Urticarial mycosis fungoides: A distinctive presentation with blood involvement and a peculiar immunophenotype.

Mycosis fungoides (MF) has been widely reported to mimick a considerable number of different dermatoses, including scarring alopecia, bullous dermatoses or cysts, and comedones. In atypical presentations, histopathology is essential for the diagnosis. We present two cases of MF with clinical urticarial lesions and a striking blood involvement that responded to mogamulizumab treatment.

Cerebellar metastasis of a Liposarcoma: Case report and literature review.

Background: Liposarcoma (LPS) is a rare type of tumor; they come from the adipose tissue. It is the most common type of soft-tissue sarcoma. Every type of LPS has morphological features, immunophenotypic, and molecular pathogenesis characteristics of their own.

Cutaneous eruption with reactive endothelial atypia due to emerging targeted cancer therapies: Report of two cases with clinico-pathologic correlation.

Targeted anticancer therapy is being used with greater frequency and dermatologic toxicities are among the most frequent adverse events of these drugs. However, histopathological features of these adverse events are not yet well characterized. We present two cases of clinically different cutaneous toxicities on two patients with hematologic neoplasia.

Toker cell hyperplasia in Zuska disease: A tricky association.

Toker cells (TCs) are sometimes present in the nipple epidermis as oval cells with pale cytoplasm and roundish nuclei. In most cases, TCs may be easily distinguished from cancerous cells of Paget disease of the nipple (PCs). Especially in TC hyperplasia, in which mild-to-moderate atypia may be present, it may be challenging to distinguish between TCs and PCs.

Three additional cases of non-neural granular cell tumor with novel immunohistochemical findings.

Background: Non-neural granular cell tumor (NNGCT) is an uncommon neoplasm of controversial histogenesis and its histopathologic differential diagnosis includes, in addition to conventional GCT, other dermal tumors that may exhibit granular cell change.

Methods: Three patients with a diagnosis of NNGCT were identified in the authors' files. Hematoxylin and eosin-stained sections and immunohistochemical studies were performed.

Acrolocalized variant of lichen sclerosus initially manifesting as degenerative collagenous plaques of the hands.

Lichen sclerosus involving the hands is very uncommon. On the other hand, degenerative collagenous plaques of the hands is a rare condition characterized by keratotic, translucent papules in linear array, on the radial border of the hands. Histopathologically, lesions of degenerative collagenous plaques of the hands show increased collagen bundles in upper half of the dermis and dermal elastosis.

Syringocystadenoma papilliferum associated with verrucous carcinoma of the skin in the same lesion: Report of four cases.

The association of syringocystadenoma papilliferum (SCAP) with verrucous carcinoma (VC) of the skin in the same lesion is a rare, but well-documented event. Although human papillomaviruses (HPV) have been proposed to have an etiologic role in the development of the verrucous proliferations associated with SCAP, most of the immunohistochemical and molecular studies have failed to show the presence of their genomic material in these lesions. We report a series of four cases of SCAP associated with VC in anogenital lesions.

Langerhans cell histiocytosis and multiple reticulohistiocytomas in a patient with TAR syndrome: An association not previously described.

We describe a patient with thrombocytopenia-absent radius (TAR) syndrome, multisystemic Langerhans cell histiocytosis and multiple reticulohistiocytomas. A mutational study by massive sequencing identified the Val600Glu (V600E) BRAF mutation in the Langerhans cell histiocytosis lesions, but no molecular alterations were found in the reticulohistiocytoma lesions. The concomitant presence in the same patient of more than one type of histiocytosis from two different groups recognized in the most recent Histiocyte Society classification is an extremely rare event.

Dermal Hyperneury and Multiple Sclerotic Fibromas in Multiple Endocrine Neoplasia Type 2A Syndrome.

Importance: Multiple endocrine neoplasia type 2 (MEN 2) syndrome is an autosomal dominant, hereditary cancer disorder caused by germline mutations in the RET (formerly MEN2A, MEN2B) proto-oncogene located on chromosomal band 10q11.21. Two distinct clinical forms have been described as the following phenotypes: multiple endocrine neoplasia type 2A (MEN 2A) and multiple endocrine neoplasia type 2B (MEN 2B) syndromes.

Carcinoma hemorrhagiectoides: case report of an uncommon presentation of cutaneous metastatic breast carcinoma.

In most cases, cutaneous metastases develop after the diagnosis of the primary internal malignancy has been established, but sometimes they can be discovered earlier or simultaneously. We describe a case of a 90-year-old woman who presented to the emergency room in poor general condition, with cutaneous lesions characterized by hot, infiltrated, violaceous and erythematous plaques involving the left chest wall. The clinical and histopathological findings were consistent with the recently described variant of inflammatory cutaneous metastatic carcinoma named carcinoma hemorrhagiectoides.

Plaque-Like Pilar Sheath Acanthoma: Histopathologic and Immunohistochemical Study of 3 Unusual Cases.

Pilar sheath acanthoma is an uncommon, benign follicular neoplasm that frequently presents as a solitary lesion. This neoplasm usually appears on the skin around the upper lip of elderly patients. Histopathologically, the neoplasm usually shows a cystic configuration with epithelial lobules resembling to those of the outer root sheath of the hair follicle at the level of the isthmus emanating radially from the cyst wall.

Genital folliculo-sebaceous cystic hamartoma: A claim of the stroma as a clue in the diagnosis of proliferations with follicular differentiation.

Folliculo-sebaceous hamartomas comprise a series of entities whose boundaries are imprecise. We present the clinical case of a folliculo-sebaceous cystic hamartoma of genital localization where the diagnosis was established based on the epithelial proliferation, but mostly, on the characteristic stroma. Because this lesion lacked of the cystic component, we mention the most frequent differential diagnoses and review the literature of the few cases published on this infrequent localization.