Prognostic value of paravertebral muscle density in patients with spinal metastases from gastrointestinal cancer

Sarcopenia and the management of spinal disease in the elderly

Sarcopenia, generally defined by the loss of skeletal mass and function, may disproportionately affect elderly individuals and heavily influence spinal disease. Muscle atrophy is associated with myriad clinical problems, including thoracic kyphosis, increased sagittal vertical axis (SVA), spinal implant failures, and postoperative complications. As such, the aim of this narrative review is to synthesize pertinent literature detailing the intersection between sarcopenia and the impact of sarcopenia on the management of spine disease. Specifically, we focus on the domains of etiology, diagnosis and assessment, impact on the cervical and lumbar spine, spinal augmentation procedures, neoplastic disease, whiplash injury, and recovery/prevention. A narrative review was conducted by searching the PubMed and Google Scholar databases from inception to July 12, 2024, for any cohort studies, systematic reviews, or randomized controlled trials. Case studies and conference abstracts were excluded. Diagnosis of sarcopenia relies on the assessment of muscle strength and quantity/quality. Strength may be assessed using clinical tools such as gait speed, timed up and go (TUG) test, or hand grip strength, whereas muscle quantity/quality may be assessed via computed tomography (CT scan), magnetic resonance imaging (MRI), and dual-energy X-ray absorptiometry (DXA scan). Sarcopenia has a generally negative impact on the clinical course of those undergoing cervical and lumbar surgery, and may be predictive of mortality in those with neoplastic spinal disease. In addition, severe acceleration-deceleration (whiplash) injuries may result in cervical extensor muscle atrophy. Intervention and recovery measures include nutrition or exercise therapy, although the evidence for nutritional intervention is lacking. Sarcopenia is a widely prevalent pathology in the advanced-age population, in which the diagnostic criteria, impact on spinal pathology, and recovery/prevention measures remain understudied. However, further understanding of this therapeutically challenging pathology is paramount, as surgical outcome may be heavily influenced by sarcopenia status.

Use of 3D-CT-derived psoas major muscle volume in defining sarcopenia in colorectal cancer

BACKGROUND

Sarcopenia is characterized by reduced skeletal muscle volume and is a condition that is prevalent among elderly patients and associated with poor prognosis as a comorbidity in malignancies. Given the aging population over 80 years old in Japan, an understanding of malignancies, including colorectal cancer (CRC), complicated by sarcopenia is increasingly important. Therefore, the focus of this study is on a novel and practical diagnostic approach of assessment of psoas major muscle volume (PV) using 3-dimensional computed tomography (3D-CT) in diagnosis of sarcopenia in patients with CRC.

METHODS

The subjects were 150 patients aged ≥ 80 years with CRC who underwent primary tumor resection at Juntendo University Hospital between 2004 and 2017. 3D-CT measurement of PV and conventional CT measurement of the psoas major muscle cross-sectional area (PA) were used to identify sarcopenia (group S) and non-sarcopenia (group nS) cases. Clinicopathological characteristics, operative results, postoperative complications, and prognosis were compared between these groups.

RESULTS

The S:nS ratios were 15:135 for the PV method and 52:98 for the PA method. There was a strong positive correlation (r = 0.66, p < 0.01) between PVI (psoas major muscle volume index) and PAI (psoas major muscle cross-sectional area index), which were calculated by dividing PV or PA by the square of height. Surgical results and postoperative complications did not differ significantly in the S and nS groups defined using each method. Overall survival was worse in group S compared to group nS identified by PV (p < 0.01), but not significantly different in groups S and nS identified by PA (p = 0.77). A Cox proportional hazards model for OS identified group S by PV as an independent predictor of a poor prognosis (p < 0.05), whereas group S by PA was not a predictor of prognosis (p = 0.60).

CONCLUSIONS

The PV method for identifying sarcopenia in elderly patients with CRC is more practical and sensitive for prediction of a poor prognosis compared to the conventional method.

Evaluation of muscle mass and intramuscular fatty infiltration in dogs with hypercortisolism and their association with prognosis

BACKGROUND

Muscle atrophy and intramuscular fatty infiltration, as well as their association with prognosis, have not been quantified in dogs with spontaneous hypercortisolism (HC).

OBJECTIVE

To quantitatively evaluate muscle atrophy and IM fatty infiltration in dogs with HC and determine their prognostic impact.

ANIMALS

Fifty-three dogs with HC and 66 control dogs without HC.

METHODS

Retrospective cohort study. Medical records and computed tomography images obtained between 2014 and 2021 were evaluated. Kaplan-Meier curves and log-rank tests were used to analyze the effect of muscle atrophy and IM fatty infiltration on the prognosis of dogs with HC.

RESULTS

Dogs with HC showed lower visually measured cross-sectional area (VCSA) and cross-sectional area based on attenuation (HCSA) than control dogs (median [interquartile range {IQR}]: 50.3 mm2/mm [36.2-67.8] vs 66.7 mm2/mm [48.0-85.9]; P < .001; 30.4 mm2/mm [13.7-57.2] vs 54.8 mm2/mm [39.7-71.5]; P < .001, respectively). Dogs with HC had lower epaxial muscle attenuation (L3HU) than control dogs (median [IQR]: 21.2 Hounsfield [HU] [12.4-28.2] vs 33.2 HU [22.6-43.6]; P < .001). Dogs with HC with lower HCSA or L3HU had shorter survival (median [IQR]: 670 days [222-673] vs 949 days [788-1074], P < .01; 523 days [132-670] vs 949 days [756-1074], P < .01, respectively) but not lower VCSA (median [IQR]: 673 days [132-788] vs 949 days [523 to not applicable]; P = .30).

CONCLUSION AND CLINICAL IMPORTANCE

Hypercortisolism in dogs causes muscle atrophy and IM fatty infiltration and is associated with poor prognosis.

Lumbar muscle involvement in the occurrence of osteoporotic vertebral fracture

Objective

To determine if a lumbar musculature deficiency (paravertebral - PVM - and psoas - PM - muscles) is associated with a higher prevalence of vertebral fractures in osteoporotic patients.

Methods

To constitute the fracture group, data were collected retrospectively from patients with one or more recent osteoporotic vertebral fractures between T10 and L5 such as non-injected computerized tomography (CT), dual-energy X-ray absorptiometry (DXA). A control group was made by matching the patients on age, bone mineral density measured by DXA and gender. We analyzed PM and PVM atrophy based on cross-sectional area (CSA) adjusted to the body area as well as fatty infiltration on a 3-level scale and the average muscle density in Hounsfield units (HU).

Results

One hundred seventeen patients were included in each group. The fracture group had a lower PVM CSA than the control group (2197.92 ± 460.19 versus 2335.20 ± 394.42 mm2.m-2, respectively p = 0.015), but there was no significant difference in the PM (746.92 ± 197.89 versus 731.74 ± 215.53 mm2.m-2, respectively p = 0.575). The fracture group had a higher grade of fatty infiltration than the control group (PM: 1.3 ± 0.46 versus 1.07 ± 0.25, p < 0.001; PVM: 1.93 ± 0.5 versus 1.74 ± 0.5, p = 0.003) and a lower average muscle density (PM: 26.99 ± 12.83 versus 33.91 ± 8.12 HU, p < 0.001; PVM: 3.42 ± 21.06 versus 12.94 ± 18.88 HU, p < 0.001).

Conclusion

This study shows an association between a lack of axial musculature and the occurrence of osteoporotic vertebral fractures. Preventive strengthening exercises could be proposed to osteoporotic patients.

Psoas muscle index and psoas muscle density are associated with functional status in patients with degenerative lumbar spinal stenosis

BACKGROUND

The factors affecting lumbar spinal function in patients with degenerative lumbar spinal stenosis (DLSS) are still unclear.

OBJECTIVE

This study explored psoas major muscle morphology in patients with DLSS and its association with their functional status.

METHODS

A retrospective study was conducted on 288 patients with DLSS and 260 control subjects. Psoas major muscle evaluation included three morphometric parameters at the L3/4 disc level: psoas major index (PMI), muscle attenuation, and psoas major morphological changes (MPM). The association between psoas major morphology and functional status was assessed using the Oswestry disability index (ODI).

RESULTS

Both female and male patients with DLSS had a higher PMI and lower muscle attenuation. PMI and muscle attenuation were inversely correlated with age in the DLSS group. After multivariable analyses, the PMI and psoas major muscle attenuation were positively correlated with patients' functional status.

CONCLUSION

The PMI and muscle attenuation were positively correlated with functional status in patients with DLSS. These findings have important implications for physiotherapy programs of postoperative rehabilitation and conservative management of DLSS.

Comparison of frailty metrics and the Charlson Comorbidity Index for predicting adverse outcomes in patients undergoing surgery for spine metastases

OBJECTIVE

Frailty-the state defined by decreased physiological reserve and increased vulnerability to physiological stress-is exceedingly common in oncology patients. Given the palliative nature of spine metastasis surgery, it is imperative that patients be healthy enough to tolerate the physical insult of surgery. In the present study, the authors compared the association of two frailty metrics and the widely used Charlson Comorbidity Index (CCI) with postoperative morbidity in spine metastasis patients.

METHODS

A retrospective cohort of patients who underwent operations for spinal metastases at a comprehensive cancer center were identified. Data on patient demographic characteristics, disease state, medical comorbidities, operative details, and postoperative outcomes were collected. Frailty was measured with the modified 5-item frailty index (mFI-5) and metastatic spinal tumor frailty index (MSTFI). Outcomes of interest were length of stay (LOS) greater than the 75th percentile of the cohort, nonroutine discharge, and the occurrence of ≥ 1 postoperative complication.

RESULTS

In total, 322 patients were included (mean age 59.5 ± 12 years; 56.9% of patients were male). The mean ± SD LOS was 11.2 ± 9.9 days, 44.5% of patients had nonroutine discharge, and 24.0% experienced ≥ 1 postoperative complication. On multivariable analysis, increased frailty on mFI-5 and MSTFI was independently predictive of all three outcomes: prolonged LOS (OR 1.67 per point, 95% CI 1.06-2.63, p = 0.03; and OR 1.63 per point, 95% CI 1.29-2.05, p < 0.01, respectively), nonroutine discharge (OR 2.65 per point, 95% CI 1.74-4.04, p < 0.01; and OR 1.69 per point, 95% CI 1.36-2.11, p < 0.01), and ≥ 1 complication (OR 1.95 per point, 95% CI 1.23-3.09, p = 0.01; and OR 1.41 per point, 95% CI 1.12-1.77, p < 0.01). CCI was found to be independently predictive of only the occurrence of ≥ 1 postoperative complication (OR 1.45 per point, 95% CI 1.22-1.72, p < 0.01).

CONCLUSIONS

Frailty measured with either mFI-5 or MSTFI scores was a more robust independent predictor of adverse postoperative outcomes than the more widely used CCI. Both mFI-5 and MSTFI were significantly associated with prolonged LOS, higher complication rates, and nonroutine discharge. Further investigation in a prospective multicenter cohort is merited.

Sarcopenia in Patients With Spinal Metastasis: A Systematic Review and Meta-Analysis of Retrospective Cohort Studies

Background

As a metastasis cancer that happens up to 70% of the cancer patients, spinal metastasis is drawing attention for its significant impairment to health. There exist several predictive models designed to estimate mortality in spinal metastasis patients but they are reported with limited accuracy. In recent years, some retrospective cohort studies have been carried out to associate sarcopenia with mortality in spinal metastasis.

Introduction

As a risk factor leading to adverse events in many diseases, sarcopenia was considered to significantly impact on patients with spinal metastasis in mortality by some scientists. We aimed to look through the current evidence and use statistic measures to value the role of sarcopenia in spinal metastasis. In this study, we are going to perform a systematic review and meta-analysis of available retrospective cohort studies where sarcopenia is assessed for outcomes in spinal metastasis patients.

Methods

On October 7, 2021, we performed a search in PubMed, Embase, and the Cochrane Library. We set no restrictions on language, date or areas. Results were expressed as hazard ratio (HR) or odds ratio (OR) with 95% CI by random effects model. Sensitivity analyses were performed to explore sources of heterogeneity and stability of results.

Results

Of the 4,196 papers screened, 10 retrospective cohort studies were included, with a total of 1,674 patients. Results showed that sarcopenia was associated with higher overall mortality (OR, 1.60; 95% CI 1.35–1.90) and lower overall survival (HR, 2.08; 95% CI 1.55–2.80). The sensitivity analysis proved the stability of results in terms of publication years, region, time of diagnosis, sample size, female rate, measurement and follow up period.

Conclusions

Sarcopenia is a robust indicator of mortality in spinal metastasis patients and it might be applied to decision-making tools to assess survival probability and adjust the extent of treatment, while a lack of higher level of evidence is existing.

Systematic Review Registration

PROSPERO CRD42021283348.

CT evaluation for sarcopenia involving the psoas and paravertebral muscles in patients with total hip arthroplasty

BACKGROUND

Computed tomography (CT) has been validated in diagnosing sarcopenia in various clinical conditions.

AIM

To evaluate the core abdominal muscles in terms of sarcopenia in patients with total hip arthroplasty (THA) with and without complication.

METHODS

Retrospective analysis of patients with a pelvic CT revealed 145 consecutive patients with THA. Also, 118 consecutive cases with normal CT scans constituted the control group. The area and density measurements of bilateral psoas (PSA, psoas area; PSD, psoas density) and paravertebral (PVA, paravertebral area; PVD, paravertebral density) muscles were performed at the level of L3 or L4 vertebrae regardless of prosthesis side. All measurements were evaluated in normal cases and in patients with THA, as well as in patients with complicated prostheses.

RESULTS

In the whole population and subgroup of patients with bilateral THA, bilateral PSA, PSD, and PVD but not the PVA were lower in patients with THA compared to controls (all p < 0.01). In patients with unilateral prostheses, ipsilateral PSA, PSD, and bilateral PVD but not the PVA were lower compared to controls (all p < 0.01). Furthermore, in patients with unilateral prostheses with complication, only ipsilateral PSD was lower compared to patients with unilateral prostheses without complication (all p < 0.05) and in patients with bilateral prostheses with complication, bilateral PSA, PSD, and PVD but not the PVA were lower compared to patients with bilateral prostheses without complication (all p < 0.05).

CONCLUSION

Sarcopenia indicated by the area and density measurements of core abdominal muscles can be associated with the presence and complication of hip prostheses.

Skeletal muscle radiodensity and cancer outcomes: A scoping review of the literature

Patients with cancer are more prone to experience myosteatosis than healthy individuals. The aim of this review was to summarize the methodologies applied for low skeletal muscle radiodensity (SMD) assessment in oncology patients, as well as to describe the major findings related to SMD and cancer outcomes. This scoping review included studies that were published until November 2020 in English, Portuguese, or Spanish; were performed in humans diagnosed with cancer, adult and/or elderly, of both sexes; investigated SMD through computed tomography of the region between the third and fifth lumbar vertebrae, considering at least two muscular groups; and evaluated clinical and/or surgical outcomes. Eighty-eight studies met the inclusion criteria (n = 37,583 patients). Survival was the most evaluated outcome. Most studies reported a significant association between low SMD and unfavorable outcomes. However, this relationship was not clear for survival, antineoplastic treatment, and surgical complications, potentially because of the unstandardized approaches for the assessment of SMD and inadequate study design. Future studies should address these issues to provide an in-depth understanding of the clinical relevance of SMD in cancer outcomes as well as how SMD is influenced by individuals and tumor-related characteristics in patients with cancer.

Automatic segmentation of paravertebral muscles in abdominal CT scan by U-Net: The application of data augmentation technique to increase the Jaccard ratio of deep learning

ABSTRACT

Sarcopenia, characterized by a decline of skeletal muscle mass, has emerged as an important prognostic factor for cancer patients. Trunk computed tomography (CT) is a commonly used modality for assessment of cancer disease extent and treatment outcome. CT images can also be used to analyze the skeletal muscle mass filtered by the appropriate range of Hounsfield scale. However, a manual depiction of skeletal muscle in CT scan images for assessing skeletal muscle mass is labor-intensive and unrealistic in clinical practice. In this paper, we propose a novel U-Net based segmentation system for CT scan of paravertebral muscles in the third and fourth lumbar spines. Since the number of training samples is limited (i.e., 1024 CT images only), it is well-known that the performance of the deep learning approach is restricted due to overfitting. A data augmentation strategy to enlarge the diversity of the training set to boost the performance further is employed. On the other hand, we also discuss how the number of features in our U-Net affects the performance of the semantic segmentation. The efficacies of the proposed methodology based on w/ and w/o data augmentation and different feature maps are compared in the experiments. We show that the Jaccard score is approximately 95.0% based on the proposed data augmentation method with only 16 feature maps used in U-Net. The stability and efficiency of the proposed U-Net are verified in the experiments in a cross-validation manner.

Prognostic value of psoas major muscle density in patients with breast cancer metastases to bone: a retrospective single-center cohort study

OBJECTIVE

Although sarcopenia is associated with poor prognosis for cancer patients, the relationship between muscle quantity and quality, and prognosis of breast cancer patients with bone metastases is unclear. This study aims to evaluate the association of muscle parameters, muscle area and density, and overall survival (OS) from the diagnosis of bone metastases in breast cancer patients with bone metastases.

METHODS

This study retrospectively investigated the prognostic value of muscle area and density in 90 women who were diagnosed with breast cancer with bone metastases between September 2005 and June 2018. We measured psoas major muscle and paravertebral muscle area and density on single axial computed tomography images at the L3 level and subgrouped the patients into higher or lower groups for each muscle measurement, using median values as cutoffs. We evaluated associations between OS and muscle parameters, using a Cox proportional hazards model adjusted by age and prognostic score for bone metastases (modified Katagiri score).

RESULTS

Median OS among patients with lower psoas major muscle density (25 months) was significantly shorter than in the higher psoas major muscle density group (61 months; hazard ratio: 1.79, 95% confidence interval: 1.01-3.16, P = 0.045). However, muscle area and paravertebral muscle density were not associated with OS in this setting.

CONCLUSION

Lower psoas major muscle density was a predictor of poor prognosis in patients with breast cancer metastases to bone. The association between psoas major muscle density and prognosis allows wider research into interventions that can prevent loss of muscle density.

Myosteatosis reduces overall survival in patients with digestive system malignancies: a meta-analysis with trial sequential analysis

The impact of myosteatosis on the outcomes of digestive malignancies has gained great attention recently. However, studies on the impact of myosteatosis show inconsistent results. We conducted a meta-analysis to clarify the relationship between myosteatosis and the overall survival of digestive cancer patients. The systematic literature search was conducted on PubMed/MEDLINE, Web of Science, and Embase from inception through March 27, 2021. Meta-analysis was performed using the random-effects model. Out of 3451 studies screened, 47 studies including 21,194 patients passed the screening criteria. The average prevalence of myosteatosis was 46.4%. Patients with myosteatosis had 44% increased mortality risk compared with non-myosteatosis patients (HR: 1.44, 95% CI: 1.33-1.55, P < .05). The predictive value of myosteatosis held regardless of country zone, study design, statistical model, Newcastle-Ottawa Scale (NOS) scores, treatment, sample size, and tumor stage. Nevertheless, the predictive value of myosteatosis was only evident for patients with esophagogastric cancers, cholangiocarcinoma/pancreatic cancers, or colorectal cancers. Overall, the results of this meta-analysis were robust based on sensitivity, subgroup, meta-regression, and trial sequential analyses and suggested that myosteatosis predicted worse overall survival (OS) in digestive malignancies patients.

Muscle-Related Parameters as Determinants of Survival in Patients with Stage I-III Gastric Cancer Undergoing Gastrectomy

Purpose: This study aimed to evaluate the prognostic potential of muscle-related parameters (MRPs) at the level of the third lumbar vertebra (L3) using computerized tomography (CT) images in patients with stage I-III gastric cancer (GC) who underwent curative gastric resection.

Methods: Patients with stage I-III GC who underwent curative gastric resection between October 2006 and June 2014 were enrolled in this study. In addition to demographic and clinical parameters, MRPs, such as skeletal muscle index (SMI), skeletal muscle radiation attenuation (SMRA), paraspinal muscle index (PMI), and paraspinal muscle radiation attenuation (PMRA), at the L3 level using CT images were collected and analyzed. The Kaplan-Meier method was used to estimate survival, and a Cox proportional hazard model was used to calculate the hazard ratio. In addition, the Pearson correlation coefficient was obtained as a measure of the linear relationship between the variables.

Results: Data from 339 patients (233 men and 116 women) were analyzed. A strong correlation between SMI and PMI (r = 0.91); and SMRA and PMRA (r = 0.80) were observed, but only weak correlations between SMI and SMRA; and PMI and PMRA were found. When using the Cox model, SMRA or PMRA was a determinant of survival, but SMI and PMI were not. In the full model formed by adding SMRA or PMRA to a baseline model that included demographic and clinical variables, the C-index increased above 0.8, indicating excellent discrimination for both overall survival (OS) and disease-free survival (DFS). Moreover, the C-index of the model containing PMRA was higher than that of the model containing SMRA. Finally, there was a weak correlation between the prognostic nutritional index and SMRA or PMRA.

Conclusions: With the multivariate Cox model, SMRA and PMRA appeared to determine survival. In addition, adding SMRA or PMRA to the baseline model increased the C-index above 0.8, indicating excellent discrimination for both OS and DFS. Moreover, compared to SMRA, the model containing PMRA appears to be a more accurate model for survival determination.

Association Between the Normal-Density Psoas Muscle Index and Handgrip Strength or Gait Speed in Maintenance Hemodialysis Patients

Introduction: This study aimed to evaluate the association between the psoas muscle (PM) index with or without fatty infiltration and various indices associated with muscle mass in hemodialysis (HD) patients.

Methods: We included stable HD patients (n = 83). The collected data included subjective global assessment (SGA) score, ASM/Ht² (appendicular skeletal muscle mass divided by the squared height in meters), gait speed (GS; m/s), and handgrip strength (HGS; kg). The abdominal computed tomography (CT) image was obtained using a CT scanner. The PM and normal-density PM (NPM) indices (mm²/m²) were calculated using the whole PM area or the area with an attenuation range of 35–100 HU divided by the squared height in meters.

Results: Correlation coefficients for the SGA score, ASM/Ht², HGS, and GS were greater for the NPM index than for the PM index. The linear regression analysis showed that, on multivariate analysis, the NPM index was significantly associated with the SGA score, ASM/Ht², and GS. However, the PM index was significantly associated with the SGA score and ASM/Ht² but not with HGS or GS. For calculating the low GS, the area under the receiver operating characteristic curve area was significantly greater for the NPM index than for the PM index (P = 0.012).

Conclusion: The present study suggested that the NPM index excluding fatty infiltration may be an early and useful indicator for detecting muscle strength and physical performance among HD patients.

Clinical Significance of Paraspinal Muscle Parameters as a prognostic factor for survival in Gastric Cancer Patients who underwent Curative Surgical Resection

Background: The quantitative and qualitative skeletal muscle parameters have been proposed to predict the outcome of patients with gastric cancer. However, the evidence for their association with long-term survival is still conflicting. This study aimed to investigate the effect of paraspinal muscle parameters on overall survival (OS) and disease-free survival (DFS) in patients with gastric cancer who underwent curative resection.

Methods: Patients with stages I or II gastric cancer who underwent curative resection between October 2006 and June 2016 were identified from electrical medical records. Paraspinal muscle area and attenuation were measured at the level of the third lumbar vertebra using computerized tomography images. For the analysis of OS and DFS, proportional hazards model was used, incorporating demographic, pathologic, laboratory, and radiologic variables.

Results: This study enrolled 296 patients (192 men and 104 women). In the multivariate proportional hazards model, total gastrectomy (hazard ratio [HR], 2.65; 95% Confidence interval [CI], 1.36-5.19; p = 0.0044), neutrophil-lymphocyte ratio (NLR) (HR, 1.27; 95% CI, 1.06-1.51; p = 0.0081), serum albumin level (HR, 0.16; 95% CI, 0.07-0.39; p < 0.0001), paraspinal muscle area adjusted for body surface area (PMA_BSA) (HR, 3.06; 95% CI, 1.65-5.67; p = 0.0004), and mean attenuation in paraspinal muscle (PMMA) (HR, 3.38; 95% CI, 1.75-6.53; p = 0.0003) were prognostic factors for OS. Similarly, total gastrectomy (HR, 2.11; 95% CI, 1.10-4.06; p = 0.0243), NLR (HR, 1.25; 95% CI, 1.06-1.48; p = 0.0071), serum albumin level (HR, 0.22; 95% CI, 0.10-0.51; p = 0.0035), PMA_BSA (HR, 2.42; 95% CI, 1.34-4.37; p = 0.0035), and PMMA (HR, 3.19; 95% CI, 1.71-5.93; p = 0.0003) were prognostic factors for DFS.

Conclusions: The pretreatment paraspinal muscle parameters such as PMA_BSA and PMMA along with total gastrectomy, NLR, and serum albumin level could predict OS and DFS in patients with stages I or II gastric cancer who underwent curative surgical resection. Because PMA_BSA and PMMA are newly characterized parameters in gastric cancer, the relationship with the survival of these parameters requires further validation in further studies before they are subjected to clinical applications.

Assessing skeletal muscle radiodensity by computed tomography: An integrative review of the applied methodologies

Low-radiodensity skeletal muscle has been related to the degree of muscle fat infiltration and seems to be associated with worse outcomes. The aim of this study was to summarize the methodologies used to appraise skeletal muscle radiodensity by computed tomography, to describe the terms used in the literature to define muscle radiodensity and to give recommendations for its measurement standardization. An integrative bibliographic review in four databases included studies published until August 2019 in Portuguese, English or Spanish and performed in humans, adults and/or the elderly, of both sex, which investigated skeletal muscle radiodensity through computed tomography (CT) of the region between the third and fifth lumbar vertebrae and evaluated at least two muscular groups. One hundred and seventeen studies were selected. We observed a trend towards selecting all abdominal region muscle. A significant methodological variation in terms of contrast use, selection of skeletal muscle areas, radiodensity ranges delimitation and their cut-off points, as well as the terminologies used, was also found. The methodological differences detected are probably due to the lack of more precise information about the correlation between skeletal muscle radiodensity by CT and its molecular composition, among others. Therefore, until the gaps are addressed in future studies, authors should avoid arbitrary approaches when reporting skeletal muscle radiodensity, especially when it comes to prognosis inference. Studies using both CT and direct methods of muscle composition evaluation are encouraged, to enable the definition and validation of the best approach to classify fat-infiltrated muscle tissue, which will favour the nomenclature uniformization.

Myosteatosis and prognosis in cancer: Systematic review and meta-analysis

BACKGROUND

The evidence that body composition parameters influence multiple cancer outcomes is rapidly expanding. Excess adiposity deposits in muscle tissue, termed myosteatosis, can be detected in CT scans through variations in the density of muscle tissues (Hounsfield Units). Patients with similar muscle mass but different amounts of intramuscular adipose infiltration have increased chemotherapy toxicity, time to tumor progression and other adverse outcomes among different cancer types. Our review examines the impact of myosteatosis on overall survival (OS) in patients with cancer.

METHODS

A systematic search of the literature was conducted on PubMed/ MEDLINE, Cochrane CENTRAL, and EMBASE. Meta-analysis was conducted using a random-effects model. Risk of bias was evaluated using the Newcastle-Ottawa Quality assessment for cohort studies, funnel plot (publication bias), and GRADE summary of findings tool from Cochrane.

RESULTS

A total of 4880 articles were screened from which 40 articles selected, including 21,222 patients. The overall mean proportion of patients with myosteatosis was 48 % (range 11-85 %). Using skeletal muscle density (SMD), patients classified as having myosteatosis had 75 % greater mortality risk compared to non-myosteatosis patients (HR 1.75 95 % CI 1.60-1.92, 40 studies) (p < .00001) (i2 = 62 %). Specifically, myosteatosis was prognostic for worse OS in patients with gynecological, renal, periampullary/pancreatic, hepatocellular, gastroesophageal, and colorectal carcinoma, and lymphomas.

CONCLUSION

Our analysis of the literature shows that cancer patients with myosteatosis have shorter survival. Our findings suggest that in oncological practice, muscle density assessment is valuable as a prognostic parameter.

Muscle mass, assessed at diagnosis by L3-CT scan as a prognostic marker of clinical outcomes in patients with gastric cancer: A systematic review and meta-analysis

BACKGROUND & AIMS

Computed tomographic (CT) imaging at third lumbar vertebra (L3), routinely used by oncologists, represents a reliable tool to quantify muscle mass. A systematic review and meta-analysis was performed to assess the efficacy of CT scan to define muscle mass as a prognostic marker in gastric cancer (GC) patients undergoing gastrectomy and/or chemotherapy. The primary outcomes were overall survival (OS) and recurrence-free survival (RFS) and the secondary outcomes included postoperative length of hospital stay (P-LOS), total and severe complications in GC patients undergoing gastrectomy.

METHODS

Three electronic bibliographic databases - MEDLINE, Web of Science and Cochrane Central Register of Controlled Trials - were used to conduct a systematic literature search based on fixed inclusion and exclusion criteria, until April 2019. The adjusted and unadjusted hazard ratio (HR), odds ratio (OR) and mean difference (MD) with 95% confidence interval (CI) were used to analyse the dichotomous variables (OS, RFS, total and severe complications) and continuous variables (P-LOS). Random- and fixed effects models were used according to the heterogeneity.

RESULTS

A total of 5610 GC patients from 20 studies were identified. Low muscle mass at diagnosis was found in 32.7% of GC patients and was significantly associated with poorer OS (HR 2.02, 95% CI 1.71-2.38, p < 0.00001, I² = 47%) and worse RFS (HR 1.97, 95% CI 1.71-2.26, p < 0.00001, I² = 0%). Meta-analysis of adjusted HR from multivariable analyses confirmed the association between OS and low muscle mass (HR 1.89, 95% CI 1.68-2.12, p < 0.00001, I² = 36%). Furthermore, low muscle mass and poorer OS were significantly associated in metastatic GC patients exclusively undergoing chemotherapy (HR 1.61, 95% CI 1.23-2.11, p < 0.0006, I² = 18%). Moreover, preoperative low muscle mass was significantly associated with longer P-LOS (MD 1.19, 95% CI 0.68-1.71, p < 0.00001, I² = 0%), higher risk of postoperative complications (OR 1.76, 95% CI 1.17-2.66, p = 0.007, I² = 77%) and severe complications (OR 1.54, 95% CI 1.03-2.29, p = 0.04, I² = 49%) in GC patients undergoing gastrectomy.

CONCLUSIONS

Low muscle mass, assessed by L3 CT-scan, affects almost 1/3 of GC patients at diagnosis and acts as a negative prognostic marker on many clinical outcomes. Therefore, identifying GC patients with low muscle mass at diagnosis or at follow-up visit should be recommendable. Clinical nutritionists should be part of tumor boards meetings to screen low muscle mass in order to prompt personalized nutritional support.

Computed tomography-based psoas skeletal muscle area and radiodensity are poor sentinels for whole L3 skeletal muscle values

Background and aims

Computed tomography (CT)-based measurement of skeletal muscle cross-sectional area (CSA) and Hounsfield unit (HU) radiodensity are used to assess the presence of sarcopenia and myosteatosis, respectively. The validated CT-based technique involves analysis of skeletal muscle at the third lumbar vertebral (L3) level. Recently there has been increasing interest in the use of psoas muscle alone as a sentinel. However, this technique has not been extensively investigated or compared with the previous validated standard approach.

Methods

Portovenous phase CT images at the L3 level were identified retrospectively from a single institution in 150 patients who had non-emergency scans and were analysed by a single assessor using SliceOmatic software v5.0 (TomoVision, Canada). Manual segmentation based upon validated HU thresholds for skeletal muscle density was performed for all skeletal muscle, as well as the individual muscle groups. The muscle CSA and mean radiodensity of each group were compared against the whole L3 slice values.

Results

When compared with whole L3 slice CSA, anterior abdominal wall CSA had the strongest correlation (r = 0.9315, p < 0.0001) followed by paravertebral (r = 0.8948, p < 0.0001), then psoas muscle (r = 0.7041, p < 0.0001). The mean ± SD density of the psoas muscle (42 ± 8.4 HU) was significantly higher than the whole slice radiodensity (32.3 ± 9.5 HU, p < 0.0001), with paravertebral radiodensity being a more accurate estimation (34.5 ± 10.8 HU). There was a significant difference in the prevalence of myosteatosis when the density measured from the psoas was compared with that of the whole L3 skeletal muscle (27.7% vs. 66.0%, p < 0.0001).

Conclusion

Whole L3 slice CSA correlated positively with psoas muscle CSA but was subject to wide variability in results. Psoas muscle radiodensity was significantly greater than whole L3 slice density and resulted in underestimation of the prevalence of myosteatosis. Given the lack of equivalence from individual muscle groups, we recommend that further work be undertaken to investigate which muscle group, or indeed whether the gold standard of whole L3 skeletal muscle, provides the best correlation with clinical outcomes.