Malignant melanoma arising in a burn scar.

Secondary malignancies are rare but devastating complications of longstanding burn scars. Squamous cell carcinoma is the most common, followed by basal cell carcinoma and melanomas. There are fewer than 50 total reported cases of malignant melanomas arising in burn scars. We report a case of malignant melanoma arising within a longstanding burn scar confirmed by histology, FISH, and PRAME staining to further characterize melanomas arising in burn scars and to illustrate the diagnostic challenges they present.

The Reemergence of Measles.

OBJECTIVES: Present-day pathologists may be unfamiliar with the histopathologic features of measles, which is a reemerging disease. Awareness of these features may enable early diagnosis of measles in unsuspected cases, including those with an atypical presentation. Using archived tissue samples from historic patients, a unique source of histopathologic information about measles and other reemerging infectious diseases, we performed a comprehensive analysis of the histopathologic features of measles seen in commonly infected tissues during prodrome, active, and late phases of the disease. METHODS: Subspecialty pathologists analyzed H&E-stained slides of specimens from 89 patients accessioned from 1919 to 1998 and correlated the histopathologic findings with clinical data. RESULTS: Measles caused acute and chronic histopathologic changes, especially in the respiratory, lymphoid (including appendix and tonsils), and central nervous systems. Bacterial infections in lung and other organs contributed significantly to adverse outcomes, especially in immunocompromised patients. CONCLUSIONS: Certain histopathologic features, especially Warthin-Finkeldey cells and multinucleated giant cells without inclusions, allow pathologists to diagnose or suggest the diagnosis of measles in unsuspected cases.

A Rare Case of Monomorphic T-Cell Posttransplant Lymphoproliferative Disorder Presenting as Primary Cutaneous Anaplastic Large Cell Lymphoma, ALK Negative.

ABSTRACT: Posttransplant lymphoproliferative disorders are a serious complication of hematopoietic and solid organ transplants secondary to iatrogenic immunosuppression. Most cases present as B-cell proliferations which are often Epstein-Barr virus positive; however, ∼10% of cases are T/NK cell and are less commonly associated with Epstein-Barr virus. Of these, cutaneous T/NK-cell lymphomas are exceedingly rare. We report a case of a 69-year-old male, liver transplant recipient who presented with a tender, bright red papule on the left arm during his annual skin cancer screening. Histopathologic evaluation revealed pleomorphic cells with enlarged nuclei, vesicular chromatin, and frequent mitotic figures, intercalating through the dermis. The tumor formed single strands and small cords without epidermal involvement. A patchy mild mixed inflammatory infiltrate was associated with the tumor. Tumor cells were CD2(+), CD4(+), CD30(+), CD3(-), CD20(-), ALK-1(-), and EBER(-). Molecular studies revealed a monoclonal T-cell receptor gamma gene rearrangement by polymerase chain reaction (PCR); ALK gene rearrangement was negative by fluorescence in situ hybridization (FISH). Taken together, the findings were consistent with an ALK-negative anaplastic large cell lymphoma involving skin, which, given the history of liver transplant, qualified as a monomorphic T-cell posttransplant lymphoproliferative disorder. Follow-up imaging studies showed no evidence of systemic disease, supporting an interpretation of primary cutaneous anaplastic large cell lymphoma.

Cutaneous Actinomycosis of the Perineum in an Immunocompetent Man.

ABSTRACT: We present a case of primary cutaneous actinomycosis of unclear pathogenesis. A 30-year-old-man with no significant medical or surgical history presented to the emergency department with a 2-week history of a tender perineal mass. The patient denied trauma or perforating injury to the area. Examination of the area revealed an indurated, nonfluctuant, erythematous papulonodule located 2 cm from the anus. The lesion was unresponsive to oral and topical antibiotics and was therefore excised. The excision specimen revealed a dense mixed infiltrate partially filling the reticular dermis and extending into the subcutaneous fat. The infiltrate surrounded grains of basophilic material with an outer rim of eosinophilic radiating Splendore-Hoeppli material. Within the grains, filamentous bacteria were highlighted with Periodic acid-Schiff and Grocott's methenamine silver. The organisms were gram-positive and acid-fast negative. Given the clinical and histopathologic findings, actinomycosis was diagnosed. Two weeks later, the patient reported resolution of symptoms. The patient was lost to follow-up. This case highlights an unusual presentation of actinomycosis and the crucial role histopathology plays in diagnosis.

Deep Penetrating Fibrous Histiocytoma: A Case Report and Implications for Surgical Management.

Deep penetrating fibrous histiocytoma (DPFH) is a rare variant of fibrous histiocytoma that can arise in the subcutis and deep soft tissues with different clinical implications from dermatofibromas. Dermatofibromas are mainly cosmetic annoyances and do not require surgical management. However, the DPFH does require that negative surgical margins be achieved because of the possibility of local recurrence and distant metastasis. We describe a case of a 24-year-old man diagnosed with DPFH through histologic examination and immunohistochemistry. The lesion displayed diffuse, strong D2-40 positivity and a minority of cells were highlighted with factor XIIIa. The lesion was negative for CD34. The patient's lesion was incompletely excised and a repeat excision was required.

Granular cell basal cell carcinoma: report of a case and review of the literature.

Granular cell basal cell carcinoma (BCC), characterized by large cells with abundant eosinophilic cytoplasm and conspicuous granularity, is an extremely rare variant of BCC with only 14 cases reported in the literature to date. A case of an 82-year-old man with clinically suspected BCC of the face is presented. Microscopic examination demonstrated characteristic morphologic and immunophenotypic features of granular cell BCC, as well as novel expression of p16 and lack of bcl-2 expression, both of which are previously undescribed in granular BCCs in the literature to date. Although very rare, this entity is important to include in the differential of any nodular cutaneous neoplasm with granular features. The rarity of this lesion makes immunohistochemistry especially helpful. As in other BCCs, granular cell BCCs typically strongly express Ber-EP4 and cytokeratins. The granular BCCs are characteristically periodic acid-Schiff positive, but show no expression of S100 protein. The rarity of the granular cell BCC and the aggressive biological behavior of the entities that may share similar histologic features make arriving at the correct diagnosis paramount to appropriate clinical management. The fifteenth case of granular cell BCC with subsequent review of the literature is reported, with particular focus on the immunohistochemical characteristics.

Cutaneous deciduosis: a report of two cases of an unusual pseudomalignancy.

Cutaneous deciduosis represents a rare manifestation of cutaneous endometriosis in which typical endometrial glands and stroma are morphologically and physiologically transformed under hormonal influence. The transformed glands and stroma usually take on the microscopic appearance of uterine decidua but may mimic malignancy. We describe two cases of cutaneous deciduosis that presented in the post-partum period, but biopsies were not performed until a much later date. The first lesion arose on the perineum of a 31-year-old female after vaginal delivery, but a biopsy was not performed until 6 years after presentation. The second lesion grew in a cesarean section scar of a 26-year-old female with a history of ovarian adnexal endometriosis. Clinically described as a persistent post-operative hematoma, the lesion throbbed in synchrony with her menstrual cycles; a biopsy was also performed 6 years after presentation. Histopathologically, both specimens showed similar findings. Sections showed a multinodular proliferation of pale-staining epithelioid cells without significant nuclear atypia or conspicuous mitotic figures. Both showed focal glands that ranged from slit-like to slightly dilated and that contained a flattened epithelial lining without atypia. These unusual cases are presented to instruct about the pathologic findings of this entity in order to prevent the unnecessary diagnosis of malignancy.

Pure apocrine nevus: a report of 4 cases.

Apocrine nevus is a rare tumor composed of increased mature apocrine glands and ductal structures within a fibrous stroma, located predominantly in the reticular dermis. They have been reported in association with apocrine carcinoma, extramammary Paget disease, and syringocystadenoma papilliferum; less commonly a pure apocrine nevus is identified, unassociated with another apocrine proliferation. Clinically apocrine nevi may appear as solitary or multiple nodules or plaques on the scalp, presternal skin, though they are seen most commonly in the axillae. We describe 4 cases of pure apocrine nevus, all of which appeared clinically as painless or mildly tender skin-colored axillary masses, 2 of which were bilateral. In each case, the lesions appeared in adulthood, and patients denied knowledge of congenital or childhood presence. Patients denied pruritis, discharge, bleeding, or antecedent trauma. Grossly, the specimens consisted of subcutaneous, multicystic ill-defined nodules. Biopsy showed prominent apocrine glands composed of irregularly columnar luminal cells with eosinophilic cytoplasm arranged in a somewhat organoid pattern filling the reticular dermis and extending into the subcutaneous adipose tissue. The glandular luminal cells displayed decapitation secretion. There was a paucity of pilosebaceous units. In one case, the overlying epidermis was papillomatous. The deepest portion of one specimen had lactational change simulating a lactational adenoma. No atypia was seen in either the glandular structures or the stroma. The adjacent sebaceous and eccrine structures were normal. The histologic features and immunohistochemical profile in relation to other apocrine lesions will be reviewed.

Hepatocellular carcinoma presenting as a precocious cutaneous metastasis.

The authors report a case of hepatocellular carcinoma (HCC) diagnosed by evaluation of a cutaneous metastasis in a patient without a prior diagnosis of HCC. Subsequent evaluation confirmed the presence of additional widespread metastatic disease. The medical literature is reviewed with regards to cutaneous metastasis, including precocious metastasis, of HCC. The pathologic evaluation of HCC is reviewed, including a discussion of the immunohistochemical profile of this malignancy and the utility of hepatocyte paraffin 1, CD10, and polyclonal carcinoembryonic antigen (pCEA) immunohistochemical stains.

Ink4a/arf deficiency promotes ultraviolet radiation-induced melanomagenesis.

Cutaneous malignant melanoma (CMM), already known for its highly aggressive behavior and resistance to conventional therapy, has evolved into a health crisis by virtue of a dramatic elevation in incidence. The underlying genetic basis for CMM, as well as the fundamental role for UV radiation in its etiology, is now widely accepted. However, the only bona fide genetic locus to emerge from extensive analysis of CMM suppressor candidates is INK4a/ARF at 9p21, which is lost frequently in familial and occasionally in somatic CMM. The functional relationship between INK4a/ARF and UV radiation in the pathogenesis of CMM is largely unknown. Recently, we reported that hepatocyte growth factor/scatter factor (HGF/SF)-transgenic mice develop melanomas after a single erythemal dose of neonatal UV radiation, supporting epidemiological data implicating childhood sunburn in CMM. Here we show that neonatal UV irradiation induces a full spectrum of melanocyte pathology from early premalignant lesions through distant metastases. Cutaneous melanomas arise with histopathological and molecular pathogenetic features remarkably similar to CMM, including loss of ink4a/arf. A role for ink4a/arf in UV-induced melanomagenesis was directly assessed by placing the HGF/SF transgene on a genetic background devoid of ink4a/arf. Median time to melanoma development induced by UV radiation was only 50 days in HGF/SF ink4a/arf(-/-) mice, compared with 152 and 238 days in HGF/SF ink4a/arf(+/-) and HGF/SF ink4a/arf(+/+) mice, respectively. These studies provide experimental evidence that ink4a/arf plays a critical role in UV-induced melanomagenesis and strongly suggest that sunburn is a highly significant risk factor, particularly in families harboring germ-line mutations in INK4a/ARF.