Skeletal muscle and related protein expression as prognostic factors in thymic squamous cell carcinoma

Background

Sarcopenia and its marker, the psoas muscle index (PMI), have attracted attention as prognostic factors for various types of cancers. The fragile X-related 1 (FXR1) gene is highly expressed in myocytes, and FXR1 overexpression is a candidate biomarker for poor survival in several types of cancers. Thymic squamous cell carcinoma (TSQCC) is rare, and no studies assessing its prognostic factors, particularly in terms of skeletal muscle mass and FXR1 expression, are available.

Methods

We retrospectively investigated the prognostic significance of PMI in 34 patients who underwent TSQCC resection, considering the status of FXR1 and tumor programmed death-ligand 1 (PD-L1). PMI was calculated from the bilateral psoas muscle using preoperative computed tomography (CT). Patients were divided into two groups: low PMI (<58.2%, n=17) and normal PMI (≥58.2%, n=17). Immunohistochemical analysis was performed to determine the FXR1 and PD-L1 expression levels.

Results

Low PMI was significantly associated with worse overall survival (OS) (5-year survival rate; 86% vs. 100%; P=0.026) and marginally associated with worse disease-free survival (DFS) (5-year survival rate; 39% vs. 66%; P=0.090) compared with normal PMI. The immunohistochemical analysis revealed that the FXR1 intensity score (0-1+: 6% vs. 0%; 2+-3+: 94% vs. 100%; P=0.31), median FXR1 distribution (95% vs. 90%; P=0.63), and PD-L1 status (high: 47% vs. 59%; P=0.49) were not significantly different between the two groups.

Conclusions

Our findings suggest that PMI might be considered as a potential prognostic factor in TSQCC and that FXR1 is widely expressed regardless of the PMI status. Skeletal muscle mass may play a role in the prognosis of TSQCC.

Sarcopenia defined by psoas muscle index independently predicts long-term survival after living donor liver transplantation in male recipients

Background

The effect of sarcopenia on long-term outcomes in recipients after living donor liver transplantation (LDLT), including overall survival and hepatocellular carcinoma (HCC) recurrence, remains unclear, especially in China.

Methods

From 2009 to 2015, 117 adult patients underwent LDLT in our center. In all, 82 patients who had computed tomography images reaching the third lumbar vertebra level within 1 month of LDLT were included; 70 male patients were included in the final analysis after excluding 12 female patients because of poor performance of the calculated cutoff value. Sarcopenia was defined according to the psoas muscle index (PMI) cutoff value, which was calculated based on dynamic time-dependent outcomes using X-tile software. Cox proportional hazards models were used to assess multivariate-adjusted hazards ratios (HRs) to seek potential correlations between sarcopenia and posttransplant outcomes.

Results

According to the cutoff value of PMI (6.25 cm²/m²), 38 patients (54.3%) were diagnosed with sarcopenia. After an average of 63.3 months of follow-up, 21 patients died after LDLT, 16 in the sarcopenia group and 5 in the non-sarcopenia group, respectively. Sarcopenia was identified as being significantly associated with worse posttransplant overall survival in multivariate analysis, resulting in an HR of 3.22 [95% confidence interval (CI), 1.15-8.98]. Among the 50 recipients with HCC, sarcopenia was significantly associated with HCC recurrence in univariate analysis (HR 2.87, 95% CI, 1.06-7.80) but was not detected as an independent risk factor of HCC recurrence in multivariate analysis, although a trend (tendency)towards significance was observed (HR 2.60, 95% CI, 0.95-7.10; P=0.062).

Conclusions

Sarcopenia defined by PMI is a feasible and reliable independent predictor of posttransplant overall survival in male LDLT candidates. However, its correlation with posttransplant HCC recurrence remains uncertain.

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.

Impact of sarcopenic overweight on the outcomes after living donor liver transplantation

Background

The effect of body composition disturbances has been recently in focus. Sarcopenic obesity, a co-occurrence of low muscle mass and high body fat was reportedly predictive of high mortality in patients with cirrhosis. However, the impact of the interacting sarcopenia and overweight on the outcomes after liver transplantation is still unclear.

Methods

We evaluated 200 patients undergoing adult-to-adult living donor liver transplantation at our institution between January 2008 and November 2013 classified according to BMI and psoas muscle index (PMI) on admission to transplant into 4 subgroups; sarcopenic overweight (SO), sarcopenic non-overweight (SN), non-sarcopenic overweight and non-sarcopenic non-overweight (NN). Short-term outcomes and overall post-transplant survival were compared among the four subgroups.

Results

Sarcopenic patients with preoperative low PMI had higher incidence of postoperative bacteremia and major postoperative complications, and poorer overall post-transplant survival than non-sarcopenic patients with normal/high PMI (P<0.001, respectively). Overweight recipients had a significantly higher overall survival (OS) rate than non-overweight patients (P=0.021). SO subgroup (low PMI and BMI ≥25) had statistically indifferent incidence of postoperative bacteremia, major postoperative complications or overall post-transplant survival than other recipients. In contrast, SN subgroup (low PMI and BMI <25) had higher incidence of postoperative bacteremia (P<0.001), major postoperative complications (P<0.001) than the SO subgroup and possessed the poorest OS among the four recipient subgroups (P=0.001).

Conclusions

In living donor liver transplantation, preoperative SO did not confer added significant morbidity or mortality risks than the stand-alone sarcopenia.