体表血管平滑肌瘤及其钙化亚型的临床病理学观察

Clinicopathological features of cutaneous angioleiomyoma and its calcified subtype

目的 探讨体表性血管平滑肌瘤（cutaneous angioleiomyoma,CAL）及其钙化亚型（cutaneous calcified angioleiomyoma,CCAL）的临床病理学特征.方法 对61例CAL（包括4例CCAL）的临床表现、影像学特征及病理学特点进行分析.结果 女性多见,占60.66%（37/61）,就诊年龄10～87岁,平均43.08岁,以20～69岁居多,占85.25%（52/61）.4例CCAL均为女性,平均年龄63.75岁.所有病例中以下肢受累最为多见,占75.41%（46/61）.临床表现为局部真皮深层或皮下缓慢性生长的多于半数伴有疼痛（35/61,57.38%）的孤立性结节,局部皮肤稍隆起,偶尔呈息肉样外观.肿瘤无特征性影像学表现,其显示病变为真皮深层或皮下孤立性结节,少数病变可伴有程度不等的钙化.大体示肿瘤结节质硬,界清,有纤薄的假包膜,直径为0.5～3.5 cm,圆形或卵圆形.镜下肿瘤实质由丰富的血管和增生的平滑肌混合而成.根据主要组织学结构分为3型：实性型、静脉型和海绵型.少数病变可伴发玻璃样变、钙化、黏液样变、脂肪组织增生、淋巴细胞浸润、出血及脉管内血栓机化等改变.CCAL病变中钙化灶呈沙粒状、斑块状或无定型团块状,钙化显著者可占据肿瘤实质的绝大部分区域,仅残留少量难于识别的平滑肌组织.免疫组化检查显示病变组织中平滑肌细胞表达vimentin、desmin、MSA、α-SMA、calponin及caldemon,而HMB45及CD34均阴性.结论 CAL是一种发生于体表的、可有疼痛的良性软组织肿瘤,位于真皮深层或皮下组织内,影像学无特征性改变,形态上主要表现为增生的平滑肌束围绕在血管周围呈肿瘤性的生长.少数病例可伴发程度不等的钙化,诊断时需与肿瘤性钙盐沉积症、钙化上皮瘤、钙化性纤维性假瘤以及其他继发性皮肤钙盐沉积症相鉴别.

Purpose To study the clinicopathological features of cutaneous angioleiomyoma （CAL） including its calcitied subtype, cutaneous calcified angioleiomyoma （CCAL）. Methods 61 cases of CALs including 4 CCALs were investigated with analyses of the clinical manifestations, imaging features and histopathological characteristics. Results Of 61 cases of CALs, 24 were male and 37 were female, age ranged 10 - 87 years with average 43.08 years. 85.25% of them usually occurred between the twentieth and sixth decades, and the mean age of CCALs was considerably older than that of all CALs. 75.41% of all CALs involved the lower extremity. Clinically, CALs presented as a slow-growing, solitary, firm and well-defined neoplasm located in dermis or subcutaneous tissue, occa- sionally emerged as a polypoid mass. One of the typical clinical features of CALs presented in more than half of the patients was pain. The imaging findings were not characteristic, and the tumors showed solitary nodules in the deep dermis or subcutaneous tissue and occasionally associated with varying degrees of calcification. Grossly, CALs usually presented as solitary, firm, round or oval, well-defined nodules with fibrous pseudocapsule covered by normal skin, and their average size was about 0. 5 - 3.5 cm. Microscopically, CALs consisted in well - defined lesions of vascular spaces with varied size and thick muscle walls, containing concentrically arranged smooth muscle cells within the muscular walls and interspersed with collagen fibers between vessels. According to the dominant microscopic pattern, these tumors were divided into three histologie subtypes： solid, cavernous and venous. Additional microscopic changes found in some CALs, included foci of sclerosis, small groups of mature adipocytes, myxoid changes, calcification, lymphocytic infiltra- tion, organized thrombi in the lumen of the vessels and areas of hemorrhage. The presence of calcification in the CCALs was rare and usually scattered to small flecks, sand - like, plaque-like, large mulberry-like calcification. The major areas in some CCALs were dominated by large amounts of calcification with a little of smooth muscle tissues identified. Immunophenotyping showed that smooth muscles were strongly positive for vimentin, desmin, MSA, α-SMA, calponin and caldesmon, and uniformly negative for HMB45 and CD34. Conclusions CALs are benign cutaneous soft tissue tumors usually found in the lower extremities and frequently affect women, more than half of them are associated with pain. CALs present as solitary tumors located in dermis or subcutaneous tissue. The imaging findings are not characteristic. Histopathologically, they are characterized as proliferations of smooth muscle cells intermingled with abundant vascular channels. The presence of calcification within the tumor is rare, but may be found in CCALs. The differential diagnosis of CALs includes some phymatoid lessions with extensive calcification.