Schwannomas of the sinonasal tract and nasopharynx.
Schwannomas of the sinonasal tract and nasopharynx.
复制标题
鼻窦和鼻咽神经鞘瘤。
作者：
S. Hasegawa;T. Mentzel;C. Fletcher
大约 45% 的良性周围神经鞘肿瘤发生在头颈部区域。其中，源自鼻腔和鼻旁窦的神经鞘瘤（神经鞘瘤）占不到4%。该子集的病理特征尚未得到充分记录。我们报告了五例鼻窦神经鞘瘤病例和一例鼻咽部病例。男女比例相等，就诊年龄范围为 38 至 65 岁（中位年龄 52 岁）。其中4个病变位于鼻腔内，1个起源于上颌窦，1个起源于鼻咽部，并延伸至咽鼓管。 2例表现为局部骨质破坏，并有颅内扩展。临床症状包括鼻塞、鼻衄、鼻漏、嗅觉丧失、面部肿胀、头痛、浆液性中耳炎；两例颅内扩散病例还出现视力障碍。 6例均采用手术切除治疗。 5 例患者的临床随访时间为 6 至 48 个月（中位时间为 27 个月）。在组织学上，所有病变都具有许多与其他部位出现的神经鞘瘤常见的细胞形态学特征，并且所有 6 个病例均显示出对 S-100 蛋白的强烈、弥漫性免疫反应性。 4 例显示细胞变异的特征，1 例显示局灶性颗粒细胞变化。与大多数其他解剖部位出现的神经鞘瘤不同，一种不寻常且先前记录很少的组织学特征是缺乏包膜，当与细胞增多相结合时，常常会引起恶性肿瘤的怀疑。由于该系列中的病例迄今为止尚未显示出局部复发或术后转移，因此在该部位出现的组织学上典型的神经鞘瘤中缺乏包膜和局部破坏性生长不应表明有恶性潜力。
Approximately 45% of benign peripheral nerve sheath tumors occur in the head and neck region. Of these, schwannomas (neurilemomas) arising from the nasal cavity and paranasal sinuses account for less than 4%. Pathologic features of this subset are not well documented. We report a series of five cases of sinonasal schwannoma and one in the nasopharynx. The male-to-female ratio was equal, and the age at presentation ranged from 38 to 65 years of age (median, 52 yr). Four of the lesions were located within the nasal cavity, one arose from the maxillary sinus, and one originated in the nasopharynx, with extension into the Eustachian tube. Two cases showed local bony destruction, with intracranial extension. Presenting clinical symptoms included nasal obstruction, epistaxis, rhinorrhea, anosmia, facial swelling, headache, and serous otitis media; the two cases with intracranial spread also presented with visual disturbances. All of the six cases were treated by surgical excision. Clinical follow-up in five cases ranged from 6 to 48 months (median, 27 mo). Histologically, all of the lesions shared many cytomorphologic features common to schwannomas arising at other sites, and all of the six cases showed strong, diffuse immunoreactivity for S-100 protein. Four cases showed features of the cellular variant, and one showed focal granular cell change. An unusual and previously poorly documented histologic feature, distinct from schwannomas arising at most other anatomic sites, was a lack of encapsulation, which, when combined with hypercellularity, often raised suspicion of malignancy. Because none of the cases in this series has shown either local recurrence or postoperative metastasis to date, lack of encapsulation and locally destructive growth in an otherwise histologically typical schwannoma arising at this site should not suggest malignant potential.