Penile squamous cell carcinoma (pSCC) is a rare cancer associated with a relatively poor prognosis. The WHO classifies pSCC into HPV-associated and HPV-independent subtypes, with HPV-positive pSCCs showing slightly better outcomes. A key negative prognostic marker is TP53 mutation. The aim of this study was to evaluate the concordance of (1) p16 immunohistochemistry with HPV status determined by PCR, (2) p53 immunohistochemistry with TP53 mutational status obtained by NGS, and (3) prognostic impact of overexpression and null phenotype p53 immunohistochemistry profiles. Analyzing invasive pSCC from 209 patients, we assessed concordance between p16 immunohistochemistry and HPV status (n = 132) determined by quantitative PCR, obtaining Cohen's kappa Κ = 0.62 (p < 0.0001). For p53 immunohistochemistry versus TP53 status by NGS (n = 145), Cohen's kappa reached Κ = 0.693 (p < 0.0001). We found worse overall survival (Hazard ratio = 3.33, 95% CIs 1.92-5.56, p < 0.0001) in p53 mutated cases (n = 38, both overexpression and null phenotype) compared to wild type (n = 171), but without a significant difference between both mutated profiles. Both HPV status and p53 profile can be reliably assessed by immunohistochemistry with substantial agreement. Patients with a mutated p53 profile showed significantly worse survival, irrespective of the mutated profile variant.

Hemangioblastomas (HB) are rare CNS neoplasms. Their main differential diagnosis includes meningioma, glioma, and metastatic clear cell renal carcinoma. However, the diagnostic immunoprofile of HBs is only imprecisely defined. We analyzed a multicentric cohort of HBs using tissue microarrays and whole sections to determine immunoreactivities of a range of selected meningothelial, glial and other markers used in diagnostic pathology. The clinical and pathological features were correlated. The cohort included 112 tumors from 104 patients (46.1% males, 53.9% females) with a mean age 50.1 years. The tumors occurred in cerebellum (72%), spine (18.9%) and medulla oblongata (5.4%). No HB expressed SSTR2A, MUC4 or STAT6. Expression of glial markers S100, GFAP, Olig2, and SOX10 was observed in 93.3%, 80.6%, 5.1%, and 8.1% of cases, respectively. Inhibin-α was positive in 84.5% and carbonic anhydrase IX (CAIX) in 100% of the cases. Negative PAX8 immunostaining was observed using specific C-terminus antibody whereas N-terminus anti-PAX8 staining yielded 63.2% positivity. T-brachyury, SATB2, and GPNMB were observed in 3.8%, 2.1%, and 20.8%, respectively. No expression of SOX17, CDX2, Sall4, GATA3, or INSM1 was observed. Thus, HBs show a consistent PAX8-negative/CAIX-positive immunoprofile while they lack meningothelial markers and occasionally may express SOX10 and Olig2.

High-grade endometrial stromal sarcomas (HGESS) with BCOR-alteration include sarcomas with YWHAE::NUTM2A/B fusion, ZC3H7B::BCOR fusion, BCOR -ITD, BCOR alternative fusion, and BCORL1 fusion. Recently, 4 cases of uterine sarcomas with KDM2B fusion have been described, which were suggested to belong to the category of BCOR-altered tumors. These tumors are characterized by recurrent fusions of the KDM2B gene with fusion partners including EPC1 , EP400 , and CITED1 . Morphologically, some of them may have a nonspecific spindle-cell or round-cell appearance. In other tumors, however, peculiar morphologic features combining atypical round cells with at least focal sex cord-like features and myxoid stroma were found. In our study, we described 3 additional cases of uterine sarcomas with KDM2B fusion, with fusion partners including EPC1 , EPC2 , and CREBBP . Morphologically, these tumors showed either pure spindle-cell morphology, a combination of spindle and round cells, or a heterogeneous pattern with spindle cells, round cells, and prominent hyalinization, with only focal, vague sex cord-like features. Despite possible morphologic overlap with low-grade endometrial stromal sarcomas in some cases, these tumors seem to represent a variant of HGESS belonging to the category of BCOR-altered sarcomas and have a propensity for aggressive behavior, as 2 of our patients died of disease, and the third had pelvic recurrence before being lost to follow-up.

We report a case of a uterine mesenchymal tumor with myogenic differentiation and SRF::RELA fusion occurring in a 23-year-old woman manifesting as an endometrial polyp. The tumor consisted of bland spindle cells with a predominantly fascicular growth pattern and entrapment of the endometrial glands and vessels. The tumor was positive for smooth muscle markers and CD10. NGS RNA analysis revealed SRF::RELA fusion. NGS DNA analysis revealed no pathogenic variants or copy-number alterations. On follow-up 12 months after curettage, the patient showed no signs of the disease. To the best of our knowledge, only 3 cases of uterine tumors with SRF::RELA fusion arising in the gynecologic tract have been described previously, and all show benign behavior so far. Differential diagnosis includes both benign and potentially aggressive entities, such as leiomyoma, inflammatory myofibroblastic tumor, perivascular epithelioid cell tumor, uterine adenosarcoma, low-grade endometrial stromal sarcoma, and uterine sarcoma with KAT6B/A::KANSL1 fusion.

Penile carcinoma is a rare but psychosexually devastating malignancy associated with the worst prognosis among male-specific genitourinary malignancies (prostate, testicular, and penile cancer). In addition to loss of the organ itself, patients frequently suffer from chronic lymphedema following inguinal lymph node dissection. Despite advances in oncology, the prognosis of penile cancer has not substantially improved over the past half century, and the disease has long remained underrepresented in basic research, clinical trials, and patient advocacy initiatives. During the 2020s, however, the situation has begun to change, with an increasing number of large studies and the emergence of the first meta-analyses focused on penile carcinoma. Current morphological and molecular studies aim to identify features of aggressive disease that may guide treatment escalation or de-escalation and thereby improve patients’ quality of life. This review summarizes recent advances in the field, with particular emphasis on prognostic parameters accessible by routine histopathological examination. In many settings, simple pathological biomarkers may provide greater clinical utility than expensive molecular analyses. Special attention is devoted to the interplay between morphology, HPV status, immune microenvironment, and molecular alterations. The review discusses histological grading, morphological subtypes, HPV status and its correlation with morphology and mutational profiles, the prognostic significance of tumor-infiltrating lymphocytes and PD-L1 expression, and particularly tumor budding, which is strongly associated with aberrant p53 status and adverse prognosis. Future perspectives include refinement of penile carcinoma classification into: 1) HPV-associated, 2) HPV-independent, p53 wild-type, and 3) HPV independent, p53-altered tumors. Additional parameters with potential to improve prognostic stratification include tumor budding and the subjectively assessed peritumoral lymphocytic rim (brisk versus non-brisk), both of which appear suitable for routine reporting alongside conventional staging and grading. To sum up: Morphology really matters even in the molecular era.

Low-grade endometrial stromal sarcomas (LGESS) and endometrial stromal nodules represent a distinct entity with characteristic morphology, immunohistochemical profile, and molecular features. It has been suggested that the activation of the Wnt signaling pathway is a potential driver in some of these tumors. Approximately 70-75% of LGESS are characterized by non-random recurrent fusions mostly involving JAZF1 and PHF1 genes. Although the exact mechanism remains unclear, activation of the Wnt signaling pathway appears to be related to the functional deregulation of chromatin remodeling complexes caused by these fusion proteins. However, knowledge about other possible mechanisms and recurrent molecular alterations occurring at the DNA level in LGESS remains limited. We report three cases of LGESS in patients aged 39, 49, and 50, lacking recurrent fusions but harboring CTNNB1 mutations in exon 3 as the sole detectable molecular alteration. One case had morphological features of typical LGESS (in some areas with perivascular whorling, which was not a dominant feature), the second case showed features of the fibroblastic variant of LGESS, and the third case comprised a LGESS with a peculiar morphology with diffuse whorling morphologically identical to the recently described entity endometrial stromal tumor with GREB1::CTNNB1 fusion. RNA-Seq-based clustering analysis of the three cases and a set of 193 uterine tumors showed that the CTNNB1-mutated cases clustered near LGESS cases. This study adds to the growing body of evidence that CTNNB1 mutations represent a driver molecular event in a small subset of endometrial stromal tumors. Moreover, the results of our study suggest that tumors with CTNNB1 mutation and GREB1::CTNNB1 fusion may exhibit identical morphology and potentially represent the same category of tumor. Characterization and reporting of additional cases are needed to determine whether these are part of the spectrum of low-grade endometrial stromal tumors (either endometrial stromal nodule or LGESS) or represent a separate category of tumors characterized by CTNNB1 alteration as a driver event.

Small cell neuroendocrine carcinomas occur in both pulmonary (SCLC) and extrapulmonary sites (EP-SCNC). Although morphologically similar, they may differ biologically, but these differences are not well characterized. The aim of this study was to compare cohorts of SCLC (n = 215) and EP-SCNC(n = 184) with respect to molecular alterations, RNA and protein expression in tumor tissue. The median survival for SCLC was 6.3 months and 8.9 months for EP-SCNC patients (p < 0.0001). Genetic alterations of TP53, RB1, and KMT2D were the most common in both groups. The TP53 mutation was associated with worse survival in EP-SCNC (HR = 1.62; p = 0.043), while KMT2D was associated with worse survival in SCLC (HR = 1.62; p = 0.003). The tumor mutation burden (TMB) was higher in SCLC (p < 0.001). In RNA-Seq analyses, SCLC and EP-SCNC formed distinct RNA clusters. A total of 553 genes were differentially expressed. snoRNAs and tRNAs were predominantly upregulated in SCLC. GOAT analysis revealed upregulation in cell signaling and cellular plasticity in EP-SCNC, whereas SCLC showed enhanced transcriptional activity, including RNA processing and nuclear functions. Immunohistochemistry revealed higher expression of ASCL1 and NEUROD1 in SCLC than in EP-SCNC. YAP1 and POU2F3 expressions were higher in EP-SCNC. In multivariate analyses, EP-SCNC was associated with better survival, greater molecular heterogeneity, and distinct genetic, transcriptional, and immunohistochemical profiles. These findings demonstrate that, despite their morphological similarity, the two tumor groups are biologically distinct.

Uterine mesenchymal tumours represent a group of heterogeneous tumours, the classification of which is evolving, especially in the context of a broader use of molecular testing. Some entities can be diagnosed based on the combination of morphological and immunohistochemical features. In other entities, such as endometrial sarcomas with KAT6B/A::KANSL1 fusion, the correct diagnosis cannot currently be achieved without molecular testing. In this review, we focus on some of the new entities in which molecular testing plays an essential role for diagnosis, including tumours with KAT6B/A::KANSL1 fusion, tumours with MEIS1::NCOA2 fusion, and tumours with fusion involving the KDM2B gene. In addition, uterine tumours with whorling and GREB1:CTNNB1 fusion and endometrial stromal tumours with CTNNB1 mutation will be discussed. Other tumours with recurrent molecular alterations not specific to a single entity (such as tumours with PLAG1 fusion or RAD51B fusion) are also mentioned. In summary, molecular testing is a very important part of the classification of uterine mesenchymal tumours. The growing number of emerging entities helps to correctly classify tumours into clinically significant categories. However, these entities should be viewed with caution until their clinical significance is supported by robust data, and molecular findings should always be correlated with morphological features.

Adult granulosa cell tumors (AGCTs) of the ovary are characterized by their propensity for late recurrences and are primarily managed surgically due to the limited efficacy of systemic treatment. The FOXL2 p.C134W somatic mutation has been identified in similar to 95% of AGCT cases, and TERT promoter alterations have been linked to worse overall survival. This study highlights the potential prognostic significance of FOXO1 mutations, suggesting that they may be associated with poorer overall survival and shorter time to recurrence. A total of 183 primary AGCTs and 44 recurrences without corresponding primary tumors were analyzed. The primary AGCTs were categorized into 3 groups: 77 nonrecurrent tumors, 18 tumors that later recurred (including 9 cases with matched primary-recurrence pairs), and 88 tumors with unknown recurrence status. Targeted next- generation sequencing was conducted on 786 cancer-related genes to investigate their genetic profile. The study aimed to identify the molecular alterations associated with AGCT pathogenesis and recurrence rate, comparing primary versus recurrent tumors, and primary recurrent versus primary nonrecurrent cases. Our findings confirmed the high prevalence (99%) of the FOXL2 p.C134W mutation in AGCTs. Secondary truncating FOXL2 mutations were observed in 5% of cases. Two cases with typical AGCT morphology were FOXL2 wild-type, harboring mutations in KRAS or KMT2D instead, suggesting alternative genetic pathways. TERT promoter mutations were found in 43% of cases, more frequently in recurrences. Other recurrent mutations detected in the cohort included KMT2D (10%), FOXO1 (7%), CHEK2 (5%), TP53 (3.5%), PIK3CA (3.5%), and AKT1 (3%). Two recurrent, FOXL2-mutated cases also carried DICER1 mutations. One tumor exhibited MSI-high status and a tumor mutation burden of 19 mut/Mb. Our results indicate the need for further investigation into the role of FOXO1 as a potential prognostic marker in AGCTs. (c) 2024 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

CONTEXT.—:Non-smooth muscle uterine sarcomas are mostly represented by low-grade endometrial stromal sarcoma. However, several other rare, distinct types of uterine sarcoma are recognized, including high-grade endometrial stromal sarcoma, tumors with kinase fusions, uterine tumors resembling ovarian sex cord tumors, soft tissue-type sarcoma, and emerging entities such as KAT6A/B-rearranged tumors. The landscape of uterine sarcomas has changed, mostly because of the increasing knowledge concerning their molecular aberrations. OBJECTIVE.—:To offer a comprehensive review of the literature focusing on fusions occurring in tumors other than smooth muscle mesenchymal uterine tumors with respect to their type, frequency, and overlap between diagnostic categories and entities. DATA SOURCES.—:The data were mined from the PubMed/MEDLINE database covering the time period from January 1988 to June 2023. In total, 156 studies focusing on the problematics of fusions occurring in non-smooth muscle mesenchymal uterine tumors were selected, and thus became the basis for this review. CONCLUSIONS.—:One hundred ten fusions were identified in 703 tumors. The diagnostic significance of the molecular aberrations occurring in these tumors can be unclear in some cases. This can be related to the rare aberrations with a limited number of reported cases. Additionally, even well-known aberrations considered as specific for a certain distinct entity can occur in other lesions, the biological behavior and clinical significance of which can differ substantially.

Extrapulmonary small cell neuroendocrine carcinoma (EP-SCNC) is a rare malignancy with a poor prognosis. Despite its morphological similarity to lung small cell carcinomas, its oncogenesis remains uncertain. One hundred and seventy-one EP-SCNC were enrolled in a multicenter study, and all tissue samples underwent an immunohistochemical p53 analysis. One hundred twenty-five samples were molecularly analyzed using next-generation sequencing (NGS), comprising DNA and RNA analysis. p53 normal/wild type expression was detected in 68 cases (39.8%), whereas aberrant expression was detected in 103 cases (60.2%). Molecular TP53 alteration was detected in 92 out of 125 tumors (73.6%). The TP53 mutation was shown to be prognostic and associated with shorter overall survival ( p = 0.041). The multivariate analysis of p53 and TP53 mutational status found that it impacted overall survival relative to distinct sites of tumor locations ( p = 0.004 and p = 0.001, respectively). Age did not influenced survival in the multivariate analysis of p53 and TP53 ( p = 0.002; p < 0.001 resp.). Among tumors with paired immunohistochemical and molecular results, 108 exhibited concordance between the immunohistochemical and molecular analysis, whereas 17 were discordant. Accordingly, p53 aberrant expression was tightly associated with a TP53 mutation ( p < 0.001). In discordant cases, molecular analysis revealed no alteration in three tumors with p53 overexpression. In contrast, in 14 tumors with wild-type p53 expression, TP53 genetic alteration was detected. Possible causes of discordance are discussed in this manuscript. Furthermore, the incidence of aberrant p53 expression / TP53 molecular alteration was noticeably lower in EP-SCNC than in small-cell lung carcinomas. Therefore, in EP-SCNC, other driver mutations should be sought since personalized therapy can improve patient prognosis.

Extrapulmonary small cell neuroendocrine carcinoma (EP-SCNC) is a rare malignancy with a poor prognosis. Most patients with EP-SCNC have metastatic disease upon presentation, and their average overall survival (OS) is less than 12 months. Our study aimed to conduct a complex analysis of EP-SCNC. One hundred and eighty-one EP-SCNC tissue samples were subjected to a complex analysis. One hundred and fifty-five tumors were pure EP-SCNC, while 26 were combined tumors. Immunohistochemistry for ASCL1, NEUROD1, YAP1, POU2F3, Rb1, p53, cyclin D1, p16, PTEN, DLL3, PD-L1, CD56, synaptophysin, chromogranin A, and INSM1 was performed, and 128 samples were analyzed molecularly using next generation sequencing (NGS), comprising DNA and RNA analysis. Detailed results on immunohistochemical and molecular analyses were provided for each primary origin of EP-SCNC separately. Median survival for the whole cohort of patients was 8.94 months. Patient age (≥ 70 years), tumor mutational burden (TMB) < 15, and TP53 and BRCA2 mutations were negative prognostic factors. High expression of ASCL-1 was associated with shorter OS, whereas high expression of YAP1 was associated with longer OS. Patients with genitourinary tumors had significantly better OS than those with gastrointestinal tract EP-SCNC tumors. Rb1 expression loss was detected more often in genitourinary tract SCNCs. In contrast, p16 overexpression was found more often in genitourinary tract SCNCs. POU2F3 expression was detected more often in combined tumors, whereas NEUROD1 was detected more often in pure EP-SCNC. Regarding “druggable markers, ” DLL3 was expressed in 66% of tumors and PD-L1 in 17.4%.Detailed analyses of different prognostic and predictive markers are needed to better understand EP-SCNC biology and create more personalized therapy to improve patient prognosis. Radoslav Matej, Pavel Dundr, Klara Pavlickova, Marian Svajdler, Jan Hojny, Nikola Hajkova. Molecular and immunohistochemical classification of extrapulmonary small cell neuroendocrine carcinomas: A study of 181 cases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 4593.

In this study, we investigated human epidermal growth factor receptor 2 (HER2) aberrations, including gene amplification and mutation, and protein expression in 123 small cell lung carcinomas (SCLC) and 128 extrapulmonary small cell neuroendocrine carcinomas (EP-SCNC) samples. Among the EP-SCNC cohort, HER2 mutations were found in 5.5% of samples (7/128); urinary bladder (4 cases), and one case each in samples from the colon, anal canal, and uterine cervix. In SCLCs, HER2 mutations were rare, detected in only 0.8% (1/119) of cases. We also identified eight EP-SCNCs and five SCLC cases with HER2 gene variants of uncertain significance (VUS). HER2 gene amplification was detected in 2.3% (3/128) of EP-SCNCs, but no amplification was found in SCLCs. The differences in HER2 mRNA expression were not statistically significant among tumor groups in the EP-SCNCs and SCLCs cohorts. RNA-seq analysis revealed high HER2 mRNA expression in seven EP-SCNCs and four SCLCs. An immunohistochemistry (IHC) analysis of 10 available tumors with high mRNA expression revealed HER2 protein positivity in 8 cases. The prognostic value of HER2 overexpression in EP-SCNC patients was not established in our study. Furthermore, EP-SCNC patients with high HER2 mRNA expression were generally younger, with a mean age of 60 years. These findings highlight the potential of HER2 as a therapeutic target in EP-SCNC, warranting further investigation into its clinical implications.

The Rare Gynecologic Sarcoma study involved 23 institutions from 10 countries focusing on myxoid leiomyosarcoma and nonesmooth muscle uterine sarcomas. Here, we present the main results of the study, including the comparison between the original and final diagnosis, the frequency and type of molecular aberrations, and the clinicopathologic outcomes. A total of 379 cases were included, with available results for next-generation sequencing (NGS) RNA in 338 of 379 cases and NGS DNA in 335 of 379 cases. According to the original diagnoses, the study included 204 cases of low-grade endometrial stromal sarcoma (LG-ESS), 75 cases of high-grade endometrial stromal sarcoma (HG-ESS), 74 cases of undifferentiated uterine sarcoma (UUS), 17 cases of myxoid leiomyosarcoma, and 9 cases of unclassifiable sarcoma. The results of our second reading showed that 29% (110/379) of all the tumors had been originally misdiagnosed. After the reclassification, the final diagnoses were 147 cases of LG-ESS, 69 cases of HG-ESS, 58 cases of UUS, 3 cases of LGESS with high-grade transformation, 7 cases of perivascular epithelioid cell tumor, 9 cases of uterine tumor resembling ovarian sex cord tumor, 8 cases of tumors with a KAT6B/A::KANSL1 fusion, 2 cases of tumors with an NTRK fusion, 29 cases of undifferentiated carcinoma, and 47 tumors with smooth muscle differentiation. The molecular testing showed that LG-ESS harbor a recurrent fusion in 75.9% and HG-ESS in 43.7% of cases. The results of our study emphasize the diagnostic, prognostic, and predictive significance of molecular testing in mesenchymal uterine tumors. (c) 2025 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Assessing the biological behavior of uterine inflammatory myofibroblastic tumors (IMTs) remains challenging. This study evaluated previously proposed risk schemes and features in 9 IMTs (6 indolent, 3 aggressive) by integrating clinicopathological features, immunohistochemistry, and next-generation sequencing (NGS). High-risk features (necrosis, infiltrative growth, nuclear atypia) were present in both groups, with LVSI in 1/3 of aggressive IMTs. Aberrant p16 expression and CDKN2A/2B deletions were noted in 2/3 aggressive cases. All cases harbored ALK fusions, wild-type p53, and lacked pathogenic gene mutations. Aggressive cases harbored arm-level and segmental copy number gains/losses at chr 1, 2, X, and had significantly reduced AR expression. The clinicopathological risk stratification score (CRSS) predicted the biological behavior correctly in cases with complete clinicopathological data (size, mitoses, age, infiltrative growth). Two morcellated cases (one indolent and one aggressive) would have been predicted as low risk based solely on the absence of pathogenic mutations. Hereby, the reliability of the proposed CRSS was confirmed. Aberrant p16 expression predicted malignant behavior in 2/3 aggressive cases. Absence of pathogenic mutations or presence of large scale CNVs does not seem to be a predictor of clinical behavior. Additional studies and NGS analyses of more cases may improve risk stratification for patients with incomplete clinicopathological information and may reveal additional risk stratifiers (such as the suggested large-scale CNVs or AR downregulation) for IMTs.

Extrapulmonary small cell neuroendocrine carcinoma (EP-SCNC) is a rare malignancy with a poor prognosis. Most patients with EP-SCNC have metastatic disease upon presentation, and their average overall survival (OS) is less than 12 months. Our study aimed to conduct a complex analysis of EP-SCNC. One hundred eighty-one EP-SCNC tissue samples were subjected to a complex analysis. One hundred fifty-five tumors were pure EP-SCNC, whereas 26 were combined tumors. Immunohistochemistry for ASCL1, NEUROD1, YAP1, POU2F3, Rb1, p53, cyclin D1, p16, PTEN, DLL3, PD-L1, CD56, synaptophysin, chromogranin A, and INSM1 was performed, and 128 samples were analyzed molecularly using next-generation sequencing, comprising DNA and RNA analyses. Detailed results on immunohistochemical and molecular analyses were provided for each primary origin of EP-SCNC separately. Median survival for the whole cohort of patients was 8.94 months. Patient age (>= 70 years), tumor mutational burden <15, and TP53 and BRCA2 mutations were negative prognostic factors. High expression of ASCL-1 was associated with shorter OS, whereas high expression of YAP1 was associated with longer OS. Patients with genitourinary tumors had significantly better OS than those with gastrointestinal tract EP-SCNC tumors. Rb1 expression loss was detected more often in genitourinary tract SCNCs. In contrast, p16 overexpression was found more often in genitourinary tract SCNCs. POU2F3 expression was detected more often in combined tumors, whereas NEUROD1 was detected more often in pure EP-SCNC. Regarding "druggable markers," DLL3 was expressed in 66% of tumors and PD-L1 in 17.4%. Detailed analyses of different prognostic and predictive markers are needed to better understand EP-SCNC biology and create more personalized therapy to improve patient prognosis. (c) 2025 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Low-grade endometrial stromal sarcomas (LG-ESS), high-grade ESS (HG-ESS), undifferentiated uterine sarcomas (UUS), and uterine tumors resembling ovarian sex cord tumors are distinct non-smooth muscle cell neoplasms with varying clinical outcomes, often exhibiting overlapping characteristics. Diagnosis can be supported by identifying characteristic recurrent translocations, which may be absent in some cases, complicating the distinction of equivocal cases. Additionally, cases with overlapping features of low-grade and high-grade characteristics are recognized. To address these challenges, we analyzed RNA-seq profiles of 262 cases. Our results revealed that LG-ESS, with and without recurrent fusions, clustered into 2 partially overlapping expression profiles associated with distinct overall and relapse-free survival outcomes, with the cluster containing a majority of fusion-negative tumors demonstrating better prognoses. uterine tumors resembling ovarian sex cord tumors expression profiles closely resembled those of both LG-ESS subgroups, with NCOA3 fusion-positive cases clustering in groups with better survival outcomes. Furthermore, a distinct cluster for HG-ESS with BCOR and YWHAE fusions was identified, differentiating these tumors from HG-ESS without fusions. ONECUT3 emerged as a potential specific marker for this HG-ESS-fusion entity. A significant expression overlap was observed between monomorphic HG-ESS without fusions and pleomorphic UUS. These samples separated further into 2 mixed clusters distinguished by differences in immune activity, which significantly influenced overall survival and relapse-free survival outcomes. Unsupervised clustering of UUS revealed subgroups resembling either HG-ESS or muscle-cell-differentiated tumors, suggesting that UUS may include poorly differentiated distinct entities, such as leiomyosarcoma, and that the distinction from HG-ESS may, in some cases, be arbitrary. Our transcriptome analysis highlights several entities with distinct survival characteristics, providing a foundation for further characterization of these rare, often difficult-to-classify, tumors.

Penile squamous cell carcinoma (pSCC) is a rare genitourinary tumor associated with notable psychosexual distress and poor prognosis. Traditional prognostic factors for pSCC include TNM stage and histological grade, with lymph node metastases being a critical indicator of poor prognosis. This study aimed to evaluate the prognostic impact of the following immunohistochemistry markers routinely used in histopathology practice: GATA3, IMP3, HIF-1-α, CK7, CA-IX, HER2, and TTF-1. A retrospective cohort of 145 patients with pSCC was analyzed using tissue microarray and immunohistochemical techniques. Overall survival (OS) was correlated statistically with detected marker expression. Key findings include that low GATA3 expression is associated with significantly worse OS in univariate Cox regression truncated at 3 years of follow-up. Low GATA3 retained prognostic impact when adjusted for major clinicopathological variables: Age, pT and pN stage, grade, lymphatic, venous, and perineural invasion, lymphocytic infiltrate, and expression of p16, p53, and PD-L1. Low GATA3 expression was associated with shorter cancer-specific survival (CSS) at 10 years follow-up. IMP3, CK7, and CA-IX showed statistically insignificant trends towards poorer prognosis. CK7 and CA-IX were more frequently expressed in high grade pSCC and in p16/HPV-positive tumors. IMP3 and CA-IX were associated with regional lymph node metastases. All cases were negative in TTF-1 and HER2. This study suggests GATA3 as a potential prognostic marker in pSCC.

Several prognostic markers, including tumor-infiltrating lymphocytes, which have been recently identified in penile squamous cell carcinoma (pSCC), have focused mostly on T cells. The prognostic role of B cells and tertiary lymphoid structures (TLSs) has not yet been sufficiently described. We examined whole tissue sections histopathologically for TLSs and immunohistochemically for CD20 and CD138. The B-cell immunoscore (B-IS) divided the cohort into five categories based on the expression of these two B-cell/plasma cell markers (CD20 and CD138, respectively). Patients with fewer TLSs had worse overall survival (OS) [hazard ratio (HR) = 2.17; 95% CI: 0.94-5; p = 0.069]. A significant association was identified between a high TLS diameter and the presence of a lymphocytic infiltrate [odds ratio (OR) = 2.2442; 95% CI: 1.1022-4.55; p = 0.0208]. Patients with low B-IS (HR = 1.89, 95% CI: 1.18-3.03, p = 0.008), a low number of CD20+ cells in the tumor center (HR = 1.67, 95% CI: 1.04-2.7, p = 0.035), and a low number of CD20+ cells at the tumor invasion front (HR = 1.69, 95% CI: 1.06-2.78; p = 0.028) had significantly worse OS. High B-ISs were strongly associated with a mutated p53 profile detected by immunohistochemistry (OR = 4.76, 95% CI: 1.32-25, p = 0.011), low T-cell immunoscores (OR = 0.49; 95% CI: 0.23-1.03; p = 0.051), and brisk lymphocytic infiltration (OR = 2.0417, 95% CI: 1.01-4.76; p = 0.037). High CD20+ cell counts at the invasion front were associated with histological grade 3 disease (OR = 2.44, 95% CI 1.15-5.26, p = 0.015). An association was also observed between low B-IS and mutations in KMT2D (OR 0.31, 95% CI: 0.07-1.21, p = 0.057) and EGFR (OR = ∞, 95% CI: 0.86-∞, p = 0.053). In conclusion, high numbers of tumor-infiltrating B cells within TLSs represent a favorable prognostic marker in pSCC. These findings emphasize the need to identify novel microscopic prognostic markers during pathological assessment to guide early and appropriate therapeutic strategies.