Juvenile Hyaline Fibromatosis: An Expanded Clinicopathologic Spectrum

A female infant had the typical cutaneous and soft tissue lesions of juvenile hyaline fibromatosis with the characteristic histologic and ultrastructural features of the disease. Her clinical course and autopsy findings strongly resembled those of infantile systemic hyalinosis, suggesting that the two conditions may be parts of a spectrum.     

CD34‐positive infantile myofibromatosis: Case report and review of hemangiopericytoma‐like pattern tumors

We describe a case of CD34‐positive infantile myofibromatosis with hemangiopericytoma‐like pattern. A 2‐day‐old Japanese boy presented with multiple hemispherical nodules on the extremities and back. There was a biphasic histological growth in the dermis, accompanied by a hemangiopericytoma‐like pattern with antler‐like branching vessels. Tumor cells were oval to spindle‐shaped myoid cells with bland appearance. Immunohistochemically, vimentin, calponin and CD34 were positive, while α‐smooth muscle actin, h‐caldesmon, HHF35 and desmin were negative. Although CD34 was positive, the present case could be diagnosed as infantile myofibromatosis. Myopericytoma, myofibroma/myofibromatosis, glomus tumor, glomangiopericytoma and angioleiomyoma share a continuous spectrum of benign hemangiopericytoma‐like pattern tumors. Myofibroma/myofibromatosis is nearly included in myopericytoma among pericytic (perivascular) tumors, and could be positive for CD34. Several immunohistochemical panels of smooth muscle markers are needed for the diagnosis of pericytic (perivascular) tumors.     

Extra-acral calcifying aponeurotic fibroma: a distinctive case with 23-year follow-up

Calcifying aponeurotic fibroma (CAP) is an unusual but well-characterized soft tissue neoplasm that typically involves the digits of children and frequently recurs locally. This report describes a case from the subcutis of the lumbosacral region. A 26-year-old man initially presented at age 3 and developed three recurrences over a 23-year period each at approximately 8-year intervals (ages 10, 18, and 26). The microscopic findings in all recurrences showed a lobulated, poorly circumscribed proliferation of dense fibrous tissue containing epithelioid-like fibro-blasts, multinucleated cells, and islands of metaplastic chon-droid differentiation with focal calcification. Despite origin from an unusual anatomic site, this case reported herein demonstrates the classical morphologic features and clinical history of CAT which showed little in the way of morphologic evolution despite 23 years of persistence. The clinical and histologic features helpful in distinguishing CAP from infantile fibromatosis and soft tissue chondroma are discussed.     

Congenital myofibroma of the skin mimicking a piloleiomyoma

Myofibroma is an uncommon benign soft tissue disorder, which is usually congenital or present in early infancy. Myofibroma usually manifests as a single mass. When there are multiple lesions, the term myofibromatosis is used. The characteristic histopathological feature of the myofibroma is the coexistence of two distinct areas. One area mainly contains plump spindle cells with thin blunt‐ended nuclei and eosinophilic cytoplasm, thus indicating myoid characteristics. The other area contains either round or polygonal cells with slightly pleomorphic, hyperchromatic nuclei or small spindle cells typically arranged around a distinct hemangiopericytoma‐like vascular pattern. In the present case, the majority of the tumor was composed of the plump myoid spindle cells. This led to an initial diagnosis of a piloleiomyoma. However, the tumor cells were not immunohistochemically positive for desmin. Moreover, careful examination revealed a hemangiopericytoma‐like vascular pattern characterized by the presence of high cellular areas with irregular vascular spaces. These features led to the final diagnosis of the myofibroma. It is therefore important to recognize the leiomyoma‐like variants of myofibromas. Inoue T, Sada A, Mori T, Misago N, Narisawa Y. Congenital myofibroma of the skin mimicking a piloleiomyoma.     

Congenital Myofibroma Masquerading as an Ulcerated Infantile Hemangioma in a Neonate

Abstract: We report a case of a solitary infantile myofibroma masquerading as an ulcerated infantile hemangioma. Infantile myofibroma is a rare soft tissue tumor that has a good prognosis in the solitary form. It may be difficult to distinguish clinically from more common tumors of infancy such as an infantile hemangioma or from other rare entities and therefore requires a biopsy for definitive diagnosis.     

良性血管周皮细胞瘤

报告1例良性血管周皮细胞瘤。患者女,39岁。左上肢出现暗红色增生性斑块伴疼痛半年。皮损为椭圆形暗红色斑块,表面无破溃,质地较硬,有明显触痛,周围有卫星状分布的针帽大暗红色丘疹。组织病理学检查：血管周皮细胞增生,细胞无异形性。网状纤维染色显示肿瘤细胞局限于网状纤维环的外围。诊断：良性血管周皮细胞瘤。     

Reticular infantile hemangioma of the limb can be associated with ventral-caudal anomalies, refractory ulceration, and cardiac overload

Abstract:  We describe six patients with an uncommon variant of infantile hemangioma that we have termed reticular , occurring in the extremity, which were associated with intractable ulceration, anogenito-urinary-sacral anomalies, and sometimes cardiac overload. The extreme end of the spectrum is exemplified by a male neonate who presented with a stained, enlarged, pulsatile lower extremity, and cardiac failure. He also had hepatic hemangiomas and ambiguous genitalia. Progressive soft tissue necrosis and bony destruction necessitated amputation. The histopathologic features differed from those of typical infantile hemangioma: infiltrative (not lobular) and involving fascia, muscle, and bone.
The mid-spectrum is illustrated by five females with reticular infantile hemangioma of the lower limb, buttock, and perineum. Four of these infants had a ventral-caudal anomaly, including omphalocele, recto-vaginal fistula, solitary/duplex kidney, imperforate anus, and tethered cord; one infant also had hepatic hemangiomas. Deep ulcerations healed following corticosteroid therapy; one patient required skin graft for closure of a thigh wound. The minor end of the spectrum is exemplified a patchy lesion in the distal limb.
The reticular variant of infantile hemangioma can be confused with other vascular anomalies in the limb, such as capillary malformation, cutis marmorata telangiectasia congenita, diffuse arteriovenous malformation (Parkes Weber syndrome) and capillary-lymphatico-venous malformation (Klippel–Trenaunay syndrome). The macular network-like appearance of the tumor and coexisting ventral-caudal structural anomalies is analogous to the association of posterior fossa brain malformations, hemangiomas, arterial anomalies, coarctation of the aorta and cardiac defects, and eye abnormalities association in the craniofacial region.     

A Case of Kaposiform Hemangioendothelioma and Kasabach‐Merritt Phenomenon

Kaposiform hemangioendothelioma (KH) is a vascular tumor of intermediate malignancy that occurs in childhood, of which 50% are present at birth. The tumor has a predilection for the trunk, extremities, and retroperitoneum. It is commonly associated with Kasabach‐Merritt phenomenon, a consumptive coagulopathy characterized by profound thrombocytopenia and hypofibrinogenemia. The histologic differential diagnosis of kaposiform hemangioendothelioma includes infantile hemangioma, tufted angioma, Kaposi's sarcoma, and spindle cell hemangioendothelioma. We present a case of a neonate with a soft tissue mass encompassing the proximal two‐thirds of the right thigh. After delivery by Ceasarean section for failure to progress, the patient developed repiratory failure, consumptive coagulopathy and intracranial hemorrhage. The initial clinical differential diagnosis included KH, infantile hemangioma, and infantile fibrosarcoma, all entities which have been associated with Kasabach‐Merritt phenomenon. An biopsy demonstrated a nodular vascular proliferation composed of grouped, spindled endothelial cells forming irregular, slit‐like vascular lumens. There were associated fragmented red blood cells and hemosiderin deposits. The tumor cells were focally positive for D2–40, an antigen specific for lymphatic endothelium and expressed by KH, and were negative for GLUT‐1, an antigen expressed in infantile hemangiomas but not KH. The histologic and immunohistochemical findings confirmed the diagnosis of KH.     

Congenital infantile fibrosarcoma: a clinical mimicker of hemangioma

Congenital infantile fibrosarcoma (CIFS) is a rare pediatric soft tissue tumor; clinically, it presents as a highly vascular mass and may simulate a hemangioma. It usually occurs in the first year of life and has a relatively better prognosis compared to other aggressive spindle cell sarcomas of childhood. We report a patient with CIFS who presented with a nonspecific ulcerated mass lesion over the right shoulder region that was clinically diagnosed as a benign vascular lesion. Histology revealed a highly cellular tumor with closely packed fascicles of spindle cells. Immunohistochemically, the tumor cells expressed vimentin.     

Ossifying fibromyxoid tumor of soft parts: a case report and review

Ossifying fibromyxoid tumor of soft parts is a recently described, rare but morphologically distinctive tumor of soft tissue, including subcutaneous soft tissue. We report a case of ossifying fibromyxoid tumor of soft parts which occurred in the subcutaneous tissue of a 68-year-olcl male, and review the clinical, histologic, and immunohistologic features of this tumor. Ossifying fibromyxoid tumor of soft parts tends to occur in the subcutaneous tissue and have been reported from the head and neck, upper and lower extremities, and trunk. Immunohistologic studies have supported a neural origin. While considered benign, local recurrence after excision is common and these tumors should be excised with clear margins to prevent recurrence.     

Foreign-body reaction with Mycobacterium abseccus superinfection

Mycobacterium abscessus is a rare cause of skin and soft tissue infections that often results from inoculation with contaminated foreign material. A 41-year-old woman is described regarding an outbreak of M. abscessus following soft tissue augmentation. Clinical features and treatment options are reviewed.     

Palisaded and verocay body prominent leiomyoma of deep soft tissue

Leiomyoma of deep soft tissue is a very rare tumor, which is sometimes confused with leiomyosarcoma, histopathologically. We describe a case of palisaded and Verocay-body prominent leiomyoma of deep soft tissue. The lesion was characterized by areas of nuclear palisading with Verocay-body like formation in addition to the features of leiomyoma.     

Primary giant cell tumor of soft tissue

BACKGROUND: Primary giant cell tumor of soft tissue, also known as soft tissue giant cell tumor of low malignant potential, is a rare soft tissue tumor located in both superficial and deep soft tissue. Histologically, these lesions bear a close resemblance to their bony counterparts, giant cell tumor of bone, with round to spindle-shaped cells intimately admixed with uniformly scattered osteoclast-like multinucleated giant cells. In 1989 in the dermatology literature, two malignant giant cell tumors of soft parts were described that filled the dermis and extended into the subcutaneous tissue. METHODS: The authors report the rare occurrence of a giant cell tumor of soft tissue occurring primarily in the dermis that lacks overtly malignant features and clinically was thought to be an epidermal inclusion cyst. RESULTS: Light microscopy revealed a non-encapsulated cellular dermal tumor containing numerous osteoclast-like giant cells. Cytologic atypia was minimal and the mitotic count averaged 2-3/10 HPF. The histologic differential diagnosis is also discussed. CONCLUSION: Giant cell tumor of soft tissue is a rare neoplasm of the skin, however, recognition of this tumor is important due to its behavior as a low-grade malignancy.     

Infantile myofibromatosis: a case report and review of the literature

Infantile myofibromatosis is a rare mesenchymal disorder of infancy and childhood characterized by the formation of tumors in the soft tissues, muscle, bone, and viscera. Disease limited to the soft tissues, muscle, and bone has a good prognosis, and excision is curative; however, visceral involvement may be fatal. We present a case of infantile myofibromatosis in a 1-year-old boy and review the literature.     

Pedunculated hemangiopericytoma-like tumor: peculiar fibroepithelial polyp or fibrous histiocytoma variant

Abstract:  Pathologists are continually challenged with the difficult task of discriminating between innocuous disease processes and potentially malignant entities. Apropos of this concern, we present a series of three cutaneous polypoid lesions that simulated fibroepithelial polyp, yet upon close scrutiny yielded histologic features of solitary fibrous tumor (SFT) or hemangiopericytoma. These pedunculated lesions showed a storiform pattern of spindled cells with interspersed gaping vascular channels reminiscent of SFT or hemangiopericytoma. Interestingly, the immunohistochemical staining profile of these lesions was negative for CD34 and positive for bcl-2 and factor XIIIa. These findings were discordant with SFT and suggest a relationship with fibrous histiocytoma. We propose that this entity represents a hitherto described variant of fibrous histiocytoma known as pedunculated hemangiopericytoma-like fibrous histiocytoma.     

Myoepithelial carcinoma on the right shoulder: Case report with published work review

Myoepithelial carcinoma is a malignant tumor that can differentiate towards myoepithelial cells and commonly occur in the salivary glands. There have been only a few reports of primary cutaneous myoepithelial carcinoma; however, most cases showed subcutaneous involvement and could also be diagnosed as soft tissue myoepithelial carcinoma arising from the subcutis with dermal involvement. It may thus be impossible to distinguish a primary cutaneous from a soft tissue myoepithelial carcinoma. Herein, we describe a case of myoepithelial carcinoma on the shoulder in an 85‐year‐old Japanese woman. The tumor was located in the whole dermis and subcutis; therefore, it could be diagnosed as either a cutaneous or soft tissue myoepithelial carcinoma. We reviewed previous cases of primary cutaneous and soft tissue myoepithelial carcinomas and compared their clinical and immunohistological features. We found no obvious differences in anatomical distribution or immunohistochemical findings. However, the recurrence rate of cutaneous myoepithelial carcinomas seems to be lower than that of soft tissue carcinomas. Such a difference may be attributable to the adequate surgical margin in cutaneous carcinomas compared with the deep‐seated soft tissue carcinomas. The metastatic frequency did not significantly differ between the two types. Although we could summarize from only a small number of cases, these results indicate the difficulty in distinguishing between cutaneous and soft tissue myoepithelial carcinomas; furthermore, it may not be suitable to distinguish them on the basis of aggressive behavior.     

Localized soft tissue angiomatosis with subsequent development of angiolymphoid hyperplasia with eosinophilia

We report an unusual case of arteriovenous (AV) malformation (localized form of soft tissue angiomatosis): a reaction of angiolymphoid hyperplasia with eosinophilia (ALHE) developed over the lesion of this pre-existing AV malformation. To the best of our knowledge, there is no other report of ALHE in association with a pre-existing bona fide AV malformation. A 71-year-old woman consulted our clinic because a reddish, dome-shaped tumor on her preauricular region, present as a slightly elevated, skin-colored tumor since her childhood, had rapidly enlarged and become more elevated with color change during the preceding two months. The histological features of most of the lesion corresponded to those of soft tissue angiomatosis (localized form). The proliferative vessels underlying the soft tissue angiomatosis streamed out and welled into the dermis with an accompanying prominent inflammatory infiltrate composed of lymphoid cells and eosinophils: these histological features were characteristic of ALHE. The recent abrupt clinical changes in the tumor were considered to represent a reaction to the angiomatosis with development of ALHE.     

木村病

Kimura病是一种罕见的、病因不名的、以淋巴结、软组织和唾液腺损害为主的慢性炎性疾病。临床以头颈部肿块伴淋巴系统增生、外周血嗜酸性粒细胞增多和血IgE水平升高为主要表现。此病易与其他疾病如ALHE混淆。组织病理学对诊断有重要意义。此病预后良好,但易复发。     

马拉色菌相关婴儿皮肤病

马拉色菌是人皮肤表面的常驻真菌，能引起婴儿花斑癣，并与婴儿脂溢性皮炎、婴儿特应性皮炎、新生儿头部脓疱病、婴儿及新生儿痤疮的发病相关。这种相关性主要表现在皮损处能检出马拉色菌，且抗真菌治疗有效，在婴儿特应性皮炎的发病中，主要作为抗原。由于婴儿和新生儿的皮肤屏障功能、机体免疫功能等尚不成熟，在患该类疾病时临床表现不典型，较成人有差异，治疗以外用药物为主。     

Cutaneous and subcutaneous fibrohistiocytic tumors of intermediate malignancy: an update

The fibrohistiocytic tumors of intermediate malignancy are uncommon mesenchymal tumors, which typically occur in the skin and subcutis and which may pose significant problems for the dermatopathologist. This article reviews the clinical, histopathologic, and genetic features of dermatofibrosarcoma protuberans, giant cell fibroblastoma, angiomatoid (malignant) fibrous histiocytoma, plexiform fibrous histiocytoma, and soft tissue giant cell tumor (of low malignant potential). The differential diagnosis of these tumors with a variety of benign and fully malignant cutaneous soft tissue neoplasms is discussed.