American Journal of Dermatopathology最新文献

{"title":"Pediatric Melanoma With a Rare BRAF V600K Mutation.","authors":"Pragya Singh, Daisy Wu, Arivarasan Karunamurthy, Brittani K N Seynnaeve","doi":"10.1097/DAD.0000000000002835","DOIUrl":"10.1097/DAD.0000000000002835","url":null,"abstract":"","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"162-164"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142300136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intramuscular Cellular Nodules in a Congenital Large Plaque-Like Blue Nevus: Melanoma or Not?","authors":"Rajalakshmi Tirumalae, Marjorie Correa, Suraj Manjunath","doi":"10.1097/DAD.0000000000002906","DOIUrl":"10.1097/DAD.0000000000002906","url":null,"abstract":"<p><strong>Introduction: </strong>Melanoma arising in blue nevus (BN) is usually evident on histopathology. However, there are cases in the gray zone where neither morphology nor immunostains and molecular studies are conclusive.</p><p><strong>Case report: </strong>A 33-year-old man presented with greenish discoloration of the abdominal skin at birth. Over time, the lesion increased in size to involve the entire left half of the abdomen, extending to the back and chest wall. He noticed nodules beneath the lesion, which were enlarging. Magentic resonanace imaging showed a lesion within the left external oblique measuring 8.3 × 6 × 4 cm and smaller lesions in the adjacent muscular planes. Gross examination of the excision showed an 8 × 6.5 × 5 cm brown-black, intramuscular nodule. Histopathology showed a BN of the overlying skin extending into the subcutis. The intramuscular nodule showed infiltrative, cellular areas with nonpigmented, plump spindle cells in nests and pseudorosettes with focal necrosis. There was minimal pleomorphism and prominent eosinophilic nucleoli. Mitoses were scarce. The neoplastic cells expressed Melan A, S100, and HMB45 with a low proliferative index (<1%). The lack of atypia and mitoses, despite clinically suspicious for melanoma, lead us to perform comparative genomic hybridization, which showed an abnormality suggesting malignancy. The patient remains with localized disease 6 years after surgery and no distant metastases.</p><p><strong>Conclusions: </strong>Cellular nodules in a plaque-like blue nevus presenting as an intramuscular mass is hitherto unreported. It is prudent to follow-up such cases like a melanoma, despite lacking overt atypia and mutations, because metastases have been reported as late as 16 years after diagnosis.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"128-132"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142958116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sebaceous Carcinoma Arising in a Precursor Benign Sebaceoma: Rare Example Highlighting the Utility of Immunohistochemistry Including p53.","authors":"Maged Daruish, Olubanji Oguntunde, Martyn Richards, Saleem Taibjee","doi":"10.1097/DAD.0000000000002858","DOIUrl":"10.1097/DAD.0000000000002858","url":null,"abstract":"<p><strong>Abstract: </strong>Reports of sebaceous carcinoma arising from a pre-existing benign precursor are extremely sparse in the literature. We describe a case in which there was clear transition between sebaceoma and sebaceous carcinoma, with a different pattern of p53 staining in each component.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"e27-e30"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142928563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Primary Epithelioid Angiosarcoma of the Penis: A Case Report With a Brief Review of the Literature.","authors":"Valentina Caputo, Gerardo Cazzato, Lucia Brambilla, Franco Rongioletti","doi":"10.1097/DAD.0000000000002888","DOIUrl":"https://doi.org/10.1097/DAD.0000000000002888","url":null,"abstract":"<p><strong>Abstract: </strong>Angiosarcoma of the penis is an exceptionally rare mesenchymal tumor, with only about 30 cases documented in the literature. Because of its rarity and the often nonspecific clinical presentation, histopathological examination plays a critical role in accurate diagnosis. Angiosarcoma of the penis typically arises in the corpus cavernosum but has also been reported in the glans and urethra, often presenting with metastases. This report details a case of epithelioid angiosarcoma of the penis in an 84-year-old man, who presented with a rapidly enlarging, violaceous nodule on the glans penis. Histopathology revealed atypical epithelioid endothelial cells with pleomorphism and mitotic activity, and immunohistochemical markers such as CD31, Erythroblast transformation-specific [ETS]-related gene, and cellular myelocytomatosis oncogene confirmed the malignant endothelial neoplasm. The differential diagnosis excluded conditions such as epithelioid hemangioendothelioma and Kaposi sarcoma. Because of the rarity, standardized treatment protocols are lacking; however, wide excision with tumor-free margins and the potential for targeted therapies based on gene amplification are considered important. The review highlights the diagnostic challenges, prognostic factors, and current therapeutic approaches, emphasizing the need for further research to develop standardized treatment protocols.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":"47 2","pages":"e23-e26"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143034726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Case Series of Primary Cutaneous Sarcomatoid Carcinoma With Aberrant Smooth Muscle Actin Expression: A Clinicopathologic and Immunophenotypic Study.","authors":"Saba Shafi, Alejandro A Gru, Jorge Roman, Jessica Maupin, Jose A Plaza","doi":"10.1097/DAD.0000000000002800","DOIUrl":"10.1097/DAD.0000000000002800","url":null,"abstract":"<p><strong>Abstract: </strong>Primary cutaneous sarcomatoid squamous cell carcinoma can show significant histologic overlap with other malignant spindle cell tumors, posing a diagnostic challenge. Even with a wide array of immunohistochemical markers, the exact line of differentiation can be a challenge to identify in some cases. The picture is further complicated by the aberrant expression of myofibroblastic markers [such as smooth muscle actin (SMA)] by these neoplasms, along with a concomitant loss of conventional epithelial markers. The histologic differential diagnoses of primary cutaneous sarcomatoid squamous cell carcinoma include desmoplastic melanoma, leiomyosarcoma, and spindle cell atypical fibroxanthoma/pleomorphic dermal sarcoma (AFX/PDS). A retrospective analysis of 16 cases of PCSSCCs with SMA expression, obtained from large academic institutions, was performed and is summarized below. The tumors were in the scalp (6 cases), arm (4 cases), leg (2 cases), face (2 cases), hand (1 case), and neck (1 case). Immunohistochemical studies were performed in all cases with the following antibodies: AE1/AE3, CAM 5.2, MNF-116, p63, p40, CK5/6, S-100, SOX10, SMA, desmin, calponin, H-caldesmon, CD10, CD68, CD163, and CD34. Histopathologically, all cases were classified as high-grade malignant poorly differentiated neoplasms. Tumors were characterized by an infiltrative neoplasm that involved the entire reticular dermis and, in 7 cases, the subcutaneous fat. Three cases were associated with a well-differentiated squamous cell component. The neoplasms were composed of atypical spindle and epithelioid cells arranged in long and intersecting fascicles. All neoplasms were positive for epithelial markers (at least 1 marker), and all cases were strongly positive for SMA. Our data emphasize the diagnostic utility of multiple epithelial markers as a first screening tool in the detection and workup of malignant cutaneous sarcomatoid neoplasms. Awareness of SMA expression in these tumors can complicate its diagnosis, and it is important to recognize this aberrant immunophenotype to facilitate definitive diagnosis and avoid misdiagnosis.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"83-92"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141983798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ossifying Panniculitis Presenting as a Painful Nodule on the Abdomen.","authors":"Rosemary Oaks, Abigail Beard, Richard Miller, Keith Baribault","doi":"10.1097/DAD.0000000000002884","DOIUrl":"10.1097/DAD.0000000000002884","url":null,"abstract":"<p><strong>Abstract: </strong>Myositis ossificans is a benign ossifying nodule that can affect any type of tissue but is most commonly found in muscle. Occurrence in the soft tissue of the subcutis is less common and has been referred to as panniculitis ossificans. In this case report, we describe a 46-year-old woman who presented with a 1.7 × 2.0 cm lesion on the abdomen that had been present for several months, was painful, and easily irritated by clothing. Initial clinical assessment based on history and physical examination was an epidermal cyst and removal by excision was performed. Initial histologic findings showed a spindle cell proliferation in the subcutis along with bone formation. Osteoblasts were noted to be rimming the bone and giant cells were present. The spindle cells were SMA positive and partially factor XIIIa positive while S100 protein staining was negative, confirming the diagnosis of panniculitis ossificans.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"93-94"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142584971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential Expression of p53 in Mycosis Fungoides, Sezary Syndromes, and Their Transformed Forms.","authors":"Anna Courtois, Pierre Allaume, Maxime Raby, Cédric Pastoret, Catherine Droitcourt, Cécile Le Naourès, Henri Adamski, Alain Dupuy, François Le Gall, Solène-Florence Kammerer-Jacquet","doi":"10.1097/DAD.0000000000002898","DOIUrl":"10.1097/DAD.0000000000002898","url":null,"abstract":"<p><strong>Abstract: </strong>Mycosis fungoides (MF) and Sezary syndrome (SS) are common entities among primary cutaneous lymphomas. Large cell transformation is challenging for diagnosis and therapy. Molecular mechanisms by which these lymphomas undergo this transformation are poorly defined. We studied the immunohistochemical status of p53 in these entities and assessed whether p53 expression could be a useful tool for diagnosis and assessment of transformation. We extracted patients with transformed and untransformed SS or MF from the French Study Group on Cutaneous Lymphoma database between 2014 and 2021, followed in the Rennes University Hospital. An immunohistochemical study of p53 expression was performed on the biopsies sampled as part of routine care. We compared p53 overexpression in the different groups. We included 25 patients with MF, 7 patients with transformed MF (T-MF), 11 patients with SS, and 5 patients with transformed SS (T-SS). Using a cut-off set at 30% expression of neoplastic cells, we noted an overexpression of p53 in T-MF and T-SS compared with nontransformed forms (47% vs. 12%, respectively, P < 0.01) and in MF compared with SS (23% vs. 7%, respectively, P < 0.01). Overexpression of p53 with a cut-off at 30% therefore seems to be a discriminating tool in the differential diagnosis of MF/SS versus their transformed forms as well as the differential diagnosis between MF and SS.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"95-104"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142808317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunohistochemistry for Immunoglobulin G4 on Paraffin Sections as a Diagnostic Test for Pemphigus.","authors":"Tsvetana I Abadjieva, Sylvia N Genova, Mina M Pencheva, Zhaneta H Zhelyazkova","doi":"10.1097/DAD.0000000000002885","DOIUrl":"10.1097/DAD.0000000000002885","url":null,"abstract":"<p><strong>Abstract: </strong>Pemphigus is a group of autoimmune bullous diseases mediated by autoantibodies most often of the immunoglobulin G class, subclasses immunoglobulin G1, and immunoglobulin G4 (IgG4), directed against desmosomal adhesion proteins of keratinocytes. This study aimed to evaluate IgG4 immunoreactivity on paraffin sections using immunohistochemistry in patients with pemphigus as a diagnostic test. Fifty formalin-fixed paraffin-embedded specimens from patients with pemphigus were selected. Fifty formalin-fixed paraffin-embedded specimens from patients with bullous diseases other than pemphigus were used as controls. Biopsies were performed on active lesions in newly diagnosed patients. Immunohistochemistry for IgG4 was performed on paraffin sections with an anti-immunoglobulin G4 antibody. Positivity was defined as distinctive, uninterrupted immunoreactivity localized to the intercellular junctions of keratinocytes. A finding that did not meet these criteria was defined as negative. Forty-three (86.0%) of the examined patients had pemphigus vulgaris and 7 (14%) had pemphigus foliaceus. Forty-nine (98.0%) specimens from patients with pemphigus were immunoreactive for IgG4, 1 (2%) upper back biopsy from the patient with oral pemphigus showed negative immunoreactivity for IgG4. Negative immunoreactivity was found in 45 (90%) controls. Five (10%) controls with bullous pemphigoid showed immunoreactivity for IgG4. Sensitivity of the method was established to be 98% and specificity 90%. Immunohistochemical examination for IgG4 for the diagnosis of pemphigus can be applied when direct immunofluorescence examination is unavailable. The advantage of this method is that it does not require special equipment and the histology slides are permanent.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":"47 2","pages":"110-113"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11761055/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143034698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Secondary Syphilis Presenting With an Interstitial Granuloma Annulare-Like Histopathologic Pattern: A Report of 2 Cases.","authors":"David Afonso João, Tamás Pancsa, Peter Kicko, Eliška Langerová, Radek Šíma, Jana Hercogová, Alena Skálová, Michal Michal, Denisa Kacerovská","doi":"10.1097/DAD.0000000000002879","DOIUrl":"https://doi.org/10.1097/DAD.0000000000002879","url":null,"abstract":"<p><strong>Abstract: </strong>Syphilis, known as \"the great mimicker,\" is caused by the spirochete Treponema pallidum and is characterized by a diverse array of clinical and histopathologic presentations. In secondary cutaneous syphilis, the most consistent morphological features include a superficial and deep perivascular infiltrate containing plasma cells, varying degrees of endothelial swelling, irregular acanthosis, elongation of rete ridges, a vacuolated pattern, and the presence of plasma cells. Although serologic tests are essential for definitive diagnosis, spirochetes can sometimes be directly identified in silver-stained tissue slides or through immunohistochemistry. Granuloma annulare is a relatively common, benign, self-limiting condition with 3 main variants: conventional, subcutaneous, and interstitial, each with distinct characteristics. In this study, we report 2 cases of cutaneous secondary syphilis with a striking granulomatous reaction pattern that closely mimics the interstitial variant of granuloma annulare. Owing to the severity of the tertiary stage of syphilis, distinguishing between these 2 entities is crucial.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":"47 2","pages":"122-127"},"PeriodicalIF":1.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143034728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Digital Pathology and Light Microscopy Among Dermatology Residents: A Reappraisal Following Practice Changes.","authors":"Donald E Neal, Emma F Johnson, Shruti Agrawal, Austin Todd, Michael J Camilleri, Carilyn N Wieland","doi":"10.1097/DAD.0000000000002805","DOIUrl":"10.1097/DAD.0000000000002805","url":null,"abstract":"<p><strong>Background: </strong>Following transition to digital pathology for primary diagnosis at our institution, dermatology residents have reduced exposure to light microscopy. This study compares resident competency with light microscopy versus digital pathology following practice changes.</p><p><strong>Methods: </strong>Twenty-one dermatology residents were administered a dermatopathology examination composed of 32 diagnoses evaluated using digital slides and 32 with light microscopy. Case difficulty was graded and balanced between modalities. Diagnostic accuracy was measured using the number of correct diagnoses for each modality. Participants were surveyed regarding their experience and preferences.</p><p><strong>Results: </strong>Diagnostic accuracy was higher with digital pathology than light microscopy (22/32 vs. 18/32, P < 0.001). Diagnostic accuracy with digital pathology increased with years of training, but accuracy with light microscopy did not. Residents with previous light microscopy experience achieved an average score of 19/32 on glass, as compared with 10/32 for those without experience ( P = 0.039). Digital pathology was preferred over light microscopy (18/21, 85.7%).</p><p><strong>Conclusions: </strong>Trainees had better diagnostic proficiency with digital pathology and preferred this modality. Most practices at this time continue to use light microscopy. Therefore, we need to maintain proficiency in microscopy during training while concurrently preparing trainees for a digital future.</p>","PeriodicalId":50967,"journal":{"name":"American Journal of Dermatopathology","volume":" ","pages":"25-29"},"PeriodicalIF":1.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141983804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}