Do psoas muscle area and volume correlate with postoperative complications in patients undergoing rectal cancer resection? Am J Surg. 2018;215:503-506. [PMID: 29277239 DOI: 10.1016/j.amjsurg.2017.10.052]

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.

Preoperative Body Composition Combined with Tumor Metabolism Analysis by PET/CT Is Associated with Disease-Free Survival in Patients with NSCLC

Objective. To evaluate the relationship between preoperative primary tumor metabolism and body composition in patients with NSCLC and analyze their effects on DFS. Method. A retrospective study was conducted on 154 patients with NSCLC. All patients were scanned by baseline 18F-FDG PET/CT. SUVmax (maximum standard uptake value) of primary tumor, liver SUVmean (mean standard uptake value), and spleen SUVmean were measured by AW workstation. The skeletal muscle area (SMA), skeletal muscle mass index (SMI), skeletal muscle radiation density (SMD), visceral fat area (VFA), visceral adipose tissue index (VATI), and skeletal muscle visceral fat ratio (SVR) were measured by ImageJ software. Kaplan–Meier survival analysis was used to evaluate the impact of the above parameters on DFS. Results. Compared with the low SUVmax group of primary tumors, the mean values of SMA, VFA, and VATI in the high SUVmax group were significantly higher. In addition, there were obvious differences in histopathological type, pathological differentiation, AJCC stage, and T stage between the two groups. Univariate analysis of DFS showed that VFA, VATI, pathological differentiation, tumor SUVmax, AJCC stage, tumor T stage, and N stage all affected the DFS of patients except for the parameters reflecting skeletal muscle content. Multivariate regression analysis showed that only VFA and SUVmax were associated with DFS. Kaplan–Meier survival analysis showed that high SUVmax, low VFA, high T stage, and high N stage were related to the decrease of DFS. Conclusion：Preoperative 18F-FDG PET/CT could comprehensively evaluate the primary tumor SUVmax, skeletal muscle, and visceral fat in patients with NSCLC. The combination of primary tumor SUVmax and visceral fat area can well evaluate the prognosis of patients with NSCLC.

MRI biomarker of muscle composition is associated with severity of pelvic organ prolapse

BACKGROUND

The pathophysiology of pelvic organ prolapse is largely unknown. We hypothesized that reduced muscle mass on magnetic resonance defecography (MRD) is associated with increased pelvic floor laxity. The aim of this study was to compare the psoas and puborectalis muscle mass composition and cross-sectional area among patients with or without pelvic laxity.

METHODS

An observational retrospective study was conducted on women > age 18 years old who had undergone MRD for pelvic floor complaints from January 2020 to December 2020 at Stanford Pelvic Health Center. Pelvic floor laxity, pelvic organ descent, and rectal prolapse were characterized by standard measurements on MRD and compared to the psoas (L4 level) and puborectalis muscle index (cross-sectional area adjusted by height) and relative fat fraction, quantified by utilizing a 2-point Dixon technique. Regression analysis was used to quantify the association between muscle characteristics and pelvic organ measurements.

RESULTS

The psoas fat fraction was significantly elevated in patients with abnormally increased resting and strain H and M lines (p < 0.05) and increased with rising grades of Oxford rectal prolapse (p = 0.0001), uterovaginal descent (p = 0.001) and bladder descent (p = 0.0005). In multivariate regression analysis, adjusted for age and body mass index, the psoas fat fraction (not muscle index) was an independent risk factor for abnormal strain H and M line; odds ratio (95% confidence interval) of 17.8 (2-155.4) and 18.5 (1.3-258.3) respectively, and rising Oxford grade of rectal prolapse 153.9 (4.4-5383) and bladder descent 12.4 (1.5-106). Puborectalis fat fraction was increased by rising grades of Oxford rectal prolapse (p = 0.0002).

CONCLUSIONS

Severity of pelvic organ prolapse appears to be associated with increasing psoas muscle fat fraction, a biomarker for reduced skeletal muscle mass. Future prospective research is needed to determine if sarcopenia may predict postsurgical outcomes after pelvic organ prolapse repair.

Clinical Relevance of Myopenia and Myosteatosis in Colorectal Cancer

Sarcopenia was initially described as a decrease in muscle mass associated with aging and subsequently also as a consequence of underlying disease, including advanced malignancy. Accumulating evidence shows that sarcopenia has clinically significant effects in patients with malignancy, including an increased risk of adverse events associated with medical treatment, postoperative complications, and a poor survival outcome. Colorectal cancer (CRC) is one of the most common cancers worldwide, and several lines of evidence suggest that preoperative sarcopenia negatively impacts various outcomes in patients with CRC. In this review, we summarize the current evidence in this field and the clinical relevance of sarcopenia in patients with CRC from three standpoints, namely, the adverse effects of medical treatment, postoperative infectious complications, and oncological outcomes.

Effects of psoas major muscle volume in predicting the prognosis of patients with upper urinary tract urothelial carcinoma treated with radical nephroureterectomy

BACKGROUND

This study evaluated the impact of sarcopenia and psoas major muscle volume on the survival of patients with upper urinary tract urothelial carcinoma who had undergone radical nephroureterectomy.

METHODS

We reviewed data from 110 patients treated with radical nephroureterectomy in our department between June 2007 and February 2017. Psoas major muscle volume was quantified based on computed tomography data using Synapse Vincent software. The psoas major muscle volume index was calculated as psoas major muscle volume/height squared (cm3/m2). We analysed relapse-free survival, cancer-specific survival and overall survival after radical nephroureterectomy to identify factors that predicted patient survival.

RESULTS

The median psoas major muscle volume index was 121.5 cm3/m2, and the psoas major muscle volume index was <100 cm3/m2 in 34 of 110 patients (30.9%). Multivariate analysis indicated that ≥pT3-stage cancer, lymphovascular invasion and a psoas major muscle volume index of <100 cm3/m2 were independent predictors of shorter relapse-free survival, cancer-specific survival and overall survival. Using these factors, patients were stratified into three groups: low, intermediate and high risks for relapse-free survival, cancer-specific survival and overall survival.

CONCLUSIONS

Low psoas major muscle volume resulting from sarcopenia, high T stage and the presence of lymphovascular invasion was associated with poor survival in patients with urinary tract urothelial carcinoma who had undergone radical nephroureterectomy, supporting the use of psoas major muscle volume as a new objective prognostic marker.

CT assessment of preoperative nutritional status in gastric cancer: severe low skeletal muscle mass and obesity-related low skeletal muscle mass are unfavorable factors of postoperative complications

BACKGROUND

Computed tomography (CT) has become an important technique for assessing skeletal muscle mass. Low skeletal muscle mass (LSMM) is considered an unfavorable factor for postoperative complications in patients with gastric cancer (GC).

METHODS

Patients who underwent laparoscopic gastrectomy for GC were included. Skeletal muscle mass at the third lumbar vertebra (L3) level was measured by preoperatively using CT. The patients were divided into an LSMM group and a non-LSMM group and the intergroup differences were analyzed. Furthermore, we divided the LSMM group into mild and severe LSMM subgroups. The study also analyzed the influence of obesity-related LSMM on postoperative complications.

RESULTS

A total of 409 patients were enrolled; of them, 265 had LSMM and 41 had severe LSMM. LSMM was associated with age, body mass index, and Nutritional Risk Screening 2002 score. In the multivariate analysis, LSMM was not related to postoperative complications. Further analysis revealed that severe LSMM was a risk factor for postoperative complications. The study also found that the risk of postoperative complications was significantly increased in patients with obesity-related LSMM.

CONCLUSIONS

LSMM was not significantly correlated with postoperative complications. Severe LSMM and obesity-related LSMM are unfavorable factors for postoperative complications with GC after gastrectomy.

Is sarcopenia really a risk factor in the development of postoperative complications?

PURPOSE

This study was aimed to evaluate the impact of sarcopenia, which was defined by total psoas area (TPA) and total psoas volume (TPV) measurements, on the development of major postoperative complications.

MATERIAL-METHODS

Sarcopenia was assessed in 225 patients with gastrointestinal cancer who underwent surgery between October 2015 and March 2020. The impact of sarcopenia defined by TPA and TPV on major postoperative complications was assessed using multivariate analysis.

RESULTS

Both the median TPA and TPV were higher in men than that in women (p < 0.001). The cut-off value of TPA to define sarcopenia was 526.5 mm²/m² and 495.68 mm²/m² for men and women, respectively, and the cut-off value of TPV was 79.6 cm³/m² for men and 83.1 cm³/m² for women, While 102 patients (45.3%) had sarcopenia defined by TPA, 54 (24%) had sarcopenia defined by TPV. Seventy-eight patients had at least one complication; 36 (46%) had major complications, and 15 patients died during the study. In logistic regression analysis, only sex was found as a risk factor for the development of sarcopenia (OR = 13.403, p = 0.014). There was a positive correlation between TPA and TPV in male and female patients separately (r = 0.841 and r = 0.883, respectively, p < 0.001). Only sarcopenia defined by TPV was found as a risk factor for the development of major postoperative complication (OR: 35.349, p = 0.028).

CONCLUSION

Sarcopenia defined by TPV is an independent risk factor in predicting major postoperative complications, not TPA. We believe that volume measurement instead of area is a more accurate method for evaluating sarcopenia in gastrointestinal cancer surgery.

Impacts of Preoperative Psoas Muscle Mass and Visceral Fat Area on Postoperative Short- and Long-Term Outcomes in Patients with Gastric Cancer

BACKGROUND

Sarcopenia and obesity are associated with outcomes after surgery. However, few studies have investigated which more accurately predicts postoperative complications or prognosis in patients with gastric cancer.

METHODS

A total of 567 consecutive patients with gastric cancer who underwent gastrectomy between 2010 and 2015 were retrospectively reviewed. Psoas muscle mass index (PMI) and visceral fat area (VFA) were measured by CT scan. Patients were divided into two groups based on PMI (PMI-H group: male ≥ 6.36 cm²/m², female ≥ 3.92 cm²/m²; and PMI-L group: male < 6.36 cm²/m², female < 3.92 cm²/m²) and two groups based on VFA (VFA-H group: ≥ 100 cm²; VFA-L group: < 100 cm²). The incidence of postoperative complications and the recurrence-free survival (RFS) were compared between the two groups.

RESULTS

The incidence of postoperative complications was significantly higher in the VFA-H group than in the VFA-L group (35.1% vs. 20.3%; P < 0.001), whereas there was no significant difference between the PMI-H and PMI-L groups. Multivariate analysis showed that PMI-L and VFA-H were independent risk factors for pneumonia (odds ratio, 4.49; P = 0.018) and intra-abdominal abscess (odds ratio, 5.19; P = 0.004), respectively. While there was no significant difference in RFS between the VFA-H and VFA-L groups, the PMI-L group showed significantly worse RFS than the PMI-H group (P < 0.001).

CONCLUSIONS

PMI and VFA were useful predictive factors for postoperative pneumonia and intra-abdominal abscess, respectively. PMI might be a useful prognostic factor in patients with gastric cancer, but VFA is not.

Are computed tomography-based measures of specific abdominal muscle groups predictive of adverse outcomes in older cancer patients?

PURPOSE

It is unknown whether computed tomography (CT)-based total abdominal muscle measures are representative of specific abdominal muscle groups and whether analysis of specific abdominal muscle groups are predictive of the risk of adverse outcomes in older cancer patients.

METHODS

Retrospective single-center cohort study in elective colon cancer patients aged ≥65 years. CT-based skeletal muscle (SM) surface area, muscle density and intermuscular adipose tissue (IMAT) surface area were determined for rectus abdominis; external- and internal oblique and transversus abdominis (lateral muscles); psoas; and erector spinae and quadratus lumborum (back muscles). Outcomes were defined as severe postoperative complications (Clavien-Dindo score >2) and long-term survival (median follow-up 5.2 years).

RESULTS

254 older colon cancer patients were included (median 73.6 years, 62.2% males). Rectus abdominis showed the lowest SM surface area and muscle density and the back muscles showed the highest IMAT surface area. Psoas muscle density, and lateral muscle density and percentage IMAT were associated with severe postoperative complications independent of gender, age and cancer stage.

CONCLUSIONS

CT-based total abdominal muscle quantity and quality do not represent the heterogeneity that exists between specific muscle groups. The potential added value of analysis of specific muscle groups in predicting adverse outcomes in older (colon) cancer patients should be further addressed in prospective studies.

Cancer cachexia and treatment toxicity

PURPOSE OF REVIEW

Cancer cachexia is a metabolic disturbance resulting in a loss of skeletal muscle mass that is generally not reversed through traditional nutritional interventions. We review on both the impact of nutritional status on cancer treatment side effects, as well as cancer- specific outcomes.

RECENT FINDINGS

Cancer-specific cachexia and sarcopenia are associated with increased treatment-associated toxicity, and overall worse cancer-specific outcomes across all cancer types in surgical, chemotherapeutic, and radiotherapeutic populations. Despite the fact that cancer cachexia is generally thought to be irreversible, there is some evidence that nutritional intervention can be helpful.

SUMMARY

Nutritional status is an important factor to consider in determining cancer therapy. Patients with poor nutritional status should be identified prior to the initiation of therapy and be monitored judiciously.

Clinical impact of psoas muscle volume on the development of inguinal hernia after robot-assisted radical prostatectomy

BACKGROUND

Sarcopenia, a syndrome characterized by the loss of skeletal muscle mass, has attracted attention in the field of oncology, as it reflects poor nutritional status. The present study aimed to determine the risk factors for postoperative inguinal hernia (PIH) development after robot-assisted laparoscopic radical prostatectomy (RARP) for prostate cancer, and discuss whether sarcopenia could be used as a sensitive predictor of PIH.

METHODS

We reviewed the medical records of 147 patients who underwent RARP at our institution. The psoas muscle volume (PMV), as an indicator of sarcopenia, was quantified from computed tomography images using a 3-dimensional image analysis system. Multivariate cox regression analyses were performed to identify independent predictors of PIH, including pre- and peri-operative factors.

RESULTS

The mean PMV was 393 cm³, and the correlation coefficient between PMV and body mass index was 0.37 (p < 0.01). The PIH-free rate at 2 years postoperatively was 78.2% among all patients. The multivariate analysis revealed that a PMV < 350 cm³ was a significant risk factor for PIH (p = 0.03; hazard ratio 2.19). Body mass index, age, prostate volume, lymph node dissection, nerve sparing, rectus muscle thickness, and console time were not related to PIH development. The PIH-free rate at 2 years postoperatively was 83.4% and 68.9% in patients with a PMV ≥ 350 cm³ and < 350 cm³, respectively (p < 0.05).

CONCLUSIONS

PIH occurred significantly more frequently in patients with a PMV < 350 cm³ than in patients with a PMV ≥ 350 cm³, and a low PMV was an independent risk factor for PIH. Thus, urologists should pay attention to the cumulative incidence of IH after RARP, especially in patients with a PMV < 350 cm³.

Risk of Psoas Muscle Atrophy After Endovascular Aneurysm Repair Assessed by Cross-Sectional Psoas Muscle Area

PURPOSE

We evaluated possible association of decreased psoas muscle area (PMA) after endovascular aneurysm repair (EVAR) by measuring the area of muscle in computed tomographic (CT) images.

MATERIALS AND METHODS

We retrospectively reviewed CT images of 201 consecutive patients who underwent EVAR at our institution between April 1, 2015, and November 9, 2018, and compared them with images of 75 consecutive patients with no history of EVAR, who served as controls and underwent thoracic endovascular aortic repair (TEVAR) during the same period. We investigated EVAR and possible associated factors that might be potential predictors of decrease in PMA.

RESULTS

Those patients with a history of EVAR demonstrated significantly greater mean decrease in PMA than those with a history of TEVAR after the repair procedure (mean 6.25% (8.5); P < 0.001; odds ratio [OR], 3.63; 95% confidence interval [CI] 1.90-6.90).

CONCLUSION

Although EVAR is a less stressful procedure than other major abdominal surgeries, we identified it as an independent predictor of decreased area of the psoas muscle. Thus, our results might encourage post-procedural evaluation of frailty associated with psoas muscle function and prescription of appropriate rehabilitation interventions after EVAR to help prevent deterioration of patients' abilities.

The Role of CT-Quantified Body Composition on Longitudinal Health-Related Quality of Life in Colorectal Cancer Patients: The Colocare Study

BACKGROUND

Obesity, defined by body mass index (BMI), measured at colorectal cancer (CRC) diagnosis has been associated with postoperative complications and survival outcomes. However, BMI does not allow for a differentiation between fat and muscle mass. Computed tomography (CT)-defined body composition more accurately reflects different types of tissue and their associations with health-related quality of life (HRQoL) during the first year of disease, but this has not been investigated yet. We studied the role of visceral and subcutaneous fat area (VFA and SFA) and skeletal muscle mass (SMM) on longitudinally assessed HRQoL in CRC patients.

METHODS

A total of 138 newly diagnosed CRC patients underwent CT scans at diagnosis and completed questionnaires prior to and six and twelve months post-surgery. We investigated the associations of VFA, SFA, and SMM with HRQoL at multiple time points.

RESULTS

A higher VFA was associated with increased pain six and twelve months post-surgery (β = 0.06, p = 0.04 and β = 0.07, p = 0.01) and with worse social functioning six months post-surgery (β = -0.08, p = 0.01). Higher SMM was associated with increased pain twelve months post-surgery (β = 1.03, p < 0.01).

CONCLUSIONS

CT-quantified body composition is associated with HRQoL scales post-surgery. Intervention strategies targeting a reduction in VFA and maintaining SMM might improve HRQoL in CRC patients during the first year post-surgery.

Sarcopenia in patients with colorectal cancer: A comprehensive review

Colorectal cancer (CRC) is the third most commonly diagnosed cancer globally and the second cancer in terms of mortality. The prevalence of sarcopenia in patients with CRC ranges between 12%-60%. Sarcopenia comes from the Greek "sarx" for flesh, and "penia" for loss. Sarcopenia is considered a phenomenon of the aging process and precedes the onset of frailty (primary sarcopenia), but sarcopenia may also result from pathogenic mechanisms and that disorder is termed secondary sarcopenia. Sarcopenia diagnosis is confirmed by the presence of low muscle quantity or quality. Three parameters need to be measured: muscle strength, muscle quantity and physical performance. The standard method to evaluate muscle mass is by analyzing the tomographic total cross-sectional area of all muscle groups at the level of lumbar 3rd vertebra. Sarcopenia may negatively impact on the postoperative outcomes of patients with colorectal cancer undergoing surgical resection. It has been described an association between sarcopenia and numerous poor short-term CRC outcomes like increased perioperative mortality, postoperative sepsis, prolonged length of stay, increased cost of care and physical disability. Sarcopenia may also negatively impact on overall survival, disease-free survival, recurrence-free survival, and cancer-specific survival in patients with non-metastatic and metastatic colorectal cancer. Furthermore, patients with sarcopenia seem prone to toxic effects during chemotherapy, requiring dose deescalations or treatment delays, which seems to reduce treatment efficacy. A multimodal approach including nutritional support (dietary intake, high energy, high protein, and omega-3 fatty acids), exercise programs and anabolic-orexigenic agents (ghrelin, anamorelin), could contribute to muscle mass preservation. Addition of sarcopenia screening to the established clinical-pathological scores for patients undergoing oncological treatment (chemotherapy, radiotherapy or surgery) seems to be the next step for the best of care of CRC patients.

Sarcopenia is associated with worse overall survival in patients with anal squamous cell cancer

BACKGROUND AND OBJECTIVES

Sarcopenia is associated with poor long-term outcomes in many gastrointestinal cancers, but its role in anal squamous cell carcinoma (ASCC) is not defined. We hypothesized that patients with sarcopenic ASCC experience worse long-term outcomes.

METHODS

A retrospective review of patients with ASCC treated at an academic medical center from 2006 to 2017 was performed. Of 104 patients with ASCC, 64 underwent PET/computed tomography before chemoradiation and were included in the analysis. The skeletal muscle index was calculated as total L3 skeletal muscle divided by height squared. Sarcopenia thresholds were 52.4 cm² /m² for men and 38.5 cm² /m² for women. Cox regression analysis was performed to assess overall and progression-free survival.

RESULTS

Twenty-five percent of the patients were sarcopenic (n = 16). Demographics were similar between groups. There was no difference in the clinical stage or comorbidities between groups. On multivariate analysis, factors associated with worse overall survival were male gender (hazard ratio [HR] 3.7, P = .022) and sarcopenia (HR 3.6, P = .019). Male gender was associated with worse progression-free survival (HR 2.6, P = .016).

CONCLUSIONS

Sarcopenia is associated with worse overall survival in patients with anal cancer. Further studies are indicated to determine if survival can be improved with increased attention to nutritional status in sarcopenic patients.

The association between neck adiposity and long-term outcome

Anthropometric indices of obesity (e.g. body mass index, waist circumference and neck circumference) are associated with poor long-term cardiovascular outcome. Prior studies have associated neck circumference and central body adiposity. We explored the association between neck fat volume (NFV) and long-term cardiovascular outcome. The study provides a retrospective analysis of all patients undergoing computerized tomography angiography for suspected cerebrovascular accident between January and December 2013. NFV was assessed by three dimensional reconstructions and was adjusted to height to account for differences in body sizes, thus yielding the NFV/height ratio (NHR). Univariate and multivariate analysis were utilized to explore the association between various indices including NHR and all-cause mortality. The analysis included 302 patients. The average age was 61.9±14.3 years, 60.6% of male gender. Diabetes mellitus, hypertension and cardiovascular disease were frequent in 31.5%, 69.9%, and 72.2% of patients, respectively. The median NHR was 492.53cm² [IQR 393.93–607.82]. Median follow up time was 41.2 months, during which 40 patients (13.2%) died. Multivariate analysis adjusting for age, sex, and diabetes mellitus indicated an independent association between the upper quartile of NHR and all-cause mortality (hazard ratio = 2.279; 95% CI = 1.209–4.299; p = .011). NHR is a readily available anthropometric index which significantly correlated with poor long-term outcome. Following validation in larger scale studies, this index may serve a risk stratifying tool for cardiovascular disease and future outcome.

Prognostic significance of sarcopenia and skeletal muscle mass change during preoperative chemoradiotherapy in locally advanced rectal cancer

BACKGROUND

The aim of this study was to investigate the prognostic impact of sarcopenia and skeletal muscle change in rectal cancer patients who underwent preoperative chemoradiotherapy (preop-CRT).

MATERIAL AND METHODS

From April 2004 to June 2013, we identified non-metastatic rectal cancer patients who underwent preop-CRT. Sarcopenia was evaluated according to previous cut-off value by computed tomography measured before starting preop-CRT (sarcopenia_pre) and 4-6 weeks after cessation of preop-CRT (sarcopenia_post). The severe muscle loss was defined as change in muscle mass < -4.2%/100 days. The hazard ratio (HR) and 95% confidence interval (CI) of sarcopenia and muscle change were estimated using a Cox proportional hazards model adjusted for potential confounders.

RESULTS

Among 93 patients who underwent both pre and post-CRT CTs, 48 (51.6%) and 51 (54.8%) were identified as sarcopenia_pre and sarcopenia_post respectively. Twenty-three patients (24.7%) were included in the severe muscle loss group. Multivariable analysis identified sarcopenia_post (HR 2.6, 95% CI 1-6.2, p = 0.023), and severe muscle loss (HR 2.8, 95% CI 1.2-6.2, p = 0.011) along with age and ypStage as independent risk factors for overall survival. Clinical T4 stage was the only factor that can predict severe muscle loss (OR 3.4, 95% CI 1.2-9.4, p = 0.016).

CONCLUSIONS

Sarcopenia identified after the completion of preop-CRT and change in muscle mass < -4.2%/100 days during preop-CRT are promising parameters to predict overall survival in patents with locally advanced rectal cancer and should be investigated more rigorously.

Assessment of Computed Tomography (CT)-Defined Muscle and Adipose Tissue Features in Relation to Short-Term Outcomes After Elective Surgery for Colorectal Cancer: A Multicenter Approach

BACKGROUND

Sarcopenia, visceral obesity (VO), and reduced muscle radiodensity (myosteatosis) are suggested risk factors for postoperative morbidity in colorectal cancer (CRC), but usually are not concurrently assessed. Published thresholds used to define these features are not CRC-specific and are defined in relation to mortality, not postoperative outcomes. This study aimed to evaluate body composition in relation to length of hospital stay (LOS) and postoperative outcomes.

METHODS

Pre-surgical computed tomography (CT) images were assessed for total area and radiodensity of skeletal muscle and visceral adipose tissue in a pooled Canadian and UK cohort (n = 2100). Sex- and age-specific values for these features were calculated. For 1139 of 2100 patients, LOS data were available, and sex- and age-specific thresholds for sarcopenia, myosteatosis, and VO were defined on the basis of LOS. Association of CT-defined features with LOS and readmissions was explored using negative binomial and logistic regression models, respectively.

RESULTS

In the multivariable analysis, the predictors of LOS (P < 0.001) were age, surgical approach, major complications (incidence rate ratio [IRR] 2.42; 95% confidence interval [CI] 2.18-2.68), study cohort, and three body composition profiles characterized by myosteatosis combined with either sarcopenia (IRR, 1.27; 95% CI 1.12-1.43) or VO (IRR, 1.25; 95% CI 1.10-1.42), and myosteatosis combined with both sarcopenia and VO (IRR, 1.58; 95% CI 1.29-1.93). In the multivariable analysis, risk of readmission was associated with VO alone (odds ratio [OR] 2.66; 95% CI 1.18-6.00); P = 0.018), VO combined with myosteatosis (OR, 2.72; 95% CI 1.36-5.46; P = 0.005), or VO combined with myosteatosis and sarcopenia (OR, 2.98; 95% CI 1.06-5.46; P = 0.038). Importantly, the effect of body composition profiles on LOS and readmission was independent of major complications.

CONCLUSION

The findings showed that CT-defined multidimensional body habitus is independently associated with LOS and hospital readmission.