International Journal of Gynecological Pathology最新文献

At present, the prevailing concept is that high-grade serous carcinoma (HGSC) arises from the fallopian tubes (FTs). We report an HGSC case occurring in a serous ovarian cyst against the background of a serous tubal intraepithelial carcinoma (STIC)-like lesion. We also provide a literature review that contains references to clinical cases of the occurrence of STIC-like lesions in the ovary and phylogenetic studies that do not always reveal obvious bonds between early dysplastic serous lesions and HGSC. The article discusses cases of association between HGSCs of serous borderline tumors (SBTs) and low-grade serous carcinomas (LGSCs) in the context of their possible histogenetic relationship. We propose a concept in which high-grade serous carcinogenesis, represented by the p53-signature-STIC-HGSC continuity, occurs in the serous epithelium of both the FT and other locations.

Summary: Netrin-1, an epithelial-secreted protein, plays a key role in placental formation through the promotion of cytotrophoblast proliferation and placental vascular development. These effects are mediated through several receptors, including the deleted in colorectal cancer (DCC) receptor. Placenta accreta spectrum (PAS) is an exaggerated trophoblastic invasion into the uterine myometrium. The exact etiology is unknown, but it is believed that increased trophoblastic invasion, defect decidualization, and/or abnormal angiogenesis might play a role. Our study aimed to investigate the suggested role of macrophage-induced netrin-1/DCC/vascular endothelial growth factor (VEGF) signaling in PAS pathogenesis. A total of 29 women with PAS (as cases) and 29 women with normal pregnancies (as controls) were enrolled in the study. At delivery, placental tissues of both groups were collected and processed for the evaluation of placental netrin-1 level by enzyme-linked immunoassay technique and immunohistochemical analysis of tissue DCC receptor. Placental tissue netrin-1 level of PAS cases showed a statistically significantly higher value than those in the normal group. Significant overexpression of DCC receptors, VEGF, and enhanced macrophage recruitment was noted in PAS cases in comparison to the normal placenta. Macrophage-induced netrin-1/DCC/VEGF signaling might be involved in PAS pathogenesis through the enhancement of trophoblastic angiogenesis.

The administration of immune checkpoint inhibitors (ICIs) is increasing in endometrial cancer, especially in the mismatch repair (MMR)-deficient group. To prevent unnecessary immune-related adverse events, ICIs need to be administered to more appropriate patients. The tumor immune microenvironment has been reported to be a predictive marker of the efficacy of ICI therapies. This study evaluated CD8, FoxP3, CD68, PD-L1, and β-catenin expression in endometrial endometrioid carcinoma, grade 1 (G1) with DNA mismatch repair protein loss (MMR loss), and their association with clinicopathological features. We retrospectively analyzed tumor samples from 107 patients with endometrial endometrioid carcinoma, G1 (MMR-deficient group: n=67; MMR-proficient group: n=40). Overall, 47 cases of MLH1/PMS2 loss and 20 cases of MSH2/MSH6 loss were observed. The patients with low intraepithelial CD8 expression significantly more frequently exhibited deep myometrial invasion, and the elderly group (≥60 y) significantly more frequently showed low stromal CD8 expression. In addition, FoxP3-positive cell count and FoxP3/CD8+ ratio were significantly correlated with the International Federation of Obstetrics and Gynecology 2023 stage and lymph node metastasis. In the Kaplan-Meier analysis, the patients with low intraepithelial or stromal CD8 expression had shorter progression-free survival (PFS) than those with high intraepithelial or stromal CD8 expression, albeit not significantly. We clarified that the tumor immune microenvironment had an impact on clinicopathological features within the group with MMR loss, which is the main target for ICIs, limited to endometrioid carcinoma, G1. Further studies are needed, including on patients administered ICIs.

Low-grade serous carcinoma (LGSC) is an uncommon histotype of ovarian carcinoma, accounting for ~3% of cases. There is evidence that survival of peritoneal LGSC (pLGSC) is longer than that of ovarian LGSC (oLGSC). Key molecular alterations of LGSC have been established, including loss of CDKN2A and PR expression, MAPK pathway alterations, and loss of USP9X expression. We hypothesized that LGSC could be subclassified into clinically applicable molecular subtypes by a few surrogate tests similar to endometrioid carcinomas using a hierarchical decision tree based on the strength of the prognostic associations of the individual alterations. Our study included 71 LGSCs. Immunohistochemistry for CDKN2A, ER, PR, NF1, and USP9X and sequencing for KRAS , NRAS , and BRAF were performed. Our data showed the co-occurrence of key molecular alterations, and despite suggestive trends, hierarchical molecular subtyping did not provide significantly different stratification of patients according to survival in this cohort. We confirmed that patients diagnosed with pLGSC have a longer survival than high-stage oLGSC, with the intriguing observation that normal CDKN2A and PR status were associated with excellent survival in pLGSC. Therefore, CDKN2A and PR status might aid in the classification of indeterminate implants, where abnormal findings favor pLGSC over noninvasive implants. Molecular subtypes should be further evaluated in larger cohorts for their prognostic and potentially predictive value.

SOX17 has recently emerged as a novel immunohistochemical marker for cancers of endometrial and ovarian origin with improved specificity compared with the widely used Mullerian marker PAX8. However, evaluation of SOX17 in benign and malignant peritoneal mesothelial proliferations remains limited, and these may mimic gynecologic carcinomas, particularly on small biopsies. We evaluated SOX17 and PAX8 expression in 20 benign mesothelial lesions (5 adenomatoid tumors, 5 well-differentiated papillary mesothelial tumors, and 10 peritoneal inclusion cysts) and 16 epithelioid peritoneal mesotheliomas. The 17 female and 3 male patients with benign mesothelial lesions ranged from 20 to 80 yr (median: 56.5 yr), while the 9 females and 7 males with mesothelioma ranged from 47 to 85 yr (median: 57.5 yr). SOX17 was positive in 5 (25%) benign lesions (2 adenomatoid tumors, 3 peritoneal inclusion cysts) and 2 (13%) mesotheliomas, while PAX8 stained 8 (40%) benign lesions (1 adenomatoid tumor, 1 well-differentiated papillary mesothelial tumor, 6 peritoneal inclusion cysts), and 2 (13%) mesotheliomas. Results for the 2 stains showed incomplete concordance, with agreement in 15 (75%) benign proliferations and 14 (88%) mesotheliomas. Our findings suggest that SOX17 positivity alone is insufficient to confirm a diagnosis of gynecologic carcinoma over a mesothelial proliferation and pathologists should exercise caution when these entities are diagnostic considerations.

Tumor human papillomavirus (HPV) status is an important prognostic factor in vulvar cancer as indicated in the latest WHO classification of female genital tract tumors. Immunohistochemical detection of p16 is well established as a surrogate biomarker for tumor HPV association, including squamous cell carcinomas of the vulva. HPV-independent vulvar carcinomas are heterogeneous with 2 subcategories according to the TP53 mutation status. Therefore, the simultaneous use of p53 and p16 immunohistochemistry is recommended for accurate subclassification of vulvar squamous cell carcinomas. However, the role of molecular analytical tools, in particular RNA ISH and TP53 sequencing, is not so clear. This study aimed to investigate the performance of p53 and p16 immunohistochemistry for the diagnosis of vulvar carcinomas in comparison to TP53 mutation analysis and HPV RNA ISH. We analyzed 48 vulvar carcinomas in a tissue microarray format. Sensitivity and specificity for both methods, p16 (100% and 96%) and p53 (95% and 90%) immunohistochemistry for detection of HPV association as well as for TP53 mutations was high. Combining p16 and p53 immunohistochemistry we correctly classified all carcinomas in our series according to current WHO criteria. The sensitivity of HPV RNA ISH for the detection of HPV association was lower compared to p16 immunohistochemistry. Rare HPV-associated cases with TP53 mutation and HPV-independent tumors with p16 overexpression are discussed. In summary, the combined use of p16 and p53 immunohistochemistry for subclassification of vulvar carcinomas is justified in daily practice. Molecular tests should be restricted to rare cases with ambiguous clinicopathologic or immunohistochemical features.

An adenomatoid tumor (AT) is a benign lesion, which is commonly located in the genital tract of both sexes. We present a case of a 66-yr-old woman with the unusual characteristics of an AT mimicking peritoneal carcinomatosis. The tumor was detected incidentally by ultrasound examination, and an ensuing imaging study raised suspicion of ovarian cancer with peritoneal carcinomatosis. From the pathologic diagnosis of frozen specimens, clear cell carcinoma was noted and the patient subsequently underwent cytoreductive surgery. An 8.5-cm-sized mass was observed on the uterine serosa, extending into the myometrium. In addition, multi-cystic nodular lesions were identified in the omentum, appendiceal and small bowel serosa, and the peritoneum. After histologic and extensive immunohistochemical examinations, the final diagnosis was AT. Recognition of the diverse presentations of AT is crucial for accurate diagnosis and appropriate treatment, as these tumors can involve multiple sites and mimic peritoneal carcinomatosis, potentially leading to a misdiagnosis of malignancy.

HER2 amplification in cervical cancer has been associated with worse clinical prognosis and a potential favorable response to HER2 inhibitors. Immunohistochemistry for the HER2 receptor is a universally accepted surrogate test for HER2 amplification, but no standardized scoring system currently exists for cervical carcinomas. In this study, we investigated HER2 overexpression in cervical squamous cell carcinoma and correlated it with HER2 amplification using fluorescence in situ hybridization (FISH) and molecular methods. Seventy-two cases of human papillomavirus-associated cervical cancer were retrospectively reviewed, and at least 2 representative tumor sections were stained for HER2. HER2 scoring was performed using the 2018 American Society of Clinical Oncology/College of American Pathologist breast cancer criteria, and cases with equivocal (2+) to positive (3+) expression were analyzed for HER2 amplification using FISH and next-generation sequencing. The average patient age was 50 yrs (range: 27-85 yr), with most patients being African American (73.6%) and diagnosed at FIGO stage I (65.3%). Nineteen (26.4%) had equivocal HER2 expression and 4 (5.5%) showed positive expression. Three of the 4 cases with positive expression had enough tumors for FISH, and all 3 were amplified. Three cases with equivocal expression showed HER2 polysomy on FISH, and none showed HER2 amplification. Late clinical stage, high tumor grade, and regional lymph node metastasis were significantly correlated with HER2 overexpression and HER2 amplification. Next-generation sequencing of the 3 HER2-amplified tumors showed amplification of various genes, including CD274, JAK2, BIRC3, and ERBB2, and a PIK3CA missense mutation. In summary, HER2 immunohistochemistry is a reliable predictive marker of HER2 amplification in cervical cancer.

High-grade endometrioid carcinomas occasionally demonstrate solid basaloid morphology with geographic necrosis (SB-GN). This pattern is among the defining features of pilomatrix-like high-grade endometrioid carcinoma (PiMHEC), a recently proposed tumor type which is additionally characterized by the presence of shadow cells, abnormal beta-catenin/CTNNB1 mutations, strong CDX2 expression, and poor outcomes. Clinicopathologic overlap between PiMHEC and other high-grade endometrial cancers with SB-GN has not been established. We screened 300 endometrial carcinomas on tissue microarray for SB-GN histology and performed a detailed whole-section morphologic review, immunohistochemical analysis, and next-generation sequencing on all cases bearing this pattern. Four (1.3%) demonstrated SB-GN. All 3 with clinical follow-up had extremely aggressive behavior despite being MMR-deficient; in contrast, only 27% of other MMR-deficient high-grade carcinomas recurred. One SB-GN case met most of the previously outlined diagnostic criteria for PiMHEC including abnormal beta-catenin/CTNNB1 (p.S37P variant) and strong CDX2 expression; notably, however, shadow cells were absent. This case also demonstrated a KRAS p.A59T pathogenic variant. The other 3 cases also lacked shadow cells; the 2 with sequencing data bore no CTNNB1 abnormalities but showed likely oncogenic variants involving the pilomatrixoma-associated gene FGFR2. All 3 cases with molecular results also bore somatic Notch pathway (NOTCH1/NOTCH2/NOTCH3) variants. The single case treated with immunotherapy showed complete and sustained response with regression of bone metastases despite abnormal beta-catenin/CTNNB1, which has been associated with immunotherapeutic resistance. These data suggest that the SB-GN pattern may connote a poor prognosis even in the absence of overt pilomatrix-like differentiation, and that novel molecular events may have implications for the treatment of these tumors.

Nuclear laminar or inner nuclear membrane proteins, including lamin A, B1, and B2 and emerin, are involved in maintaining nuclear morphology. However, their expression patterns vary among tumors and remain incompletely understood. Endometrioid carcinoma (EC) exhibits mild nuclear atypia, although the underlying reasons have not been thoroughly explored. In this study, we quantitatively analyzed emerin and lamin A, B1, and B2 expression levels in normal endometrium (NE), precancerous lesions, and EC using computer-assisted image analysis to assess the proteins' roles in nuclear morphologic change during tumorigenesis. From NE to EC, nuclear size remained unchanged, and lamin A and emerin were consistently expressed at low levels, whereas lamin B1 and B2 expression gradually decreased. Given the association between lamin A and emerin as well as their roles in nuclear morphology, these results indicate that their consistent low expression may underlie the preservation of nuclear size and shape in EC relative to NE. Conversely, lamin B1 and B2 are implicated in tumor progression rather than nuclear morphology maintenance. As lamin A and emerin are expressed in many organs and tumors, the consistently low expression of these proteins from NE to EC highlights a notable feature of the endometrium and endometrial carcinogenesis.