Congenital superficial angiomyxoma

Superficial angiomyxomas are rare, benign, dermal and subcutaneous tumours. We describe a 12-year-old girl who presented with a nodular swelling in the midline of her scalp that had been present since birth. Histological examination revealed an ill-defined myxoid lesion within the dermis, comprising spindle cells, blood vessels and occasional multi-nucleate giant cells. Immunohistochemical staining was negative for S-100, cytokeralin and smooth muscle actin, hut locally positive for CD34, Our patient is unusual in that the angionnxoma was present at birth, which has not previously been described. The importance of screening patients with cutaneous myxomas for cardiac lesions is discussed. myxomas were described in 1948 by Stout as ‘true neoplasms composed of stellate cells set in a loose mucoid stroma through which course very delicate reticulin fibres in various directions' and ‘resemble primitive mescnchyme’.¹ They are found throughout the body, most commonly in skeletal muscle and heart, but also in the subcutaneous tissue, pelvis and bone. The cutaneous myxoma is rare. Those lesions with a predominant vascular component are termed ‘angiomyxomas’. They are usually solitary, potentially locally recurrent but non-metastatic, and occur most commonly in the fourth decade. To date, the youngest patient reported with a cutaneous angiomyxoma was 2 years old.     

Decreased CD44 expression and stromal hyaluronate accumulation in myxoid dermatofibroma

BACKGROUND: Dermatofibroma (DF) is a common benign histiocytic tumor, which has several clinicopathological variants. Myxoid DF is one of these variants, which is characterized by a stromal mucin deposition. CD44 is a polymorphic transmembrane glycoprotein and the principal cell surface receptor of hyaluronate (HA), the major component of the extracellular matrix. In a recent study, we have observed an abnormal accumulation of HA in the superficial dermis of transgenic mice with a keratinocyte-specific CD44 expression defect. We have also shown that HA was accumulated in large amounts in the superficial dermis of lichen sclerosus et atrophicus (LSA) lesions and that the epidermal CD44 expression of LSA skin was significantly decreased or lost. In an another study, we have suggested that a decrease in CD44 expression in follicular epithelial proliferations might be correlated with an abnormal HA accumulation in perifollicular solitary cutaneous myxoma. Recently we have also demonstrated that classical DF lesions displayed a strong CD44 expression in tumor cells and a weak HA positivity in tumor stroma whereas CD44 expression was significantly reduced or absent in dermatofibrosarcoma lesions and the tumor stroma showed strong HA staining. OBJECTIVE AND METHODS: Here we present 3 cases of myxoid DF, in which we explored the nature of the mucinous material in myxoid stroma by colloidal iron and hyaluronic acid binding protein stainings, as well as the expression of CD44 in the tumor cells by immunohistochemistry. RESULTS: We show that HA is accumulated in the stroma of all myxoid DF lesions with a significant decrease in CD44 expression in the tumor cells. CONCLUSION: Our results suggest that a decrease in CD44 expression in the tumor cells may result in stromal myxoid changes characterized by an abnormal HA accumulation in myxoid DF.     

A syndrome of various cutaneous pigmented lesions, myxoid neurofibromata and atrial myxoma: the NAME syndrome

A patient with profuse cutaneous pigmented lesions, subcutaneous myxoid neurofibromata and atrial myxoma is described. This is the second report of this syndrome, whose importance lies in the possibility of avoiding the potentially lethal consequences of a treatable cardiac tumour by recognition of distinctive cutaneous manifestations.     

Hyaluronate accumulation and decreased CD44 expression in perifollicular solitary cutaneous myxoma

BACKGROUND: Myxomas are rare cutaneous tumors which may be solitary or associated with Carney's complex, NAME or LAMB syndromes. The mucinous material which constitutes the stroma of cutaneous myxomas is predominantly composed of hyaluronate (HA), the major component of the extracellular matrix. CD44 is a polymorphic integral membrane glycoprotein which serves as the principal cell surface receptor for HA. OBJECTIVE AND METHODS: Here we present 2 cases of solitary cutaneous myxomas displaying microscopically a perifollicular localization, in which we explored the nature of the accumulated mucinous material by colloidal iron and HA-binding protein stainings, as well as the epidermal expression of CD44 protein by immunohistochemistry. RESULTS: We show that HA is accumulated in the stroma of the cutaneous myxoma lesions and that the protein expression of CD44 in the keratinocytes of the trichofolliculoma-like epithelial buds projecting from the hair follicle centering these lesions is significantly decreased. CONCLUSIONS: Our results suggest that a decrease in CD44 expression in follicular epithelial proliferations may be correlated with an abnormal HA accumulation in cutaneous myxoma.     

Angiomyxoma of the nasal dorsum treated by Mohs surgery

Cutaneous angiomyxomas are myofibroblastic neoplasms with locally aggressive behaviour and a high risk of recurrence. We describe a case of a solitary cutaneous angiomyxoma presenting on the nasal dorsum of a 28‐year‐old man, excised with Mohs surgery using permanent section control and repaired with an advancement flap. Histology showed myxoid nests of bland CD34‐positive and vimentin‐positive stellate and spindled cells in the deep dermis and abundant thin‐walled blood vessels. An echocardiogram, performed to rule out the possibility of a cardiac myxoma with cutaneous embolisation, was normal.     

Carney complex: report of a Japanese case associated with cutaneous superficial angiomyxomas,labial lentigines,and a pituitary adenoma

We report the case of a 12-year-old female patient who manifested multiple cutaneous angiomyxomas and labial pigmented lesions. Although the familial history was not confirmed in the present case, autosomal dominant inheritance has been reported to be involved in the pathogenesis of this condition. In addition to the cutaneous complications, magnetic resonance (MR) images revealed the presence of a pituitary adenoma, which provoked an elevation of serum growth hormone (GH) level. On the other hand, no significant symptoms such as cardiac myxoma, myxoid fibroadenoma of the breast, or adrenocortical complaints suggesting Cushing syndrome, were detected. In the Japanese literature, only a few cases of this disorder have been described in the form of brief reports. There have been only a few similar cases described in the dermatological field, except for one report diagnosed as Carney complex in 1990. Therefore, the present case seems to be the first Japanese case of typical Carney complex manifesting major clinical complications, including angiomyxomas, lentigines, and a pituitary adenoma, which induced endocrine overactivity.     

Bizarre Cutaneous Neurofibromas

Bizarre cutaneous neurofibroma is an uncommon benign neoplasm. Microscopically, it is usually characterized by stellate and polyhedral cells embedded in a myxoid stroma, and less commonly by solid sheets of epithelioid cells. Cellular pleomorphism and mitotic figures are regular features and have resulted in erroneous diagnosis of malignancy. The mucinous material has the staining characteristics of a sulfated mucosubstance, probably chondroitin sulfate B. Terms previously applied to this lesion include nerve sheath myxoma. Pacinian neurofibroma, myxoid neurofibroma, and neurotheceoma.     

Primary cutaneous myxoid spindle cell squamous cell carcinoma: a clinicopathologic study and review of the literature

Mucocutaneous squamous cell carcinoma (SCC) may rarely exhibit intracellular mucin production. Extracellular mucin production is an even rarer finding in SCC that is not well documented in the literature. Here, we report six cases of primary cutaneous and mucocutaneous SCC with prominent extracellular stromal mucin deposition and an epithelial spindle cell component. We propose the term ‘yxoid spindle cell SCC’ (MSC SCC) to describe the histologic characteristics of these six cases. We also propose a set of histologic and immunohistochemical findings for distinguishing MSC SCC from primary cutaneous and metastatic spindle cell neoplasms including other sarcomatoid carcinomas, myxoid sarcomas and the spindle cell variant of atypical fibroxanthoma (AFX). The criteria can also help discern MSC SCC from spindle cell melanomas, which may rarely show a prominent myxoid stroma. Given the small numbers of cases reported to date, the presence of prominent myxoid stroma in primary cutaneous spindle cell SCC has unknown prognostic significance at this time. Yang A, Hanley A, Velazquez EF, Cassarino DS. Primary cutaneous myxoid spindle cell squamous cell carcinoma: a clinicopathologic study and review of the literature.     

Cutaneous neoplasms with prominent Verocay body-like structures: the so-called "rippled pattern"

A striking appearance resulting from alternating areas of epithelial cell cords and stroma seen in some cutaneous adnexal neoplasms has been referred to as the "rippled pattern." Histologically, this pattern may be indistinguishable from Verocay bodies described in schwannomas. A number of common and clinically diverse cutaneous neoplasms can be linked by the presence of this unusual growth pattern. The heterogeneous group of tumors that have been known to demonstrate this feature includes those with epithelial, adnexal, fibrohistiocytic, mesenchymal, and melanocytic lineage. The objective of this review is to alert the dermatopathologist to the range of neoplasms, which can potentially show this attribute, so that a misdiagnosis can be avoided.     

Eccrine syringofibroadenoma (Mascaró). An acrosyringeal hamartoma

Two patients with eccrine syringofibroadenomas were studied. The first patient had a 3-year history of asymptomatic, unilateral, linear, moist mosaic plaques of the lower part of the left leg and foot; the second patient had a solitary papule on the back. Histologically, both tumors exhibited superficial elongated strands of eccrine ductal epithelium containing occasional lumina lined by an eosinophilic cuticle. The stroma was loose, myxoid, and fibrovascular. The secretory portions of the eccrine glands were ectatic in the first patient but were not seen in the second patient. We believe these lesions represent acrosyringeal hamartomas (nevi), although some authors interpret them as adenomas. The literature seems to indicate that lesions with similar histologic features may be solitary, multiple, or combined with other neoplasms; in other cases, the lesions may possibly represent an unusual morphologic expression of hidrotic ectodermal dysplasia.     

Epidermal basaloid proliferation in cutaneous myxomas

BACKGROUND: Basaloid epidermal proliferations, which histologically resemble basal cell carcinoma, have been described overlying dermatofibromas. Several etiologies have been proposed. Cutaneous myxomas are also benign mesynchymal tumors. PURPOSE: Basaloid proliferations have been noted overlying cutaneous myxomas. We have undertaken a study to attempt to differentiate whether these are basal cell carcinomas or benign basaloid proliferations. METHODS: Thirty cases of cutaneous myxomas were included in this study. The lesions were stained with hematoxylin-eosin and alcian blue. Immunohistochemical staining for both epidermal growth factor receptor (EGF-r) and p53 protein was performed on the cutaneous myxomas with epidermal basaloid proliferation. RESULTS: Of the 30 cases of cutaneous myxomas, nine were found to have an associated overlying basaloid proliferation. The basaloid proliferations were limited to the epidermis overlying the myxoid changes within the dermis. Mitotic figures were rare. Staining for p53 protein showed scattered positive staining in the basal cells in both the basaloid proliferations and adjacent epidermis. EGF-r showed positive staining of the overlying epidermis and basaloid proliferation in five cases. CONCLUSIONS: We report basaloid proliferations overlying cutaneous myxomas and propose that these represent benign adnexal proliferations rather than superficial basal cell carcinoma and are analogous to the basaloid proliferations overlying dermatofibromas.     

Low-grade adnexal carcinoma of the skin with multidirectional (glandular, trichoblastomatous, spiradenocylindromatous) differentiation

The conjoint occurrence of follicular, sebaceous, or apocrine differentiations in a cutaneous adnexal neoplasm is a known event, more often encountered in benign neoplasms, whereas reports of cutaneous malignant adnexal tumors with bilineage or trilineage differentiation are few. A new case of a cutaneous malignant adnexal neoplasm with multidirectional differentiation is reported here. A 57-year-old woman presented with a long-standing, slowly growing, asymptomatic solitary tumor the size of a large nut in the coccygeal area, which was surgically excised. Ten years after the surgery, there was no evidence of recurrence or metastasis. Microscopically, the neoplasm was located in the dermis with focal extension into the subcutis. It was asymmetric, horizontally oriented, and mostly composed of small nodules that varied in shape from round and oval aggregations to elongated strands and irregular islands; the nodules were either clustered, formed a jigsaw puzzle-like pattern or were dispersed. The nodules were composed of small basaloid cells sometimes intermixed with larger cells with ample cytoplasm forming glandular structures. Rare nodules resembled elements seen in a spiradenoma by containing scattered lymphocytes and globules of hyalinized eosinophilic basal membrane material. The stroma was paucicellular, but focally it resembled that seen in perifollicular mesenchyme. Mitotic figures, including abnormal ones, were infrequent, but mild nuclear pleomorphism, nuclear crowding, and individual cell necrosis were easily appreciable in both small basaloid cells and cells with clear cytoplasm. Perineural invasion was apparent. We classified this tumor as a well-differentiated adnexal carcinoma demonstrating combined follicular and apocrine differentiation. It differs from previously published cases of malignant adnexal tumors with multidirectional differentiation and further exemplifies the spectrum of diversity encountered in malignant proliferations with differentiation toward the folliculosebaceous-apocrine unit.     

Brooke-Spiegler syndrome: report of a case with combined lesions containing cylindromatous, spiradenomatous, trichoblastomatous, and sebaceous differentiation

Brooke-Spiegler syndrome is an autosomal dominantly inherited disease with predisposition to cutaneous adnexal neoplasms, most commonly cylindromas and trichoepitheliomas. We report a patient in whom 11 lesions were removed from the scalp and face for various reasons over a period of 3 years. The histopathological survey revealed a plethora of benign adnexal neoplasms showing apocrine, follicular, and sebaceous differentiation occurring independently and conjointly. The histopathological spectrum in our patient included cylindromas, spiradenomas, trichoepitheliomas, small nodular trichoblastomas, and lymphadenomas. Many lesions had hybrid features of two or more neoplasms. By far the most common composite tumor was spiradenocylindroma. Some spiradenocylindromas demonstrated prominent sebaceous or trichoblastomatous differentiation or both. We suggest the terms "sebaceous spiradenocylindroma" and "trichospiradenocylindroma" for these lesions. The occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas is a further proof that spiradenoma and cylindroma are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit.     

Myxofibrosarcoma presenting in the skin: clinicopathological features and differential diagnosis with cutaneous myxoid neoplasms

Myxofibrosarcoma (myxoid malignant fibrous histiocytoma) is one of the most common fibroblastic sarcomas in the older patient, where it can sometimes present with anatomically deceptive boundaries. Myxofibrosarcoma is now fully characterized as a distinctive and definable pathologic entity. Clinically there is a tendency for predominantly subcutaneous, multinodular, diffusely infiltrative growth, which may extend to the overlying dermis and present as a cutaneous lesion. Histologically myxofibrosarcoma comprises a spectrum ranging from hypocellular low-grade myxoid to high-grade pleomorphic sarcoma. We report herein 6 cases of myxofibrosarcoma each with dermatological presentation as a cutaneous nodule. The dermal component in each of the lesions was low- to intermediate-grade and predominantly myxoid resulting in confusion with benign myxoid neoplasms in small biopsy specimens. The purpose of this series is to focus the attention of workers in dermatology on a subject rarely discussed in dermatopathology literature: the cutaneous presentation of myxofibrosarcoma and the potential for clinical and histologic misinterpretation, as benign dermal lesions.     

Basal cell carcinomas showing histological features generally associated with cutaneous adnexal neoplasms

Basal cell carcinoma (BCC) is the commonest malignant neoplasm in humans. Although a histopathological diagnosis of BCC is straightforward in the vast majority of cases, unusual histological variants can present a diagnostic challenge. A small proportion of BCCs show features which are generally associated with cutaneous adnexal neoplasms. Such changes may involve either the epithelium or the stroma and can mislead the pathologist particularly in small biopsies. Despite the growing evidence which speculate that BCC is a primitive follicular tumor, it is unusual to encounter tumors which actually show definitive signs of adnexal differentiation. This review aims to address this somewhat overlooked aspect of a very common tumor and offers practical guidance to distinguish them from adnexal neoplasms which they might mimic.     

Immunohistochemical study of calretinin in normal skin and cutaneous adnexal proliferations

Calretinin is a calcium-binding protein member of the EF-hand family. The presence of calretinin has been demonstrated in certain stages of the cellular cycle in a wide variety of normal and neoplastic tissues. The main aims of our study were (1) to investigate what structures of the normal skin and cutaneous adnexal proliferations express immunoreactivity for calretinin and (2) to determine the value of immunohistochemical expression for calretinin as a marker for follicular, sebaceous, apocrine, and eccrine differentiation in cutaneous adnexal proliferations. We studied 139 biopsy specimens, including 10 cases of normal skin of different locations and 129 benign and malignant cutaneous adnexal proliferations. In normal skin, we found that calretinin is expressed in the innermost cell layer of the outer root sheath in anagen hair follicle, in both the duct and sebolemma of the sebaceous gland, in the secretory portion of eccrine glands, and in mast cells of the stroma. In cutaneous adnexal proliferations, we found strong immunoreactivity for calretinin in tricholemmal cysts, tricholemmomas/inverted follicular keratoses, tumors of follicular infundibulum, and in some basal cell carcinomas. Focal positivity was also seen in trichoadenomas, trichoblastomas/trichoepitheliomas, pilomatricomas, proliferating tricholemmal tumors, pilar sheath acanthomas, trichofolliculomas, follicular hybrid cysts, cutaneous mixed tumors, steatocystomas, sebaceous hyperplasias, and sebaceomas. These results demonstrate that immunohistochemical study for calretinin may be helpful to identify the innermost cell layer of the outer root sheath in anagen hair follicle and the cutaneous adnexal proliferations showing differentiation toward this structure. Calretinin immunoreactivity supports eccrine differentiation in some sweat gland neoplasms, and it is also useful in identifying neoplasms with ductal sebaceous differentiation.     

Use of CD34 in assessing the relationship between stroma and tumor in desmoplastic keratinocytic neoplasms

It has been hypothesized that the ability for neoplastic growth of epithelial-derived neoplasms depends upon the stroma. There are currently some studies which show that the stroma surrounding basal cell carcinomas (BCC) is derived from the tumor. In contrast, other studies provide evidence that the stroma is a host-derived response to the tumor. In order to further examine the nature of stroma enveloping cutaneous epithelial neoplasms, we examined a series of tumors which contain abundant stroma, including morpheic type BCC (MBCC), desmoplastic trichoepitheliomas (DTE), and microcystic adnexal carcinomas (MAC). The spindle-shaped cells surrounding the epithelial islands of the two malignant tumors, MBCCs and MACs, were negative in 70% and 100% of cases, respectively, for CD34. In contrast, the spindle-shaped cells surrounding the islands of the benign DTEs were positive for CD34 in 80% of cases. The results suggest that whereas stromal cells surrounding DTEs resemble the CD34-positive perifollicular cells, the spindle-shaped stromal cells surrounding MBCC and MAC are CD34 negative, and may be derived from sources other than the normal mesenchymal tissue surrounding cutaneous appendages.     

Basal cell carcinoma with matrical differentiation.

Three cases of basal cell carcinoma showing shadow cells within basaloid islands have been described using the term basal cell carcinoma with matrical differentiation for this histologic variant. We present four new cases of basal cell carcinoma with evidence of matrical differentiation. Unlike the cases previously published, these lesions showed nests of shadow cells either within the lobules of basaloid cells or forming nests in the stroma. We also noted the presence of a foreign body reaction and calcification. These neoplasms illustrate the capability of basal cell carcinoma to differentiate toward hair matrix cells. Basal cell carcinoma with matrical differentiation must be added to the uncommon variants of basal cell carcinoma showing adnexal differentiation. A parallel between the degrees of differentiation of the cutaneous sebaceous neoplasms with those showing matrical differentiation is proposed.     

Cutaneous embolization of cardiac myxoma

Atrial myxoma is the most common primary tumour of the heart. Skin manifestations in patients with a cardiac myxoma are frequent and may be due to cutaneous emboli, or may be specific findings as part of more complex syndromes. We present a 33-year-old-man with a history of episodes of pain in both legs and an ischaemic neurological event, who also had episodes of acral papular erythematous lesions on the legs and feet including the soles. The histological finding of dermal vessels occluded by a myxomatous material was the clue to the diagnosis of a cardiac myxoma. The diagnosis of this entity can be very difficult, because of the broad spectrum of clinical features; rarely the skin manifestations lead to the diagnosis of this tumour. The histological recognition of the myxomatous emboli is of vital importance for the diagnosis and treatment of this disease.