Department of Plastic and Reconstructive Surgery, Nippon Medical School Musashi-Kosugi Hospital, Kawasaki, Kanagawa, Japan.
Department of Dermatology, Nippon Medical School Musashi-Kosugi Hospital, Kawasaki, Kanagawa, Japan.
J Dermatol. 2023 Apr;50(4):485-493. doi: 10.1111/1346-8138.16638. Epub 2022 Nov 14.
Dermatofibroma is a common benign skin lesion with a contested etiology: some believe it is a neoplasm while others propose minor injuries initiate it. Many dermatofibroma variants have been described, including keloidal dermatofibroma, which is unusual by bearing keloidal collagen. Keloidal dermatofibroma was first described in 1998 and only 15 cases have been reported. Since keloids are driven by skin injuries, the existence of keloidal dermatofibroma has been suggested to support the injury hypothesis of dermatofibroma etiology. To better understand keloidal dermatofibroma characteristics and gain clues regarding dermatofibroma etiology, consecutive keloidal dermatofibroma cases (n = 52) and dermatofibroma without keloidal collagen (n = 2077) that were histopathologically diagnosed in 2016-2019 were identified from the records of a Japanese dermatopathology laboratory and compared in terms of demographic, clinical, and histopathological characteristics by univariate analyses. Compared to other dermatofibromas, keloidal dermatofibromas occurred more frequently on the forearm and hand (P < 0.0001 and 0.0019), especially the wrist dorsum, and in the superficial skin layer (P < 0.0001). Keloidal dermatofibromas also demonstrated more cellularity and hemorrhage (both P < 0.0001). Correlation analyses between keloidal collagen amount and keloidal dermatofibroma size (a proxy of time-since-onset) did not support the notion that keloidal collagen deposition and keloidal dermatofibroma formation are triggered simultaneously. Recent injury, as indicated by fresh hemorrhage, was equally common in putatively older and younger keloidal dermatofibromas. Thus, keloidal collagen in keloidal dermatofibromas could be due to injury to preexisting dermatofibromas, which suggests that the keloidal dermatofibroma entity does not prove the injury hypothesis. Commonalities between keloids and keloidal dermatofibromas suggest a link between genetics, provocative events that induce myofibroblast differentiation, and keloidal collagen production.
隆突性皮肤纤维肉瘤是一种常见的良性皮肤病变，其病因存在争议：一些人认为它是一种肿瘤，而另一些人则认为轻微损伤会引发它。已经描述了许多隆突性皮肤纤维肉瘤的变体，包括瘢痕疙瘩样隆突性皮肤纤维肉瘤，其特征是具有瘢痕疙瘩样胶原。瘢痕疙瘩样隆突性皮肤纤维肉瘤于 1998 年首次描述，仅报道了 15 例。由于瘢痕疙瘩是由皮肤损伤引起的，因此瘢痕疙瘩样隆突性皮肤纤维肉瘤的存在支持了隆突性皮肤纤维肉瘤病因的损伤假说。为了更好地了解瘢痕疙瘩样隆突性皮肤纤维肉瘤的特征，并获得关于隆突性皮肤纤维肉瘤病因的线索，从日本皮肤科病理实验室的记录中确定了 2016-2019 年间病理诊断为瘢痕疙瘩样隆突性皮肤纤维肉瘤（n=52）和无瘢痕疙瘩样胶原的隆突性皮肤纤维肉瘤（n=2077）的连续病例，并通过单变量分析比较了它们的人口统计学、临床和组织病理学特征。与其他隆突性皮肤纤维肉瘤相比，瘢痕疙瘩样隆突性皮肤纤维肉瘤更常发生在前臂和手部（P<0.0001 和 0.0019），尤其是手腕背侧和浅层皮肤层（P<0.0001）。瘢痕疙瘩样隆突性皮肤纤维肉瘤也表现出更多的细胞性和出血性（均 P<0.0001）。瘢痕疙瘩样胶原量与瘢痕疙瘩样隆突性皮肤纤维肉瘤大小（发病时间的代理）之间的相关性分析不支持瘢痕疙瘩样胶原沉积和瘢痕疙瘩样隆突性皮肤纤维肉瘤形成同时触发的观点。如新鲜出血所示的近期损伤在推测年龄较大和较小的瘢痕疙瘩样隆突性皮肤纤维肉瘤中同样常见。因此，瘢痕疙瘩样隆突性皮肤纤维肉瘤中的瘢痕疙瘩样胶原可能是由于对先前存在的隆突性皮肤纤维肉瘤的损伤所致，这表明瘢痕疙瘩样隆突性皮肤纤维肉瘤实体并不能证明损伤假说。瘢痕疙瘩和瘢痕疙瘩样隆突性皮肤纤维肉瘤之间的共性表明遗传因素、诱导成肌纤维细胞分化的诱发事件和瘢痕疙瘩样胶原产生之间存在联系。
