放射学和肿瘤学杂志

ISSN:2573-7724

Research Article

磁共振成像的诊断精度可区分良性和恶性腮腺肿瘤

萨迪亚·阿里¹, Adeena Khan^2*，基兰·萨法拉兹（Kiran Sarfaraz）³, Saba Akram⁴，Mariam Javaid⁵和Asma Bano⁶

¹FCPS放射学Avicenna医学院和巴基斯坦医院
²FCPS，FRCR，MMED，沙特阿拉伯王国Abdul Aziz大学医院国王
³FCPS Radiology, Lahore General Hospital, Pakistan
⁴FCPS Radiology, Avicenna Medical College and Hospital, Pakistan
⁵FCPS Radiology, Avicenna Medical College and Hospital, Pakistan
⁶FCPS放射学，Bugshan医院，吉达，沙特阿拉伯王国

*通讯地址：Dr. Adeena Khan, FCPS, FRCR, MMED, King Abdul Aziz University Hospital, Kingdom of Saudi Arabia, Tel: 00966-599720990; Email: khan.adeena@yahoo.com

Dates:提交：2018年10月9日;Approved:2018年11月6日;发布：2018年11月7日

How to cite this article:Ali S，Khan A，Sarfaraz K，Akram S，Javaid M等。磁共振成像以区分良性和恶性腮腺肿瘤的诊断精度。J radiol Oncol。2018;2：080-086。doi：10.29328/journal.jro.1001026

版权许可证：©2018 Ali S等。这是根据Creativ必威体育西汉姆联e Commons归因许可分发的开放访问文章，该文章允许在任何媒介中不受限制地使用，分发和复制，前提是适当地引用了原始作品。

关键字：Magnetic resonance imaging; Parotid gland tumours; Diagnostic accuracy; Histopathology

唾液腺肿瘤占所有头颈肿瘤的3％。在腮腺肿瘤中占80％。女性与男性比例为1.04：1，平均年龄为47岁。这些肿瘤的全球发病率每年为每100,000次0.4-13.5 [1-5]。

20–25% of the parotid gland tumors are malignant, while 40% are of submandibular glands and more than 90% are of sublingual glands [6-8]. Out of benign tumors pleomorphic adenoma is the most frequent (83%) followed by Warthins tumor. Amongst malignant tumours, mucoepidermoid carcinoma (49.3%) followed by adenoid cystic carcinoma (31.3%) are common. Parotid swelling for years is the main feature of benign, whereas malignant tumors present with pain, fixation to skin and underlying structures, cervical lymphadenopathy and facial palsy [9-11].

已经使用了几项诊断测试，包括细针抽吸细胞学（FNA）和成像方式，已被用来回答腮腺质量的良性或恶性特性，但磁共振成像（MRI）被认为是一种非侵入性方式，并且针对其他成像方式具有很高的精度像超声检查和CT扫描[12]。它提供了有关病变确切定位的信息，其程度，与邻近结构的关系，周围的传播，骨骼侵袭甚至脑膜浸润[13]。预测恶性肿瘤的特定符号是T2加权图像上的肿瘤高压，不确定的边缘，扩散生长，浸润到皮下组织和淋巴结肿大。在其中，高压和不确定的边缘强烈暗示了恶性肿瘤[14]。磁共振成像的附加优势是向后静脉的可见性，因此区分腮腺的浅层和深叶，这对于选择手术程序很重要[15]。这些解剖学细节很重要，因为对良性腮腺肿瘤的治疗是浅核切除术，而对恶性肿瘤进行了或没有面部神经去除的总甲状腺切除术[16]。

To best of our knowledge no local study is available till now and the international studies that have done so far shown a great variability in results. The purpose of this study was to assess the diagnostic accuracy of Magnetic resonance imaging through subjective analysis of the parotid masses imaging features to differentiate benign and malignant parotid gland tumours, so as to consider it valuable, non invasive, safe and convenient modality for early detection, surgical planning and thus obviate the role of biopsy.

A Cross-sectional study was conducted at the Radiology Department of Lahore General Hospital, Lahore from January till July 2014. Total of 200 patients were included in the study having age ranging from 5 to 80 years, of either gender, had previously diagnosed parotid gland tumour on imaging (ultrasound or CT) or having clinical suspicion of parotid gland tumours such as parotid swelling, fixation to underlying skin and subcutaneous tissue, pain, facial palsy and cervical lymphadenopathy. Patients having contraindication to MRI, post-operative parotid gland tumours, residual or recurrent tumours and those who do not give consent were excluded from the study.

所有患者都征得知情同意。人口特征，即年龄和性别。然后，使用标准成像线圈在1.5-T Philips全体MR系统上进行MRI。获得了T2加权，在轴向，矢状和冠状投影中均具有未增强和对比度增强的T1加权图像。图像解释是由单个放射科医生在高级放射科医生的监督下进行的。MRI诊断，即记录或不存在腮腺肿瘤，并为所有病例进行活检（FNAB）。肿瘤表现出不确定的边缘，浸润到相邻组织，T2上的高压和淋巴结肿大的肿瘤被诊断为恶性。然后记录组织病理学结果。然后比较MRI和组织病理学的结果将组织病理学作为金标准。

使用SPSS版本16分析了收集的数据。对于定量数据，例如年龄，平均值和标准偏差。对于定性数据，即性别，计算了频率和百分比。使用2 x 2表来计算敏感性，特异性，阳性预测值，负预测值和MRI对腮腺肿瘤的MRI准确性，以组织病理学为金标准。

在200名患者中，有170名男性和30名女性。男性和女性患者的平均年龄分别为40.27±15.04和40.12±12。15岁。男性最年轻的患者年龄为10岁，女性为15岁，但男女的年龄相同，即80岁。基于MRI成像特征，125例患者被标记为具有良性肿瘤的良性（图1），而组织病理学发现诊断为121个嗜酸性肿瘤为良性肿瘤，为79为恶性肿瘤（图2）。在MRI和组织病理学上，在两种方式上，将113例患者诊断为良性，有67例患有恶性腮腺肿瘤的患者（图1）。共有20例患者矛盾的结果，其中12例患者被诊断为MRI良性，但在组织病理学上是恶性的。同样，有8例患者被诊断为在MRI上患有恶性肿瘤，但在组织病理学上发现它们具有良性特征（表1）。MRI的敏感性，特异性，正和阴性预测值分别为90.4％，89.33％，93.39％和84.41％。MRI的总体诊断准确性被发现为90％，同时将组织病理学作为金标准。

Although majority of the parotid gland tumours are benign but still it is of major importance to determine non invasive imaging method to distinguish between benign or malignant parotid gland tumours and their anatomical extent preoperatively, because it primarily influence the choice of surgical procedure i.e. superficial versus total parotidectomy [16,17].

据报道，细针吸入活检（FNAB）在区分某些特定的良性和恶性肿瘤分类方面不可靠，并且容易诊断误差[18-20]。MRI在其无创性，缺乏辐射危害，出色的软组织分辨率以及可能更有前途的成像序列（如扩散加权和动态对比度增强的MRI）方面具有优势[17,21-25]。

在我们的研究中，我们推断出，MRI可以洞悉腮腺肿瘤的良性和恶性特征，这是由于其高特异性和准确性。它不仅建立诊断，而且有助于评估临床上可疑的腮腺病变。发现其诊断精度为90％，与以前的文献中发现的FNAB相当[19]。

该研究是针对200名患者进行的，据我们所知，这是迄今为止针对唾液腺肿瘤MRI进行的不同研究所采取的最大样本量。由于在我们的研究中包括5岁及以前的儿童，年龄范围是可变的。最年轻的患者是10岁，长80岁，平均年龄为40岁。这些结果与最新的可用研究相当，在该研究中，他们发现年龄在9至85岁之间，中位年龄在56岁之间。14我们的研究还加强了国际公认的观点，即良性腮腺肿瘤比恶性肿瘤更为普遍，并且该观点是恶性肿瘤的腺体肿瘤没有明显的性偏见[14,26,27]。

Although variable results have been found in the international literature but overall our results are comparable to most of them. Bartels S. and colleagues retrospectively selected forty-eight patients of parotid tumors of any histology out of five hundred and eighty six (13 investigated with CT, 35 with MRI); 23 (48%) of the lesions were malignant and 25 (52%) were benign. MRI, CT, and FNA misclassified 17%, 46%, and 21% of the lesions respectively, indicating MRI being the least contributor in misdiagnosis thus comparable to our results which showed MRI misinterpreting 10 % of the patients. Sensitivity, specificity and accuracy for detecting malignant lesions on MRI and FNA were as follows: MRI (88%, 77%, 83%) and FNA (83%, 86%, 85%) respectively. The investigators concluded that imaging and FNA are comparable in their ability to correctly identify malignant parotid lesions preoperatively and that combining the two modalities yields no advantage in terms of sensitivity, specificity, and accuracy of a malignant tumor diagnosis. The results also added that MRI is the first test of choice, because it was not only as effective as FNAB at labeling the suspicion of malignancy but also provide detailed anatomical information about the extent of the primary tumor and adjacent lymph nodes [28].

Claudia Rudack et al. included 109 patients out of 582 who underwent CT or MRI and reported that MRI investigation has a sensitivity of 98%, a specificity of 52% and an accuracy of 84% [29].

Inohara H等。进行了回顾性研究，并接受了术前接受FNAC和MRI的81例腮腺肿块病变（60个良性和21个恶性病）。他们发现MRI对分化良性和恶性腮腺质量病变的敏感性，特异性和准确性分别为81％，92％，89％。他们得出的结论是，FNAC或MRI同样可以预测腮腺肿块病变的恶性特性，而FNAC和MRI的组合均不在任何一种模态上产生诊断优势[26]。这些值与我们的结果相当（分别为90.4％，89.33％和90％），但我们发现MRI比本研究更敏感。

另一项研究纳入了29例手术腮腺肿瘤患者。他们进行了传统的以及MRI的扩散加权序列，并计算了这些MRI序列的有效性，专门针对恶性肿瘤的诊断。该检查对诊断恶性肿瘤的敏感性远低于我们的结果和以前的研究，即90.4％和57％[27]。小样本量可以解释为这项研究的局限性。

H. Yerli等人在评估肿瘤恶性肿瘤时发现MRI为80％敏感，100％特异性和96％精度。他们在研究中纳入了25个腮腺肿块。他们还从发现常规MRI与DWI相似的诊断潜力[30]中得出。

假阳性诊断时，在检测出恶性腮腺肿瘤的存在时可能会导致更激进的手术，涉及可能实际上不需要淋巴结清除的患者的风险更大。因此，术前评估有助于避免进取的手术计划以及不必要的炎症性手术以及面部神经损伤的可能风险[13]。在我们的研究中，根据MRI发现进行了8个假阳性诊断。具有压缩行为和/或囊性病变的笨重质量（超过5厘米）被解释为MRI上的可疑，在组织病理学上的炎症性病变，囊性多膜腺瘤和沃思蛋白肿瘤中变成了可疑。这些误差可能是由于肿瘤的大尺寸导致其与邻近结构和坏死的关系的误解。

假阴性诊断，评估恶性肿瘤可能会导致实际面临淋巴结转移风险的患者的保守手术治疗（无淋巴结清扫术的表面核切除术）[13]。在我们的研究中，在评估MRI发现后做出了12个假阴性诊断。由于小尺寸（小于5 cm），良好的边缘和狭窄的性质，它们被误解为良性，这些自然是在组织分析中被诊断为低级粘膜外皮样癌，外多态性癌，激素细胞癌和单身转移。这意味着，分阶段错误可能不仅被认为归因于技术的空间分辨率不足，而且还归因于主观的解释错误。在这里，我们还必须牢记，低年级恶性肿瘤也可以具有有或没有囊性成分的有或没有囊性成分的边缘，并且应该在模棱两可的情况下建议患者进行FNA。

This study was not free from limitations. Only qualitative analysis of MRI was done which can generate a subjective error. Single radiologist under one supervisor interpreted the results and interobserver variability was not assessed. Although the patients included in the study were good in number but they were taken only from one tertiary care hospital and might not represent the general population.

In some studies, modern MR techniques such as Dynamic contrast enhanced MRI, Diffusion weighted MRI and MR spectroscopy have already shown promising results in depicting effectively the histological features [13,24,31,32]. So further research on larger scale from different set ups on all MR methods need to be carried out.

MRIhas a potential role in characterization and differentiation between benign and malignant tumours of the parotid glands. It can be used as a promising non invasive diagnostic modality for pre-operative evaluation, accurate staging, proper surgical and therapeutic plan of salivary gland tumours, thus avoiding unnecessary biopsy/FNAC. Sensitivity, specificity, positive and negative predictive value of MRI was 90.4%, 89.33%, 93.39% and 84.41% respectively. The overall diagnostic accuracy of MRI was found to be 90% while taking results of histopathology as a gold standard.