Nardi Cosimo, Vignoli Chiara, Vannucchi Margherita, Pietragalla Michele
Department of Experimental and Clinical Biomedical Sciences, Radiodiagnostic Unit n. 2, University of Florence - Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.
Department of Surgery and Translational Medicine, Division of Pathological Anatomy, University of Florence - Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.
BMJ Case Rep. 2019 Jul 22;12(7):e229790. doi: 10.1136/bcr-2019-229790.
A 67-year-old man presented to ear, nose and throat department complaining of nasal congestion and recurrent epistaxis for 5 months. Nasal endoscopy revealed a pigmented polyp obstructing the right nasal cavity. MRI with contrast agent showed a right nasal cavity polypoid mass with hyper signal intensity (SI) both in non-enhanced T1-w and diffusion imaging, marked hypo SI in T2-w sequences and avidly contrast enhancement characterised by rapid wash-in without significant wash-out on dynamic perfusion imaging. Histological specimen showed epithelioid and spindle cells with focal intense pigmentations and immunohistochemical features compatible with primary melanotic sinonasal mucosal melanoma (SNM). As melanotic SNM shows MRI pathognomonic high non-enhanced T1-w SI, this case underlines the crucial role of MRI not only in assessing the local tumour extension/recurrence but also in increasing the diagnostic confidence of detecting melanotic SNM. Thus, MRI should be always performed in case of clinical-endoscopic suspicion of SNM.
一名67岁男性因鼻塞和反复鼻出血5个月就诊于耳鼻喉科。鼻内镜检查发现一个色素沉着息肉阻塞右侧鼻腔。增强磁共振成像（MRI）显示右侧鼻腔有一个息肉样肿物，在非增强T1加权像和扩散成像上均呈高信号强度（SI），在T2加权序列上呈明显低信号，动态灌注成像显示快速强化且无明显廓清。组织学标本显示上皮样细胞和梭形细胞，有局灶性强烈色素沉着，免疫组化特征符合原发性鼻窦黏膜黑色素瘤（SNM）。由于黑色素性SNM在MRI上表现为具有诊断特征性的高非增强T1加权SI，该病例强调了MRI不仅在评估局部肿瘤扩展/复发方面，而且在提高检测黑色素性SNM的诊断信心方面的关键作用。因此，对于临床内镜怀疑为SNM的病例，应始终进行MRI检查。
