Lung Cancer Book—Prehabilitation Chapter

Case Study

A 63-year-old woman with a 30-pack-year history of smoking presented with mid-back pain and was found to have 4 cm right upper lobe mass. She was diagnosed with T3N0 nonsmall cell lung carcinoma by CT-guided biopsy. She was offered chemoradiotherapy with curative intent. At her multidisciplinary evaluation, she complained of fatigue. CBC revealed hematocrit of 28, MCV of 71, and iron saturation of 3%. She was referred for prehabilitation.

On functional history, she could walk one flight of stairs without shortness of breath at physiatry evaluation. She was not exercising, but was willing to start with a walking program. She was counseled on smoking cessation and was able to wean off cigarettes. The dietician recommended iron supplementation and increased protein intake with examples of iron and protein-rich foods.

She started with a walk of half her 400 m driveway five times a week for the first week, and then was able to walk her whole driveway the second week, even during chemotherapy. She had to rest the third week when she started radiation. She went back to walking half the driveway the fourth week and the full driveway the fifth week. On the eighth week, she was able to walk down the street. By the twelfth week, she could walk one mile. After she finished radiation, she celebrated by walking 2 miles, five times per week. In the beginning, she hated the exercise. Then, her husband started joining her. They both felt better because he felt like that was something he could do to help and she slept better on the days that she walked. She is now in remission and enjoys walking up to 4 miles daily.

Introduction

A diagnosis of lung cancer carries immediate risks to health in addition to cancer mortality, such as perioperative surgical complications and toxicities of chemotherapy and radiation. More than in any other type of cancer, overall physical and lung function factors into the decision for the type of treatment administered. Improving aerobic function in patients with lung cancer not only improves quality of life, but may improve the efficacy of cancer treatment and prolong life expectancy.

Patients treated with surgery for lung cancer experience a decrease in physical activity. Although types of recommended preoperative exercise are admittedly diverse, a Cochrane review showed that exercise interventions before lung cancer surgery may improve exercise capacity and lung function as well as reduce postoperative complications and hospital length of stay in patients with nonsmall cell lung cancer.

Common Physical Impairments in Prehabilitation

In one sample of nonsmall cell lung cancer patients, fatigue was the most common symptom and was present in 100% of the 450 subjects. Loss of appetite, shortness of breath, cough, pain, and blood in the sputum were the other common impairments. Fatigue is particularly amenable to exercise in cancer and prehabilitation may be the best time to start before treatments that have fatigue as a known potential adverse effect. Dietary consultation can be helpful for loss of appetite. Protein supplementation is of particular importance in improving outcomes in cancer. Although shortness of breath can cause patients to be fearful of aerobic exercise, exercise is a known panacea for dyspnea and smoking cessation has respiratory benefits. The potential to decrease pain and expel respiratory secretions are other benefits of prehabilitation.

Unimodal and Multimodal Prehabilitation

Prehabilitation is defined as “a process on the continuum of care that occurs between the time of diagnosis and the beginning of acute treatment, includes physical and psychological assessments that establish a baseline functional level, identifies impairments, and provides targeted interventions that improve a patient's health to reduce the incidence and severity of current and future impairments.”

Surgical prehabilitation has the most evidence, and the most common form of unimodal prehabilitation is exercise.

Unimodal prehabilitation has been used for lung resection as early as 1997. 32 patients with chronic obstructive pulmonary disease were randomized to perioperative exercise or no exercise. The exercise group had incentive spirometry and specific inspiratory muscle training starting 2 weeks before surgery and continuing for 3 months after. Those in the exercise group had better inspiratory muscle strength and lung function after surgery than those without that intervention. Another study extended the duration of preoperative rehabilitation to 4 weeks and measured the preoperative function of an intervention group compared to a control group that got only chest physiotherapy. This more intensive whole body exercise intervention resulted in improved preoperative functional capacity and decreased postoperative pulmonary complications. A third study showed that as little as 7 days of exercise may demonstrate a benefit in lung cancer patients.

In addition to the previously mentioned Cochrane review, at least eight other reviews have examined perioperative function in patients with lung cancer. Preoperative physical therapy was recommended to last 2–4 weeks and should include both aerobic and strength training components. Moderate or greater intensity was important. Supervision and individualization were recommended.

Five ^, of the reviews recommend preoperative and postoperative exercise interventions equally, while one concluded that preoperative training is more beneficial for both preoperative and postoperative outcomes. One of the five studies did note that postoperative exercise interventions require a longer training period to demonstrate efficacy. Proponents of prehabilitation suggest that not only is a shorter training period required to see benefit before surgery, but that patients are looking for an intervention to improve their outcomes during their waiting time for surgery.

Authors of two of the reviews ^, that included metaanalysis found that preoperative exercise training may shorten hospital length of stay and reduce postoperative pulmonary complications. One described improved preoperative lung function and the other cited increased 6-minute walk distance. Both improved lung and overall function may be the mechanism for reduced length of stay and fewer pulmonary complications. The 6 min-walk test is less expensive and easier to measure than lung function, but may not affect the decision to offer surgery, which typically depends heavily on lung function and imaging.

A pulmonary rehabilitation program should ideally include both aerobic and strength training components with a duration of two to 4 weeks. A 4-week graded aerobic program adding 10 minutes per week has been effective in improving the 6-minute walk test in subjects with lung cancer. The rate of perceived exertion can be used to titrate exercise prescription.

Although there are extensive data on the use of exercise in pulmonary prehabilitation, less is known about the other components recommended for successful multimodal prehabilitation. These include nutrition, smoking cessation, psychologic support, and education. Authors of one review article annotated which programs offered multimodal prehabilitation as opposed to unimodal, and this was only one out of the six studies. Exercise was the primary intervention of the unimodal studies and both aerobic and strength training were recommended.

The components of a multimodal prehabilitation program are best used together. For example, exercise is not going to be helpful if the patient does not get enough protein to increase muscle strength. Protein requirements are elevated in cancer. Oncology patients are recommended to consume between 1.2 and 2 gm/kg of protein daily. Whey protein supplements can be particularly helpful postexercise. Patients may be more amenable to dietary changes prior to starting treatments that can affect their appetite.

One pulmonary prehabilitation pilot program that included smoking cessation along with exercise and pharmacologic optimization demonstrated improved exercise capacity in subjects. A review on smoking cessation before lung cancer surgery found six other studies on this topic, but could make no conclusion on benefit. The biggest limitation is that subjects cannot be randomized to quit smoking before surgery. However, there is a plethora of evidence that smoking worsens outcomes in cancer.

Psychologic prehabilitation has been studied in breast, colon, and prostate cancer patients. Many cancer patients suffer psychological distress. Treating underlying mood disorders and cancer-associated adjustment disorders improves wound healing and pain. Examples of psychologic prehabilitation include relaxation techniques and guided imagery.

Patient education is recommended in lung cancer, but outcomes of education as part of a prehabilitation program have not been specifically reported. One documented lung cancer rehabilitation program led by nursing includes the following educational topics: admission and discharge information, physiotherapy, pain management, nutrition, adjuvant treatment, smoking cessation, and information and support services. In-person education is recommended over internet resources for a number of reasons, not the least of which is the readability level of these resources.

Education components dovetail nicely with other components of multimodal prehabilitation. Nutrition may be more relevant to those at the extremes of body mass index, but smoking cessation may be of particular importance for many lung cancer patients. Psychologic prehabilitation may be more effective in those with comorbid mood disorders. Some prehabilitation programs also include optimization of cardiopulmonary or pain medications, correction of anemia, and alcohol cessation. Funding for components other than exercise can be difficult to secure. The best strategy may be patient education as that is the least expensive and often already occurring through the nurse navigator or other team members. Integration of a nurse navigator, who performs the significant proportion of patient education, into the triage process in nonsmall cell lung cancer improves outcomes.