Epidermodysplasia verruciformis: an unusual malignant transformation.

Epidermodysplasia verruciformis (EV) is a rare, life-long heritable disease caused due to a unique susceptibility to human papilloma virus. The disseminated verrucous lesions and pityriasis versicolor-like lesions persist from early childhood and can transform into a cutaneous malignancy in a fourth of patients. Malignant transformation into syringoid eccrine carcinoma (SEC) has been reported only once so far. SEC is an extremely invasive, rare, locally destructive, slowly growing adnexal tumor. We hereby report the association of EV with SEC in a 29-year-old male.

Primary cutaneous neuroendocrine carcinoma within a cystic trichoblastoma: a nonfortuitous association?

Merkel cell (primary cutaneous neuroendocrine) carcinoma is a rare neoplasm of the skin. Its occurrence has been reported in association with other cutaneous neoplasms (Bowen disease, squamous cell carcinoma) in cases regarded as collision tumors. It has recently been described in association with cysts of the follicle apparatus. We present a unique case of rapidly growing nodular tumor on the left forearm of an 84-year-old woman, which proved to be a Merkel cell carcinoma located within a cystic trichoblastoma. The malignant component located in the center of the lesion had typical histopathological and immunohistochemical features of Merkel cell carcinoma. It was surrounded by an epithelial proliferation, made of K17-positive basaloid cells, whose aspects where those of trichoblastoma in a retiform pattern. Both lesions were intertwined, suggesting that the Merkel cell carcinoma had developed within a previously existing trichoblastoma and that it derived from the follicular Merkel cells present in the trichoblastoma. The unique features of this case, together with the reported cases of Merkel cell carcinoma arising within follicular lesions, and the fact that numerous Merkel cells are normally localized in the adult hair follicle, further support the hypothesis of a histogenetic link between normal follicular Merkel cells and Merkel cell carcinoma.

Trichilemmal carcinoma associated with xeroderma pigmentosa: report of a rare case.

Trichilemmal carcinoma is a rare malignant skin adnexal tumor derived from the outer root sheath epithelium of the hair follicle. We describe a rare case of trichilemmal carcinoma of the upper lip associated with xeroderma pigmentosa in a young patient. We demonstrate that this tumor, as well as the more frequently reported squamous cell carcinoma and basal cell carcinoma can occur in association with xeroderma pigmentosa. Making this diagnosis is imperative as the biological behavior of Trichilemmal carcinoma is less aggressive than that of other epithelial malignancies, requiring a different approach to treatment planning.

Differential expression of mucin core proteins and keratins in apocrine carcinoma, extramammary Paget's disease and apocrine nevus.

BACKGROUND: Apocrine carcinomas are rare, the immunohistochemical characterizations that are incomplete. The purpose of this study was to determine the immunohistochemical characteristics of mucin core proteins and keratins in apocrine carcinoma, extramammary Paget's disease (EMPD) and apocrine nevus. METHODS: We report four cases of apocrine carcinomas along with immunohistochemical analyses: (i) an axillary apocrine carcinoma with an apocrine nevus, (ii) an inguinal apocrine carcinoma, (iii) a vulvar apocrine carcinoma with EMPD and (iv) an axillary apocrine carcinoma with EMPD and an apocrine nevus. RESULTS: The tumor cells of apocrine carcinomas, EMPD and apocrine nevi displayed a positive reaction to MUC-1 and CK7 and a negative reaction to CK20. Apocrine carcinomas had high molecular weight (HMW) cytokeratin(+)/CK5(+)/CK14(-)/MUC5AC(-), EMPD with underlying apocrine carcinoma had HMW cytokeratin(-)/CK5(-)/CK14(-)/MUCA5AC(-) and the apocrine nevi had HMW cytokeratin(+)/CK5(+)/CK14(+)/MUCA5AC(+). CONCLUSION: The immunohistochemical findings suggest that apocrine carcinomas, apocrine nevi and EMPD with underlying apocrine carcinomas are quite different, even though they are all derived from apocrine glands.

Apocrine hidradenocarcinoma showing Paget's disease and mucinous metaplasia.

A 54-year-old man presented with a solitary, erythematous, rapidly growing 1-cm nodule on his scalp that had arisen over the previous 3 months. He had no history of skin cancer. An excisional biopsy of the lesion showed a fairly well-circumscribed but focally invasive tumor consisting of areas of typical-appearing clear cell hidradenoma as well as areas with mucinous goblet-type cells and cells with eosinophilic cytoplasm and decapitation-type secretion. There was marked cellular atypia, numerous atypical mitotic figures and focal necrosis. The tumor cells focally involved the overlying epidermis (Paget's disease). Large areas of mucin were identified throughout the lesion. The tumor cells stained with markers for cytokeratin 7 and focally for EMA and CEA, confirming ductal differentiation. The goblet cells and mucinous areas stained with mucicarmine and PASD. The patient was diagnosed with hidradenocarcinoma with mucinous differentiation. Associated Paget's disease has only rarely been reported, and mucinous metaplasia is a previously unreported feature in hidradenocarcinoma.

Brooke-Spiegler syndrome complicated by unilateral hearing loss.

Brooke-Spiegler syndrome is an autosomal dominant tumor predisposition disorder. The disease is characterized by the occurrence of multiple skin appendage tumors, including cylindroma, trichoepithelioma, and spiradenoma. In some patients, tumors cover the entire head circumference, thereby causing disfigurement and other complications. Here, we report on a man with multiple cylindroma that were distributed in a turban tumor-like fashion. One of these neoplasms arose in the meatus externus of the right ear leading to unilateral hearing loss, a complication that has been documented only on few occasions in this disease.

Pilomatrical carcinoma: a case in a patient with HIV and hepatitis C.

Pilomatrical carcinoma is a rare tumor without a single pathognemonic feature that distinguishes it from the benign pilomatricoma. We report a 51-year-old man with HIV, hepatitis C, and pilomatrical carcinoma.

Trichilemmal carcinoma arising in seborrheic keratosis: a case report and published work review.

The secondary skin malignancies arising in seborrheic keratosis (SK) are uncommon, and the causal association between the pre-existing lesion and subsequent malignant transformation remains uncertain. Among these enigmatic conditions, trichilemmal differentiation and/or neoplasms in SK have rarely been reported thus far. Herein, we describe a case of invasive trichilemmal carcinoma arising in a long-standing SK of the abdominal skin, and clinicopathologically review this rare complication with a computerized medical published work search (PubMed) and citations from earlier reports. To our knowledge, only four cases of trichilemmal tumors arising in SK have been observed, and, interestingly, all cases, including ours, were Japanese. Four of five cases (80%) developed the tumors in non-sun-exposed SK, and indeed had no apparent actinic damage in the histology. The pre-existing SK itself is more likely to act as the primary pathogenic event for developing the secondary trichilemmal tumors than a coincidental phenomenon and a consequence of skin damage by cumulative sun exposure.

Eccrine porocarcinoma: a case with an obscure primary tumor diagnosed from lymph node metastasis.

Eccrine porocarcinoma (EPC), a rare malignant epidermal appendage tumor, is mainly seen in elderly patients. A long history is one of its main characteristics. Two types of EPC are known: juxtaepidermal and dermal. The juxtaepidermal type usually has a more aggressive behavior. Lymph node metastasis and high mitotic activity are associated with poor prognosis. A case of EPC with a long-standing but indolent primary site diagnosed from lymph node metastasis is presented here. There was also accompanying chronic dermatitis as a paraneoplastic syndrome. Diagnosing EPC prior to the regional lymph node involvement is the most valuable factor for a successful treatment. Persistent examinations and attempts to find the primary site(s) have to be made in such cases.

Synchronous microcystic adnexal carcinoma and gastric cancer with review of the literature.

A microcystic adnexal carcinoma (MAC) on the left lateral chest was synchronously accompanied by both an adenocarcinoma and a granular cell tumor of the stomach in a 70-year-old Japanese male. The MAC lesion had first appeared approximately 20 years earlier and had slowly increased without symptoms. After a definitive diagnosis was made by an excisional biopsy, a second operation was performed with wider excision, followed by split thickness skin grafting. Meanwhile, a punch biopsy from an erosive lesion, which was performed three days before the second operation, demonstrated gastric cancer. Consequently, a gastrectomy was undertaken 20 days later. The patient had since been followed for 2 years and 3 months without any sign of recurrence nor metastasis. Subsequently, soft lymph nodes in two regions of the left axilla were noticed. Three lymph nodes were excised for diagnostic purposes and found to be reactive hyperplasia without metastasis of skin tumor cells. To our knowledge, in the literature, 11 patients have been reported with MAC associated with double or multiple cancers which developed syn- or meta-chronously; ours is the 12th patient.

Microcystic adnexal carcinoma: an unusual cause of swelling and paraesthesia of the lower lip.

Microcystic adnexal carcinoma (MAC) is an uncommon, recently described, cutaneous adnexal malignant neoplasm, associated with significant morbidity as a consequence of its propensity for perineural invasion. The present report details the clinical and histological features of MAC in a young female presenting with lower labial swelling and paraesthesia.

Sebaceous carcinoma, trichoblastoma, and sebaceoma with features of trichoblastoma in nevus sebaceus.

A 73-year-old woman had a linear yellowish plaque on the upper part of her right ear since birth. She presented because of the sudden growth of a nodule within the plaque. The plaque was waxy and yellowish, arching around the upper part of the ear. A reddish to yellowish large nodule was seen within the central part of the arc-shaped plaque; in addition, a small pigmented nodule, a small skin-colored nodule, and a few pigmented papules were observed in the anterior half of the arched plaque. Histopathologic examination revealed the large nodule to be sebaceous carcinoma, the small pigmented nodule to be trichoblastoma, the small skin-colored nodule to be sebaceoma with the features of trichoblastoma, a few pigmented papules to be superficial trichoblastomas due to primitive follicular induction, and the linear yellowish plaque to be nevus sebaceus. Although our literature search revealed scanty reports of definite cases of sebaceous carcinoma in nevus sebaceus, the presented case demonstrated the occurrence of sebaceous carcinoma in nevus sebaceus. Malignant neoplasms occurring in nevus sebaceous seem to be extremely rare, but care should be taken when a large nodule suddenly grows in a lesion of nevus sebaceus, especially in older adults. The presented case also suggested a close relation between trichoblastoma and sebaceoma. The cytokeratin staining pattern could not distinguish between sebaceous and follicular neoplasms in our case.

Microcystic adnexal carcinoma associated with primary immunodeficiency, recurrent diffuse herpes simplex virus infection, and cutaneous T-cell lymphoma.

Cutaneous microcystic adnexal carcinoma (MAC) is a rare and poorly understood tumor that predominantly occurs in the head and neck. MAC usually affects people in their fourth and fifth decades. Some patients have had a history of radiation. We present a case of MAC occurring in the left antecubital fossa of an 18-year-old white woman with an unusual immunodeficiency syndrome. The patient also developed a squamous cell carcinoma, a cutaneous T-cell malignancy, and a perigastric leiomyoma. A congenital infection of herpes simplex virus (HSV) persisted throughout her life. The association of HSV infection with MAC and squamous cell carcinoma and that of peripheral T-cell lymphoma with Epstein-Barr virus is discussed in relation to her immunodeficiency.