Baehner Frederick L, Ng Brenda, Sudilovsky Daniel
Division of Cytopathology, University of California, San Francisco 94115, USA.
Acta Cytol. 2005 Sep-Oct;49(5):543-8. doi: 10.1159/000326203.
The protean morphology of malignant melanoma is diagnostically challenging. Balloon cell melanoma is a histologic variant composed predominantly or entirely of large cells with abundant, vacuolated cytoplasm. It shares the cytologic features of the other subcategories of malignant melanoma, such as discohesion, nuclear pleomorphism and intranuclear cytoplasmic pseudoinclusions, but generally lacks melanin pigment and, as the name would suggest, is characterized by the presence of numerous cytoplasmic vacuoles.
A 55-year-old man presented with an enlarged right cervical lymph node. Clinically and radiographically this mass was considered to be metastatic; however, the patient had no known primary neoplasm. Fine needle aspiration biopsy (FNAB) and cytologic examination showed numerous discohesive, variably sized, malignant cells with abundant, vacuolated cytoplasm and pleomorphic nuclei with irregular nuclear contours, macronucleoli and frequent intranuclear cytoplasmic pseudoinclusions. Pigment was not identified. These features, along with strong immunohistochemical positivity for S-100, HMB-45 and Melan-A, suggested the diagnosis of balloon cell melanoma. A right parotidectomy and lymph node dissection were performed, and histologic tissue evaluation confirmed the diagnosis.
This case of lymph node balloon cell melanoma metastasis was diagnosed by FNAB.
恶性黑色素瘤多变的形态在诊断上具有挑战性。气球状细胞黑色素瘤是一种组织学变体，主要或完全由具有丰富空泡状细胞质的大细胞组成。它具有恶性黑色素瘤其他亚类的细胞学特征，如细胞间黏附丧失、核多形性和核内胞质假包涵体，但通常缺乏黑色素，顾名思义，其特征是存在大量细胞质空泡。
一名55岁男性因右侧颈部淋巴结肿大就诊。临床和影像学检查认为该肿块为转移性；然而，患者无已知原发性肿瘤。细针穿刺活检（FNAB）及细胞学检查显示大量细胞间黏附丧失、大小不一的恶性细胞，具有丰富的空泡状细胞质和核轮廓不规则、有大核仁及频繁核内胞质假包涵体的多形性核。未发现色素。这些特征，以及S-100、HMB-45和Melan-A的强免疫组化阳性，提示诊断为气球状细胞黑色素瘤。行右侧腮腺切除术及淋巴结清扫术，组织学评估证实了诊断。
该例淋巴结气球状细胞黑色素瘤转移通过FNAB得以诊断。
