Body composition data from routine CT imaging helps clinicians diagnose, develop treatment, and predict outcomes of metastatic non-small cell lung cancer (mNSCLC), according to a study published January 7 in Cancer Medicine.
The findings could help clinicians offer mNSCLC patients better care, wrote a team led by Adriana Coletta, PhD, of the University of Utah in Salt Lake City.
"We observed a significant positive association between subcutaneous adipose tissue area, total adipose tissue area, and survival," the group wrote.
Lung cancer with metastases is the most common cause of cancer death in the U.S., and the most common disease subtype is non-small-cell lung cancer, the team noted. New therapies have improved patient outcomes, but the five-year survival rate is still only 7%, the group explained.
Oncologists assess individuals living with mNSCLC using the Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) scale to assess patients' ability to tolerate cancer; patients with a PS of 0 to 2 are given cancer treatment, while those with a PS of three or four are referred to hospice, Coletta and colleagues wrote.
Identifying "objective clinical characteristics and/or patient-centered tools that provide insight into survival rates, to complement the physician's subjective rating of PS, may yield more accurate assessment and positively impact treatment decisions," they wrote, and recent evidence suggests that "body composition variables [measured by CT imaging] and patient-reported outcomes (PROs) [such as fatigue, physical function, and depression] are possible independent prognostic factors of overall survival in varying cancer types and stages, including metastatic lung cancer."
Coletta and colleagues conducted a study to evaluate any links between body composition, overall survival, odds of receiving treatment, and PROs in people living with mNSCLC. The study included 69 patients newly diagnosed with mNSCLC who had CT scans and completed PRO questionnaires close to the diagnosis date. The study cohort was predominantly male (52%), had a history of smoking (67%), and a tumor histology of adenocarcinoma (68%).
The group found the following regarding mortality risk related to body composition:
- Larger intermuscular adipose tissue area was associated with higher mortality risk (hazard ratio [HR], 2.03 [with 1 as reference]).
- Larger subcutaneous adipose tissue area was associated with lower mortality risk (HR, 0.42). Larger total adipose tissue area was linked with improved survival (HR, 0.59).
It also reported data on the odds of receiving treatment for lung cancer based on body composition.
| Odds of receiving treatment for lung cancer based on body composition | ||
|---|---|---|
| Body composition parameter | Tissue area (cm2) | Odds ratio (with 1 as reference) |
| Skeletal muscle area | 45.6 | 1.03 |
| Intermuscular adipose tissue area | 8.8 | 0.76 |
| Visceral adipose tissue area | 122.4 | 0.99 |
| Subcutaneous adipose tissue area | 150.9 | 1.03 |
| Total adipose tissue area | 259.1 | 1 |
"We observed a significant positive association between subcutaneous adipose tissue area, total adipose tissue area, and survival," the group wrote. "However, we also observed that individuals with greater subcutaneous adipose tissue area were more likely to receive treatment, suggesting at least in the mNSCLC setting that perhaps individuals with a phenotype suggesting higher body fat experience improved survival because they are more likely to receive treatment."
The study findings show promise for developing a "more refined method to dictate treatment decisions and prognostic information," according to the authors.
"[Our] work supports the use of data collected in routine CT scans and patient-reported outcomes to inform treatment decisions and supportive care options," they concluded.
The complete study can be found here.
