Department of Pathology, Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287, USA.
Cancer Cytopathol. 2010 Apr 25;118(2):83-9. doi: 10.1002/cncy.20069.
Malignant solitary fibrous tumors (SFTs) are extremely uncommon and poorly understood mesenchymal neoplasms. There are only rare published accounts of the cytopathologic features of these tumors, prompting the current study.
All cases of malignant SFT with preoperative fine-needle aspirations (FNAs) from 1999 to 2008 were retrieved from the archives of 3 large teaching hospitals. FNA smears and cell block material including immunoperoxidase stains were reviewed, and the cytologic characteristics were described.
Thirteen cases of malignant SFT were identified in 11 patients. Mean age was 58 years, with a men:women ratio of 1:2.6. The tumors were generally large, with a mean size of 13.4 cm. Cytomorphologic features included mostly hypercellular smears with tissue fragments of monotonous, plump spindled cells with blunt-ended and indented nuclei and fragile, wispy cytoplasm. Also seen were bare nuclei, occasional mitoses, and rare necrosis. Some cases showed a predominance of epithelioid cells, whereas others displayed a loose myxomatous matrix. There was a general lack of single cells. None of the cases was diagnosed accurately as malignant SFT on FNA, and only 6 cases were called malignant or suspicious for malignancy.
The FNA diagnosis of malignant SFT is extremely difficult and needs histologic material for accurate interpretation. Predominant FNA diagnoses were SFT or spindle cell neoplasm. Malignant SFT must be included in the differential diagnosis of a spindle cell neoplasm of any anatomic site, particularly if it displays features not typical of benign SFT. Immunoperoxidase staining has some utility, mainly in ruling out other neoplasms in the differential diagnosis.
恶性孤立性纤维瘤（SFT）是非常罕见且尚未被充分了解的间叶性肿瘤。仅有少数关于这些肿瘤细胞病理学特征的文献报道，因此进行了本次研究。
从 3 家大型教学医院的档案中检索了 1999 年至 2008 年所有术前细针抽吸（FNA）的恶性 SFT 病例。对 FNA 涂片和细胞块材料（包括免疫过氧化物酶染色）进行了复习，并描述了细胞学特征。
在 11 名患者中发现了 13 例恶性 SFT。平均年龄为 58 岁，男女比例为 1:2.6。肿瘤通常较大，平均大小为 13.4cm。细胞形态学特征包括大多数呈细胞丰富的涂片，伴有组织碎片的单调、饱满的梭形细胞，细胞核钝圆且有切迹，细胞质脆弱、呈丝状。还可见裸核、偶尔有丝分裂和罕见的坏死。一些病例以上皮样细胞为主，而另一些则显示疏松的黏液样基质。普遍缺乏单个细胞。在 FNA 上，没有一个病例被准确诊断为恶性 SFT，只有 6 个病例被称为恶性或疑似恶性。
恶性 SFT 的 FNA 诊断极为困难，需要组织学材料才能准确解读。主要的 FNA 诊断是 SFT 或梭形细胞肿瘤。恶性 SFT 必须纳入任何解剖部位的梭形细胞肿瘤的鉴别诊断，特别是如果其表现出非典型良性 SFT 的特征。免疫过氧化物酶染色具有一定的作用，主要用于排除鉴别诊断中的其他肿瘤。
