Skeletal muscle radiodensity is prognostic for survival in patients with advanced non-small cell lung cancer.
Recent research indicates that severe muscular depletion (sarcopenia) is frequent in cancer patients and linked to cachexia and poor survival. Our aim was to investigate if measures of skeletal muscle hold prognostic information in advanced non-small cell lung cancer (NSCLC).



We included NSCLC patients with disease stage IIIB/IV, performance status 0-2, enrolled in three randomised trials of first-line chemotherapy (n = 1305). Computed tomography (CT) images obtained before start of treatment were used for body composition analyses at the level of the third lumbar vertebra (L3). Skeletal muscle mass was assessed by measures of the cross sectional muscle area, from which the skeletal muscle index (SMI) was obtained. Skeletal muscle radiodensity (SMD) was measured as the mean Hounsfield unit (HU) of the measured muscle area. A high level of mean HU indicates a high SMD.



Complete data were available for 734 patients, mean age 65 years. Both skeletal muscle index (SMI) and muscle radiodensity (SMD) varied largely. Mean SMI and SMD were 47.7 cm2/m2and 37.4 HU in men (n = 420), 39.6 cm2/m2and 37.0 HU in women (n = 314). Multivariable Cox regression analyses, adjusted for established prognostic factors, showed that SMD was independently prognostic for survival (Hazard ratio (HR) 0.98, 95% CI 0.97-0.99, p = 0.001), whereas SMI was not (HR 0.99, 95% CI 0.98-1.01, p = 0.329).



Low SMD is associated with poorer survival in advanced NSCLC. Further research is warranted to establish whether muscle measures should be integrated into routine practice to improve prognostic accuracy.
Dept of Internal Medicine, Innlandet Hospital Trust, Hamar, Norway; Dept of Oncology, Oslo University Hospital, Oslo, Norway. Electronic address: b.sjoblom@hotmail.com.
Bjørg
B
Sjøblom
The Cancer Clinic, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway; European Palliative Care Research Centre, Dept of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
Bjørn H
BH
Grønberg
Norwegian Centre for Violence and Traumatic Stress Studies, Oslo, Norway; Centre for Child and Adolescent Mental Health, Eastern and Southern Norway, Oslo, Norway; Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway.
Tore
T
Wentzel-Larsen
Dept of Oncology, Division of Palliative Care Medicine, University of Alberta, Edmonton, Canada.
Vickie E
VE
Baracos
European Palliative Care Research Centre, Dept of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; Regional Centre for Excellence in Palliative Care, South Eastern Norway, Oslo University Hospital, Oslo, Norway.
Marianne J
MJ
Hjermstad
Regional Centre for Excellence in Palliative Care, South Eastern Norway, Oslo University Hospital, Oslo, Norway; Faculty of Medicine, University of Oslo, Norway.
Nina
N
Aass
Dept of Oncology, University Hospital North Norway, Tromsø, Norway; Dept of Clinical Medicine, Faculty of Medicine, University of Tromsø, Norway.
Roy M
RM
Bremnes
Dept of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway.
Øystein
Ø
Fløtten
Regional Centre for Excellence in Palliative Care, South Eastern Norway, Oslo University Hospital, Oslo, Norway; Dept of Health, Nutrition and Management, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
Asta
A
Bye
Dept of Internal Medicine, Innlandet Hospital Trust, Hamar, Norway; Faculty of Medicine, University of Oslo, Norway.
Marit
M
Jordhøy
D000368:Aged; D015992:Body Mass Index; D002100:Cachexia / Q000150:complications / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000648:ultrastructure*; D011379:Prognosis; D055948:Sarcopenia / Q000150:complications / Q000473:pathology*; D014057:Tomography, X-Ray Computed
Body composition; Non-small cell lung cancer; Prognostic factor; Radiodensity; Sarcopenia; Survival