Lynch Michael C, Samson Thomas D, Zaenglein Andrea L, Chung Catherine G
*Department of Pathology, West Virginia University, Morgantown, WV; and Departments of †Plastic Surgery, ‡Dermatology, §Pediatrics, and ¶Pathology, The Penn State Hershey Medical Center, Hershey, PA.
Am J Dermatopathol. 2017 Mar;39(3):225-227. doi: 10.1097/DAD.0000000000000726.
Fibroblastic connective tissue nevus (FCTN) is a rare and recently described neoplasm of fibroblastic/myofibroblastic lineage. We report a case of a 1-month-old healthy male infant who presented with a dermal plaque on the upper chest since birth. A punch biopsy demonstrated a dermal spindle-cell neoplasm with variable smooth muscle actin positivity and negative staining for CD34, consistent with myofibroma. Over the course of the next year, the remaining lesional tissue exhibited clinical softening and a surgical excisional specimen revealed histologic findings distinct from the original biopsy. These included a poorly circumscribed proliferation of bland spindle cells arranged in short fascicles centered in the dermis and extending into the subcutis with positivity for CD34, and absence of staining with smooth muscle actin features diagnostic of FCTN. Our case allowed the opportunity to see this unusual neoplasm at different stages, and we hypothesize that FCTN may undergo an early cellular phase and that time is required for these lesions to "mature" and demonstrate the more characteristic features of FCTN.
纤维母细胞性结缔组织痣（FCTN）是一种罕见的、最近才被描述的纤维母细胞/肌纤维母细胞谱系肿瘤。我们报告一例1个月大的健康男婴，自出生以来上胸部就有一个皮肤斑块。穿刺活检显示为真皮梭形细胞瘤，平滑肌肌动蛋白呈不同程度阳性，CD34染色阴性，符合肌纤维瘤。在接下来的一年里，剩余的病变组织出现临床软化，手术切除标本的组织学表现与最初活检不同。这些表现包括境界不清的温和梭形细胞增生，呈短束状排列，位于真皮中央并延伸至皮下，CD34阳性，平滑肌肌动蛋白染色阴性，这些特征可诊断为FCTN。我们的病例让我们有机会观察到这种不寻常肿瘤的不同阶段，我们推测FCTN可能经历一个早期细胞阶段，这些病变需要时间“成熟”并表现出FCTN更具特征性的表现。
