Cuticular poroma is a rare variant of poroma composed of exclusively or predominantly cuticular cells, namely of large cells with ample eosinophilic cytoplasm. We report 7 cases of this rare tumor identified among 426 neoplasms diagnosed as poroma or porocarcinoma. The patients were 4 males and 3 females, ranging in age from 18 to 88 years. All presented with a solitary asymptomatic nodule. The location included knee (2 cases), shoulder, thigh, shin, lower arm, and neck (each 1). All lesions were surgically removed. No evidence of disease was observed in 5 patients with available follow-up (range 12-124 months).Microscopically, all neoplasms were composed of variably sized, focally closed packed, or interconnecting nodules constituted mostly of cuticular cells. Small poroid cells were a focal feature in 5 tumors, whereas in the remaining 2 cases, poroid cells with conspicuous but still in minority. Five neoplasms were somewhat asymmetric, with irregular outlines. Ductal differentiation and intracytoplasmic vacuoles were seen in 6 tumors. Other features variably encountered were conspicuous intranuclear pseudoinclusions, cystic change, occasional multinucleated cells, increased mitoses, and stromal desmoplasia. Four of the 5 tumors analyzed with next-generation sequencing yielded YAP1::NUTM1 fusions. In addition, various mutations, mostly of unknown significance were identified in one neoplasm.

• MeSH
• dospělí MeSH
• ekrinní porokarcinom * genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádory potních žláz * genetika   patologie   MeSH
• porom * genetika   patologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BAP1-inactivated melanocytic tumor (BIMT) is a group of melanocytic neoplasms with epithelioid cell morphology molecularly characterized by the loss of function of BAP1, a tumor suppressor gene located on chromosome 3p21, and a mutually exclusive mitogenic driver mutation, more commonly BRAF. BIMTs can occur as a sporadic lesion or, less commonly, in the setting of an autosomal dominant cancer susceptibility syndrome caused by a BAP1 germline inactivating mutation. Owing to the frequent identification of remnants of a conventional nevus, BIMTs are currently classified within the group of combined melanocytic nevi. "Pure" lesions can also be observed. We studied 50 BIMTs from 36 patients. Most lesions were composed of epithelioid melanocytes of varying size and shapes, resulting extreme cytomorphological heterogeneity. Several distinctive morphological variants of multinucleated/giant cells were identified. Some hitherto underrecognized microscopic features, especially regarding nuclear characteristics included nuclear blebbing, nuclear budding, micronuclei, shadow nuclei, peculiar cytoplasmic projections (ant-bear cells) often containing micronuclei and cell-in-cell structures (entosis). In addition, there were mixed nests of conventional and BAP1-inactivated melanocytes and squeezed remnants of the original nevus. Of the 26 lesions studied, 24 yielded a BRAF mutation, while in the remaining two cases there was a RAF1 fusion. BAP1 biallelic and singe allele mutations were found in 4/22 and 16/24 neoplasms, respectively. In five patients, there was a BAP1 germline mutation. Six novel, previously unreported BAP1 mutations have been identified. BAP1 heterozygous loss was detected in 11/22 lesions. Fluorescence in situ hybridization for copy number changes revealed a related amplification of both RREB1 and MYC genes in one tumor, whereas the remaining 20 lesions studied were negative; no TERT-p mutation was found in 14 studied neoplasms. Tetraploidy was identified in 5/21 BIMTs. Of the 21 patients with available follow-up, only one child had a locoregional lymph node metastasis. Our results support a progression of BIMTs from a conventional BRAF mutated in which the original nevus is gradually replaced by epithelioid BAP1-inactivated melanocytes. Some features suggest more complex underlying pathophysiological events that need to be elucidated.

• MeSH
• dítě MeSH
• epiteloidní a vřetenobuněčný névus * genetika   MeSH
• hybridizace in situ fluorescenční MeSH
• lidé MeSH
• nádorové supresorové proteiny genetika   MeSH
• nádory kůže * genetika   patologie   MeSH
• névus * MeSH
• pigmentový névus * genetika   patologie   MeSH
• protoonkogenní proteiny B-raf genetika   MeSH
• thiolesterasa ubikvitinu genetika   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

ABSTRACT: Trichoblastoma (TB) is a benign biphasic follicular neoplasm with differentiation toward the germinative cells and a specific follicular mesenchyme. We subtyped 349 sporadic TB according to a classification proposed by Ackerman. Two hundred forty-six (246/349, 70.5%) neoplasms were comprised of mixed subtypes. TB composed exclusively of a single pattern was less common (103/349, 29.5%). The most common pure subtype was cribriform TB followed by small nodular TB. Twelve cases (12/349, 3.4%) had unique features and are reported herein as novel histopathologic subtypes of the neoplasm.

• MeSH
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• nádory kožních adnex patologie   MeSH
• nádory kůže patologie   MeSH
• nemoci vlasů patologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• vlasový folikul patologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Lichen aureus is a variant of pigmented purpuric dermatoses. The usual histopathology of lichen aureus is characterized by a subepidermal dense, band-like lymphocytic infiltrate, extravasated erythrocytes, and hemosiderin deposits. We report three patients with lichen aureus on the extremities with similar clinical, dermoscopic, and histopathological findings characterized by a dense band-like relatively deep dermal infiltrate accompanied by extravasation of erythrocytes and hemosiderin deposits occasioning a resemblance to a lymphoproliferative disorder.

• MeSH
• dermatoskopie metody   MeSH
• diferenciální diagnóza MeSH
• dospělí MeSH
• erytrocyty patologie   MeSH
• hemosiderin analýza   MeSH
• imunohistochemie metody   MeSH
• kožní nemoci patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lymfocyty patologie   MeSH
• lymfoproliferativní nemoci metabolismus   patologie   MeSH
• plazmatické buňky patologie   MeSH
• poruchy pigmentace patologie   MeSH
• pseudolymfom komplikace   patologie   MeSH
• purpura diagnóza   patologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

ABSTRACT: Sebaceous neoplasms occur sporadically or in the setting of Muir-Torre syndrome. The data regarding the correlation of pathologic features and DNA mismatch repair (MMR) staining pattern in sebaceous tumors of the skin are very scanty and based on relatively small series of patients. The goal of this study was to correlate MMR staining pattern with selected morphological features in a series of 145 sebaceous neoplasms (sebaceous adenoma, sebaceoma, and extraocular sebaceous carcinoma) from 136 patients. Cystic change, intratumoral mucin deposits, squamous metaplasia in the absence of keratoacanthoma-like changes, ulceration, intratumoral and peritumoral lymphocytes (in cases without epidermal ulceration), and intertumoral heterogeneity proved to be significantly associated with MMR deficiency. Identification of any of these changes, alone or in combination, should prompt further investigation of the patient to exclude Muir-Torre Syndrome. Our study also confirms the previously published observation that the diagnosis and tumor location are significantly associated with MMR deficiency.

• MeSH
• adenom metabolismus   patologie   MeSH
• DNA vazebné proteiny metabolismus   MeSH
• dospělí MeSH
• homolog 2 proteinu MutS metabolismus   MeSH
• imunohistochemie MeSH
• karcinom metabolismus   patologie   MeSH
• končetiny MeSH
• lidé středního věku MeSH
• lidé MeSH
• mismatch repair endonukleáza PMS2 metabolismus   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• MutL homolog 1 metabolismus   MeSH
• nádory hlavy a krku metabolismus   patologie   MeSH
• nádory mazových žláz metabolismus   patologie   MeSH
• obličej MeSH
• oprava chybného párování bází DNA MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• skalp MeSH
• trup MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH