Sarcopenia is more than simply documenting low skeletal muscle mass

Patients triaged to neoadjuvant chemotherapy have higher rates of sarcopenia: An opportunity for prehabilitation

OBJECTIVE

To compare baseline body composition measures (BCM), including sarcopenia, between patients with advanced epithelial ovarian cancer (EOC) undergoing primary cytoreductive surgery (PCS) versus neoadjuvant chemotherapy/interval cytoreductive surgery (NACT/ICS) and evaluate changes in BCM pre-NACT versus pre-ICS.

METHODS

Patients with stage IIIC/IV EOC who underwent PCS or NACT with curative intent between 1/1/2012 and 7/31/2016 were included. Computed tomography scans were evaluated via a semi-automated program to determine BCM. Measures evaluated include skeletal muscle area (SMA), skeletal muscle density (SMD), skeletal muscle index (SMI), and skeletal muscle gauge (SMG). Sarcopenia was defined as SMI <39.0 cm²/m².

RESULTS

The study included 200 PCS patients and 85 NACT/ICS patients, of which 76 had both pre-NACT and pre-ICS scans. NACT patients were significantly more likely to be sarcopenic compared to PCS patients (40.0% vs 27.5%, p = 0.04). Mean SMA (107.3 vs 113.4 cm², p = 0.004) and mean SMG (1344.6 vs. 1456.9 (cm² x HU)/m², p = 0.06) were lower in NACT patients. Among NACT/ICS patients, mean SMI significantly decreased -1.4 cm²/m² (p = 0.005) at the time of surgery, resulting in a non-statistically significant increase in the percentage of sarcopenic patients from baseline (40.8% vs. 50.0%, p = 0.09).

CONCLUSIONS

Sarcopenia is more common in patients with advanced EOC undergoing NACT compared to PCS when using an evidence-based triage system for triage decisions. Body composition changes significantly over the course of NACT. Sarcopenia may be an indicator of debility and another factor for consideration in treatment planning. Further research into body composition's effects on prognosis and altering sarcopenia is necessary.

Sarcopenia and Response to Neoadjuvant Chemotherapy for Muscle-Invasive Bladder Cancer

INTRODUCTION

The objective of the study was to determine whether sarcopenia is associated with pathologic and survival outcomes for patients with muscle-invasive bladder cancer (MIBC) treated with neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC).

PATIENTS AND METHODS

We identified MIBC patients treated with cisplatin-based NAC in our cystectomy registry from 2000 to 2016. Pre- and post-NAC computed tomography images were analyzed with BodyCompSlicer, a validated body composition assessment tool. Sarcopenia was defined as a skeletal muscle index (SMI) below sex-specific international consensus values. Associations of clinical features with pathologic downstaging (<ypT2), major (Clavien III-V) complications, and cancer-specific mortality (CSM) were modeled using multivariable logistic and Cox proportional hazard regression models.

RESULTS

A total of 183 patients were identified. Median follow-up was 3.0 years (interquartile range, 1.8-5.0), during which time 79 patients died, including 62 of bladder cancer. SMI declined by a median of 8.4% during NAC treatment. In multivariable logistic regression, neither pretreatment sarcopenia nor the amount of muscle mass loss during NAC was associated with downstaging to <ypT2 disease (P > .05). Meanwhile, only post-NAC sarcopenia (hazard ratio, 1.90; 95% confidence interval, 1.02-3.56; P = .04) was independently associated with an increased risk of CSM.

CONCLUSION

Sarcopenia after NAC and before RC appeared to be prognostic. Although skeletal muscle mass declined significantly during NAC, neither the degree of muscle loss nor pretreatment SMI were significantly associated with downstaging after NAC and RC. These data do not support the use of sarcopenia as a risk stratification tool for selection of patients for or monitoring response to NAC.

Reloading Promotes Recovery of Disuse Muscle Loss by Inhibiting TGFβ Pathway Activation in Rats After Hind Limb Suspension

OBJECTIVE

The purpose of this paper was to study the effect of transforming growth factor beta (TGFβ) signaling pathway on reloading-mediated restoration of disuse muscle loss induced by hind limb suspension in rats.

DESIGN

Rats were divided into 4 groups: control group (CON), HLS group (hind limb suspension for 2 weeks), HLS + R group (hind limb suspension for 2 weeks followed by 2 weeks of natural reloading), and HRS + E group (hind limb suspension for 2 weeks followed by 2 weeks of treadmill exercise). Body weight, and weight and protein concentration of gastrocnemius were determined. The expression of members of canonical and noncanonical TGFβ signaling pathways, including TGFβ1, myostatin (MSTN), phospho-smad2/3, phospho-mitogen-activated protein kinases (p38, JNK1/2, and extracellular signal-regulated kinase 1 [ERK1]/ERK2), as well as the corresponding downstream effectors of muscle mass-p21, Pax7, MyoD, and MyoG-was determined at protein or messenger RNA (mRNA) levels.

RESULTS

Reloading increased MyoD mRNA and restored the decreased gastrocnemius weight/body weight ratio, protein concentration of gastrocnemius, phospho-ERK2, Pax7 and the increased TGFβ1, MSTN, phospho-smad2/3, phospho-p38, phospho-JNK1/2, and p21 induced by hind limb suspension. Moreover, the effects of exercise reloading on the restoration of gastrocnemius weight/body weight ratio, TGFβ1, MSTN, phospho-smad2, phospho-p38, phospho-JNK2, Pax7, as well as the induction of MyoD mRNA were stronger than those of natural reloading.

CONCLUSIONS

Disuse muscle loss can be recovered by reloading in an intensity-dependent manner through canonical and noncanonical TGFβ signaling pathways. Pax7 and MyoD might be the effectors of TGFβ pathway in mediating the recovery effect of reloading.

Sarcopenia Is a Condition With Increasing Importance in Medical Oncology

A recent study reported that routinely screening for sarcopenia and nutritional status was helpful in determining toxicity and treatment in patients with non-small cell lung cancer. Although a decrease in muscle mass was detected in 68.8% of the participants, it is not evident what proportion the patients had true sarcopenia. Clarification of these issues may be relevant to the study results.