[Impact of cancer muscle mass loss on anticancer treatment toxicities]

The prevalence of CT-defined low skeletal muscle mass in patients with metastatic cancer: a cross-sectional multicenter French study (the SCAN study)

Background

Cachexia, characterized by involuntary muscle mass loss, negatively impacts survival outcomes, treatment tolerability, and functionality in cancer patients. However, there is a limited appreciation of the true prevalence of low muscle mass due to inconsistent diagnostic methods and limited oncologist awareness.

Methods

Twenty-nine French healthcare establishments participated in this cross-sectional study, recruiting patients with those metastatic cancers most frequently encountered in routine practice (colon, breast, kidney, lung, prostate). The primary outcome was low skeletal muscle mass prevalence, as diagnosed by estimating the skeletal mass index (SMI) in the middle of the third-lumbar vertebrae (L3) level via computed tomography (CT). Other objectives included an evaluation of nutritional management, physical activity, and toxicities related to ongoing treatment.

Results

Seven hundred sixty-six patients (49.9% males) were enrolled with a mean age of 65.0 years. Low muscle mass prevalence was 69.1%. Only one-third of patients with low skeletal muscle mass were receiving nutritional counselling and only 28.4% were under nutritional management (oral supplements, enteral or parenteral nutrition). Physicians highly underdiagnosed those patients identified with low skeletal muscle mass, as defined by the primary objective, by 74.3% and 44.9% in obese and non-obese patients, respectively. Multivariate analyses revealed a lower risk of low skeletal muscle mass for females (OR: 0.22, P < 0.01) and those without brain metastasis (OR: 0.34, P < 0.01). Low skeletal muscle mass patients were more likely to have delayed treatment administration due to toxicity (11.9% versus 6.8%, P = 0.04).

Conclusions

There is a critical need to raise awareness of low skeletal muscle mass diagnosis among oncologists, and for improvements in nutritional management and physical therapies of cancer patients to curb potential cachexia. This calls for cross-disciplinary collaborations among oncologists, nutritionists, physiotherapists, and radiologists.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00520-021-06603-0.

Spinal cord hypermetabolism extends to skeletal muscle in amyotrophic lateral sclerosis: a computational approach to [18F]-fluorodeoxyglucose PET/CT images

PURPOSE

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease leading to neuromuscular palsy and death. We propose a computational approach to [18F]-fluorodeoxyglucose (FDG) PET/CT images to analyze the structure and metabolic pattern of skeletal muscle in ALS and its relationship with disease aggressiveness.

MATERIALS AND METHODS

A computational 3D method was used to extract whole psoas muscle's volumes and average attenuation coefficient (AAC) from CT images obtained by FDG PET/CT performed in 62 ALS patients and healthy controls. Psoas average standardized uptake value (normalized on the liver, N-SUV) and its distribution heterogeneity (defined as N-SUV variation coefficient, VC-SUV) were also extracted. Spinal cord and brain motor cortex FDG uptake were also estimated.

RESULTS

As previously described, FDG uptake was significantly higher in the spinal cord and lower in the brain motor cortex, in ALS compared to controls. While psoas AAC was similar in patients and controls, in ALS a significant reduction in psoas volume (3.6 ± 1.02 vs 4.12 ± 1.33 mL/kg; p < 0.01) and increase in psoas N-SUV (0.45 ± 0.19 vs 0.29 ± 0.09; p < 0.001) were observed. Higher heterogeneity of psoas FDG uptake was also documented in ALS (VC-SUV 8 ± 4%, vs 5 ± 2%, respectively, p < 0.001) and significantly predicted overall survival at Kaplan-Meier analysis. VC-SUV prognostic power was confirmed by univariate analysis, while the multivariate Cox regression model identified the spinal cord metabolic activation as the only independent prognostic biomarker.

CONCLUSION

The present data suggest the existence of a common mechanism contributing to disease progression through the metabolic impairment of both second motor neuron and its effector.