鼻腔鼻窦原发恶性黑色素瘤影像学误诊分析并文献回顾

Imaging Misdiagnosis Analysis and Literature Review of Primary Malignant Melanoma in the Nasal Cavity and Sinuses

目的探讨鼻腔鼻窦原发恶性黑色素瘤的影像学特征,以期减少临床误诊。方法回顾性分析2012年1月—2022年12月在福建医科大学附属龙岩第一医院经病理证实6例鼻腔鼻窦原发恶性黑色素瘤的影像学资料,6例均行CT检查,3例行MRI平扫联合增强检查,1例行PET-CT检查。结果CT检查:5例肿瘤发生于单侧,1例跨中线累及对侧;肿瘤位于鼻腔2例,鼻窦1例,同时累及鼻腔鼻窦3例;肿块较大,形态不规则,呈软组织密度,易坏死囊变,其内未见明显钙化,呈轻度至明显不均匀强化。MRI检查:2例呈T1WI等高信号、T2WI等低信号;1例呈T1WI低信号、T2WI稍高信号;增强中度强化;2例病灶内见线条样或分隔样强化。1例行PET-CT检查,肿瘤SUV_(max)12.2,同时检出Ⅱ组1枚稍大淋巴结转移。4例周边骨质呈溶骨性破坏,5例侵犯临近结构。结论鼻腔鼻窦原发恶性黑色素瘤CT表现缺乏特征;黑色素型患者MRI表现有一定特点,T2WI肿瘤内多发纡曲线状低信号影,增强呈线条状或分隔样强化具有提示诊断意义。CT和MRI联合检查应用能较好显示鼻腔鼻窦原发恶性黑色素瘤的部位、范围、周围骨质改变以及与邻近重要结构的关系。

Objective To explore the imaging features of primary malignant melanoma in the nasal cavity and sinuses,in order to reduce clinical misdiagnosis.Methods A retrospective analysis was conducted on the imaging data of six cases of primary malignant melanoma in the nasal cavity and sinuses confirmed by pathology at Longyan First Hospital Affiliated to Fujian Medical University from January 2012 to December 2022.All cases underwent CT examination,three cases underwent MRI plain scan and enhancement,and one case underwent PET-CT.Results CT examination:five cases of tumors occurred on one side,and one case involved the opposite side across the midline.The tumor was located in the nasal cavity in two cases,in the sinuses in one case,and simultaneously involved the nasal cavity and sinuses in three cases.The mass is relatively large,irregularly shaped,with soft tissue density and prone to necrosis and cystic transformation.There is no obvious calcification within it,and it shows mild to significant uneven enhancement.MRI examination:two cases showed high signal intensity on T1WI and low signal intensity on T2WI;One case showed low signal on T1WI and slightly high signal on T2WI;Moderate enhancement;Two cases showed linear or septal enhancement within the lesion.One routine PET-CT examination showed a tumor SUV_(max) was 12.2,and at the same time,one slightly larger lymph node metastasis was detected in Group II.Four cases showed osteolytic destruction of the surrounding bone,and five cases invaded adjacent structures.Conclusion CT manifestations of primary malignant melanoma in the nasal cavity and sinuses lack characteristics.The MRI manifestations of melanin type patients have certain characteristics.On T2WI,there are multiple curved low signal shadows within the tumor,with enhanced linear or septal enhancement,which has diagnostic significance.The combination of CT and MRI can better display the location,extent,surrounding bone changes,and relationship with adjacent important structures of the tumor.