Spitz tumors are melanocytic neoplasms characterized by specific, mutually exclusive driver molecular events, namely genomic rearrangements involving the threonine kinase BRAF and the tyrosine kinase receptors ALK , NTRK1 , NTRK2 , NTRK3 , MET , RET , ROS1 , and MAP3K8 or less commonly, mutations in HRAS or MAP2K1 . We hereby report 5 Spitz tumors with a SQSTM1::NTRK2 fusion. All patients were woman with the ages at diagnosis ranging from 30 to 50 years. Locations included the lower extremity (n = 3), forearm, and back (one each). All the neoplasms were superficial melanocytic proliferation with a flat to dome-shaped silhouette, in which junctional spindled and polygonal dendritic melanocytes were mainly arranged as horizontal nests associated with conspicuous lentiginous involvement of the follicular epithelium. Only one case showed heavily pigmented, vertically oriented melanocytic nests resembling Reed nevus. A superficial intradermal component observed in 2 cases appeared as small nests with a back-to-back configuration. In all lesions, next-generation sequencing analysis identified a SQSTM1::NTRK2 fusion. A single case studied with fluorescence in situ hybridization for copy number changes in melanoma-related genes proved negative. No further molecular alterations were detected, including TERT-p hotspot mutations.

• MeSH
• dospělí MeSH
• epiteloidní a vřetenobuněčný névus * genetika   MeSH
• hybridizace in situ fluorescenční MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory kůže * patologie   MeSH
• protoonkogenní proteiny genetika   MeSH
• sekvestosom 1 genetika   MeSH
• tyrosinkinasové receptory genetika   MeSH
• tyrosinkinasy genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé 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: Specific alterations involving MAPK genes (MAP3K8 fusions, MAP3K3 fusions) have been recently detected in a subgroup of spitzoid neoplasms that seem to constitute a distinctive clinicopathologic group, occur mostly in younger patients (median age 18 years) and present with atypical histologic features associated with frequent homozygous deletion of CDKN2A, qualifying a high proportion of them as Spitz melanoma (malignant Spitz tumor). Apart from lesions with spitzoid morphology harboring MAP3K8 or MAP3K3 fusion, a single case with MAP2K1 deletion has been identified. The authors report herein 4 melanocytic lesions with a MAP2K1 mutation, all showing similar microscopic appearances, including spitzoid cytology and dysplastic architectural features, resembling so-called SPARK nevus, suggesting that these lesions may represent another distinctive group.

• MeSH
• dospělí MeSH
• epiteloidní a vřetenobuněčný névus genetika   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• MAP kinasa-kinasa 1 genetika   MeSH
• melanom genetika   patologie   MeSH
• nádory kůže genetika   patologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH