Remstein E D, Arndt C A, Nascimento A G
Department of Laboratory Medicine and Pathology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
Am J Surg Pathol. 1999 Jun;23(6):662-70. doi: 10.1097/00000478-199906000-00005.
Twenty-two cases of plexiform fibrohistiocytic tumor were reviewed to perform a clinicopathologic correlation with the behavior of the neoplastic entity. The tumor arises more frequently in children, adolescents, and young adults (mean age of presentation, 14.6 years), with strong female predilection (F:M, 6:1). It involves preferentially the upper extremity (64%), especially the fingers, hand, or wrist (45%). Most patients present with a small (average size, 2.5 cm; range, 0.5-8 cm) painless mass that slowly enlarges for months to years. All tumors involve subcutaneous adipose tissue, with extension into the dermis (19%), skeletal muscle (14%), or both (14%). Grossly, the tumors characteristically are poorly circumscribed and of firm consistency. Histologically, they are characterized by a plexiform proliferation of mononuclear histiocyte-like cells, multinucleated osteoclast-like cells, and spindle fibroblast-like cells in variable proportions and have three distinct growth patterns: fibrohistiocytic (36% of tumors), fibroblastic (32%), and mixed (32%), depending on the predominant cell type. Cellular atypia and pleomorphism are usually absent or minimal. Most tumors (78%) display mitotic activity, frequently <3 mitoses/10 high-power fields, and only 14% of the lesions display atypical mitoses. Vascular invasion was seen in only one tumor. Immunohistochemically, all tumors evaluated reacted with antibodies to CD68 that stained mainly the multinucleated giant cells and, to a lesser extent, mononuclear histiocyte-like cells and, occasionally, fibroblast-like cells. Less frequently, staining with antiactin antibodies was observed, restricted mainly to spindle cells. All nine tumors examined had a diploid DNA content. According to latest follow-up data (average period, 3.6 years) from 16 patients, 13 (82%) were alive with no evidence of disease (average, 3.6 years), 1 (6%) was alive with metastatic disease (follow-up, 2.3 years), 1 (6%) was alive with a stable pulmonary nodule of unknown nature (follow-up, 1.75 years), and 1 (6%) had died of disease 3 years after local recurrence and regional lymph node and pulmonary metastases developed. Two patients (12.5%) had local recurrence, 1 (6%) had regional lymph node metastasis, and 3 (19%) had pulmonary metastases. No proven association between clinicopathologic features and outcome was identified. In conclusion, plexiform fibrohistiocytic tumor is a rare mesenchymal neoplasm of young persons characterized by low-grade malignant behavior and is prone to recur locally and occasionally to metastasize regionally and systemically.
回顾了22例丛状纤维组织细胞瘤病例，以对该肿瘤实体的行为进行临床病理相关性分析。该肿瘤在儿童、青少年和青年中更为常见（平均发病年龄14.6岁），女性明显居多（女∶男为6∶1）。它优先累及上肢（64%），尤其是手指、手部或腕部（45%）。大多数患者表现为一个小的（平均大小2.5 cm；范围0.5 - 8 cm）无痛性肿块，数月至数年缓慢增大。所有肿瘤均累及皮下脂肪组织，可延伸至真皮（19%）、骨骼肌（14%）或两者（14%）。大体上，肿瘤的特征是边界不清，质地坚实。组织学上，其特征是单核组织细胞样细胞、多核破骨细胞样细胞和梭形成纤维细胞样细胞以不同比例呈丛状增生，有三种不同的生长模式：纤维组织细胞型（占肿瘤的36%）、纤维母细胞型（32%）和混合型（32%），取决于主要的细胞类型。通常不存在细胞异型性和多形性，或程度轻微。大多数肿瘤（78%）显示有丝分裂活性，通常每10个高倍视野<3个有丝分裂象，只有14%的病变显示非典型有丝分裂象。仅在1例肿瘤中见到血管侵犯。免疫组化方面，所有评估的肿瘤均与抗CD68抗体反应，主要染色多核巨细胞，其次是单核组织细胞样细胞，偶尔也染色成纤维细胞样细胞。较少见的是，观察到抗肌动蛋白抗体染色，主要限于梭形细胞。所检查的9例肿瘤均为二倍体DNA含量。根据16例患者的最新随访数据（平均随访期3.6年），13例（82%）存活且无疾病证据（平均3.6年），1例（6%）存活但有转移性疾病（随访2.3年），1例（6%）存活且有性质不明的稳定肺结节（随访1.75年），1例（6%）在局部复发、区域淋巴结和肺转移发生3年后死于疾病。2例患者（12.5%）有局部复发；1例（6%）有区域淋巴结转移；3例（19%）有肺转移。未发现临床病理特征与预后之间有确切关联。总之，丛状纤维组织细胞瘤是一种罕见的年轻人间叶性肿瘤，具有低度恶性行为，易于局部复发，偶尔也会发生区域和全身转移。
