Piloting a training program in computed tomography (CT) skeletal muscle assessment for Registered Dietitians

Explanatory sequential mixed-methods approach to understand how registered dietitians implemented computed tomography skeletal muscle assessments in clinical practice

BACKGROUND

There is a need to adopt valid techniques to assess skeletal muscle (SM) in clinical practice. SM can be precisely quantified from computed tomography (CT) images. This study describes how registered dietitians (RDs), trained to quantify SM from CT images, implemented this technique in clinical practice.

METHODS

This was an explanatory sequential mixed-methods design with a quantitative and a qualitative phase. RDs collected data describing how they implemented CT SM assessments in clinical practice, followed by a focus group exploring barriers and enablers to using CT SM assessments.

RESULTS

RDs (N = 4) completed 96 CT SM assessments, with most (94%, N = 90/96) taking <15 min to complete. RDs identified reduced muscle mass in 63% (N = 45/72) of men and 71% (N = 17/24) of women. RDs used results of CT SM assessments to increase protein composition of the diet/nutrition support, advocate for initiation or longer duration of nutrition support, coordinate nutrition care, and provide nutrition education to patients and other health service providers. The main barriers to implementing CT SM assessments in clinical practice related to cumbersome health system processes (ie, CT image acquisition) and challenges integrating CT image analysis software into the health system computing environment.

CONCLUSION

Preliminary results suggest RDs found CT SM assessments positively contributed to their nutrition care practice, particularly in completing nutrition assessments and in planning, advocating for, and implementing nutrition interventions. Use of CT SM assessments in clinical practice requires innovative IT solutions and strategies to support skill development and use in clinical nutrition care.

Predictive impact of sarcopenia in advanced non-small cell lung cancer patients treated with immune checkpoint inhibitors: A retrospective study

Background

Sarcopenia, characterised by an ongoing loss of skeletal muscle mass and reduced strength and function, is frequently observed in patients with non-small cell lung cancer (NSCLC). However, the relationship between sarcopenia and the prognosis of NSCLC treated with immune checkpoint inhibitors (ICIs) remains unclear. This aimed to assess whether sarcopenia is an independent prognostic factor for survival in patients with advanced NSCLC receiving ICIs.

Methods

For this retrospective cohort study, we analysed the medical records of patients attending our hospital aged 18-75 years who were newly diagnosed with stage IIIB to stage IV NSCLC, and who had received ICIs as first- or second-line therapy between May 2019 and April 2022. The skeletal muscle index (SMI) was calculated from computed tomography (CT) images and relevant clinical characteristics within 4 weeks of initiating treatment and used to diagnose sarcopenia status. The Kaplan-Meier method and log-rank test were used to calculate and compare patients' progression-free survival (PFS). Cox proportional hazard regression was used to examine the associations between sarcopenia and survival outcomes. The chi-square test was used to compare treatment response outcomes, such as the objective response rate (ORR), disease control rate (DCR), and immunotherapy-related adverse events (irAEs), between individuals with and without sarcopenia. Additionally, the Student's t-test was utilised to compare SMI values between patients by their objective response (OR) and disease control (DC). Finally, the Mann-Whitney U test was used to compare nutritional and inflammatory indicators between the sarcopenia groups.

Results

The study enrolled 70 patients, of whom 34 (48.6%) were diagnosed with sarcopenia. The median PFS of patients with and without sarcopenia was 7.5 vs. 13.4 months, respectively (p = 0.006). The proportional hazards regression analysis showed sarcopenia to be an independent prognostic factor for shorter PFS (hazard ratio (HR): 0.504, 95% CI: 0.265-0.962, p = 0.038). Using chi square tests, we found significant differences in the ORR (20.59% vs. 58.33%, p = 0.001) and occurrence of any irAEs (44.1% vs. 22.2%, p = 0.028) between the sarcopenia and the non-sarcopenia groups, respectively. The Student's t-test showed a significant difference in SMI between the ORR group and the non-ORR group (49.99 ± 7.00 vs. 42.98 ± 2.18 cm2/m2, p = 0.0015). While the sarcopenia group were with significantly a lower CD4+/CD8+ ratios and a higher C-reactive protein (CRP) level (p = 0.026, p = 0.011, respectively). Conclusions: This study found that sarcopenia is a significant predictor of a poor prognosis for patients with advanced NSCLC receiving ICIs. Multiple inflammatory and immune functions related to prognosis also differ by sarcopenia status.

Adverse effects of systemic cancer therapy on skeletal muscle: myotoxicity comes out of the closet

PURPOSE OF REVIEW

Systemic cancer therapy-associated skeletal muscle wasting is emerging as a powerful impetus to the overall loss of skeletal muscle experienced by patients with cancer. This review explores the clinical magnitude and biological mechanisms of muscle wasting during systemic cancer therapy to illuminate this adverse effect. Emerging strategies for mitigation are also discussed.

RECENT FINDINGS

Clinical findings include precise, specific measures of muscle loss over the course of chemotherapy, targeted therapy and immunotherapy. All these therapeutic classes associate with quantitatively important muscle loss, independent of tumor response. Parallel experimental studies provide understanding of the specific molecular basis of wasting, which can include inhibition of protein synthesis, proliferation and differentiation, and activation of inflammation, reactive oxygen species, autophagy, mitophagy, apoptosis, protein catabolism, fibrosis and steatosis in muscle. Strategies to mitigate these muscle-specific adverse effects of cancer therapy remain in the earliest stages of development.

SUMMARY

The adverse side effect of cancer therapy on skeletal muscle has been largely ignored in the development of cancer therapeutics. Given the extent to which loss of muscle mass and function can bear on patients' function and quality of life, protection/mitigation of these side effects is a research priority.

A large, multi-centre prospective study demonstrating high prevalence of malnutrition associated with reduced survival in ambulatory systemic anti-cancer therapy patients

BACKGROUND & AIMS

The nutritional status of cancer patients is highly variable, and known to impact on clinical outcomes. To date, no large study evaluating the nutritional status of Irish cancer patients has been reported. The aim of this study was to describe the nutritional status, using gold standard methods, of a large cohort of ambulatory oncology patients receiving Systemic Anti-Cancer Therapy and to assess the impact of abnormal body composition phenotypes on survival.

METHODS

A prospective study in adults undergoing Systemic Anti-Cancer Therapy for solid tumours enrolled patients between 2012 and 2016. Baseline details were collected incorporating demographics, cancer pathology, lifestyle, body composition (by computed tomography (CT), and inflammatory status. Skeletal muscle index (SMI) and mean muscle attenuation (MA) were obtained from CT images and categorised to low muscle mass and low MA using previously published sex specific cut points. Survival was monitored for a median of 25 months [IQR:10-46 months]. Survival analyses were conducted using multivariate Cox Proportional Hazards Models.

RESULTS

Of 1015 patients recruited, 940 patients with an evaluable CT were included in this analysis. Median age was 64 years [IQR 55-71] and 56% were male. Colorectal cancer (28%) and gastro-oesophageal (16%) were the most common diagnoses and 58% of patients had stage IV disease. Despite 56% being overweight or obese (BMI >25 kg/m²), 52% were weight losing and 17% had lost >10% body weight. Cancer Cachexia (CC) was present in 42%, 39% had low muscle mass (MM) (sarcopenia) and 45% had low MA. Overall, 73% of patients exhibited an abnormal body composition (BC) phenotype (≥1 of CC, low MM/MA). Overall survival was significantly lower in those with abnormal BC phenotype, independent of site, stage, sex, ECOG and mGPS (HR: 1.416 [95% CI: 1.069-1.875], p = 0.015).

CONCLUSIONS

Malnutrition and abnormal body composition phenotypes are common in cancer, but are often masked by adiposity. Appropriate screening and diagnostic tools should consider this co-presentation of overweight and obesity, alongside muscle depletion. Given that abnormal body composition phenotypes detectable only via CT are associated with reduced survival, these should be more widely employed to identify patients at risk of poor prognosis, and allow potentially more effective, early intervention.

Sarcopenia Was a Poor Prognostic Predictor for Patients With Advanced Lung Cancer Treated With Immune Checkpoint Inhibitors

Background

It remains not well known whether skeletal muscle mass (SMM) loss has any impact on the effectiveness of immune checkpoint inhibitors (ICIs) in patients with advanced lung cancer. We aimed to evaluate the association between SMM and clinical outcome of patients with advanced lung cancer receiving ICIs as first line or second line.

Materials and Methods

From March 1st, 2019 to March 31st, 2021 at our hospital, 34 patients with advanced lung cancer treated with first-line or second-line ICIs were enrolled retrospectively. The estimation of skeletal muscle index (SMI) for sarcopenia was assessed at the level of the third lumbar vertebra (L3) on computed tomography (CT) images obtained within 4 weeks before initiation of ICIs treatment. The impact of sarcopenia (low SMI) on progression free survival (PFS) was analyzed using Kaplan-Meier method and log-rank tests. The effect of various variables on PFS was evaluated using Cox proportional hazards regression model with univariate and multivariate analysis. The impact on treatment response including objective response rate (ORR) and disease control rate (DCR) and immunotherapy related adverse events (irAEs) between patients with and without sarcopenia was compared by the chi-squared test. The comparison of SMI value between patients with objective response (OR), disease control (DC) and those without OR and DC was used student t-test or Mann-Whitney U test.

Results

Both in univariate and multivariate analysis, sarcopenia and treatment lines were the predictive factors for PFS (p < 0.05). Patients with sarcopenia had significantly shorter PFS than that of non-sarcopenic ones [6.57 vs. 16.2 months, hazard ratios (HR) = 2.947 and 3.542, and 95% confidence interval (CI): 1.123–13.183 and 1.11–11.308, p = 0.022 and 0.033]. No significant difference in ORR and irAEs was found. Patients with sarcopenia had lower DCR than those without sarcopenia. The mean SMI value of DCR group and non-DCR group was 32.94 ± 5.49 and 44.77 ± 9.06 cm²/m², respectively (p = 0.008).

Conclusion

Sarcopenia before immunotherapy might be a significant predictor for poor prognosis including shorter PFS and lower DCR in patients with advanced lung cancer treated with ICIs as first line or second line.