Kazan Huseyin Ozgur, Culpan Meftun, Gunduz Nesrin, Keser Ferhat, Iplikci Ayberk, Atis Ramazan Gokhan, Yildirim Asif
Istanbul Medeniyet University, School of Medicine, Department of Urology, Istanbul, Turkey.
Istanbul Medeniyet University, School of Medicine, Department of Radiology, Istanbul, Turkey.
Bladder Cancer. 2022 Mar 11;8(1):35-44. doi: 10.3233/BLC-211535. eCollection 2022.
Inchworm sign is a finding on diffusion-weighted magnetic resonance imaging (DWI-MRI) and is used to better stratify T-staging in muscle invasive (MIBC) and non-muscle-invasive bladder cancer (NMIBC). An uninterrupted low submucosal signal on DWI, defined as inchworm sign (IS), indicates NMIBC.
We aimed to define the diagnostic accuracy of IS in primary bladder cancer, as well as find agreement between the urologists and the radiologist.
Between December 2018 and December 2020, we retrospectively analyzed 95 primary bladder cancer patients who had undergone multiparametric-MRI before transurethral resection. Patients with former bladder cancer history, tumors smaller than 10 mm, and MRI without proper protocol, as well as patients who did not attend follow-up, were excluded. In total, 71 patients' images were evaluated by a genitourinary specialist radiologist and two urologists. Sensitivity, specificity, positive and negative predictive values of IS and VI-RADS in differentiating MIBC and NMIBC, and interreader agreement between the radiologist and urologists were analyzed.
During follow-up, 38 patients (53.5%) were IS-positive, while 33 patients (46.5%) were negative. Among the 33 patients with negative IS, 14 patients (42.4%) had MIBC. Meanwhile, two out of the 38 IS-positive patients (5.3%) had MIBC ( = 0.00). Sensitivity, specificity, and positive and negative predictive values of IS in predicting MIBC were 87.5%, 63.6%, 41.2%and 94.6%, respectively. The interobserver agreement between the urologists and radiologist was almost perfect ( = 0.802 and = 0.745).
The absence of IS on DWI is useful in differentiating MIBC from NMIBC. It is a simple finding that can be interpreted by urologists.
尺蠖征是弥散加权磁共振成像（DWI-MRI）上的一种表现，用于更好地对肌层浸润性膀胱癌（MIBC）和非肌层浸润性膀胱癌（NMIBC）进行T分期。DWI上连续的低黏膜下信号，定义为尺蠖征（IS），提示NMIBC。
我们旨在确定IS在原发性膀胱癌中的诊断准确性，并找出泌尿外科医生和放射科医生之间的一致性。
2018年12月至2020年12月期间，我们回顾性分析了95例经尿道切除术前接受多参数MRI检查的原发性膀胱癌患者。排除有既往膀胱癌病史、肿瘤小于10毫米、MRI检查方案不当以及未进行随访的患者。共有71例患者的图像由一位泌尿生殖系统专科放射科医生和两位泌尿外科医生进行评估。分析了IS和VI-RADS在鉴别MIBC和NMIBC方面的敏感性、特异性、阳性和阴性预测值，以及放射科医生和泌尿外科医生之间的阅片者一致性。
随访期间，38例患者（53.5%）IS阳性，33例患者（46.5%）阴性。在33例IS阴性的患者中，14例（42.4%）患有MIBC。同时，38例IS阳性患者中有2例（5.3%）患有MIBC（P = 0.00）。IS预测MIBC的敏感性、特异性、阳性和阴性预测值分别为87.5%、63.6%、41.2%和94.6%。泌尿外科医生和放射科医生之间的观察者间一致性几乎完美（κ = 0.802和κ = 0.745）。
DWI上无IS有助于鉴别MIBC和NMIBC。这是一个简单的表现，泌尿外科医生可以进行解读。
