Impact of low skeletal muscle mass on non-lung cancer mortality after stereotactic body radiotherapy for patients with stage I non-small cell lung cancer

The prevalence of sarcopenia amongst non-small cell lung cancer patients, assessed using computed tomography, prior to treatment in a South African setting

Background: Identification of sarcopenia in lung cancer is important to improve quality of life and treatment planning; however, clinical detection is challenging. Computed tomography (CT) may improve detection and assist with dose adjustment and prognostication.Aim: To use CT to assess the prevalence of sarcopenia amongst non-small cell lung cancer (NSCLC) patients prior to treatment.Setting: Non-small cell lung cancer patients (n = 66) attending Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) medical oncology clinic between 01 July 2017 and 01 July 2020 with staging CTs or CT chests including L3 level done at CMJAH prior to treatment.Methods: The L3 skeletal muscle index (SMI L3) was assessed based on the cross-sectional muscle area at L3 vertebral level on CT. The prevalence of sarcopenia was determined based on gender-specific cut-offs defined by the International Consensus on Cancer Cachexia.Results: The overall prevalence of sarcopenia was 69.7% (n = 46). There was a statistically significant difference in sarcopenia prevalence according to gender (males 82.2% [n = 37] compared to females 42.9% [n = 9] [p = 0.00]) and body mass index (BMI) ( 18.5 kg/m2 [91.7%, n = 11], 18.5 kg/m2 – 24.9 kg/m2 [81.3%, n = 26], 25 kg/m2 – 29.9 kg/m2 [64.3%, n = 9], ≥ 30 kg/m2 [0.0%, n =0] [p = 0.00]), only noted between the ≥ 30 kg/m2 BMI group and remainder of BMI groups on pairwise comparison. The median SMI L3 in men was 43.1 cm2/m2 (interquartile range [IQR]: 13.6 cm2/m2) whilst the median SMI L3 in women was 40.3 cm2/m2 (IQR: 11.5 cm2/m2). No statistically significant difference in sarcopenia prevalence was demonstrated according to age group, ethnicity, stage and histology.Conclusion: There was a high overall prevalence of sarcopenia, as determined by CT, amongst NSCLC patients in a South African setting. The differences based on gender and BMI indicate potential avenues for future research. 

Cancer, Phase Angle and Sarcopenia: The Role of Diet in Connection with Lung Cancer Prognosis

Lung cancer is the most common cause of cancer death and is associated with malnutrition and sarcopenia. The detection of sarcopenia and conduction of simple body composition measurements, such as the phase angle (PhA) deriving from bioelectrical impedance analysis (BIA), can help to early identify, monitor, prevent and treat malnutrition. The present review aims to clarify the relationship between PhA and sarcopenia with the pathophysiology, clinical outcomes, and therapeutic aspects of lung cancer. PhA and sarcopenia are connected to lung cancer prognosis through various mechanisms including inflammation and oxidative stress, although more research is needed to identify the critical thresholds for increased mortality risk. Moreover, emphasis is given on the role of dietary interventions (oral nutritional supplementation, and dietary counseling) to manage sarcopenia and related variables in patients with lung cancer. Oral nutritional supplements and/or those containing n - 3 polyunsaturated fatty acids may have a positive effect on physical strength measures and muscle mass if administered at the beginning of chemotherapy. Data on sole dietary counseling or multimodal interventions are less promising so far. In the future, sophisticated body composition phenotypes deriving from the described methods along with artificial intelligence techniques could be used to design personalized nutrition interventions and timely treat these patients.

Utility of Noncancerous Chest CT Features for Predicting Overall Survival and Noncancer Death in Patients With Stage I Lung Cancer Treated With Stereotactic Body Radiotherapy

Background: Noncancerous imaging markers can be readily derived from pretreatment diagnostic and radiotherapy planning chest CT examinations. Objective: To explore the ability of noncancerous features on chest CT to predict overall survival (OS) and noncancer-related death in patients with stage I lung cancer treated with stereotactic body radiation therapy (SBRT). Methods: This retrospective study included 282 patients (168 female, 114 male; median age, 75 years) with stage I lung cancer treated with SBRT between January 2009 and June 2017. Pretreatment chest CT was used to quantify coronary artery calcium (CAC) score, pulmonary artery (PA)-to-aorta ratio, emphysema, and body composition in terms of the cross-sectional area and attenuation of skeletal muscle and subcutaneous adipose tissue at the T5, T8, and T10 vertebral levels. Associations of clinical and imaging features with OS were quantified using a multivariable Cox proportional hazards (PH) model. Penalized multivariable Cox PH models to predict OS were constructed using clinical features only and using both clinical and imaging features. Models' discriminatory ability was assessed by constructing time-varying ROC curves and computing AUC at prespecified times. Results: After a median OS of 60.8 months (95% CI 55.8-68.9), 148 (52.5%) patients died, including 83 (56.1%) with noncancer deaths. Higher CAC score (11-399: hazard ratio [HR] 1.83 [95% CI 1.15-2.91], P=.01; ≥400: HR 1.63 [95% CI 1.01-2.63], P=.04), higher PA-to-aorta ratio (HR 1.33 [95% CI 1.16-1.52], P<.001, per 0.1-unit increase), and lower thoracic skeletal muscle index (HR 0.88 [95% CI 0.79-0.98], P=.02, per 10 cm²/m² increase) were independently associated with shorter OS. Discriminatory ability for 5-year OS was greater for the model including clinical and imaging features than for the model including clinical features only (AUC, 0.75 [95% CI 0.68-0.83] versus 0.61 [95% CI 0.53-0.70], p < .01). The model's most important clinical or imaging feature based on mean standardized regression coefficients was the PA-to-aorta ratio. Conclusions: In patients undergoing SBRT for stage I lung cancer, higher CAC score, higher PA-to-aorta ratio, and lower thoracic skeletal muscle index independently predicted worse OS. Clinical Impact: Noncancerous imaging features on chest CT performed before SBRT improve survival prediction compared with clinical features alone.

Older cancer patients receiving radiotherapy: a systematic review for the role of sarcopenia in treatment outcomes

BACKGROUND

Previous studies have evaluated the prognostic effects of sarcopenia in cancer patients receiving various treatments, including chemotherapy and surgery, but few studies have focused on radiotherapy (RT).

AIMS

We aimed to investigate the prevalence of sarcopenia and the relationship between sarcopenia and outcomes in older cancer patients who underwent RT without chemotherapy.

METHODS

A systematic review of the literature was conducted in Pubmed/Medline and Cochrane databases in September 2021. We used the search terms and medical subject heading terms "sarcopenia," "low muscle mass (LMM)," "low muscle strength," "LMM and low muscle strength," "LMM and low muscle strength and low physical performance," and "RT." Outcomes were overall survival (OS), progression-free survival, non-cancer death, cancer death, disease-specific survival, local failure-free survival, distant failure-free survival, and RT-related toxicities.

RESULTS

Among 460 studies, 8 studies were eligible for inclusion. The prevalence of sarcopenia was between 42.8% and 72%. Sarcopenia was not associated with OS or OS at 3 years in seven studies in which it was defined as the presence of LMM, while it was related in one study, in which it was defined as the concomitant presence of LMM and muscle strength/function.

DISCUSSION

There was heterogeneity between the studies because there was diversity in their inclusion criteria, definition and assessment methods used for detection of sarcopenia, considered cutoffs for low muscle mass and strength, cross-sectional locations on imaging to assess muscle mass and included covariates. The discrepancy in the results of the studies may also result from the variations in diagnoses, sample sizes, and treatment modalities. The low number of included studies and a small number of patients in each study limited generalizability.

CONCLUSIONS

Sarcopenia may be a prognostic factor, especially in OS when low muscle strength/function is integrated into its definition. We suggest that clinicians focus on muscle strength/function while considering sarcopenia and its association with cancer and RT-related outcomes.

Sarcopenia Is an Independent Risk Factor for Proximal Junctional Disease Following Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Sarcopenia is a risk factor for medical complications following spine surgery. However, the role of sarcopenia as a risk factor for proximal junctional disease (PJD) remains undefined. This study evaluates whether sarcopenia is an independent predictor of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) following adult spinal deformity (ASD) surgery.

METHODS

ASD patients who underwent thoracic spine to pelvis fusion with 2-year clinical and radiographic follow-up were reviewed for development of PJK and PJD. Average psoas cross-sectional area on preoperative axial computed tomography or magnetic resonance imaging at L4 was recorded. Previously described PJD risk factors were assessed for each patient, and multivariate linear regression was performed to identify independent risk factors for PJK and PJF. Disease-specific thresholds were calculated for sarcopenia based on psoas cross-sectional area.

RESULTS

Of 32 patients, PJK and PJF occurred in 20 (62.5%) and 12 (37.5%), respectively. Multivariate analysis demonstrated psoas cross-sectional area to be the most powerful independent predictor of PJK (P = .02) and PJF (P = .009). Setting ASD disease-specific psoas cross-sectional area thresholds of <12 cm² in men and <8 cm² in women resulted in a PJF rate of 69.2% for patients below these thresholds, relative to 15.8% for those above the thresholds.

CONCLUSIONS

Sarcopenia is an independent, modifiable predictor of PJK and PJF, and is easily assessed on standard preoperative computed tomography or magnetic resonance imaging. Surgeons should include sarcopenia in preoperative risk assessment and consider added measures to avoid PJF in sarcopenic patients.

Impact of pre-treatment C-reactive protein level and skeletal muscle mass on outcomes after stereotactic body radiotherapy for T1N0M0 non-small cell lung cancer: a supplementary analysis of the Japan Clinical Oncology Group study JCOG0403

This study aimed to evaluate the impact of pretreatment C-reactive protein (CRP) and skeletal muscle mass (SMM) on outcomes after stereotactic body radiotherapy (SBRT) for T1N0M0 non-small cell lung cancer (NSCLC) as a supplementary analysis of JCOG0403. Patients were divided into high and low CRP groups with a threshold value of 0.3 mg/dL. The paraspinous musculature area at the level of the 12th thoracic vertebra was measured on simulation computed tomography (CT). When the area was lower than the sex-specific median, the patient was classified into the low SMM group. Toxicities, overall survival (OS) and cumulative incidence of cause-specific death were compared between the groups. Sixty operable and 92 inoperable patients were included. In the operable cohort, OS significantly differed between the CRP groups (log-rank test p = 0.009; 58.8% and 83.6% at three years for high and low CRP, respectively). This difference in OS was mainly attributed to the difference in lung cancer deaths (Gray's test p = 0.070; 29.4% and 7.1% at three years, respectively). No impact of SMM on OS was observed. The incidence of Grade 3-4 toxicities tended to be higher in the low SMM group (16.7% vs 0%, Fisher's exact test p = 0.052). In the inoperable cohort, no significant impact on OS was observed for either CRP or SMM. The toxicity incidence was also not different between the CRP and SMM groups. The present study suggests that pretreatment CRP level may provide prognostic information in operable patients receiving SBRT for early-stage NSCLC.

Sarcopenia is associated with poor prognosis after chemoradiotherapy in patients with stage III non-small-cell lung cancer: a retrospective analysis

We intended to investigate whether muscle and adipose masses were associated with prognosis among patients with stage III non-small-cell lung cancer (NSCLC) who were undergoing chemoradiotherapy (CCRT). We retrospectively explored data of patients with stage III NSCLC who underwent definitive CCRT (≥ 60 Gy) between January 2004 and March 2018 at our hospital. We examined the relationship of overall survival (OS) with body mass index (BMI), skeletal muscle index (SMI), psoas muscle index (PMI), visceral adipose tissue index (VAI), subcutaneous adipose tissue index (SAI), and visceral-to-subcutaneous adipose tissue area ratio (VSR) using log-rank tests for the univariate analysis and Cox proportional hazard models for the multivariate analysis. Overall, 16, 32, and 12 patients had stage IIIA, IIIB, and IIIC NSCLC, respectively. The total radiotherapy dose ranged from 60 Gy/30 fractions to 66 Gy/33 fractions. In the univariate analysis, the performance status (PS), BMI, and SMI were associated with OS, whereas the PMI, VAI, SAI, and VSR were not. In the multivariate analysis, the PS and SMI were associated with OS. The hazard ratios and 95% confidence intervals were 2.91 and 1.28–6.64 for PS, and 2.36 and 1.15–4.85 for SMI, respectively. The 1, 3, and 5-year OS rates were 92.1%, 59.6%, and 51.0% in patients with high SMI, and 63.6%, 53.8%, and 17.9% in patients with low SMI, respectively. The SMI correlated with prognosis in our study population, whereas adipose mass did not. Therefore, sarcopenia should be considered while predicting the OS in such patients.

Radiotherapy before or during androgen-deprivation therapy does not blunt the exercise-induced body composition protective effects in prostate cancer patients: A secondary analysis of two randomized controlled trials

BACKGROUND

Androgen deprivation therapy (ADT) contributes to lean mass loss and adiposity increases in prostate cancer patients. Radiotherapy during ADT might act synergistically and further worsen body composition. Previous investigations have shown that resistance training is an effective method of preserving body composition during ADT, however, most have not accounted for direct or indirect effects of other therapies, such as radiotherapy. Therefore, the purpose of this study was to examine training adaptations of the tissue composition in patients receiving radiation therapy (RT) prior or during ADT.

METHODS

Analyses were performed by combining data from two previous trials for a total of 131 prostate cancer patients who underwent a combination of resistance and aerobic exercise training (N = 70, age: 68.9 ± 6.6y, RT-before: 13%, RT-during: 14%) or usual care (N = 61, age: 67.5 ± 7.9y, RT-before: 16%, RT-during: 20%) for 3 months upon ADT onset. Whole-body lean mass (LM), fat percentage and appendicular LM were determined by dual energy x-ray absorptiometry, and lower-leg muscle area and density by peripheral computed tomography at baseline (onset of ADT) and at 3 months post-intervention. Covariates included RT prior and during the intervention, demographic characteristics, physical symptoms, and chronic conditions.

RESULTS

Radiotherapy before or during the intervention did not affect body composition. Only the usual care group experienced a significant decrease in whole-body LM (-994 ± 150 g, P < 0.001) and appendicular LM (-126 ± 19 g, P < 0.001), and an increase in whole-body fat percentage (1% ± 0.1%, P < 0.001). There was no change in lower-leg muscle area or density in either group.

CONCLUSION

We suggest that radiation prior to and during ADT does not interfere with the beneficial effects of exercise training on body composition in men with prostate cancer.

Prognostic value of low skeletal muscle mass in patient treated by exclusive curative radiochemotherapy for a NSCLC

Low skeletal muscle mass is a well-known prognostic factor for patients treated for a non-small-cell lung cancer by surgery or chemotherapy. However, its impact in patients treated by exclusive radiochemotherapy has never been explored. Our study tries to evaluate the prognostic value of low skeletal muscle mass and other antropometric parameters on this population. Clinical, nutritional and anthropometric date were collected for 93 patients treated by radiochemotherapy for a NSCLC. Anthropometric parameters were measured on the PET/CT by two methods. The first method was a manual segmentation at level L3, used to define Muscle Body Area (MBA_L3), Visceral Fat Area (VFA_L3) and Subcutaneous Fat Area (SCFA_L3). The second method was an software (Anthropometer3D), allowing an automatic multislice measurement of Lean Body Mass (LBM_Anthro3D), Fat Body Mass (FBM_Anthro3D), Muscle Body Mass (MBM_Anthro3D), Visceral Fat Mass (VFM_Anthro3D), and Sub-Cutaneous Fat Mass (SCFM_Anthro3D) on the PET/CT. All anthropometrics parameters were normalised by the patient's height. The primary end point was overall survival time. Univariate and then stepwise multivariate cox analysis were performed for significant parameters. Finally, Spearman's correlation between MBA_L3 and MBM_Anthro3D was assessed. Forty-one (44%) patients had low skeletal muscle mass. The median overall survival was 18 months for low skeletal muscle mass patients versus 36 months for non-low skeletal muscle mass patients (p = 0.019). Low skeletal muscle mass (HR = 1.806, IC95% [1.09–2.98]), serums albumin level < 35 g/l (HR = 2.203 [1.19–4.09]), Buzby Index < 97.5 (HR = 2.31 [1.23–4.33]), WHO score = 0 (HR = 0.59 [0.31–0.86] and MBM_Anthro3D < 8.56 kg/m² (HR = 2.36 [1.41–3.90]) were the only significant features in univariates analysis. In the stepwise multivariate Cox analysis, only MBM_Anthro3D < 8.56 kg/m² (HR = 2.16, p = 0.003) and WHO score = 0 (HR = 0.59, p = 0.04) were significant. Finally, muscle quantified by MBA_L3 and MBM_Anthro3D were found to be highly correlated (Spearman = 0.9). Low skeletal muscle mass, assessed on the pre-treatment PET/CT is a powerful prognostic factor in patient treated by radiochemotherapy for a NSCLC. The automatic software Anthropometer3D can easily identify patients a risk that could benefit an adapted therapy.

Sarcopenia is related to poor prognosis in patients after trimodality therapy for locally advanced non-small cell lung cancer

BACKGROUND

The association between sarcopenia and prognosis in patients with locally advanced non-small cell lung cancer (NSCLC) undergoing trimodality therapy, consisting of preoperative concurrent chemoradiotherapy and surgery, has not been reported. Therefore, we aimed to investigate the association of sarcopenia and fat mass with prognosis after trimodality therapy.

METHODS

To assess sarcopenia, the psoas muscle mass was measured. Using computed tomography data, including third lumbar vertebra level images, psoas muscle mass and visceral and subcutaneous fat mass were measured. Additionally, body mass indices, and visceral/subcutaneous fat ratio, obtained by dividing the visceral fat index by the subcutaneous fat index, were calculated. We investigated the relationship between these parameters and overall survival.

RESULTS

Ninety-nine eligible patients were included. In the univariate analysis, age, clinical stage, tumor location, psoas muscle index, and visceral/subcutaneous fat ratio were significant prognostic factors for overall survival (P = 0.008, P = 0.04, P = 0.04, P = 0.02, and P = 0.02, respectively). In the multivariate analysis, age and psoas muscle index were significant prognostic factors for overall survival (P = 0.01 and P = 0.03, respectively). The 5-year overall survival rates for the high and low psoas muscle index groups were 79.6% [95% confidence interval (CI), 67.1-94.5%] and 66.2% (95% CI, 54.1-81.1%), respectively; whereas, the 10-year overall survival rates were 61.9% (95% CI, 42.0-91.4%) and 25.3% (95% CI, 8.6-74.2%), respectively.

CONCLUSION

Sarcopenia was related to poor overall survival in patients with locally advanced NSCLC undergoing trimodality therapy. Assessment of body composition prior to treatment may provide important information for formulating rational therapeutic strategies.

The prognostic impact of sarcopenia on elderly patients undergoing pulmonary resection for non-small cell lung cancer

PURPOSE

The number of elderly patients who undergo surgery is increasing, even though they are at a high risk due to a decreased physical strength. Furthermore, sarcopenia is generally associated with a poor prognosis in patients with non-small cell lung cancer (NSCLC).

METHODS

This study included NSCLC patients  ≥ 65 years old who underwent pulmonary resection in our hospital between 2012 and 2015. Sarcopenia was assessed using the psoas muscle mass index based on computed tomography at the level of the third lumbar vertebra. We elucidated the impact of sarcopenia on short- and long-term outcomes after surgery.

RESULTS

We enrolled 259 patients, including 179 with sarcopenia. Patients with sarcopenia before surgery tended to have postoperative complications (p = 0.0521), although they did not show a poor prognosis. In patients with sarcopenia, a multivariate analysis revealed that postoperative complications and the progression of sarcopenia 1 year after surgery were significant risk factors for a poor prognosis (p = 0.0169 and 0.00370, respectively).

CONCLUSIONS

The progression of sarcopenia after surgery is associated with a poor prognosis in elderly NSCLC patients with sarcopenia. A strategy to prevent postoperative progressive sarcopenia may be necessary for improving the clinical outcome of this population.

Impact of Sarcopenia on Survival in Patients With Early-Stage Lung Cancer Treated With Stereotactic Body Radiation Therapy

Background

Sarcopenia has been associated with poor survival among cancer patients. Normalized total psoas area (NTPA) has been used as a surrogate for defining sarcopenia. Few data exist characterizing the impact of sarcopenia and other metrics of fitness on clinical outcomes in patients with early-stage non-small cell lung cancer (NSCLC) treated non-invasively with stereotactic body radiotherapy (SBRT).

Methods

To assess the association between sarcopenia and clinical outcomes, we conducted a retrospective analysis of consecutive patients treated with SBRT from 2013 to 2019 . Overall survival (OS), local failure free survival (LFS), distant failure free survival (DFS), NTPA, body mass index (BMI), and Charlson comorbidity index (CCI) were included for analysis. NTPA was calculated by measuring the psoas volume at the L3 vertebra and normalizing for patient height and gender. Survival functions were evaluated using the Kaplan-Meier method. Log-rank test and Cox-proportional hazards were performed for categorical and continuous variables, respectively. Significance was set as p < 0.05.

Results

A total of 91 patients met the criteria. The median age was seven years and Karnofsky Performance Status score (KPS) was 80 (range: 60-100). Approximately 79% of patients had T1 tumors. Median radiation dose and number of fractions were 60 Gy (range: 45-60) and 5 fractions (range: 3-5). Median NTPA was 531.16 mm²/m² (range: 90.4-1356.2). After normalization (sarcopenia: <385 mm²/m², female; <585 mm²/m^2, male), 39 patients (42.8%) had sarcopenia. NTPA had no association with OS (p = 0.7), LFS (p = 0.9), or DFS (p = 0.5). Increasing BMI was associated with improved OS (HR 0.90, 95% CI 0.83-0.98). With a median follow-up of 23.4 months, median OS was 60, 60, and 45.9 months (p = 0.37) in all patients, non-sarcopenic patients, and sarcopenic patients, respectively.

Conclusion

Sarcopenia was not associated with OS, LFS, or DFS. Increasing BMI is associated with improved OS. Future, prospective work is needed to define the impact of sarcopenia and other fitness metrics on clinical outcomes among NSCLC patients treated non-invasively with SBRT.

Cancer cachexia in thoracic malignancy: a narrative review

PURPOSE OF REVIEW

Thoracic malignancies are amongst the most lethal of all cancers. Cancer cachexia lacks unanimously accepted diagnostic criteria, and therefore is referenced to as a conceptual framework whereby cancer cachexia is 'an ongoing loss of skeletal muscle mass (termed sarcopenia), with or without loss of fat mass that cannot be reversed by conventional nutritional support and leads to progressive functional impairment'. This review summarises the current evidence base in this field, including imaging techniques currently used to define sarcopenia, inflammatory and metabolic changes associated with the syndrome and ongoing research into potential treatment strategies.

RECENT FINDINGS

Sarcopenia is a key component of the cancer cachexia syndrome. It is common in patients with both early-stage and advanced NSCLC. Patients with sarcopenia have more treatment-related side effects and poorer overall survival compared with nonsarcopenic patients.

SUMMARY

Early identification of cancer cachexia may facilitate stratification of patients most-at-risk and initiation of emerging anticachexia treatments. If these are proven to be effective, this strategy has the potential to improve tolerance to anti-cancer therapies, improving the quality of life, and perhaps the survival, of patients with thoracic malignancies.

Body Composition and Biochemical Markers of Nutrition in Non-dialysis-Dependent Chronic Kidney Disease Patients

The aim of this study was to examine the body composition in stages 3b to 5 of chronic kidney disease. There were 149 patients included in the study, with the mean age of 65.5 ± 16.5 years, body mass index (BMI) of 29.4 ± 5.6 kg/m², and estimated glomerular filtration rate (eGFR) of 23.2 ± 9.3/min/1.73m². They remained with dialysis. Body composition was measured using bioimpedance spectroscopy, and handgrip strength was measured with a hydraulic dynamometer. The main biochemical markers assessed consisted of serum protein, albumin, prealbumin, high-sensitivity C-reactive protein (hsCRP), and interleukin (IL)-6 content. We found that 39% of patients were overweight and 41% were obese. Obesity was more prevalent in stage 3b of chronic kidney disease than in stages 4-5 in women and in patients older than 60 years of age. Thirty-eight percent of the study population were sarcopenic, of whom 20% presented a sarcopenic obesity phenotype. There were significant associations between lean tissue index (LTI) and serum prealbumin content and handgrip strength. Fat tissue index (FTI) was associated and hsCRP, serum protein, body mass index (BMI), waist-hip ratio, and waist-to-height ratio. There were inverse associations between FTI-LTI and LTI-age. We conclude that the prevalence of obesity in non-dialysis-dependent patients with chronic kidney disease is higher than that in the general population. Earlier stages of chronic kidney disease are associated with a higher prevalence of obesity.

Prognostic Value of Sarcopenia in Lung Cancer: A Systematic Review and Meta-analysis

BACKGROUND

Evidence regarding the association between sarcopenia (skeletal muscle depletion) and outcomes in patients with lung cancer varies across studies. We aimed to systematically review the prognostic value of sarcopenia in lung cancer.

METHODS

We searched Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials through July 23, 2018 to identify retrospective or prospective cohort studies. We applied the Quality in Prognostic Studies instrument to assess the risk of bias in individual studies. We examined the heterogeneity and publication bias and performed subgroup analyses and sensitivity analyses.

RESULTS

We included 13 studies (1,810 participants). The pooled prevalence of sarcopenia was 43% in patients with non-small cell lung cancer (NSCLC) and 52% in patients with small cell lung cancer (SCLC). Sarcopenia was associated with a shorter overall survival (OS) in patients with lung cancer (hazard ratio [HR], 2.23; 95% CI, 1.68-2.94). This association existed for both NSCLC (HR, 2.57; 95% CI, 1.79-3.68) and SCLC (HR, 1.59; 95% CI, 1.17-2.14). Sarcopenia was an independent predictor of shorter OS in both stage I-II NSCLC (HR, 3.23; 95% CI, 1.68-6.23) and stage III-IV NSCLC (HR, 2.19; 95% CI, 1.14-4.24). However, sarcopenia was not an independent predictor of disease-free survival in patients with NSCLC (HR, 1.28; 95% CI, 0.44-3.69).

CONCLUSIONS

Sarcopenia is highly prevalent in patients with lung cancer (approximately one in two) and an important predictor of impaired OS in patients with SCLC or with different stages of NSCLC.