Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
Hum Pathol. 2012 Sep;43(9):1418-24. doi: 10.1016/j.humpath.2011.11.002. Epub 2012 Mar 8.
The morphologic changes seen in desmoid-type fibromatosis after radiotherapy have not been well studied, and the degree of cytologic atypia, cellularity, mitotic activity, and lesional necrosis found in desmoid-type fibromatosis treated with ionizing radiation has not been thoroughly assessed. Therefore, we evaluated a series of primary and locally recurrent desmoid-type fibromatoses resected at variable intervals after radiation therapy (XRT) and compared their histopathologic and immunophenotypic features with paired pathologic specimens that were obtained before radiotherapy. The morphologic characteristics of desmoid-type fibromatoses resected before and after radiotherapy were not significantly different in 7 of the 8 cases studied. One case resected 191 months after XRT showed morphologic evidence of fibrosarcomatous transformation, with zonal necrosis, hypercellularity, severe nuclear atypia, and increased mitotic activity. No significant differences in the immunophenotype of desmoid-type fibromatosis were observed after XRT. In rare cases of recurrent desmoid-type fibromatosis, the differential diagnosis may include radiation-induced fibrosarcoma. Our data suggest that histomorphologic alterations attributable to the effects of ionizing radiation in desmoid-type fibromatosis are minimal. Therefore, the presence of cytologic features of malignancy in this setting warrants careful examination and consideration of the rare occurrence of postradiation sarcoma. Lesser degrees of nuclear atypia seen in isolation do not necessarily indicate a poor prognosis in irradiated desmoid-type fibromatosis.
放疗后硬纤维瘤样纤维瘤病的形态变化尚未得到很好的研究，并且用电离辐射治疗的硬纤维瘤样纤维瘤病中发现的细胞异型性、细胞密度、有丝分裂活性和病变坏死程度尚未得到彻底评估。因此，我们评估了一系列在放射治疗（XRT）后不同时间切除的原发性和局部复发性硬纤维瘤样纤维瘤，并将其组织病理学和免疫表型特征与放射治疗前获得的配对病理标本进行了比较。在研究的 8 例中，有 7 例在 XRT 前后切除的硬纤维瘤样纤维瘤的形态特征没有明显差异。一例在 XRT 后 191 个月切除的病例显示出纤维肉瘤样转化的形态学证据，具有带状坏死、细胞密度增加、严重核异型性和有丝分裂活性增加。XRT 后硬纤维瘤样纤维瘤的免疫表型无明显差异。在罕见的复发性硬纤维瘤样纤维瘤的情况下，鉴别诊断可能包括放射诱导的纤维肉瘤。我们的数据表明，硬纤维瘤样纤维瘤病中归因于电离辐射作用的组织形态学改变很小。因此，在这种情况下出现恶性细胞特征需要仔细检查，并考虑罕见的放射后肉瘤。孤立存在的较轻程度的核异型性不一定表明放射治疗的硬纤维瘤样纤维瘤预后不良。
