American Journal of Surgical Pathology最新文献

{"title":"Histopathologic Grading of Residual Tumor Predicts Survival of Intrahepatic Cholangiocarcinoma Patients Treated With Neoadjuvant Therapy: Major Pathologic Response and Its Clinical Significance.","authors":"Gaohua Wu, Xiufen Chen, Rongkui Luo, Ye Xin Koh, Tony Kiat Hon Lim, Valerie Chew, Jian Zhou, Jia Fan, Qiang Gao, Kai Zhu, Ruoyu Shi","doi":"10.1097/PAS.0000000000002359","DOIUrl":"10.1097/PAS.0000000000002359","url":null,"abstract":"<p><p>Neoadjuvant therapy (NAT) is increasingly used to treat patients with initially unresectable intrahepatic cholangiocarcinoma (iCCA). A histopathologic grading system for residual tumors that can predict patient survival is lacking in the literature. This retrospective study enrolled 151 iCCA patients who received NAT. The percentage of residual viable tumor (%RVT) extent was calculated by RVT surface area/total tumor bed area ×100 and scored in 5% increments. Kaplan-Meier and Cox regression analyses were used to investigate its correlations with recurrence-free survival (RFS) and overall survival (OS). Tumor regression grading by the College of American Pathologists (CAP) and MD Anderson (MDA) methodologies were also validated. A 10% RVT-based tumor regression score (TRS) showed a significant correlation with both OS and RFS. TRS and major pathologic response (mPR) were therefore defined as follows: TRS 1/mPR, tumor with 0 to 10% RVT; TRS 2, more than 10% RVT. Patients graded as TRS 1/mPR had superior OS ( P =0.006) and RFS ( P <0.001) compared with those with TRS 2 in univariate analysis. In a multivariate analysis including ypTNM stages, lymphovascular invasion, and perineural invasion, TRS 1/mPR was also found to be an independent prognostic factor for both OS (hazard ratio [HR]: 0.226; 95% CI: 0.053-0.966, P =0.045) and RFS (HR: 0.474; 95% CI: 0.231-0.974, P =0.042). As for the CAP and MDA grading methodologies, they were found to correlate with RFS (CAP: P =0.002; MDA: P =0.001), but not with OS (CAP: P =0.181; MDA: P =0.09). Our study revealed that a TRS of ≤10% RVT significantly correlates with longer OS and RFS and can be suggested as an mPR in iCCA. This indicator is easily applicable, prognostically relevant, and could be further validated in future prospective clinical trials.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"578-587"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12068548/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143655910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expanding Insights Into PRAME Expression in Merkel Cell Carcinoma.","authors":"Jesús Machuca-Aguado, Rosa Rendón-García, Juan José Ríos-Martín","doi":"10.1097/PAS.0000000000002346","DOIUrl":"10.1097/PAS.0000000000002346","url":null,"abstract":"","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"635-637"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142880816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Malignant Giant Cell Tumor of Bone: A Clinicopathologic Series of 28 Cases Highlighting Genetic Differences Compared With Conventional, Atypical, and Metastasizing Conventional Tumors.","authors":"David J Papke, S Krisztian Kovacs, Igor Odintsov, Jason L Hornick, Kevin A Raskin, Erik T Newman, Santiago Lozano-Calderón, Ivan Chebib, Yin P Hung, G Petur Nielsen","doi":"10.1097/PAS.0000000000002387","DOIUrl":"10.1097/PAS.0000000000002387","url":null,"abstract":"<p><p>Giant cell tumors of bone are locally aggressive, frequently harbor H3F3A p.G34W mutations, and rarely undergo malignant transformation. The pathogenesis of malignant transformation remains incompletely characterized. Herein, we present 28 malignant giant cell tumors of bone from 14 males and 14 females, aged 16 to 65 (median 39) years. Primary sites included long bones (n=20), pelvis (n=3), vertebrae (n=2), and rarely rib, phalanx, and cuneiform (n=1 each). Sixteen (62%) of 26 tumors with available history represented malignant transformation or recurrence of conventional giant cell tumors of bone, at intervals of 1.3 to 35 (median 7.3) years before malignant transformation. Eight of 15 patients with available treatment history received denosumab before a diagnosis of malignancy. Ten (38%) of 26 tumors with available history likely arose de novo, including 7 with conventional areas and 3 H3F3A -mutant sarcomas lacking conventional giant cell tumor of bone. Of 28 malignant giant cell tumors of bone, 18 (64%) and 10 (36%) harbored osteoblastic and chondroblastic elements, respectively. Among 23 tumors with available genetic testing or surrogate immunohistochemistry, 17 (74%) were p.G34W-mutant, whereas other tumors carried H3F3A p.G34L (n=2), p.G34V (n=2), and p.G34R (n=1) alterations; 1 tumor harbored H3F3B p.K116E and p.R117S in cis. Seven (70%) of 10 malignant giant cell tumors of bone showed complex copy number alterations by single nucleotide polymorphism (SNP) array, DNA next-generation sequencing (NGS), and/or karyotype analysis. In contrast, complex chromosomal alterations were lacking in 32 conventional giant cell tumors of bone tested (24 by karyotype, 7 by SNP array, 1 by DNA NGS), 3 atypical giant cell tumors of bone with isolated marked nuclear atypia (2 by karyotype, 1 by SNP array) and 3 metastasizing conventional giant cell tumors of bone (2 by DNA NGS, 1 by karyotype). Clinical follow-up was available for 20 patients (71%), and one additional patient had metastases at presentation. Overall, 14 of 21 patients (67%) developed metastases, and 10 of 20 patients with follow-up (50%) died of disease at 2 months to 9.6 years (median 7 mo). Most patients were treated with chemotherapy; 1 patient (PD-L1 TPS >95%) was treated with pembrolizumab, with complete clinical response of metastatic disease at 2.5 years. In conclusion, malignant giant cell tumors of bone typically arise from long bones, harbor osteosarcomatous and/or chondrosarcomatous differentiation, and show significant risk for distant metastasis and demise. Our data suggest that copy number analysis may be useful in distinguishing malignant giant cell tumors of bone from their conventional, atypical, and metastasizing conventional counterparts.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"539-553"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143613043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expanding the Molecular-genetic Spectrum of Canalicular Adenoma-like Subtype of Pleomorphic Adenoma of Salivary Glands.","authors":"Natálie Klubíčková, Frederica Loghides, Mari F C M van den Hout, Valérie Costes-Martineau, Gerardo Ferrara, Miguel Rito, Veronika Hájková, Petr Grossmann, Petr Šteiner, Inka Kovářová, Michal Michal, Ilmo Leivo, Alena Skálová","doi":"10.1097/PAS.0000000000002377","DOIUrl":"10.1097/PAS.0000000000002377","url":null,"abstract":"<p><p>Canalicular tumors of the salivary glands have recently emerged as an entity characterized by distinct morphology and recurrent HMGA2 gene rearrangement. In this study, we analyzed 40 cases intending to elucidate their features further. The monophasic or biphasic tumors exhibited a growth pattern of interconnected anastomosing trabeculae and canaliculi, accompanied by a classical pleomorphic adenoma in one-third of the cases. Invasive growth into surrounding adipose tissue was revealed in one case which was, therefore, diagnosed as epithelial-myoepithelial carcinoma. Although the tumor cells uniformly expressed HMGA2 protein in all cases, cytokeratin 7, S100 protein, and SOX10 displayed either diffuse positivity or highlighted the luminal and abluminal cell populations, respectively. Areas with morphological oncocytoid change and AR-immunopositivity of luminal cells were seen in 13/14 (93%) of tested biphasic cases. HMGA2 rearrangement was detected by RNA-sequencing in 30 cases. The most common alteration was an HMGA1::WIF1 fusion, but several novel or rare fusion partners were identified, including ARID2 , FHIT , MSRB3 and its antisense variant MSRB3-AS1 , IFNG-AS1 , and the long intergenic region LINC02389 . In addition, FISH revealed HGMA2 break-apart in the remaining 10 cases where targeted sequencing failed to detect any alteration or where RNA sequencing could not be performed. Notably, the loss of the 3'-untranslated region of HMGA2 emerges as the common denominator for the described rearrangements, possibly disrupting its negative regulation by small regulatory RNAs. Awareness of this lesion ensures appropriate diagnosis and clinical management, especially with regard to the possibility of malignant transformation described in this and previous studies.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"554-563"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12068546/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143539967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Primary Endometrial Gastric (Gastrointestinal)-type Mucinous Adenocarcinoma: A Detailed Clinicopathologic and Molecular Analysis of 27 Cases.","authors":"Harsimar Kaur, Lawrence Hsu Lin, David L Kolin, Andre Pinto, Carlos Parra-Herran, Mark Catherwood, Koen Van de Vijver, Natalia Buza, W Glenn McCluggage, Marisa R Nucci","doi":"10.1097/PAS.0000000000002382","DOIUrl":"10.1097/PAS.0000000000002382","url":null,"abstract":"<p><p>Endometrial gastric (gastrointestinal)-type mucinous adenocarcinoma (EmGA) is rare and was introduced as a new entity in the latest World Health Organization (WHO) classification of female genital tumors. Herein, we report a detailed clinicopathologic, immunohistochemical, and molecular study of 27 EmGA, the largest published series to date. The cohort consisted of 27 patients (median age 69 y; range 42 to 87 years). Histologically all cases showed gastric/gastrointestinal differentiation with foamy apical cytoplasm with distinct cell borders (n=21), goblet cells (n=9), signet ring cells (n=4), and Paneth cells (n=1). Using FIGO grading, 5 were grade 1, 14 grade 2, and 8 grade 3. Tumors were positive for MUC6 (10/21), CK7 (22/24), CK20 (16/24), CDX2 (24/26), and Claudin 18 (9/12). In all, 12/27 exhibited aberrant p53 expression and 3/26 showed MLH1 and PMS2 loss, including 2 with confirmed MLH1 gene promoter methylation. Next-generation sequencing showed pathogenic variants in TP53 (13/20), KRAS (7/20), PIK3CA (5/20), BRCA2 (4/20), SMAD4 (3/20), and POLE (1/20). Using TCGA classification (based on cases with available molecular results), 1/20 was POLE mutated, 2/20 were mismatch repair deficient (MMRd), 4/20 were no specific molecular profile (NSMP), and 13/20 were TP53 abnormal. FIGO stage (2009 staging system) ranged from IA to IVB. Outcome data (21 patients; follow-up of 2 to 77 mo) showed that 2 patients died of disease at 14 and 46 months after diagnosis, 1 patient died from other causes at 28 months, 8 were alive with disease, and 10 were alive with no evidence of disease. Like the cervical counterpart, primary EmGA has a distinctive morphologic appearance, harbors frequent TP53 mutations, and can be associated with adverse outcomes despite low-grade morphology and/or low-stage at presentation. They may be represented in all 4 TCGA molecular groups.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"564-577"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Response to Expanding Insights Into PRAME Expression in Merkel Cell Carcinoma.","authors":"Shyam S Raghavan","doi":"10.1097/PAS.0000000000002410","DOIUrl":"https://doi.org/10.1097/PAS.0000000000002410","url":null,"abstract":"","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":"49 6","pages":"637-638"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143962298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A High-grade PML::JAK1 Fusion Sarcoma.","authors":"Steven Christopher Smith, Julio A Diaz-Perez, Mark Cameron Mochel, Steven D Billings, Leopoldo Fernandez, Andrew S Poklepovic","doi":"10.1097/PAS.0000000000002326","DOIUrl":"10.1097/PAS.0000000000002326","url":null,"abstract":"","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"633-635"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142567796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MEIS1::NCOA1 Primitive Spindle Cell Sarcoma of the Kidney : Report of 7 Cases of a Distinctive Clinicopathologic Entity.","authors":"Pedram Argani, Sintawat Wangsiricharoen, Maria Tretiakova, Yajuan J Liu, Sara M Falzarano, Katrina Collins, Fadi Brimo, John M Gross, Ezra Baraban, Andres Matoso, Kristina Wakeman, Christopher Corless, Tanaya Neff, Benjamin F Smith, Ali Abdel Satir, Abbas Agaimy, Cristina R Antonescu, Gregory W Charville, Ankur R Sangoi","doi":"10.1097/PAS.0000000000002386","DOIUrl":"10.1097/PAS.0000000000002386","url":null,"abstract":"<p><p>Primitive sarcomas harboring the MEIS1::NCOA2 gene fusion were originally described in the kidney in 2018, and subsequently reported in other organs. These variably cellular neoplasms feature monomorphic primitive plump spindle cells forming nodules and whorls in addition to nondescript fascicular, solid, and storiform patterns. They lack skeletal muscle differentiation in contrast to the primarily intraosseous rhabdomyosarcomas that harbor the same gene fusion. We describe 7 new primary primitive renal sarcomas with MEIS1::NCOA1 gene fusions. Although their morphology overlaps with that described in MEIS1::NCOA2 renal sarcoma, 3 of the 7 cases contained adipose tissue. The majority had intimately admixed entrapped cystic epithelial elements and demonstrated patchy immunoreactivity for estrogen receptor and nuclear labeling for WT1 protein, leading to the differential diagnosis of malignant mixed epithelial stromal tumor (MEST) in 4 cases and metanephric stromal tumor in one. The neoplasms demonstrate a broad spectrum of clinicopathologic features ranging from a bland low-grade neoplasm that metastasized 9 years after diagnosis to a high-grade sarcoma with multiple recurrences, ultimately leading to patient death in under 1 year. In summary, MEIS1::NCOA1 primitive sarcomas overlap with the previously described MEIS1::NCOA2 primitive renal sarcomas and represent a distinctive renal neoplasm that can be mistaken for malignant MEST. Grade ranges from low to high but even low-grade neoplasms require long-term clinical follow-up.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"620-632"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143750685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cutaneous Hemangioma With Epithelioid Features Harboring TPM3/4::ALK Fusions : A Distinct Entity or a Molecular Variant of Epithelioid Hemangioma?","authors":"Carina A Dehner, George Jour, Maximilian Gassenmaier, Michael Michal, Nicolas de Saint Aubain, David J Papke, Brandon Umphress, Aofei Li, Mark M Tanner, Eduardo Calonje, Thomas Brenn, Christopher D M Fletcher, Thomas Mentzel, Klaus Busam, Konstantinos Linos","doi":"10.1097/PAS.0000000000002380","DOIUrl":"10.1097/PAS.0000000000002380","url":null,"abstract":"<p><p>Vascular neoplasms with epithelioid cytomorphology encompass a wide spectrum of benign and malignant lesions, including epithelioid hemangioma (EH), cutaneous epithelioid angiomatous nodule (CEAN), epithelioid hemangioendothelioma (EHE), and epithelioid angiosarcoma (EAS). Recently, the first case of a cutaneous hemangioma with epithelioid features harboring a TPM3::ALK fusion was reported. Herein, we report 4 additional cases, including 1 case with an alternate TPM4::ALK fusion, and expand on the clinicopathologic and molecular genetic features of these unusual vascular lesions. Including the previously reported case, 5 tumors occurred in 4 male and 1 female patients with a median age of 14 years (range: 2 to 38 y) and involved the shoulder region (2), the lower extremity (1), trunk (1), and head and neck (1). Clinical follow-up (3 patients; 60%) showed no evidence of disease at the last follow-up (median: 5 mo; range: 1 to 16 mo). Histologically, all tumors showed highly similar morphologic features, including an epidermal collarette, well-formed vascular channels composed of epithelioid endothelial cells with intracytoplasmic vacuoles, and admixed inflammatory cells. Immunohistochemically, all tumors were positive for vascular markers such as ERG and CD31, along with strong and diffuse cytoplasmic expression of ALK. RNA sequencing revealed recurrent TPM3 exon 8 :: ALK exon 20 (4) and TPM4 exon 7 :: ALK exon 20 fusions (1). We conclude that cutaneous hemangiomas with epithelioid features harboring TPM3/4::ALK fusions show consistent morphologic, immunophenotypic, and molecular genetic features. It remains to be determined whether this neoplasm represents a distinct entity or a molecular variant of epithelioid hemangioma.</p>","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"610-619"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Somatic Malignancies Arising in Ovarian Mature Cystic Teratomas: A Multi-Institutional Study of 40 Cases Highlighting Outcomes and Novel Malignancies.","authors":"Grace Neville, Kyle M Devins, Marisa R Nucci, Jaclyn C Watkins","doi":"10.1097/PAS.0000000000002384","DOIUrl":"10.1097/PAS.0000000000002384","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Somatic malignancy arising in ovarian mature cystic teratoma (MCT) is a relatively rare phenomenon with an estimated incidence ranging from 0.17% to 5.5%. Most previous studies have been limited by small sample sizes, hindering more precise estimates of incidence as well as providing limited prognostic information. We aimed to conduct a large-scale, multi-institutional study to better define incidence, discuss prognosis, and report occurrences of unusual malignancies arising in MCT. The pathology archives of the Massachusetts General Hospital and Brigham and Women's Hospital were searched for all cases of MCT arising between 2006 and 2021. The pathology reports were reviewed for the presence of somatic malignancy arising within MCT. Cases harboring somatic malignancy were re-reviewed by a gynecologic pathologist, with documentation of a number of histomorphologic variables, including surface involvement, lymphovascular invasion, and tumor size. Sociodemographic variables, adjuvant chemotherapy, disease recurrence/progression, and survival were extrapolated from the medical record. Among 2416 cases of MCT, 40 cases of somatic malignancy were identified. Tumors included squamous cell carcinoma (SCC, n=21), papillary thyroid carcinoma (PTC, n=7), sebaceous carcinoma (n=2), neuroendocrine carcinoma (n=2), and other rarer types. The mean age of patients was 49 years (range: 17.7 to 69.7 y). Follow-up data was available for 20 patients (range: 3 to 196 mo, mean: 80.5 mo). Eleven were ovarian confined without surface involvement; 9 were AJCC stage pT1C or higher at the time of diagnosis. Of ovarian confined tumors without surface involvement, only 1 recurred (a follicular variant of papillary thyroid carcinoma) with bone metastases found 72 months after initial diagnosis. Four additional cases, all of which were stage 1C or higher at initial diagnosis, recurred after initial resection, including 2 cases with SCC, 1 melanoma case, and 1 adenocarcinoma ex-Goblet cell carcinoid case. Tumors that recurred tended to have a large malignant component (range: 4 to 23 cm, mean: 16.8 cm). When cases received in consultation were excluded, the overall incidence of incidental somatic malignancy arising in MCT was 0.54% (13 of 2389 cases). Somatic malignancy in MCT is rare, and outcomes largely depend on the stage at initial diagnosis, and possibly, the size of the malignant portion of the tumor. Poor outcomes were noted across multiple histologies. Patients diagnosed with early-stage disease (stage IA) generally had a favorable prognosis, whereas those with advanced-stage disease (stage IC or higher) faced higher risks of recurrence and mortality. Nevertheless, some low-stage patients experienced recurrence, highlighting the need for long-term follow-up for all patients. More aggressive management strategies should be tailored on a case-by-case basis. The focality of residual MCT, in some cases, underscores the need for a thorough sampling of ovarian somatic ","PeriodicalId":7772,"journal":{"name":"American Journal of Surgical Pathology","volume":" ","pages":"527-538"},"PeriodicalIF":4.5,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}