Tenosynovial giant cell tumor (TSGCT) is a rare soft tissue tumor that involves the synovial lining of joints, bursae, and tendon sheaths, primarily affecting young patients (usually in the fourth decade of life). The tumor comprises two subtypes: the localized type (L-TSGCT) and the diffuse type (D-TSGCT). Although these subtypes share histological and genetic similarities, they present a different prognosis. D-TSGCT tends to exhibit local aggressiveness and a higher recurrence rate compared to L-TSGCT. Magnetic resonance imaging (MRI) is the preferred diagnostic tool for both the initial diagnosis and for treatment planning. When interpreting the initial MRI of a suspected TSGCT, it is essential to consider: (i) the characteristic findings of TSGCT—evident as low to intermediate signal intensity on both T1- and T2-weighted images, with a blooming artifact on gradient-echo sequences due to hemosiderin deposition; (ii) the possibility of D-TSGCT—extensive involvement of the synovial membrane with infiltrative margin; and (iii) the resectability and extent—if resectable, synovectomy is performed; if not, a novel systemic therapy involving colony-stimulating factor 1 receptor inhibitors is administered. In the interpretation of follow-up MRIs of D-TSGCTs after treatment, it is crucial to consider both tumor recurrence and potential complications such as osteoarthritis after surgery as well as the treatment response after systemic treatment. Given its prevalence in young adult patents and significant impact on patients’ quality of life, clinical trials exploring new agents targeting D-TSGCT are currently underway. Consequently, understanding the characteristic MRI findings of D-TSGCT before and after treatment is imperative.
腱鞘巨细胞瘤是一种罕见的软组织肿瘤，累及关节、滑囊和腱鞘的滑膜组织，主要影响年轻患者（通常为30-40岁）。该肿瘤包含两种亚型：局限型与弥漫型。尽管这两种亚型在组织学和遗传学上具有相似性，但其预后存在差异。与局限型相比，弥漫型往往表现出更强的局部侵袭性和更高的复发率。磁共振成像是初步诊断和治疗规划的首选诊断工具。在解读疑似腱鞘巨细胞瘤的初次磁共振影像时，必须考虑以下要点：（1）腱鞘巨细胞瘤的特征性表现——T1加权像和T2加权像均呈中低信号强度，梯度回波序列因含铁血黄素沉积出现"开花伪影"；（2）弥漫型的可能性——滑膜广泛受累伴浸润性边缘；（3）可切除性及范围评估——若可切除则行滑膜切除术；若不可切除，则采用新型全身治疗方案，即集落刺激因子1受体抑制剂治疗。在解读弥漫型腱鞘巨细胞瘤治疗后的随访磁共振影像时，必须同时评估肿瘤复发、术后潜在并发症（如骨关节炎）以及全身治疗后的治疗反应。鉴于该疾病在青年患者中的高发性及其对生活质量的显著影响，目前针对弥漫型腱鞘巨细胞瘤靶向新药的临床试验正在进行中。因此，掌握治疗前后弥漫型腱鞘巨细胞瘤的特征性磁共振影像表现至关重要。
肿瘤(癌症)患者之家