肿瘤相关性肌少症研究进展

肌少症是一种与恶性肿瘤及其治疗方式密切相关的疾病,是以进行性的全身广泛性骨骼肌质量下降和力量降低为主要特征的综合征,可导致身体残疾、生活质量下降,甚至死亡等不良预后事件的发生。肌少症可能是由年龄、营养不良、炎症、肿瘤、消耗性疾病等多种因素参与的疾病状态,而恶性肿瘤及相关化疗所引起的肌少症多与炎症反应、氧化应激、线粒体损伤等有关。本文对近年来肿瘤相关性肌少症的检测方法、发病机制、临床特征及干预措施等进行综述。     

慢性肝病相关肌少症的影像学进展

肌少症是一组以骨骼肌质量减少、功能减退为主要特征的临床综合征,也是慢性肝病的并发症之一。影像学检查不仅能够反映肌肉结构和成分的变化,还可以定量评估肌肉的横截面积、体积以及肌肉内脂肪含量,是评估肌少症肌肉质量的重要工具。就双能X线吸收测定（DXA）、超声、CT、外周定量CT（pQCT）及MRI在慢性肝病肌少症中的临床应用及研究进展予以综述。     

基于定量CT分析肝硬化患者肌少症、腰椎骨密度和肝脏脂肪含量的相关性

【摘要】目的：基于定量CT（QCT）探讨肝硬化患者中肌少症、腰椎骨密度（BMD）和肝脏脂肪含量的相关性。方法：将2019年7月－2021年12月在本院诊断为肝硬化的163例患者（肝硬化组）及年龄、性别相匹配的100例健康体检者（对照组）纳入本研究。所有被试者行腹部CT平扫。采用QCT Pro软件测量在每例受试者L3椎体水平骨骼肌面积（SMA-L3）、腰椎BMD、肝脏脂肪分数（Fat%-QCT）。根据Child-Pugh评分,将肝硬化患者分为Child-Pugh A级、B级和C级三组。L3椎体水平骨骼肌指数（SMI-L3）为SMA-L3/身高2。根据男性患者SMI-L3＜50cm2/m2,女性患者SMI-L3＜39cm2/m2将肝硬化患者分为肌少症组和非肌少症组。结果：肝硬化组SMI-L3及腰椎BMD均低于对照组（P＜0.05）,Fat%-QCT高于对照组（P＜0.001）。Child-Pugh A、B、C级肝硬化患者肌少症发生率逐渐增加（P＜0.05）,C级患者的Fat%-QCT高于A级和B级（P＜0.001）。肝硬化患者肌少症组的年龄高于非肌少症组,腰椎BMD低于非肌少症组（P＜0.001）。多元逻辑回归分析显示,女性、年龄及合并肌少症是肝硬化患者骨质疏松的独立危险因素（P＜0.05）。结论：随着肝功能的下降,肝硬化患者肌少症发生率和肝脏脂肪含量逐渐增高;肝硬化伴肌少症患者更易发生骨质疏松。     

基于定量CT对炎症性肠病病人骨肌含量变化的初步研究

目的 利用定量CT(QCT)研究新诊断炎症性肠病（IBD）病人的骨肌含量,并探讨不同腰腹肌群肌量和骨量的变化特点及其相关性。方法 收集性别、年龄相匹配的IBD病人（男69例,女21例）及健康对照（HC）（男65例,女25例）各90例,使用QCT测定IBD组和HC组的L1～L3椎体松质骨骨密度（BMD）及L3椎体中心层面的6个腰腹肌肌群（总骨骼肌、腹壁肌群、腹直肌、椎旁肌群、腰大肌及椎后肌）的肌量并计算骨骼肌指数（SMI）。采用独立样本t检验或Mann-Whitney U检验比较2组间BMD、SMI,以及IBD病人各肌群SMI变化量及变化率的差异。采用卡方检验比较不同肌群SMI值对肌肉减少症检出率的差异。采用Pearson或Spearman法分析各肌群的SMI与腰椎BMD变化之间的相关性。结果 IBD组的BMD及各肌群的SMI均低于HC组（均P<0.05）;女性中,IBD组的BMD以及除总骨骼肌外的其他肌群SMI均低于HC组（均P<0.05）。IBD组的总骨骼肌和腰大肌SMI对肌肉减少症的检出率均高于HC组（均P<0.05）;2组中女性使用总骨骼肌SMI对肌肉减少症检出...     

双能X线吸收法在肌少症诊治中的研究进展

肌肉减少症（简称肌少症）是以广泛的、渐进的骨骼肌质量和力量减少或丧失为特点，并可能导致机体残疾、生活质量下降、甚至死亡的综合征。肌少症可导致罹患者行动障碍、跌倒及骨折风险增加，从而造成日常生活能力丧失和残疾等严重后果。双能X线吸收法（DXA）具有经济、快速、可重复性强、辐射剂量小及能同时呈现肌肉、脂肪和骨量等优点，现已成为研究及临床应用中估测肌肉质量的首选方法。笔者就DXA肌肉质量测定在肌少症诊疗中的研究进展进行综述。     

颞肌厚度作为骨骼肌减少症的标志，与胶质母细胞瘤病人预后的相关性研究

正摘要目的颞肌厚度(TMT)是骨骼肌减少症的一个重要标志,与脑转移、胶质母细胞瘤复发和病人的生存预期相关。通过颅脑 MRI 扫描,评估胶质母细胞瘤病人脑 TMT 及其与     

消化系统恶性肿瘤相关肌少症的影像学研究进展

肌少症是一种以肌量减少、肌功能下降为主要特征的系统性疾病。肌少症与消化系统恶性肿瘤术后恢复情况密切相关。双能X线吸收测量仪(DXA)、定量CT(QCT)及MRI等影像方法可用于评估消化系统恶性肿瘤相关肌少症,可以测量其肌量和脂肪量,MRI还可探测肌肉水肿、肌间脂肪浸润及纤维化等改变,反映组织结构和成分变化,进而对消化系统恶性肿瘤病人的预后进行监测及疗效评估。     

肌肉减少症鼠类动物模型评估方法的研究进展

【摘要】肌肉减少症是一种进行性和全身性的老年骨骼肌疾病,表现为肌肉力量、质量和功能的全面丧失,严重易致跌倒和死亡。目前全球肌少症的罹患人数随着人口老龄化的加剧不断上升,这将给社会及医疗系统造成沉重负担。目前,肌肉减少症的确切分子机制仍然未知,早期诊断与有效的治疗药物仍然是肌肉减少症临床诊疗的难点。使用动物模型来探究解决这些问题,从而推动该领域的研究进程至关重要。然而,判断构建的模型是否可靠仍缺少有效评估方法。本文主要从肌肉力量、肌肉质量及肌肉功能三个方面对肌肉减少症鼠类动物模型的评估方法研究进展进行综述。     

离心运动引起骨骼肌过度使用损伤机理研究

目的:探讨长期离心运动引起骨骼肌过度使用损伤的发生机制。方法:12只雄性SD大鼠随机分成安静对照组(C组)和训练组(TG组)两组。训练组采用4周低强度跑台离心运动(-16°、60-90分/天,5天/周)建立过度使用损伤动物模型。第4周取股中间肌,采用透射电子显微镜观察骨骼肌细胞超微结构损伤累积;采用扫描电子显微镜观察骨骼肌神经、血管结构损伤和胶原纤维结构变化;采用Masson氏三色染色法评价骨骼肌组织的胶原纤维沉积量;采用免疫组化方法量化沉积的胶原纤维中的collagenⅠ表达,并依据collagenⅣ染色,观察肌细胞的基质膜形态变化。结果:⑴骨骼肌超微结构变化:与安静对照组比较,训练组骨骼肌超微结构异常变化,体现为Z线流、肌原纤维间隙变宽、肌原纤维降解、肌膜下线粒体聚积和肌原纤维内线粒体降解物堆积;⑵肌膜结构变化:训练组肌膜结构完整,没有撕裂现象;⑶骨骼肌神经和血管结构变化:与安静对照组比较,TG组神经和血管结构损伤,且collagenⅠ过度沉积在神经和血管周围;⑷肌内膜和肌束膜结构变化:与安静对照组比较,训练组肌束膜胶原纤维结构紊乱,且厚度增加的肌内膜尤其是肌束膜collagenⅠ过度沉积。结论:⑴长期重复性离心运动导致骨骼肌过度使用损伤,包括骨骼肌细胞超微结构损伤累积,神经、血管和肌束膜纤维化;⑵骨骼肌细胞超微结构损伤累积导致肌内膜尤其是肌束膜collagenⅠ过度沉积,以保护肌膜免受进一步损伤;⑶collagenⅠ在肌内膜尤其是肌束膜持续沉积增加了结缔组织硬度,造成骨骼肌神经和血管结构损伤累积。表明骨骼肌细胞超微结构损伤累积导致了过度使用损伤症状发生。     

肌松药监测的临床进展

全身麻醉是目前临床麻醉中普遍应用的麻醉方法。肌松药是骨骼肌松弛药的简称,可选择性作用于神经肌肉接头,暂时干扰正常神经肌肉的兴奋传递,从而使得肌肉松弛。在临床上肌松药监测的应用日趋增多,周围神经刺激器是监测神经肌肉阻滞程度的重要手段,本文主要介绍肌松药监测评定方法及常用刺激模式。     

Assessment of sarcopenia and changes in body composition after neoadjuvant chemotherapy and associations with clinical outcomes in oesophageal cancer

Objectives

Sarcopenia and changes in body composition following neoadjuvant chemotherapy (NAC) may affect clinical outcome. We assessed the associations between CT body composition changes following NAC and outcomes in oesophageal cancer.

Methods

A total of 35 patients who received NAC followed by oesophagectomy, and underwent CT assessment pre- and post-NAC were included. Fat mass (FM), fat-free mass (FFM), subcutaneous fat to muscle ratio (FMR) and visceral to subcutaneous adipose tissue ratio (VA/SA) were derived from CT. Changes in FM, FFM, FMR, VA/SA and sarcopenia were correlated to chemotherapy dose reductions, postoperative complications, length of hospital stay (LOS), circumferential resection margin (CRM), pathological chemotherapy response, disease-free survival (DFS) and overall survival (OS).

Results

Nine (26 %) patients were sarcopenic before NAC and this increased to 15 (43 %) after NAC. Average weight loss was 3.7 %?±?6.4 (SD) in comparison to FM index (?1.2?±?4.2), FFM index (?4.6?±?6.8), FMR (?1.2?±?24.3) and VA/SA (?62.3?±?12.7). Changes in FM index (p?=?0.022), FMR (p?=?0.028), VA/SA (p?=?0.024) and weight (p?=?0.007) were significant univariable factors for CRM status. There was no significant association between changes in body composition and survival.

Conclusions

Loss of FM, differential loss of VA/SA and skeletal muscle were associated with risk of CRM positivity.

Key Points

? Changes in CT body composition occur after neoadjuvant chemotherapy in oesophageal cancer. ? Sarcopenia was more prevalent after neoadjuvant chemotherapy. ? Fat mass, fat-free mass and weight decreased after neoadjuvant chemotherapy. ? Changes in body composition were associated with CRM positivity. ? Changes in body composition did not affect perioperative complications and survival.     

Markers of sarcopenia quantified by computed tomography predict adverse long-term outcome in patients with resected oesophageal or gastro-oesophageal junction cancer

Objectives

To assess the impact of sarcopenia and alterations in body composition parameters (BCPs) on survival after surgery for oesophageal and gastro-oesophageal junction cancer (OC).

Methods

200 consecutive patients who underwent resection for OC between 2006 and 2013 were selected. Preoperative CTs were used to assess markers of sarcopenia and body composition (total muscle area [TMA], fat-free mass index [FFMi], fat mass index [FMi], subcutaneous, visceral and retrorenal fat [RRF], muscle attenuation). Cox regression was used to assess the primary outcome parameter of overall survival (OS) after surgery.

Results

130 patients (65 %) had sarcopenia based on preoperative CT examinations. Sarcopenic patients showed impaired survival compared to non-sarcopenic individuals (hazard ratio [HR] 1.87, 95 % confidence interval [CI] 1.15–3.03, p?=?0.011). Furthermore, low skeletal muscle attenuation (HR 1.91, 95 % CI 1.12–3.28, p?=?0.019) and increased FMi (HR 3.47, 95 % CI 1.27–9.50, p?=?0.016) were associated with impaired outcome. In the multivariate analysis, including a composite score (CSS) of those three parameters and clinical variables, only CSS, T-stage and surgical resection margin remained significant predictors of OS.

Conclusion

Patients who show signs of sarcopenia and alterations in BCPs on preoperative CT images have impaired long-term outcome after surgery for OC.

Key Points

? Sarcopenia is associated with impaired OS after surgery for oesophageal cancer.? Other body composition parameters are also associated with impaired survival.? This influence on survival is independent of established clinical parameters.? Sarcopenia provides a better estimation of cachexia than BMI.? Sarcopenia assessment could be considered in risk/benefit stratification before oesophagectomy.

     

Transiently Altered Distribution of F-18 FDG in a Patient with Subacute Thyroiditis

F-18 fluorodeoxyglucose (FDG) is a highly influential radiotracer that provides valuable information in many cancer types. However, the normal biodistribution of F-18 FDG is often variable and can be altered by intrinsic or iatrogenic factors. We report a case of diffuse symmetrically increased skeletal muscle uptake and relatively decreased hepatic uptake on F-18 FDG PET/CT in a 57-year-old female with pulmonary adenocarcinoma. Detailed clinical evaluation and retrospective radiologic evaluation revealed that she had been diagnosed with subacute thyroiditis 2 weeks ago. After 6 weeks, F-18 FDG distribution was normalized at the follow-up PET/CT study.     

Multiple muscle metastases from lung cancer detected by FDG PET/CT

A 71-year-old man with right lung mass, who was recently diagnosed histopathologically with pulmonary adenocarcinoma, was referred for staging of the primary tumor. Whole-body F-18 fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) demonstrated multiple hypermetabolic foci in various skeletal muscle localizations, suggesting extensive metastatic muscle involvements in addition to increased FDG uptake in the primary tumor. Subsequent biopsy and histopathological study confirmed muscle metastasis from lung adenocarcinoma. Skeletal muscle metastasis from lung cancer is rare, but multiple muscle metastases are even more unusual. FDG PET/CT is able to detect unexpected metastatic involvements such as multiple muscle metastases in lung cancer patients.     

Helical CT of skeletal muscle metastases from primary carcinomas

OBJECTIVE: To determine the clinical and helical CT findings in patients with skeletal muscle metastases from carcinoma, we reviewed the cases of 15 consecutive patients who had muscle metastases diagnosed by contrast-enhanced helical CT. MATERIALS AND METHODS: Between February 1992 and August 1997, 15 patients (30 lesions) had metastatic disease to muscle from primary carcinoma diagnosed by helical CT in our institution. Patient data and imaging findings were retrospectively reviewed. RESULTS: Ten of 15 patients (67%) were known to have a malignancy at the time of CT. Patients complained of pain at the site of skeletal muscle metastases in five (17%) of 30 lesions, and in 11 (37%) of 30 lesions a mass was palpable. Lesion size averaged 3.2 cm (range, 0.7-7.8 cm). Thirteen of 15 patients had metastatic disease elsewhere at the time of skeletal muscle metastasis diagnosis. Muscles and other structures most commonly involved by metastatic disease included erector spinae (n = 9), psoas (n = 4), rotator cuff (n = 4), gluteal (n = 3), and abdominal (n = 3). The most common appearance of metastatic disease to muscle on contrast-enhanced helical CT was that of a rim-enhancing mass with central hypoattenuation in 25 (83%) of 30 lesions. CONCLUSION: Metastatic disease to skeletal muscle tends to be found in people with advanced-stage neoplasms. It may be an incidental finding on CT because pain is an uncommon feature; a minority of lesions were palpable in our series. The most common appearance on contrast-enhanced helical CT is a rim-enhancing intramuscular lesion with central hypoattenuation.     

CT and arteriography in the evaluation of indirect myocardial revascularization with a free-muscle transplant: initial experience

PURPOSE: To examine patients with advanced cardiovascular disease with radiology after indirect myocardial revascularization with a free-skeletal-muscle transplant and to determine whether the attached vessel remains patent over the middle and long terms. MATERIALS AND METHODS: In 10 patients with advanced, inoperable cardiovascular disease treated with indirect myocardial revascularization with a free-muscle transplant, radiologic follow-up was performed postoperatively and every 6 months. All 10 patients underwent selective arteriography of the anastomosed vessel and contrast material-enhanced helical computed tomography (CT) (transverse sections and reconstructions). RESULTS: All patients showed adequate vascular conditions postoperatively, as did nine of 10 patients after 1 year. In one patient, the anastomosed artery was occluded. CT showed time-dependent muscle degeneration in all patients. Postoperative, contrast-enhanced, superselective CT showed an area of high-attenuating uptake in the muscle transplant in all patients. After 1 year, CT depicted perfusion defects of the skeletal muscle in two patients. In eight patients, however, small vascular bridges from the skeletal muscle to the myocardium were detected. Radiologic results correlated well with clinical outcome and stress electrocardiograms. CONCLUSION: Helical intraarterial CT and arteriography were sensitive in depicting enhancement and remaining vital function in nine of 10 patients after indirect myocardial revascularization with a free-muscle transplant. This combination seems promising for postoperative examination in such patients.     

(11)C]Choline positron emission tomography/computed tomography for staging and restaging of patients with advanced prostate cancer

INTRODUCTION: To evaluate [(11)C]Choline positron emission tomography (PET)/computed tomography (CT) for staging and restaging of patients with advanced prostate cancer and to compare the diagnostic performance of PET, CT and PET/CT. METHODS: Forty-five consecutive patients with advanced prostate cancer underwent [(11)C]Choline-PET/CT between 5/2004 and 2/2006. RESULTS: Overall, 295 lesions were detected: PET alone, 178 lesions; diagnostic CT, 221 lesions; PET/CT (low-dose CT), 272 lesions; PET/CT (diagnostic CT), 295 lesions. Two thirds of the lesions were located in the bone; one third in the prostate, lymph nodes, periprostatic tissue and soft tissue (lung, liver). The use of diagnostic CT did not result in a statistically significant difference with respect to lesion localization certainty and lesion characterization (P=.063, P=.063). PET-negative but PET/CT-positive lesions were mostly localized in the bone (78%, 91/117) as were PET-positive and CT-negative lesions (72%, 53/74). Of the latter, 91% (48/53) represented bone marrow and 9% (5/53) cortical involvement. CONCLUSIONS: Staging and restaging with [(11)C]Choline PET/CT in patients with advanced prostate cancer improve the assessment of local and regional recurrent as well as metastatic disease including skeletal manifestations. [(11)C]Choline PET/CT (with a low-dose CT) results in improved localization and lesion characterization. [(11)C]Choline PET/CT provides an added value for skeletal manifestations. [(11)C]Choline PET/CT changed disease management in 11 (24%) of 45 patients with advanced prostate cancer.     

CT findings of metastatic breast carcinoma involving muscle

Hematogenous metastatic disease to skeletal muscle is a very unusual occurrence and is seldom diagnosed clinically. This case report demonstrates the CT findings of metastatic breast cancer to skeletal muscle of the neck.