogenous leukemia from anthracyclines, Dr. Balducci added.

But at the same time, seniors often derive similar benefit as do their younger counterparts from interventions such as the use of growth factors to prevent chemotherapy-induced myelotoxicity.

Oncologists can refer to NCCN (National Comprehensive Cancer Network) guidelines to help tailor chemotherapy in patients aged 65 years or older. The guidelines recommend, for example, that the first dose be adjusted for renal function and that prophylactic filgrastim or pegfilgrastim be given to patients who are receiving moderately toxic regimens.

"Some form of geriatric assessment should be done in all patients aged 70 and older to estimate life expectancy and risk of chemotherapy toxicity," Dr. Balducci further noted. "And of course, when you can, you should use safer agents."

Older patients today are likely to be taking multiple medications for other conditions, which can be problematic when it comes to their chemotherapy, especially given the increasing use of oral agents.

Here, oncologists can refer to the STOPP (Screening Tool of Older Persons’ Prescriptions) and START (Screening Tool to Alert Doctors to Right Treatment) criteria, which enable identification, for instance, of unnecessary or redundant medications a patient may be taking (Int. J. Clin. Pharmacol. Ther. 2008;46:72-83). "These criteria are very helpful to manage the polypharmacy," he said.

Community Oncology and Caring for the Ages are owned by Elsevier. Dr. Balducci reported receiving honoraria from Amgen, Cephalon, Sanofi-Aventis, and Novartis.

Susan London is a freelance writer based in Seattle.