Does neoadjuvant chemotherapy regimen affect sarcopenia status in patients with breast cancer?

Genetic overlap between breast cancer and sarcopenia: exploring the prognostic implications of SLC38A1 gene expression

BACKGROUND

Sarcopenia, an age-related syndrome characterized by a decline in muscle mass, not only affects patients' quality of life but may also increase the risk of breast cancer recurrence and reduce survival rates. Therefore, investigating the genetic mechanisms shared between breast cancer and sarcopenia is significant for the prevention, diagnosis, and treatment of breast cancer.

METHODS

This study downloaded gene expression datasets and clinical data related to breast cancer and skeletal muscle aging from the GEO database. Data preprocessing, integration, differential gene identification, functional enrichment analysis, and construction of protein-protein interaction networks were performed using R language. Subsequently, COX proportional hazards model analysis and survival analysis were conducted, and survival curves and nomograms were generated. The expression levels of genes in tissues were detected using qRT-PCR, and the Radiant DICOM viewer software was used to delineate the pectoralis major muscle area in CT images.

RESULTS

We identified 152 differentially expressed genes (P < .05) and 226 sarcopenia-related genes (r > .4) associated with skeletal muscle aging. The TCGA-BRCA dataset revealed 106 genes associated with breast cancer (P < .05, logFC = 1). Functional enrichment analysis indicated significant enrichment in cell proliferation and growth pathways. The PPI network identified critical molecules involved in muscle aging and tumor progression. After dimensionality reduction, a strong correlation was observed between the expression of the muscle aging-related gene set and the prognosis of breast cancer patients (P < .01). The expression of SLC38A1 identified through multivariate COX analysis was significantly associated with poor prognosis in breast cancer patients (P = .03). Incorporating SLC38A1 expression, the prognostic model precisely forecasted breast cancer survival (P < .01). External validation confirmed the higher expression of the SLC38A1 gene in breast cancer tissues compared to adjacent non-cancerous tissues (P < .01). The SLC38A1 index, calculated in combination with the patient's age and BMI, can optimize the prognostic prediction model, providing a powerful tool for personalized treatment of breast cancer.

CONCLUSION

High SLC38A1 gene expression was significantly associated with poor prognosis in breast cancer patients. The combination of SLC38A1 expression and the pectoralis major muscle area provided an optimized prognostic prediction model, offering a potential tool for personalized breast cancer treatment.

Effectiveness of resistance training in preventing sarcopenia among breast cancer patients undergoing chemotherapy: A systematic review and meta-analysis

BACKGROUND

Breast cancer patients undergoing chemotherapy experience body composition changes impacting treatment outcomes. The role of resistance training in mitigating chemotherapy-induced sarcopenia in breast cancer patients is not well defined.

AIMS

This study aims to assess the efficacy of resistance training in preventing sarcopenia among breast cancer patients undergoing chemotherapy.

METHODS

A systematic search was conducted across PubMed, EMBASE, Medline, the Cochrane Library, and CINAHL until May 5, 2023. Selected literature focused on the effects of resistance training on body fat, muscle mass, muscle strength, and physical performance in breast cancer patients undergoing chemotherapy. Cochrane Risk of Bias tool version 2.0 was employed for quality assessment, and data were analyzed using Comprehensive Meta-Analysis version 2.0.

RESULTS

Eleven randomized controlled trials (RCTs) showed that resistance training had a significant positive impact on reducing body fat (SMD = -0.250, 95% CI [-0.450, -0.050]), increasing lean body mass (SMD = 0.374, 95% CI [0.178, 0.571]), and enhancing handgrip strength at both the affected site (SMD = 0.326, 95% CI [0.108, 0.543]) and the nonaffected site (SMD = 0.276, 95% CI [0.059, 0.492]). Additionally, significant improvements were observed in leg press strength (SMD = 0.598, 95% CI [0.401, 0.796]) and overall physical performance (SMD = 0.671, 95% CI [0.419, 0.923]).

LINKING EVIDENCE TO ACTION

Resistance training is a recommended intervention for reducing body fat, increasing muscle mass, muscle strength, and enhancing physical performance in breast cancer patients undergoing chemotherapy. Ideal low-intensity resistance training programs span 8-24 weeks, with 20-to-90-min sessions 2-4 times weekly. Regimens generally entail 8-12 repetitions at 40%-90% of one-repetition maximum test, with free-weight resistance training targeting major muscle groups yielding substantial benefits. Further research should explore outcomes across different chemotherapy phases and investigate long-term resistance training effects for a comprehensive view.

Sarcopenia's Role in Neoadjuvant Chemotherapy Outcomes for Locally Advanced Breast Cancer: A Retrospective Analysis

BACKGROUND Sarcopenia, characterized by loss of skeletal muscle mass and function, is linked to poor outcomes in cancer patients. In breast cancer, sarcopenia has been associated with reduced treatment tolerance and survival. However, its impact on patients with locally advanced breast cancer receiving neoadjuvant chemotherapy is understudied. This study aimed to assess sarcopenia's impact on outcomes in 226 women with advanced breast cancer, pre- and post-chemotherapy. MATERIAL AND METHODS This retrospective cohort study included 226 patients with stage II-III breast cancer who received neoadjuvant chemotherapy (NAC) between 2015 and 2021. Sarcopenia was assessed using psoas muscle area (PMA) from pre- and post-NAC computed tomography scans, with a 25th percentile cut-off (415.4 mm²). Pathological response was evaluated using the Miller-Payne grading system, and survival outcomes were analyzed using Kaplan-Meier curves. Statistical significance was set at P<0.05. RESULTS The mean PMA decreased significantly after NAC (502.8 mm2 to 454.3 mm², P<0.001). Pre-NAC, sarcopenia was present in 24.8% of patients. This increased to 40.7% after NAC. Sarcopenia was more prevalent in obese patients (P<0.001), but no significant association was found between sarcopenia and pathological complete response (pCR) or survival outcomes. Although pre- and post-NAC sarcopenia did not affect recurrence or mortality, non-sarcopenic patients were more likely to achieve pCR (P=0.012). Hematologic toxicity was higher in sarcopenic patients with comorbidities (P<0.05). CONCLUSIONS Sarcopenia significantly increases after NAC but does not independently impact pathological response, recurrence, or survival in locally advanced breast cancer. Obesity and comorbid conditions are key factors influencing sarcopenia, highlighting the need for comprehensive management to mitigate treatment-related sarcopenia.

Age-related and cancer-related sarcopenia: is there a difference?

PURPOSE OF REVIEW

The aim of this review is the attempt to differentiating the pathophysiologic and clinical features of the aging-related sarcopenia from cancer-related sarcopenia. In fact, there is some controversy among the experts mainly regarding two points: is always sarcopenia, even that aging-related one, the expression of a generalized disease or may exist independently and without major alteration of the muscle function? Are always aging-related and cancer-related sarcopenia completely separated entities?

RECENT FINDINGS

Literature shows that sarcopenia, defined as simple skeletal muscle mass loss, may range from a mainly focal problem which is common in many healthy elderly people, to a component of a complex multiorgan syndrome as cancer cachexia. Disuse, malnutrition and (neuro)degenerative processes can account for most of the aging-related sarcopenias while systemic inflammation and secretion of cancer-and immune-related molecules play an additional major role in cachexia.

SUMMARY

A multimodal approach including physical exercise and optimized nutritional support are the key measures to offset sarcopenia with some contribution by the anti-inflammatory drugs in cancer patients. Results are more promising in elderly patients and are still pending for cancer patients where a more specific approach will only rely on the identification and contrast of the key mediators of the cachectic process.

Sarcopenia among treated cancer patients before and after neoadjuvant chemotherapy: a systematic review and meta-analysis of high-quality studies

BACKGROUND

Neoadjuvant chemotherapy, used to shrink tumors before surgery, is increasingly applied in clinical practice. However, retrospective studies indicate that it may increase sarcopenia rates and consequently result in an elevated occurrence rate of postoperative severe complications such as severe surgical incision infection, severe respiratory failure, and severe postoperative hemorrhage, especially in the elderly population. Currently, no systematic analysis examines the association between neoadjuvant chemotherapy and sarcopenia. This study aims to fill this gap with a comprehensive meta-analysis focused on this critical aspect of the field.

METHODS

A systematic literature search was conducted in the PubMed and Web of Science databases from their inception to January 2024. The included studies encompassed patients who received neoadjuvant chemotherapy and underwent computed tomography (CT) scans both before and after treatment to calculate skeletal muscle index (SMI) or categorize them for the presence of sarcopenia. The determination of sarcopenia status was based on well-established and validated threshold criteria. Data extraction was performed independently by two reviewers. A meta-analysis was employed to estimate the pooled odds ratio (OR) and its corresponding 95% confidence interval (95% CI) to assess the risk of neoadjuvant chemotherapy-induced muscle reduction.

RESULTS

In the 14 studies with complete categorical variable data, comprising 1853 patients, 773 patients were identified as having sarcopenia before neoadjuvant treatment and 941 patients had sarcopenia after neoadjuvant therapy. The OR and its 95% CI was calculated as 1.51 [1.31, 1.73]. Among these, 719 patients had digestive system cancer, with 357 patients having sarcopenia before neoadjuvant treatment and 447 patients after, resulting in an OR of 1.74 [1.40, 2.17]. In the remaining 1134 patients with non-digestive system cancers, 416 were identified as having sarcopenia before neoadjuvant treatment, and 494 patients had sarcopenia after, with an OR of 1.37 [1.15, 1.63]. Additionally, in seven studies with complete continuous variable data, including 1228 patients, the mean difference in the change of SMI before and after neoadjuvant treatment was  - 1.13 [- 1.65,  - 0.62]. After excluding low-quality small-sample studies with fewer than 50 patients, the same trend was observed in the analysis.

CONCLUSION

The risk of muscle reduction significantly increases in cancer patients after neoadjuvant chemotherapy and digestive system cancers tend to have a higher risk of developing sarcopenia post-treatment compared to non-digestive system cancers.

Pretreatment Sarcopenia and MRI-Based Radiomics to Predict the Response of Neoadjuvant Chemotherapy in Triple-Negative Breast Cancer

The association between sarcopenia and the effectiveness of neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC) remains uncertain. This study aims to examine the potential of sarcopenia as a predictive factor for the response to NAC in TNBC, and to assess whether its combination with MRI radiomic signatures can improve the predictive accuracy. We collected clinical and pathological information, as well as pretreatment breast MRI and abdominal CT images, of 121 patients with TNBC who underwent NAC at our hospital between January 2012 and September 2021. The presence of pretreatment sarcopenia was assessed using the L3 skeletal muscle index. Clinical models were constructed based on independent risk factors identified by univariate regression analysis. Radiomics data were extracted on breast MRI images and the radiomics prediction models were constructed. We integrated independent risk factors and radiomic features to build the combined models. The results of this study demonstrated that sarcopenia is an independent predictive factor for NAC efficacy in TNBC. The combination of sarcopenia and MRI radiomic signatures can further improve predictive performance.

Sarcopenia and malignancies: epidemiology, clinical classification and implications

Sarcopenia is a progressive systemic skeletal muscle disorder characterized by a pathological decline in muscle strength, quantity, and quality, which frequently affects the elderly population. The majority of cancer patients are of advanced age. Patients may already have sarcopenia prior to cancer development, and those with cancer are prone to developing sarcopenia due to hypercatabolism, inflammation, reduced physical fitness, anorexia, adverse effects, and stress associated with anticancer therapy. Based on the timing, sarcopenia in patients with cancer can be categorized into three: pre-existing sarcopenia before the onset of cancer, sarcopenia related to cancer, and sarcopenia related to cancer treatment. Sarcopenia not only changes the body composition of patients with cancer but also increases the incidence of postoperative complications, reduces therapeutic efficacy, impairs quality of life, and results in shortened survival. Different therapeutic strategies are required to match the cancer status and physical condition of patients with different etiologies and stages of sarcopenia. Here, we present a comprehensive review of the epidemiology and diagnosis of sarcopenia in patients with cancer, elucidate the complex interactions between cancer and sarcopenia, and provide evidence-based strategies for sarcopenia management in these patients.

Gastric Cancer with Sarcopenia: an Area Worth Focusing On

OPINION STATEMENT

Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer death worldwide, which seriously endangers human health. A number of studies have shown that sarcopenia occurs more frequently in patients with gastric cancer than in the general population and can significantly affect the disease status and survival of patients, which is of great significance in predicting the prognosis of gastric cancer. Patients with gastric cancer may suffer sarcopenia no matter before or after surgery, and the pathogenesis is complex. Abnormal nutrient metabolism and reduced exercise are the leading causes. In addition, surgical treatment and chemotherapy for gastric cancer might participate in the physiological and pathological mechanism of sarcopenia. Generally speaking, exercise and nutritional therapy are the main prevention and treatment methods for sarcopenia. But more prospective evidence is needed to establish reasonable interventions, and other drug treatments are in their infancy. For the diagnostic criteria of sarcopenia, the cut-off values of the skeletal muscle mass index obtained from CT images vary widely and need to be standardized and unified. We also need to explore simple predictors to facilitate sarcopenia risk assessment. More research is needed to formulate more appropriate treatments for gastric cancer patients with sarcopenia.

Current Therapeutic Targets in Cancer Cachexia: A Pathophysiologic Approach

Significant progress in our understanding of cancer cachexia has occurred in recent years. Despite these advances, no pharmacologic agent has achieved US Food and Drug Administration approval for this common and highly morbid syndrome. Fortunately, improved understanding of the molecular basis of cancer cachexia has led to novel targeted approaches that are in varying stages of drug development. This article reviews two major thematic areas that are driving these pharmacologic strategies, including those targeting signal mediators at the level of the CNS and skeletal muscle. Additionally, pharmacologic strategies are being tested in combination with targeted nutrients, nutrition therapy, and exercise to treat cancer cachexia. To this end, we highlight recently published and ongoing trials evaluating cancer cachexia therapies in these specific areas.

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.