A case of cutaneous symplastic leiomyoma - a rare variant of cutaneous pilar leiomyoma

We describe the case of a cutaneous symplastic leiomyoma in a 37-year-old woman who presented with a 4-year history of a painful slow growing lesion on the left upper arm. The lesion was excised and subjected to histological examination. A poorly circumscribed lesion was seen in the dermis composed of spindle shaped cells with marked nuclear pleomorphism. No mitotic figures or necrosis were seen. The cells stained strongly positive with desmin and smooth muscle actin, and negative with S100, melan A, MNF116 a mouse monoclonal antibody to cytokeratin and CK5/6. The diagnosis was felt to be in keeping with a cutaneous symplastic leiomyoma, a rarely reported variant of the pilar leiomyoma. Histologically, it shows features similar to the symplastic variant of uterine leiomyoma with cytological atypia, nuclear pleomorphism and minimal mitotic activity. Although the long-term outlook is probably benign, the presence of cytological atypia and mitoses in any spindle cell tumor is generally a concerning feature and warrants long-term follow up.     

Ossified soft tissue leiomyoma in a patient with sickle cell anemia

Osseous metaplasia in leiomyomas is extremely rare. Here, we report the case of an ossified subcutaneous leiomyoma in a 34-year-old African American man with sickle cell thalassemia who presented with a painful nodule of the scapular region, which appeared as a heavily mineralized soft tissue mass on chest radiographs. Histopathologic and immunohistochemical examination of the resected nodule revealed a benign soft tissue leiomyoma composed of intersecting fascicles of spindle cells that strongly expressed smooth muscle actin and caldesmon. Extensive intratumoral calcification and ossification were noticed. Only eight cases of ossified leiomyoma have been reported, of which two arose in the deep soft tissue.     

Hyperkeratotic lesion of the nipple revealing cutaneous leiomyoma

BACKGROUND: Leiomyoma of the nipple and areola is a rare benign neoplasm. We report the case of a patient with leiomyoma of the nipple presenting as a hyperkeratotic plaque. OBSERVATION: A 23-year-old patient presented with a five year history of a papillomatous, hyperkeratotic, painful plaque originating in her right nipple. Histological examination of a punch biopsy showed hyperkeratosis of the epidermis with dilatation of the lymphatic vessels within the dermis. Surgical excision revealed a proliferation of smooth muscle fibres, leading to diagnosis of leiomyoma. DISCUSSION: The clinical and histological features were initially consistent with idiopathic naevoid hyperkeratosis of areola. However, associated pain is uncommon in idiopathic lesions. This unusual feature led us to surgical excision enabling the diagnosis of leiomyoma. A hyperkeratotic lesion of the nipple may be associated with benign or malignant neoplasms, hamartoma or chronic dermatoses, or it may be idiopathic. In the present case, the hyperkeratotic lesion revealed subareolar leiomyoma. This is an uncommon clinical presentation not previously seen in medical observations, since leiomyoma usually presents as a firm, painful lump in the subareolar region.     

Dermatomyofibroma (Plaqueförmige Dermale Fibromatose)

We reported a patient with dermatomyofibroma and reviewed the literature to characterize the immunohistochemical features of dermatomyofibroma. A 25-year-old woman presented with an asymptomatic, well-circumscribed, red-brown plaque on the left posterior shoulder. Microscopic examination revealed a non-encapsulated but well-circumscribed tumor in the mid-dermis extending into the upper subcutaneous fatty tissue. The tumor was composed of faintly eosinophilic, thin, wavy collagen fibers arranged as intersecting fascicles with an arrangement predominantly parallel to the skin surface. Embedded among the wavy fibers, there were a fair number of nuclei that were elongated, vesicular, and uniform in size. Immunohistochemical studies using a peroxidase-antiperoxidase technique disclosed that the cytoplasm of the tumor cells was positive for muscle actin. The tumor cells were negative for α-smooth muscle actin, desmin, factor XIIIa, S-100 protein, and CD34. Clinical, histopathologic, and immunohistochemical analysis confirmed dermatomyofibroma.     

Cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma: a rare occurrence and potential diagnostic pitfall

A case of cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma is described. The patient was a 60‐year‐old man who presented with a painless nodule on his chest. Thorough clinical examination did not reveal any evidence of tumor elsewhere. A punch biopsy was performed which showed a benign spindle cell neoplasm with focal cellular pleomorphism that had smooth muscle differentiation and was clearly originating from the arrector pili muscle, consistent with a cutaneous symplastic pilar leiomyoma. Immunohistochemical studies were performed and the tumor cells were strongly positive for smooth muscle actin (SMA) and desmin. Given the clinical information of a mass on the chest, clinical evaluation was recommended and a re‐excision was performed. Histologically, the re‐excision showed two distinct populations of cells. The upper portion of the tumor mirrored the initial biopsy; however, the base of the tumor showed hypercellular areas composed of spindle cells with marked pleomorphism and increased number of mitoses. The diagnosis of a cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma was given. This is the first report of this association of such occurrence reported in the literature. Fons ME, Bachhuber T, Plaza JA. Cutaneous leiomyosarcoma originating in a symplastic pilar leiomyoma: a rare occurrence and potential diagnostic pitfall.     

Intravascular myopericytoma

BACKGROUND: Myopericytoma is a benign tumor composed of cells that show apparent differentiation towards putative perivascular myoid cells called myopericytes. It arises most commonly in the dermis or subcutaneous tissue of the extremities in adults. METHODS: We describe a myopericytoma that was unusual in its intravascular location. RESULTS: A 54-year-old man presented with a 10-year history of a painful slowly growing 1.5-cm nodule in the subcutaneous tissue of the thigh. Histologic examination of the excised lesion showed that is was entirely contained within the lumen of a vein. It was composed of a proliferation of myoid-appearing spindle cells, which were arranged in a striking concentric pattern around numerous blood vessels, in a manner that accentuated the vessel walls. This pattern is characteristic of myopericytoma. In some areas, fascicles of spindle cells, embedded in a myxoid stroma, bulged into the lumina of lesional vessels, reminiscent of myofibroma/myofibromatosis. Lesional spindle cells were diffusely positive for smooth muscle actin, focally positive for CD34 and were negative for desmin, cytokeratin, S100 protein, HMB-45 and CD31. CONCLUSION: This case illustrates that myopericytoma can be entirely intravascular in its location.     

Ectopic hamartomatous thymoma: a case report with immunohistochemical study and review of the literature

Ectopic hamartomatous thymoma (EHT) is a rare benign tumor. We present a case of EHT, which was seen as subcutaneous mass on the left supraclavicular area in a 19-year-old man. The tumor consisted of spindle cells, epithelial cells, adipose cells, and a small amount of lymphocytes, as described previously. Immunohistochemically, spindle cells were positive for keratin, a-smooth muscle actin, CD34 and vimentin, but negative for desmin and S-100 protein. Lymphocytes were positive for CD45RO but negative for CD20, CD1a, and CD99. Approximately, 5% of cells were positive for MIB-1 and no cells stained for p53 and bcl-2. Recognition of EHT is important and needs to be differentiated from high-grade sarcomas such as synovial sarcoma or glandular malignant peripheral nerve sheath tumor.     

Desmoplastic fibroblastoma: a case presenting as a protruding nodule in the dermis

Desmoplastic fibroblastoma is a rare, benign, soft tissue tumor. We describe a case of superficial desmoplastic fibroblastoma presenting as a protruding nodule. A 41-year-old woman presented with a painless, firm, elevated nodule with ulceration on her left thigh. Histological examination from total excision showed a well-circumscribed tumor in the dermis, which comprised of spindle, oval and stellate cells arranged in a haphazard fashion, accompanied by abundant collagenous stroma and inconspicuous vasculature. Immunohistochemically, the tumor cells were positive for vimentin, and focally positive for alpha-smooth muscle actin and muscle-specific actin, but negative for CD34, S-100 protein, desmin and beta-catenin. We diagnosed this case as desmoplastic fibroblastoma arising in the dermis and superficial subcutaneous tissue.     

面部多发性毛发平滑肌瘤一例

【摘要】 报告1例面部多发性毛发平滑肌瘤。患者男,43岁,右侧面部及额头部红色斑丘疹,伴冬季疼痛20年余,近4年加重。临床表现为粟粒至黄豆大小,高出皮面的丘疹和结节分布于右侧面颊部以及额部右侧,呈淡红色至红色,簇集状,质地坚实,基底稍呈浸润状。冰块实验阳性。患者无其他系统疾病。皮损组织病理检查：表皮大致正常,真皮内见肿瘤细胞不规则聚集或交织成束,肿瘤细胞细长,胞浆嗜酸,胞核两端钝圆或呈雪茄样,免疫组化显示平滑肌强阳性的特征：Desmin和SMA（+）,结合临床诊断多发性毛发平滑肌瘤。由于该患者皮损面积大,未能手术切除,随访。     

Clear cell myoepithelial carcinoma of the skin. A case report

Myoepitheliomas are tumors of myoepithelial cells, most frequently diagnosed in the salivary glands. Cutaneous location is very rare, especially for malignant variant. We report a case of recurrent cutaneous myoepithelial carcinoma of the femoral region in a 51-year-old woman. Histologically, the tumor was confined to the dermis and superficial subcutaneous fat tissue, exhibiting typical multinodular pattern. The majority of tumor cells were of clear cell type, although rare epithelioid and spindle cells were also present. Nuclear atypia, mitotic activity of 12 mitoses per 10 microscopic high power fields and Ki-67 labeling index of 20%, as well as three recurrences, corroborated the malignant nature of the tumor. Immunohistochemistry showed positivity for cytokeratin, epithelial membrane antigen, vimentin, S-100 protein and myogenic markers (α-smooth muscle actin and muscle-specific actin HHF-35) in keeping with the myoepithelial cell immunophenotype. Staining for CD34, desmin and HMB-45 was negative. Myoepithelial carcinoma should be considered in the differential diagnosis of cutaneous neoplasms composed predominantly of clear cells.     

Localized multiple glomangiomas on the foot

We report a 15-year-old Japanese male with multiple, soft, blue and painless nodules on the left foot. The lesions had developed when the boy was 3 years old, and had enlarged gradually thereafter. None of his family members had any similar eruptions. All the lesions were resected under local anesthesia. Histological examination revealed cystically dilated spaces lined by endothelial cells and a few outer layers of glomus cells in the dermis and fat tissue. Immunohistochemistry demonstrated that the tumor cells were positive for α-smooth muscle actin. We diagnosed this case as localized multiple glomangioma. Multiple glomus tumors are much less common than solitary ones, and localized multiple glomus tumors are extremely rare. Because the clinical differential diagnosis of multiple glomangiomas includes common venous malformation, particularly blue rubber bleb nevus syndrome, histopathological studies should be performed.     

黏液炎性纤维母细胞肉瘤

【摘要】 患者男,73岁。左小腿红斑、斑块伴微痒2年,加重为结节、肿块伴疼痛半年余。皮肤科检查：左小腿伸侧、腓侧中下1/3处多个大小不一红斑、斑块、结节、肿块。肿块质地坚韧,基底深在,可活动,边界不清,压痛明显。肿块表面皮肤部分外观正常。组织病理学检查：表皮未见明显异常;真皮中下部及皮下脂肪层可见梭形细胞及大小不一、胞体大、胞质红染、核大、浓染不规则的细胞,呈片状分布,其中可见病理性核分裂象,间质内可见淡蓝染物质,其间杂有淋巴细胞浸润。间质阿新蓝染色阳性。免疫组化染色：梭形细胞及异形大细胞弥漫性强阳性表达波形蛋白（Vim）,30% ~ 40%瘤细胞表达Ki67,CD34和CD68部分细胞阳性,而白细胞共同抗原、人黑素瘤S100蛋白、pCK、CD31、平滑肌肌动蛋白及结蛋白均为阴性。诊断：黏液炎性纤维母细胞肉瘤。     

Infantile Myofibromatosis: Report of Two Cases

Two cases of solitary type infantile myofibromatosis (IM) were presented. Case 1 was a 6-month-old male infant with a firm, dark red, fixed tumor on his right knee. A computerized tomographic scan revealed that the tumor was attached to the underlying muscle. Case 2 was a 1-month-old male infant with a tumor on his right knee, similar to that in case 1. In neither case was there any clinical evidence of visceral involvement. Histological and immunohistochemical findings were similar. The lesions appeared histologically as non-encapsulated nodules composed of whorled fascicles of spindle-shaped cells and a vascular element with a hemangiopericytoma-like appearance. The tumor cells were positively stained with PTAH. They were positive for α-smooth muscle actin and vimentin, but negative for desmin. These findings support the myofibroblastic nature of IM. In case 2, the tumor regressed spontaneously at the age of 12 months. Unlike the multicentric form, spontaneous regression of the solitary form of IM has not previously been reported.     

皮肤平滑肌瘤1例

报告1例多发性毛发平滑肌瘤。患者女，64岁。躯干出现皮疹3年，临床表现为躯干、四肢散在红褐色丘疹、结节。皮肤组织病理显示，真皮可见较多群集束关和团块状杂乱排列平滑肌束。免疫组化证实过度增生的纤维为平滑肌。     

Genital leiomyomas of the male nipple: two cases

BACKGROUND: Genital leiomyoma is a rare benign solitary skin tumor, not painful, developed from smooth muscle. Genital leiomyoma arising from the nipple is extremely rare, especially in males.CASES REPORT: A 47 year-old male had a 2 cm cutaneous plaque with nodules located on the right nipple. This plaque was circumscribed, erythematous, pruriginous and was not painful. The lesion had been noticed by the patient two years ago. A 37 year-old male showed a 1.5 cm cutaneous plaque located on the left nipple. The plaque was slightly erythematous, pruriginous, not painful and had been noticed by the patient 5 years earlier. Histology provided the diagnosis of genital leiomyoma in both cases. No surgical therapy was performed.DISCUSSION: Cutaneous leiomyomas are classified in 3 types regarding their origin: multiple or solitary piloleiomyoma, arising from arectores pilorum muscles, solitary genital leiomyoma, arising from the dartoic, vulvar, or mammillary muscles, and solitary angioleiomyoma, arising from the vein muscles. Clinically, genital leiomyoma is a 1 cm diameter solitary erythematous, firm nodule. According to many authors, genital leiomyoma is asymptomatic, but in the 2 patients, the lesions were pruriginous. Surgical excision is usually performed.     

A Case of Myopericytoma on the Lower Leg

Myopericytoma (MP) is a benign tumor composed of cells that show apparent differentiation towards putative perivascular myoid cells called myopericytes. It arises most commonly in the dermis or subcutaneous tissue of the extremities in adults. The most common presentation is a well-circumscribed, slow-growing painless firm mass. A 45-year-old woman presented with a 2-year history of a painless, slowly growing 0.9×0.7 cm sized firm mass in the subcutaneous tissue of the posterior side of the right lower leg. We presumed this lesion to be an epidermal cyst, pilomatricoma or calcinosis cutis and performed an excisional biopsy. The histologic examination showed that it was composed of spindle-shaped myoid-appearing cells in a concentric arrangement, intimately associated with thin-walled vascular channels. Lesional spindle cells were diffusely positive for smooth muscle actin and were negative for CD34, desmin and S100 protein. From these findings, we diagnosed this lesion as a myopericytoma.     

A unique case of apocrine carcinoma on the male pubic skin: Histopathologic and ultrastructural observations

We report a case of cutaneous adenocarcinoma on the pubic region of a 56-year-old male. The exophytic tumor showed solid, ductal, and glandular patterns with decapitation secretion and mucinous carcinoma-like nests. Despite the exophytic nature of the lesion, an invasive growth pattern into the deep dermis and subcutaneous fat was seen. An additional characteristic of this tumor was the presence of Paget's phenomenon. From these findings, we conclude that this tumor is an apocrine adenocarcinoma having an unusual clinical appearance and unique histopathological features which have some similarities to apocrine carcinoma of the breast and some to syringocystadenoma papilliferum and nipple adenomatosis.     

Congenital multiple plaque-like glomangiomyoma.

Congenital glomus tumor is a rare clinical variant of glomus tumor, and glomangiomyoma is the least frequent histologic type of glomus tumor. We report a case of congenital multiple plaque-like glomangiomyoma in a 38-year-old man with multiple nodules and plaques on his left arm and forearm. Histopathologic study showed an angiomatous, nonencapsulated tumor with numerous highly folded dilated vascular lumina scattered throughout the dermis. The lumina were lined by a single layer of flat endothelial cells, and one to several rows of glomus cells were observed adjacent to the endothelial cells. Around large vessels, there was a gradual transition from glomus cells to elongated mature smooth muscle cells with thin and long "blunt-ended" nuclei. Immunohistochemically, there were strong positive reactions for cytoplasmic alpha-smooth muscle actin in glomus cells and smooth muscle cells, vimentin in glomus cells and endothelial cells, and desmin in the smooth muscle cells only. To our knowledge, this is the first case report of congenital multiple plaque-like glomus tumor with the microscopic appearance of a glomangiomyoma.     

Multiple leiomyoma as a possible sign of aggressive renal cancer

A 53-year-old Chinese man presented with a history of painful lesions on the chest of 20 years' duration. He experienced sharp pain especially on touching and after spicy food. The lesions were stable with no increase in size or number. He was otherwise well. There was no significant family history. Physical examination revealed multiple, grouped, pink papules on the left chest, extending to the right back in a segmental distribution, each measuring 2-5 mm (Figs 1 and 2). They appeared pearly and keloid-like, and had a firm consistency. A punch biopsy specimen was obtained and sent for histopathologic examination (Figs 3 and 4). This revealed a circumscribed, nonencapsulated tumor with a Grenz zone below the epidermis. It was composed of interlacing fascicles of bland spindle cells with elongated nuclei and blunt ends, typical of a cutaneous leiomyoma. The patient subsequently underwent computed tomography of the abdomen, which did not show any renal or abdominal masses.     

A synovial sarcoma beneath the pectoralis major muscle

Synovial sarcoma is a rare malignant neoplasm that develops most frequently in the extremities. A 68-year-old man presented with a painful mass on the right side of his chest with a 10-year history. Gross findings revealed a mass beneath the pectoralis major muscle. The pathologic findings showed the tumor was predominantly composed of spindle cells the arranged in compact interdigitating fascicles and scattered epithelial nests were seen. A diagnosis of synovial sarcoma was made.