So Young, Yi Jeong Geun, Song Inyoung, Lee Won Woo, Chung Hyun Woo, Park Jeong Hee, Moon Sung Gyu
Department of Nuclear Medicine, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Republic of Korea.
Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Republic of Korea Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Republic of Korea
Acta Radiol. 2015 Jul;56(7):860-6. doi: 10.1177/0284185114556927. Epub 2014 Nov 18.
Skeletal muscle metastasis (SMM) in cancer patients has not been sufficiently evaluated regarding prevalence and proper method of detection.
To determine the prevalence of SMM and compare the diagnostic competencies for SMM of torso F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) and contrast-enhanced chest or abdomen CT.
We investigated 18,225 PET-CT studies of 6359 cancer patients performed from 2005 to 2012. The PET-CT studies describing potential SMM were retrieved and the corresponding medical records were reviewed. The gold standard for SMM was histopathologically-proven SMM or imaging study-based disease progression. The detectability of SMM was compared between PET-CT and contrast-enhanced CT.
Twenty-six patients had 84 SMM lesions, representing a SMM prevalence of 0.41%. Lung cancer was the most common SMM-associated malignancy (54%) and the gluteal/pelvic girdle muscle was the most frequently involved SMM site (37%). All 84 SMM lesions were visualized on PET-CT (100%). Of these PET-CT positive 84 SMM lesions, 51 lesions were in the CT field of view (FOV) (61%), whereas 33 lesions were out of the CT FOV (39%). Among these 51 lesions, 17 lesions showed rim-enhancing nodules/masses (33%), eight lesions showed homogeneously enhancing nodules (16%), three lesions showed heterogeneously enhancing nodules (6%), and 23 SMM lesions (45%) were non-diagnostic by CT. All 51 SMM lesions within CT FOV were detected on PET-CT (100%), whereas only 28 were visualized on CT (54.9%), resulting in a significant difference (P < 0.005). On average, 2.6 more organs with concomitant metastases were found when SMM was revealed by PET-CT.
The prevalence of SMM was as low as 0.41% in the current large cohort of cancer patients. Torso PET-CT was a more competent modality than contrast-enhanced CT in the detection of SMM.
癌症患者的骨骼肌转移（SMM）在患病率和合适的检测方法方面尚未得到充分评估。
确定SMM的患病率，并比较躯干F-18氟脱氧葡萄糖（FDG）正电子发射断层扫描-计算机断层扫描（PET-CT）和胸部或腹部增强CT对SMM的诊断能力。
我们调查了2005年至2012年期间对6359例癌症患者进行的18225次PET-CT检查。检索描述潜在SMM的PET-CT检查，并查阅相应的病历。SMM的金标准是组织病理学证实的SMM或基于影像学研究的疾病进展。比较PET-CT和增强CT对SMM的可检测性。
26例患者有84个SMM病灶，SMM患病率为0.41%。肺癌是最常见的与SMM相关的恶性肿瘤（54%），臀肌/骨盆带肌肉是最常受累的SMM部位（37%）。所有84个SMM病灶在PET-CT上均可见（100%）。在这84个PET-CT阳性的SMM病灶中，51个病灶在CT视野（FOV）内（61%），而33个病灶在CT FOV外（39%）。在这51个病灶中，17个病灶表现为环形强化结节/肿块（33%），8个病灶表现为均匀强化结节（16%），3个病灶表现为不均匀强化结节（6%），23个SMM病灶（45%）CT无法诊断。CT FOV内的所有51个SMM病灶在PET-CT上均被检测到（100%），而CT上仅28个病灶可见（54.9%），差异有统计学意义（P<0.005）。当PET-CT显示SMM时，平均多发现2.6个伴有转移的器官。
在当前这个大型癌症患者队列中，SMM的患病率低至0.41%。在检测SMM方面，躯干PET-CT比增强CT更具优势。
