Significance of preoperative evaluation of skeletal muscle index and immune-nutritional status for patients with early-stage non-small cell lung cancer

OBJECTIVES

Sarcopenia involves several mechanisms, including age-related changes, nutritional deficiencies, and inflammation, and is associated with unfavorable clinical outcomes. However, the significance of skeletal muscle index (SMI) and immune-nutritional status for patients with early-stage non-small cell lung cancer (NSCLC) remains unclear. This retrospective study was performed to investigate associations between preoperative SMI based on computed tomography (CT) at the L1 level and immune-nutritional status, and whether these factors correlated with surgical outcomes.

METHODS

We retrospectively investigated 386 patients with stage I-II NSCLC who underwent curative anatomical pulmonary resection. SMI was assessed on CT at the L1 level and patients were divided into low-SMI (n = 97) and high-SMI (n = 289) groups. We examined the significance of SMI for postoperative outcomes and evaluated correlations between SMI and clinical characteristics, including immune-nutritional status.

RESULTS

Low SMI was significantly associated with body mass index and geriatric nutritional risk index. Five-year overall survival rate was significantly lower in the low-SMI group (66.0%) than in the high-SMI group (82.2%, P = 0.004). Multivariate analysis revealed SMI (hazard ratio [HR] 1.850; 95% confidence interval [CI] 1.091-3.135; P = 0.022) and prognostic nutritional index (PNI) (HR 2.031; 95% CI 1.231-3.352; P = 0.006) as independent predictors of overall survival. Low SMI correlated significantly with postoperative complications (P = 0.024).

CONCLUSIONS

Low preoperative SMI based on CT at the L1 level appears associated with poor prognosis and postoperative complications among patients with early-stage NSCLC. PNI is also an independent prognostic factor for surgical outcomes.

Influence of reduced muscle mass and quality on ventilator weaning and complications during intensive care unit stay in COVID-19 patients

BACKGROUND & AIMS

Sarcopenia, a loss of muscle mass, quality and function, which is particularly evident in respiratory muscles, has been associated with many clinical adverse outcomes. In this study, we aimed at evaluating the role of reduced muscle mass and quality in predicting ventilation weaning, complications, length of intensive care unit (ICU) and of hospital stay and mortality in patients admitted to ICU for SARS-CoV-2-related pneumonia.

METHODS

This was an observational study based on a review of medical records of all adult patients admitted to the ICU of a tertiary hospital in Milan and intubated for SARS-CoV-2-related pneumonia during the first wave of the COVID-19 pandemic. Muscle mass and quality measurement were retrieved from routine thoracic CT scans, when sections passing through the first, second or third lumbar vertebra were available.

RESULTS

A total of 81 patients were enrolled. Muscle mass was associated with successful extubation (OR 1.02, 95% C.I. 1.00-1.03, p = 0.017), shorter ICU stay (OR 0.97, 95% C.I. 0.95-0.99, p = 0.03) and decreased hospital mortality (HR 0.98, 95% C.I. 0.96-0.99, p = 0.02). Muscle density was associated with successful extubation (OR 1.07, 95% C.I. 1.01-1.14; p = 0.02) and had an inverse association with the number of complications in ICU (Β -0.07, 95% C.I. -0.13 - -0.002, p = 0.03), length of hospitalization (Β -1.36, 95% C.I. -2.21 - -0.51, p = 0.002) and in-hospital mortality (HR 0.88, 95% C.I. 0.78-0.99, p = 0.046).

CONCLUSIONS

Leveraging routine CT imaging to measure muscle mass and quality might constitute a simple, inexpensive and powerful tool to predict survival and disease course in patients with COVID-19. Preserving muscle mass during hospitalisation might have an adjuvant role in facilitating remission from COVID-19.

CT-Derived Body Composition Values and Complications After Pneumonectomy in Lung Cancer Patients: Time for a Sex-Related Analysis?

Purpose

This study aimed to assess if CT-derived body composition values and clinical characteristics are associated with the risk of postsurgical complications in men and women who underwent pneumonectomy for lung cancer.

Materials and Methods

Patients who underwent pneumonectomy between 2004 and 2008 were selected. The ethics committee approved this retrospective study with waiver of informed content. Main clinical data collected were sex, age, weight and height to calculate body mass index (BMI), albumin, C-reactive protein, smoking status, side, sarcopenia, presurgical treatments, reoperation, and complications within 30 days after pneumonectomy, classified as: lung complications, cardiac complications, other complications, and any complication. From an axial CT image at the level of L3, automatic segmentations were performed to calculate skeletal muscle area (SMA), skeletal muscle density, subcutaneous adipose tissue, and visceral adipose tissue. Skeletal muscle index was calculated as SMA/square height. Univariate and multivariate logistic regression analyses were performed to estimate the risk of any complication, both on the total population and in a by sex subgroup analysis. All tests were two tailed and considered significant at 5% level.

Results

A total of 107 patients (84 men and 23 women) were included. Despite no significant differences in BMI, there were significant differences of body composition values in muscle and adipose tissue parameters between men and women, with women being significantly more sarcopenic than men (p = 0.002). Separate analyses for men and women showed that age and SMA were significantly associated with postoperative complications in men (p = 0.03 and 0.02, respectively).

Conclusions

Body composition measurements extracted from routine CT may help in predicting complications after pneumonectomy, with men and women being different in quantity and distribution of muscle and fat, and men significantly more prone to postpneumonectomy complications with the increase of age and the decrease of skeletal muscle area.

Muscle Quality Predicts Outcomes after Surgery for Early-Stage Non-Small-Cell Lung Cancer

Purpose: This study investigated the impact of skeletal muscle quality on the outcomes of patients undergoing surgery for early-stage non–small-cell lung cancer (NSCLC).

Methods: A total of 98 patients with pathological stage I–II NSCLC who underwent lobectomy or segmentectomy were retrospectively analyzed. Along with skeletal muscle quantity, muscle quality was evaluated by intramuscular adipose tissue content (IMAC) at the first lumbar vertebral level; a higher IMAC indicates lower skeletal muscle quality. Patients were divided into two groups according to the gender-specific quartiles of IMAC, and the prognostic impact of IMAC was investigated.

Results: No significant differences in the body and skeletal mass indices, which indicate skeletal muscle quantity, were observed between patients with high and those with normal IMAC. Patients with high IMAC (n = 23) showed a significantly poorer prognosis in overall and disease-specific survivals than those with normal IMAC (n = 75; P <0.001 and P = 0.048, respectively). In a bivariate analysis that included other clinicopathological factors, a high IMAC was independently associated with worse overall survival.

Conclusion: The skeletal muscle quality evaluated by IMAC could be used to predict survival risk after surgery for early-stage NSCLC.

Sarcopenia on preoperative chest computed tomography predicts cancer-specific and all-cause mortality following pneumonectomy for lung cancer: A multicenter analysis

Background

Mortality risk prediction in patients undergoing pneumonectomy for non‐small cell lung cancer (NSCLC) remains imperfect. Here, we aimed to assess whether sarcopenia on routine chest computed tomography (CT) independently predicts worse cancer‐specific (CSS) and overall survival (OS) following pneumonectomy for NSCLC.

Methods

We included consecutive adults undergoing standard or carinal pneumonectomy for NSCLC at Massachusetts General Hospital and Heidelberg University from 2010 to 2018. We measured muscle cross‐sectional area (CSA) on CT at thoracic vertebral levels T8, T10, and T12 within 90 days prior to surgery. Sarcopenia was defined as T10 muscle CSA less than two standard deviations below the mean in healthy controls. We adjusted time‐to‐event analyses for age, body mass index, Charlson Comorbidity Index, forced expiratory volume in 1 second in % predicted, induction therapy, sex, smoking status, tumor stage, side of pneumonectomy, and institution.

Results

Three hundred and sixty‐seven patients (67.4% male, median age 62 years, 16.9% early‐stage) underwent predominantly standard pneumonectomy (89.6%) for stage IIIA NSCLC (45.5%) and squamous cell histology (58%). Sarcopenia was present in 104 of 367 patients (28.3%). Ninety‐day all‐cause mortality was 7.1% (26/367). After a median follow‐up of 20.5 months (IQR, 9.2–46.9), 183 of 367 patients (49.9%) had died. One hundred and thirty‐three (72.7%) of these deaths were due to lung cancer. Sarcopenia was associated with shorter CSS (HR 1.7, p = 0.008) and OS (HR 1.7, p = 0.003).

Conclusions

This transatlantic multicenter study confirms that sarcopenia on preoperative chest CT is an independent risk factor for CSS and OS following pneumonectomy for NSCLC.

The use of alternate vertebral levels to L3 in computed tomography scans for skeletal muscle mass evaluation and sarcopenia assessment in patients with cancer: a systematic review

Body composition measurement using diagnostic computed tomography (CT) scans has emerged as a method to assess sarcopenia (low muscle mass) in oncology patients. Assessment of skeletal muscle mass (SMM) using the cross-sectional area of a single vertebral slice (at lumbar L3) in a CT scan is correlated with whole-body skeletal muscle volume. This method is used to assess CT-defined sarcopenia in patients with cancer, with low SMM effecting outcomes. However, as diagnostic scans are based on tumour location, not all include L3. We evaluated the evidence for the use of alternate vertebral CT slices for SMM evaluation when L3 is not available. Five electronic databases were searched from January 1996 to April 2020 for studies using CT scan vertebral slices above L3 for SM measurement in adults with cancer (solid tumours). Validation with whole-body SMM, rationale for the chosen slice and sarcopenia cut-off values were investigated. Thirty-two studies were included, all retrospective and cross-sectional in design. Cervical, thoracic and lumbar slices were used (from C3 to L1), with no validation of whole-body SMM using CT scans. Alternate slices were used in lung, and head and neck cancer patients. Sarcopenia cut-off values were reported in 75 % of studies, with differing methods, with or without sex-specific values, and a lack of consensus. Current evidence is inadequate to provide definitive recommendations for alternate vertebral slice use for SMM evaluation in cancer patients. Variation in sarcopenia cut-offs warrants more robust investigation, in order for risk stratification to be applied to all patients with cancer.

Respiratory strength and pectoralis muscle mass as measures of sarcopenia: Relation to outcomes in resected non-small cell lung cancer

OBJECTIVES

Physical biomarkers to stratify patients with lung cancer into subtypes predictive of outcome beyond tumor-related characteristics are underexplored. This study was designed to investigate the clinical utility of preoperative sarcopenia based on respiratory strength and pectoralis muscle mass to predict the risk of death.

METHODS

This retrospective study included 346 consecutive patients undergoing curative-intent resection of non-small cell lung cancer from 2009 to 2013. Respiratory strength and muscle mass were assessed by peak expiratory flow rate and pectoralis muscle index (pectoralis muscle area/body mass index) using preoperative spirometry and chest axial images, respectively. Sarcopenia cutoff points were defined by gender-specific medians of peak expiratory flow rates and pectoralis muscle indices. Survival was compared between patients with sarcopenia and patients without.

RESULTS

Sarcopenia was present in 98 patients (28.3%) and was significantly associated with advancing age (P < .001). Patients with sarcopenia exhibited worse 5-year overall survival compared with patients without sarcopenia (69.9% vs 87.2%, P < .001). Multivariate analysis revealed that sarcopenia was an independent adverse prognostic factor (hazard ratio, 1.88; 95% confidence interval, 1.09-3.24; P = .023) after adjustment for gender, age, smoking status, coronary heart disease, diffusing capacity for carbon monoxide, neutrophil-to-lymphocyte ratio, albumin, histologic type, and pathologic stage.

CONCLUSIONS

Preoperative sarcopenia as identified by the criteria of low respiratory strength and reduced pectoralis muscle mass is significantly associated with poor overall survival. This may help to develop more individualized management strategies and optimize longitudinal care for patients.

Identifying sarcopenia in advanced non-small cell lung cancer patients using skeletal muscle CT radiomics and machine learning

Background

Sarcopenia has been confirmed as a poor prognostic indicator of lung cancer. However, the lack of abdominal computed tomography (CT) hindered the application to assess the status of sarcopenia. The purpose of this study was to assess the ability of chest CT radiomics combined with machine learning classifiers to identify sarcopenia in advanced non‐small cell lung cancer (NSCLC) patients.

Methods

This study retrospectively analyzed CT images of 99 patients with NSCLC. Skeletal muscle radiomics were extracted from a single axial slice of the chest CT scan at the 12th thoracic vertebrae level. In total, 854 radiomic and clinical features were obtained from each patient. Feature selection was conducted with FeatureSelector module, optimal key features were fed into the lightGBM classifier for model construction, and Bayesian optimization was adopted to tune hyperparameters. The model's performance was evaluated by specificity, sensitivity, accuracy, precision, F1‐score, Matthew's correlation coefficient (MCC), Cohen's kappa coefficient (Kappa), and AUC.

Results

A total of 40 patients were found to have sarcopenia. Five optimal features were selected. In the base lightGBM model, the specificity, sensitivity, accuracy, precision, F1‐score, AUC, MCC, Kappa of validation set were 0.889, 0.750, 0.833, 0.818, 0.783, 0.819, 0.649, 0.648, respectively. After Bayesian hyperparameter tuning, the optimized lightGBM model achieved better prediction performance, and the corresponding values were 0.944, 0.833, 0.900, 0.909, 0.870, 0.889, 0.791, 0.789, respectively.

Conclusions

Chest CT‐based radiomics has the potential to identify sarcopenia in NSCLC patients with the lightGBM classifier, and the optimal lightGBM model via Bayesian hyperparameter tuning demonstrated better performance.

Key points

Significant findings of the study

Our study demonstrates that chest CT‐based radiomics combined with lightGBM classifier has the ability to identify sarcopenia in NSCLC patients.

What this study adds

Skeletal muscle radiomics would be a potential biomarker for sarcopenia identity in NSCLC patients.

Prognostic significance of low pectoralis muscle mass on preoperative chest computed tomography in localized non-small cell lung cancer after curative-intent surgery

OBJECTIVES

The impact of sarcopenia on the outcome in patients following resection of non-small cell lung cancer is yet to be fully determined. This study aimed to evaluate the clinical utility of a computed tomography-based pectoralis muscle assessment, which reflects sarcopenia, to predict the risk of postoperative outcomes.

MATERIALS AND METHODS

This retrospective study included 347 consecutive patients undergoing curative-intent resection of non-small cell lung cancer from 2009 to 2013. The pectoralis muscle index (pectoralis muscle area/body mass index) was assessed at the level of the fourth thoracic vertebra on chest axial images. The primary outcomes were compared between the lowest gender-specific quintile (sarcopenia) and the other quintiles according to the index. The prognostic significance of low pectoralis muscle index was calculated by the Cox proportional hazards regression model. A propensity score matching analysis was performed to adjust the differences in clinical characteristics.

RESULTS

Sixty-nine patients were identified with sarcopenia according to the lowest gender-specific quintile of pectoralis muscle index. Patients with sarcopenia exhibited worse 5-year overall survival rate compared with patients without sarcopenia (64.2 % vs. 86.7 %, P < 0.001). Even in stage I non-small cell lung cancer, the rate of 5-year overall survival in the sarcopenia group was lower than that in the non-sarcopenia group (74.2 % vs. 92.4 %, P = 0.001). Multivariate analysis revealed that low pectoralis muscle index was independently associated with adverse overall survival (hazard ratio: 2.09, 95 % confidence interval: 1.20-3.62, P = 0.009). After propensity score matching, the prognostic impact of sarcopenia based on low pectoralis muscle index was also robust for overall survival (hazard ratio: 3.23, 95 % confidence interval: 1.38-7.60, P = 0.007).

CONCLUSIONS

Low pectoralis muscle index was significantly associated with poor long-term outcomes in patients with localized non-small cell lung cancer after curative surgery. This may help assist preoperative risk stratification and longitudinal management after surgery.

Psoas muscle mass in patients undergoing lung cancer surgery: a prognostic difference between squamous cell carcinoma and adenocarcinoma

BACKGROUND

Psoas muscle mass is a surrogate marker for sarcopenia: a depletion of skeletal muscle mass. This study was conducted to elucidate the prognostic significance of the psoas muscle index (PMI: cross-sectional area of the bilateral psoas muscle at the umbilical level on computed tomography/height² [cm²/m²]) in patients undergoing surgery for lung squamous cell carcinoma (SCC) and lung adenocarcinoma (ADC).

METHODS

One hundred and sixty-five patients with SCC and 556 patients with ADC who underwent R0 resection between 2007 and 2014 were reviewed for analysis. In SCC patients, the mean value (standard deviation) of the PMI was 6.15 (1.49) in men and 4.65 (1.36) in women. Among ADC patients, the PMI was 7.12 (1.60) in men and 5.29 (1.22) in women. Clinicopathological characteristics as well as the survival were evaluated.

RESULTS

The PMI was associated with the age, body mass index (BMI), and serum albumin. In the multivariable Cox regression analysis, after adjusting for age, BMI, serum albumin, sex, pathological stage, and diffusing capacity for carbon monoxide, the PMI showed a significant association with the overall survival (OS) and disease-free survival (DFS) in SCC patients (hazard ratios 0.50 and 0.56, 95% confidence intervals 0.39-0.65 and 0.45-0.71, respectively). On the other hand, in ADC patients, the PMI had no impact on the OS or DFS.

CONCLUSIONS

The PMI was significantly associated with the survival of lung SCC patients, but not of lung ADC patients, suggesting the presence of a previously unidentified relationship between skeletal muscle and lung SCC progression.

Risk factors and cancer recurrence associated with postoperative complications after thoracoscopic lobectomy for clinical stage I non-small cell lung cancer

Background

Minimally invasive thoracoscopic lobectomy is the recommended surgery for clinical stage I non‐small cell lung cancer (NSCLC). The purpose of this study was to identify the risk factors, including sarcopenia, for postoperative complications in patients undergoing a complete single‐lobe thoracoscopic lobectomy for clinical stage I NSCLC, as well as the impact of complications on disease‐free survival.

Methods

We retrospectively investigated 173 patients with pathologically‐diagnosed NSCLC who underwent curative thoracoscopic lobectomies between April 2013 and March 2018. Sarcopenia was assessed using the psoas muscle index calculated from preoperative computed tomography images at the third lumbar vertebral level.

Results

Complications developed in 38 (22%) patients, including 21 with prolonged air leak. In univariate analysis, the significant risk factors for complications were advanced age, male sex, higher Charlson Comorbidity Index (CCI) score, lower cholinesterase, lower albumin, higher creatinine level, pleural adhesion, operative time ≥ five hours, nonadenocarcinoma cancer, and larger tumor size. Multivariate analysis showed that age ≥ 75 years (P = 0.002) and pleural adhesion (P = 0.026) were significant independent risk factors for complications. Compared with the patient group without complications, postoperative complications were independently associated with shorter disease‐free survival (P = 0.01).

Conclusions

Advanced age and pleural adhesion were independent risk factors for complications after complete single‐lobe thoracoscopic lobectomies for clinical stage I NSCLC, and postoperative complications were statistically associated with poor prognosis. Surgical teams should ensure an experienced surgeon leads the operation for patients at higher risk to avoid prolonged postoperative hospitalization and a possible poor prognosis.