Management of non-small-cell lung cancer in the older adult

Abstract

The treatment of older adults with non-small cell lung cancer (NSCLC) poses special challenges for the clinician. Older adults are more likely to have decreased functional reserve which might limit their ability to undergo surgery or receive chemotherapy. Additionally, age is associated with increased number of co-morbid medical conditions that could be exacerbated by treatment and could predispose to poor outcome. It is unclear how these propensities affect the efficacy and safety of therapy in older patients with NSCLC, as the elderly are an understudied population and there are limited data in older adults in most trials evaluating therapy in lung cancer. As the number of trials of older adults increases, however, it is becoming more evident that age alone cannot be used as a surrogate for poor outcome. Various studies have shown that older adults are able to benefit from surgery or chemotherapy when correct patient selection is used. Most chemotherapeutic regimens have similar efficacy in older and younger patients, and while some toxicity rates are higher in older patients, with appropriate prophylaxis and supportive care older adults are generally able to tolerate most chemotherapy regimens, even in combinations. Proper selection of candidates for aggressive therapy is important, and identification of issues that might limit ability to complete treatment or benefit from treatment is essential, and can be accomplished through the use of a comprehensive geriatric assessment. This article serves as a review of the available evidence in the evaluation, treatment, and support of the older adult with cancer.

Introduction

Lung cancer remains the most common cause of cancer death in much of the developed world. Worldwide in 2008, over 1.6 million cases of lung cancer were diagnosed and 1.4 million people died of lung cancer, representing 18.2% of all cancer deaths [1]. The median age at diagnosis of lung cancer in the US is 71 years, with 68% of individuals diagnosed at 65 years of age or higher, 31% at age 75 or higher, and 8% at age 85 or higher [2]. As such, lung cancer can be considered a disease of older adults. In addition, the incidence and mortality of lung cancer among older adults is expected to increase with the aging of the population in developing countries in the coming decades [3].

However, older adults with cancer remain understudied as compared to younger adults [4], [5], [6], [7], [8], [9]. For example, people with cancer age 70 or older made up only 20% of subjects enrolled in US Food and Drug Administration registration trials from 1995 to 1999, though they made up fully 46% of the US cancer population in that period [5]. The corresponding lack of data in older patients with lung cancer results in poorer understanding of the risks and benefits associated with cancer treatment. Despite this lack of evidenced-based research, however, older age is a primary determinant of whether patients receive guideline-specific treatment for lung cancer in clinical practice [10], [11], [12], [13], [14], [15].

Over the last decade, a great deal more has been learned about the treatment of non-small cell lung cancer (NSCLC) in older adults. In general, and against the expectations of some, it appears that older adults may be as likely to tolerate and benefit from most guideline-specific treatments for NSCLC as younger adults. In one notable example, while combination chemotherapy had been assumed to be overly toxic in older adults with advanced NSCLC, a recently presented study showed that combination therapy resulted in better efficacy than single-agent therapy even in older adults, with treatment tolerance at acceptable levels [16]. This article serves as a review of what is known in the treatment of NSCLC in the elderly in this rapidly evolving field, and will likewise provide general guidelines for assessing older adults in an attempt to determine an individual's likelihood of benefiting from cancer therapy.