Improving functional capacity in surgical lung cancer patients

Abstract

Lung cancer is the most common cancer and leading cause of cancer death in Hong Kong. Surgery remains the standard of care for early-stage disease. While minimally invasive techniques have improved survival, lung cancer patients continue to experience functional capacity deterioration post-surgery. Functional capacity is an important clinical outcome and predictive of patient-centered outcomes, including quality of life and mortality. Poor functional capacity recovery can lead to persistent functional limitations throughout cancer survivorship. There is a dearth of published guidelines or recommendations regarding rehabilitation in surgical lung cancer patients, and a lack of consensus exists concerning the optimal timing and setting for rehabilitation interventions. The thesis aimed to 1) synthesize existing evidence describing the trajectories and predictors of functional deterioration in surgical lung cancer patients; 2) investigate the effects of rehabilitation either before or after lung cancer surgery on postoperative clinical outcomes; 3) evaluate the feasibility of a perioperative exercise program in surgical lung cancer patients; 4) explore the feasibility and preliminary effects of preoperative rehabilitation (prehabilitation) and health education on functional capacity, health-related quality-of-life, physical activity, and postoperative clinical outcomes in surgical lung cancer patients. My systematic review found that most lung cancer patients had a significant decline in functional capacity in the short term. In the medium term, though the decline became insignificant, the functional capacity did not return to the preoperative level. The review also identified modifiable risk factors (i.e., preoperative lung function, quadriceps force, cardiac function) related to the decline. Rehabilitation can potentially improve modifiable risk factors and prevent functional capacity deterioration. The meta-analysis study demonstrated that prehabilitation is effective in reducing postoperative pulmonary complications and length of hospital stay associated with lung cancer surgery. Therefore, interventions with a prehabilitation component can potentially improve functional capacity in surgical lung cancer patients. A perioperative exercise program (2 weeks preoperative and 12 weeks postoperative) was designed and implemented in 11 surgical lung cancer patients. This single-group feasibility study found that the 2-week prehabilitation program was safe and feasible, while the postoperative program was not feasible due to the substantial postoperative dropout.

The 2-week prehabilitation program was modified based on participant feedback. A randomized controlled trial was carried out to evaluate the feasibility and potential effects of prehabilitation and health education on postoperative functional capacity. Twenty-two participants were recruited and included in the statistical analyses. Attendance at prehabilitation sessions and adherence to self-practice were satisfactory, with 100% of participants attending 75% of scheduled sessions and 72.2% practicing home-based exercise for 90 min per week. Attendance at health education talks was 81.1%. The improvement in functional capacity measured by 6-minute walk distance was higher in the health education group at 3 months post-surgery from baseline (41.86 m, 95% CI, 13.56 to 97.28), while functional capacity in the prehabilitation group returned to baseline level (0.67 m, 95% CI, -65.10 to 66.43). Prehabilitation and health education programs appear to be feasible and acceptable among surgical lung cancer patients. To confirm the intervention effect, a fully powered trial is warranted in the future.