Rapid postradiation malignant transformation of a pilocytic astrocytoma in an adult with neurofibromatosis type 1: illustrative case.

BACKGROUND: Juvenile pilocytic astrocytoma (JPA) is the most common primary brain tumor of childhood and is rarely seen in adults. Neurofibromatosis type 1 (NF1), a common tumor predisposition syndrome, demonstrates a strong association with low-grade gliomas, most notably pilocytic astrocytoma, which are relatively indolent. Unlike its juvenile counterpart, reports of adult pilocytic astrocytoma (APA) vary widely in terms of disease progression from benign to much more malignant courses. Moreover, current studies discussing APA report different treatment approaches and outcomes (e.g., malignant transformation of JPA and APA with or without radiation), as little is known regarding the management of recurrent tumors and how adjuvant therapies may alter disease progression. OBSERVATIONS: The authors report the unique case of an adult male with NF1 and APA who underwent rapid malignant conversion after intensity-modulated radiation therapy. LESSONS: The authors demonstrate that caution should be taken in utilizing radiotherapy instead of resection in cases of APA and NF1, with close monitoring for posttreatment recurrence. https://thejns.org/doi/10.3171/CASE24241.

Malignant Recurrence of Benign Odontogenic Tumors (A Single Center Cross-Sectional Study).

BACKGROUND: Despite their rarity, malignant odontogenic tumors (MOT) represent an important group of oral lesions characterized by their variable clinical presentations and sometimes unexpected biological behavior. OBJECTIVES: The purpose of this retrospective cross-sectional study was to evaluate the number, types, and frequency of MOT and to investigate the relative rate of malignant transformation in recurrent odontogenic tumors (OT). METHODOLOGY: The records of patients diagnosed with OT in the hospital of the Faculty of Dentistry, Cairo University, were reviewed over 10 years (2013-2022). The OT were investigated for frequency, age, gender, site, and recurrence. The data were recorded and then analyzed using SPSS software version 25. RESULTS: Among 5543 oral excisions, 357 cases of them were OT, including 336 benign (94.1%) and 21 malignant neoplasms (5.9%). Among the odontogenic malignancies, 18 lesions (85.7%) appeared de novo, and 3 lesions (14.3%) developed as recurrent of previously classified benign tumors. A high incidence was observed in the middle and old age groups (90.4%) with a median age being 42. Slight male predilection (1.3:1) was noticed. The mandible was the highly affected site but all recurrent cases were diagnosed in the maxilla as ghost cell odontogenic carcinoma (n = 2, 66.6%) and primary intraosseous carcinoma (n = 1, 33.3%). CONCLUSION: Retrospective analysis of the relative frequency of MOT and the documentation of the unusual recurrence of benign OT as a malignancy enhances our understanding of OT behavior and the need for appropriate therapy and clinical follow-up.

Frozen in Time: Intraoperative Diagnosis and Management of Malignant Transformation in Mature Cystic Teratoma.

Malignant transformation (MCT) of ovary is rare complications affecting elderly, squamous cell carcinoma being the most common. The prognosis worsens with extraovarian spread. We present two cases of MCT-derived SCC. Patients exhibited abdominal lump, pain, bowel symptoms, sometimes with weight loss; imaging revealed MCT. Age (51-60), postmenopausal status, large size (>20 cm), bilaterality, and complex ovarian lesions raised suspicion of malignancy. Elevated tumor markers (e.g., cancer antigen-125 and lactate dehydrogenase) were noted in one case. Intraoperative frozen section confirmed malignancy, guiding staging laparotomy. One case was advanced stage on histopathology. Intraoperative frozen section aids optimal staging.

Optimizing Surgical Outcomes for Intracranial Epidermoid Tumors: A Retrospective Analysis of Clinical Predictors, Surgical Decisions, and Patient Clustering.

INTRODUCTION: Intracranial epidermoid tumors (ETs) are rare, benign lesions that present significant challenges in neurosurgical management due to their propensity to encase vital neurovascular structures. OBJECTIVE: To evaluate the impact of clinical, demographic, and tumor-specific factors on surgical decisions (gross total resection [GTR] vs. subtotal resection [STR]) and outcomes and identify patient clusters with distinct profiles and outcomes post-resection. METHODS: We retrospectively analyzed 72 epidermoid brain tumor patients treated from 1998 to 2022, employing multivariable logistic regression for GTR vs. STR predictors and Kaplan-Meier curves for progression-free survival (PFS). K-prototype clustering classified patients based on clinical data. RESULTS: The mean age of our cohort was 39.8±20.1 years. 13.9% of patients had a recurrence, with a median PFS of 108 months (IQR 57-206). Seizures significantly predicted GTR (p<0.05), whereas adherence to critical structures reduced GTR likelihood (p<0.05). Initial surgeries more often achieved GTR, correlating with longer PFS (p<0.0001) and reduced recurrence (p<0.01). History of previous ET surgery was predictive of increased recurrent tumor size (p<0.05) and reduced overall PFS (p<0.05). Clustering analysis revealed three clusters with significant differences in recurrence rates (p<0.0001), long term neurological deficits (p<0.05), PFS greater than 10 years (p<0.0001), and significant differences in median PFS between clusters 1 and 3 (p<0.0001) as well as 2 and three (p<0.01). CONCLUSION: This study emphasizes the importance of tailored surgical strategies in managing intracranial ETs, advocating for GTR to optimize long-term outcomes where possible. Future prospective studies are essential to further refine treatment approaches, enhancing survival for ET patients.

Low expression of Lnc-ENST00000535078 inhibits the migration, invasion, and enhances apoptosis of CTPE-induced malignantly transformed BEAS-2B cells.

Long non-coding RNA (LncRNA) plays an important role in malignant transformation of cells. This study aimed to explore the role of Lnc-ENST00000535078 in the malignant transformation of immortalized human bronchial epithelial cells (BEAS-2B) induced by coal tar pitch extract (CTPE). The malignant transformation model of BEAS-2B cells exposed to CTPE. Cell proliferation was examined by Cell counting kit-8 (CCK-8) assay. Colony formation assay was used to assess the colony of cells. Cell migration and invasion were detected by Transwell analysis. Cell cycle progression and apoptotic status were assessed by flow cytometry. Differentially expressed genes were screened by RNA sequencing. The results showed that Lnc-ENST00000535078 expression was highest in malignantly transformed BEAS-2B cells passaged to the 30th generation. Knockdown of Lnc-ENST00000535078 inhibited the migration, invasion and anti-apoptotic abilities of malignantly transformed BEAS-2B cells. Transcriptome analysis found 608 differential genes. CCND1 and FOS genes were screened out because of their levels were positive correlation with the expression of Lnc-ENST00000535078, which were consistent with the RNA sequencing results. In conclusion, Low expression of Lnc-ENST00000535078 inhibits the migration and invasion of malignant transformed BEAS-2B cells and promotes apoptosis in these cells. Lnc-ENST00000556926 might affect the malignant transformation of cells through the regulation of CCND1 and FOS. This study may provide a potential target for intervention in CTPE-induced lung cancer.

Dental pulp stem cells promote malignant transformation of oral epithelial cells through mitochondrial transfer.

Oral epithelial dysplasia includes a range of clinical oral mucosal diseases with potentially malignant traits. Dental pulp stem cells (DPSCs) are potential candidates for cell-based therapies targeting various diseases. However, the effect of DPSCs on the progression of oral mucosal precancerous lesions remains unclear. Animal experiments were conducted to assess the effect of human DPSCs (hDPSCs). We measured the proliferation, motility and mitochondrial respiratory function of the human dysplastic oral keratinocyte (DOK) cells cocultured with hDPSCs. Mitochondrial transfer experiments were performed to determine the role mitochondria from hDPSCs in the malignant transformation of DOK cells. hDPSCs injection accelerated carcinogenesis in 4NQO-induced oral epithelial dysplasia in mice. Coculture with hDPSCs increased the proliferation, migration, invasion and mitochondrial respiratory function of DOK cells. Mitochondria from hDPSCs could be transferred to DOK cells, and activated mTOR signaling pathway in DOK cells. Our study demonstrates that hDPSCs activate the mTOR signaling pathway through mitochondrial transfer, promoting the malignant transformation of oral precancerous epithelial lesions.

Novel role of CD34+ stromal cells/telocytes in oral submucous fibrosis development and its malignant transformation.

BACKGROUND: Telocytes are interstitial cells widely distributed in the extracellular matrix of numerous tissues distinguished by their long, thin, and moniliform projections. Telocytes have a role in the stimulation of angiogenesis and contribute to the development and progression of fibrosis. AIM: The current study aimed to assess and compare the telocyte distribution in normal mucosa, oral submucous fibrosis (OSF), and OSCC associated with OSF (OSCCOSF). MATERIALS AND METHODS: Formalin-fixed and paraffin-embedded tissue blocks of 30 OSF cases, 15 OSCCOSF cases, and 15 normal oral mucosae were obtained. Immunohistochemical staining was done with antibodies to CD34 to assess the vasculature and telocytes. The mean vascular density (MVD) and mean telocyte density were compared between the groups using the Kruskal-Walli test. RESULTS: A statistically significant high MVD (3.4 ± 1.22) and mean telocyte density (3.8 ± 1.35) was observed in OSCCOSF cases while it was lowest in advanced OSF cases. MVD was higher in early OSF cases than in normal mucosa. CONCLUSION: This study showed a decrease in CD34-positive telocytes in OSF, indicating that telocyte loss promotes the development of fibrosis.Increased angiogenesis coexisted with an increase in telocytes in OSCCOSF.

Malignant Transformation of Plexiform Neurofibroma Due to Neglected Giant Soft Tissue Swelling of the Back: A Case Report.

Neurofibromatosis type 1 can be severe and associated with malignant transformation. Proper follow-up and monitoring are very important in preventing the malignant transformation of neurofibromatosis. We encountered a case of malignant transformation of plexiform neurofibroma into neurofibrosarcoma (also known as malignant peripheral nerve sheath tumor). She had been presenting with a large mass on her back for a few years, which was also associated with an ulcer. She underwent a wide-excision biopsy of her back, and the histopathology examination (HPE) came back with a malignant peripheral nerve sheath tumor. This case concludes that any patient with a known case of neurofibromatosis should undergo follow-up to detect any malignant transformation of the disease. Early detection of the malignant transformation of neurofibromatosis can help prevent the disease's progression. The main treatment is surgical resection; however, the risk of local recurrence is higher, especially in patients with neurofibromatosis type 1.

Controversies regarding oral lichen planus and lichenoid-dysplastic lesions.

Objective: Oral lichen planus (OLP) is an immune-mediated condition featuring chronic inflammation. The World Health Organization classifies OLP as potentially malignant, but it is believed that the malignant transformation of OLP occurs in lesions with both lichenoid and dysplastic features (LD). This review discusses the issues surrounding OLP and LD, including their malignancy, classification, and categorization, and whether lichenoid inflammation causes dysplastic changes in LD or vice versa. Methods: English full-text literature on OLP, LD and/or dysplasia was retrieved from PubMed, CINAHL, and Google Scholar. Results: Thirty-six publications including original research articles, reviews, meta-analyses, books, reports, letters, and editorials were selected for review. Discussion: Research suggests that OLP has malignant potential, although small, and that LD should not be disregarded, as dysplasia presenting with or without lichenoid features may develop into cancer. There is also disagreement over the classification and categorization of LD. Different terms have been used to classify these lesions, including lichenoid dysplasia, OLP with dysplasia, and dysplasia with lichenoid features. Moreover, in LD, it is not clear if dysplasia or lichenoid infiltration appears first, and if inflammation is a response to dysplasia or if dysplasia is a response to the persistent inflammation. The main limitation in the literature is the inconsistency and subjective nature of histological diagnoses, which can lead to interobserver and intraobserver variation, ultimately resulting in the inaccurate diagnosis of OLP and LD. Conclusion: Although further research is required to understand OLP and LD, both lesions should be considered potentially malignant and should not be disregarded.

Objectif: Le lichen plan buccal (LPB) est une pathologie auto-immune qui se présente sous la forme d'une inflammation chronique. Selon la classification de l'Organisation mondiale de la santé, le LPB est une pathologie potentiellement maligne. Toutefois, on soupçonne que la transformation maligne du LPB se produit dans des lésions présentant à la fois des caractéristiques lichénoïdes et dysplasiques (LD). Cet examen porte sur les questions relatives au LPB et aux LD, notamment leur malignité, leur classification et leur catégorisation, et pour savoir si l'inflammation du lichénoïde entraîne des changements dysplasiques des LD ou vice versa. Méthodes: On a utilisé le texte intégral de documents rédigés en anglais sur le LPB, les LD et la dysplasie issus de PubMed, de CINAHL et de Google Scholar. Résultats: Trente-six publications, notamment des articles sur des études originales, des revues, des méta-analyses, des livres, des rapports, des lettres et des éditoriaux, ont été sélectionnées aux fins d'examen. Discussion: Des études suggèrent que le LPB est potentiellement malin, bien que ce potentiel soit faible, et que les LD ne doivent pas être ignorés : en effet, une dysplasie peut évoluer en cancer, qu'elle présente des caractéristiques lichénoïdes ou non. On constate également un désaccord quant à la classification et à la catégorisation des LD. Différents termes ont été utilisés pour la classification de ces lésions, notamment « dysplasie lichénoïde ¼, « LPB dysplasique ¼ et « dysplasie à caractéristiques lichénoïdes ¼. De plus, dans le cas des LD, on ne sait pas avec certitude si la dysplasie ou l'infiltration lichénoïde apparaît en premier, ni si l'inflammation découle de la dysplasie ou si la dysplasie est une conséquence de l'inflammation persistante. La principale limite de la littérature est due aux incohérences et à la nature subjective des diagnostics histologiques, qui peut entraîner des variations d'un observateur à l'autre ou même avec un même observateur, ce qui entraîne à terme des diagnostics erronés de LPB et de LD. Conclusion: Bien que d'autres études soient nécessaires pour comprendre le LPB et les LD, les lésions de ces 2 catégories doivent être considérées comme potentiellement malignes et ne doivent pas être ignorées.

Mucinous intestinal adenocarcinoma arising from mature cystic teratoma of the ovary treated with FOLFOX-6 - a case report.

The malignant transformation of mature cystic teratomas during pregnancy is a rare occurrence in medical literature. In this case report, we present a remarkable instance of mucinous intestinal adenocarcinoma arising from a mature ovarian cystic teratoma diagnosed during pregnancy. This is among the few reports detailing the effective use of the FOLFOX 6 chemotherapy regimen for treating this type of intestinal cancer. Furthermore, we emphasize the immunohistochemical results that confirm the colorectal histological origin.

Benign to Malignant, Malignant to Metastatic: Phyllodes Tumor Biology Transformation.

Phyllodes tumors (PTs) of the breast are rare fibroepithelial neoplasms, typically characterized by their benign nature. We present a unique case of a 29-year-old Pakistani female who initially presented with a benign PT in her left breast. Despite undergoing multiple surgical resections over the course of a decade, the tumor exhibited a remarkable transformation in biology, progressing from a benign phenotype to malignancy. Subsequent recurrences manifested with increasing aggressiveness, ultimately culminating in distant metastasis to the bones, axillary nodes, chest wall, and abdominal wall. This case underscores the unpredictable nature of PTs and highlights the challenges in managing recurrent cases with malignant transformation. The clinical course described herein emphasizes the importance of vigilant monitoring and individualized treatment strategies in such cases.

Right atrial cardiac myxoma with malignant transformation to undifferentiated sarcoma: A case report.

Generally, sarcomas arising from benign soft tissue are rare. Cardiac myxoma (CM) is a benign tumor, and few reports have described its malignant transformation. Herein, we documented a case of an 89-year-old man with prostate cancer and a 5-year history of a right atrium tumor without Carney complex. The tumor was resected surgically and had a myxomatous or gelatinous appearance. Microscopically, the tumor had two components: a sarcomatous area and myxomatous area. In the myxomatous area, typical myxoma cells were demonstrable and were strongly immunoreactive for immunohistochemistry (IHC) of calretinin. In the sarcomatous area, the epithelioid- to spindle-shaped cells with prominent atypia proliferated densely. The IHC profile of cells in the sarcomatous area was different from that of cells in the myxomatous area; MDM2-positive cells were found only in the sarcomatous area. Especially, the Ki-67 index and number of p53-positive cells in the sarcomatous area were higher than those in the myxomatous area. The transition of the two components was seamless. Thus, we made a diagnosis of CM with malignant transformation corresponding to undifferentiated pleomorphic sarcomas. This case suggests that CM may transform into sarcoma, albeit rarely.

Sustained high expression of NRF2 inhibits cell apoptosis in arsenite-transformed human keratinocytes.

Our previous study identified that nuclear factor-erythroid-2 p45-related factor 2 (NRF2) was activated in arsenite-induced tumorigenesis. However, the underlying mechanisms of NRF2 mediating apoptosis in arsenic-induced skin carcinogenesis remain unknown. This study explored the dynamic changes in apoptosis rate and the expression of apoptosis proteins in immortalized human keratinocytes (HaCaT) malignant transformation caused by 1.0 µM NaAsO2 at passages 0, 1, 7, 14, 21, 28, and 35. The result showed that the apoptosis rate decreased. The apoptosis-related proteins cleaved-caspase-3/caspase-3 ratio decreased in the later stages (passages 21, 28, and 35). Moreover, the expression of intrinsic ER stress pathway-related CHOP, ATF4, ATF6, and the intrinsic mitochondrial pathway-related Bax protein decreased in the later stages, while Bcl-2 and Mcl-1 increased, and NRF2 protein levels also increased. The apoptosis rate increased by silencing NRF2 expression in arsenite-transformed HaCaT (T-HaCaT) cells. Meanwhile, the expression of pro-apoptotic proteins (cleaved-caspase-3/caspase-3, CHOP, Bax) and ATF4, ATF6 increased. On the contrary, antiapoptotic protein levels (Bcl-2 and Mcl-1) decreased. The ability of colony formation and migration of T-HaCaT cells decreased. In conclusion, arsenite activated NRF2 in the later stages, decreasing apoptosis characterized by inhibiting endoplasmic reticulum stress-depended and mitochondria-depended apoptosis pathway, and further promoting NaAsO2-induced HaCaT cellular malignant transformation.

Transformation of a Benign Adrenocortical Adenoma to a Metastatic Adrenocortical Carcinoma Is Rare But It Happens.

The transformation of an adrenocortical adenoma (ACA) to an adrenocortical carcinoma (ACC) is extremely rare. Current guidelines suggest against further imaging studies and follow-up in patients with nonfunctional adrenal incidentalomas (NFAIs) with benign imaging characteristics. Herein, we present a 64-year-old male patient diagnosed initially with a NFAI of 3 cm in size with imaging characteristics consistent with an ACA. However, 13 years after initial diagnosis, this apparent ACA developed into a high-grade cortisol and androgen-secreting ACC with synchronous metastases. The literature review revealed a further 9 case reports of adrenal incidentalomas initially characterized as ACA that subsequently developed into ACC within a period ranging from 1 to 10 years. The pathogenesis of transformation of an initially denoted ACA to ACC is not fully delineated, although the existing literature focuses on the preexisting or changing genetic background of these lesions, highlighting the need to develop robust prognostic markers to identify patients at risk and individualize the follow-up of these unique cases.

Helicobacter pylori East Asian type CagA hijacks more SHIP2 by its EPIYA-D motif to potentiate the oncogenicity.

CagA is a significant oncogenic factor injected into host cells by Helicobacter pylori, which is divided into two subtypes: East Asian type (CagAE), characterized by the EPIYA-D motif, and western type (CagAW), harboring the EPIYA-C motif. CagAE has been reported to have higher carcinogenicity than CagAW, although the underlying reason is not fully understood. SHIP2 is an intracellular phosphatase that can be recruited by CagA to perturb the homeostasis of intracellular signaling pathways. In this study, we found that SHIP2 contributes to the higher oncogenicity of CagAE. Co-Immunoprecipitation and Pull-down assays showed that CagAE bind more SHIP2 than CagAW. Immunofluorescence staining showed that a higher amount of SHIP2 recruited by CagAE to the plasma membrane catalyzes the conversion of PI(3,4,5)P3 into PI(3,4)P2. This alteration causes higher activation of Akt signaling, which results in enhanced IL-8 secretion, migration, and invasion of the infected cells. SPR analysis showed that this stronger interaction between CagAE and SHIP2 stems from the higher affinity between the EPIYA-D motif of CagAE and the SH2 domain of SHIP2. Structural analysis revealed the crucial role of the Phe residue at the Y + 5 position in EPIYA-D. After mutating Phe of CagAE into Asp (the corresponding residue in the EPIYA-C motif) or Ala, the activation of downstream Akt signaling was reduced and the malignant transformation of infected cells was alleviated. These findings revealed that CagAE hijacks SHIP2 through its EPIYA-D motif to enhance its carcinogenicity, which provides a better understanding of the higher oncogenic risk of H. pylori CagAE.

Oral Lichen Planus and Its Therapeutic Approaches: A Case Report.

Lichen planus, a chronic inflammatory skin disorder, presents with pruritic, polygonal, and flat-topped papules and plaques. It encompasses not only the skin but also mucous membranes, nails, and hair follicles. Diagnosis relies on all the clinical and biopsy reports. The etiology of oral lichen planus (OLP) is multifactorial, with genetic, immunological, and environmental factors playing significant roles. Frequently utilized therapies encompass topical corticosteroids, calcineurin inhibitors, and systemic immunomodulatory medications. Management should be tailored to disease severity and the specific site of involvement. Lichen planus can present in papular, hypertrophic, atrophic, erosive, or erythematous forms. In this report, we present a case of a 28-year-old male patient who presented with bilateral white striations on the buccal mucosa and an erythematous lesion on the right buccal mucosa causing significant discomfort. The patient was treated with corticosteroids, resulting in marked symptomatic relief and partial lesion regression over a follow-up period of six months. This case underscores the importance of early diagnosis and tailored therapeutic strategies in managing OLP to improve patient outcomes.

Biomarkers of epithelial-mesenchymal transition: E-cadherin and beta-catenin in malignant transformation of oral lesions.

Objective: Detecting oral lesions at high risk of becoming cancer may enable early interventions to prevent oral cancer. The diagnosis of dysplasia in an oral lesion is used to predict this risk but is subject to interobserver and intraobserver variability. Studying biomarkers or molecular markers that reflect underlying molecular alterations can serve as an additional and objective method of risk assessment. E-cadherin and beta-catenin, molecular markers of epithelial-mesenchymal transition (EMT), potentially contribute to early malignant progression in oral tissue. This narrative review provides an overview of EMT, its relation to oral cancer, and the interaction among E-cadherin, beta-catenin, and the Wnt pathway in malignant progression of oral tissue. Methods: Full-text literature on EMT, E-cadherin, beta-catenin, oral epithelial dysplasia, and oral cancer was retrieved from PubMed and Google Scholar. Results: Sixty original research articles, reviews, and consensus statements were selected for review. Discussion: EMT, a biological mechanism characterized by epithelial and mesenchymal changes, can contribute to cancer development. Molecular markers of EMT including TWIST, vimentin, and N-cadherin may serve as prognostic markers of oral cancer. Dependent on Wnt pathway activity and the loss of membranous E-cadherin, E-cadherin and beta-catenin can play various roles along the spectrum of malignant progression, including tumour inhibition, early tumour progression, and late-stage tumour progression. Cross-sectional immunohistochemical research has found changes in expression patterns of E-cadherin and beta-catenin from normal oral tissue, oral epithelial dysplasia, to oral squamous cell carcinoma. Conclusion: Future research should explore the longitudinal role of EMT markers in predicting malignant progression in oral tissue.

Objectif: La détection de lésions buccales présentant un risque élevé d'évoluer en cancer peut permettre des interventions précoces pour prévenir le cancer de la bouche. Le diagnostic de dysplasie dans le cas de lésions buccales sert à prédire ce risque, mais il est soumis à une variabilité d'un observateur à l'autre et avec le même observateur. L'étude de marqueurs biologiques ou de marqueurs moléculaires correspondant à des altérations moléculaires sous-jacentes peut constituer une méthode objective supplémentaire d'évaluation des risques. L'E-cadhérine et la bêta-caténine, des marqueurs moléculaires de la transition épithélio-mésenchymateuse (TEM), pourraient contribuer aux premières étapes de l'évolution maligne du tissu buccal. Cette revue narrative donne un aperçu de la TEM, de ses liens avec le cancer de la bouche et de l'interaction entre l'E-cadhérine, la bêta-caténine et la voie de signalisation Wnt dans l'évolution maligne du tissu buccal. Méthodes: On a obtenu le texte intégral d'études portant sur la TEM, l'E-cadhérine, la bêta-caténine, la dysplasie épithéliale buccale et le cancer de la bouche sur PubMed et Google Scholar. Résultats: Soixante articles sur des études originales, des revues et des déclarations de consensus ont été sélectionnés aux fins d'examen. Discussion: La TEM, un mécanisme biologique caractérisé par des changements épithéliaux et mésenchymateux, peut contribuer à l'apparition d'un cancer. Les marqueurs moléculaires de la TEM, notamment TWIST, la vimentine et la N-cadhérine, peuvent servir de marqueurs pronostiques du cancer de la bouche. En fonction de l'activité de la voie de signalisation Wnt et de la perte de l'E-cadhérine membraneuse, l'E-cadhérine et la bêta-caténine peuvent jouer divers rôles dans le spectre de l'évolution maligne, notamment l'inhibition tumorale, la progression tumorale précoce et l'évolution tumorale avancée. Des études transversales d'immunohistochimie ont révélé des changements dans les modèles d'expression de l'E-cadhérine et de la bêta-caténine avec le passage du tissu buccal normal, de la dysplasie épithéliale buccale au carcinome squameux de la bouche. Conclusion: À l'avenir, des études devraient explorer le rôle longitudinal des marqueurs de la TEM dans la prévision de l'évolution maligne dans les tissus buccaux.

Diaphragmatic clear cell carcinoma with Lynch syndrome after surgery for atypical endometrial hyperplasia and ovarian endometriosis: A case report.

Clear cell carcinoma (CCC) of the diaphragm is rare, with an origin that is reported to be associated with malignant transformation of extraperitoneal endometriosis. Lynch syndrome (LS) is an autosomal dominant hereditary cancer syndrome caused by germline pathogenic variants in one of the DNA mismatch repair (MMR) genes, MLH1, MSH2, MSH6 and PMS2. Women with LS have a significantly increased lifetime risk of endometrial and ovarian cancer. CCC is a common histology of endometriosis- and LS-associated malignancy. The present study describes the case of a 51-year-old woman with an intra-abdominal mass found during a routine physical examination. The patient had undergone total hysterectomy and bilateral adnexectomy for atypical endometrial hyperplasia (AEH) and ovarian endometriosis, respectively, 3 years previously. Enhanced computed tomography showed a mass on the surface of the liver. Laparoscopic examination of the abdominal cavity revealed a tumor on the underside of the right diaphragm, which was then surgically excised. Pathological examination of the excised tumor, along with immunohistochemistry, led to a diagnosis of CCC. Since LS was suspected due to the genetic family history of the patient, microsatellite instability analysis was performed on the diaphragmatic tumor, and the results were positive. Immunohistochemistry was performed for MMR proteins in AEH and CCC cells, both of which revealed loss of MSH2 and MSH6 expression. Following detailed genetic counseling, genetic testing of MMR genes was performed, revealing a germline pathogenic variant in MSH2 (c.1000C>T, p.Gln344*), thus confirming the diagnosis of LS. To the best of our knowledge, this is the first case report of concurrent diaphragmatic CCC and LS. Patients with LS and endometriosis are at risk of developing ovarian cancer or intra-abdominal malignant tumors. In addition, immunohistochemistry screening for MMR proteins should be considered in patients with AEH and a family history of LS-related cancer, to enable early clinical intervention in cases of endometrial cancer.

MRI features of ovarian teratomas with somatic-type malignancy and mature cystic teratomas.

PURPOSE: We evaluated the magnetic resonance imaging (MRI) features of ovarian teratomas with somatic-type malignancy (TSMs) and benign ovarian mature cystic teratomas (MCTs) to determine the diagnostic contribution of the MRI findings for differentiating these two teratomas. METHODS: We compared the MRI findings between ovarian TSMs (n = 10) and MCTs (n = 193), and we conducted a receiver operating characteristic (ROC) analysis to determine the MRI findings' contribution to the differentiation of TSMs from MCTs. RESULTS: The maximum diameters of whole lesion and the largest solid component in the TSMs were larger than those of the MCTs (p = 0.0001 and p < 0.0001, respectively). Fat tissue in solid components was seen in 73/116 (62.9%) MCTs but in none of the TSMs (p = 0.0001). Ring-like enhancement in solid components was seen in 60/116 (51.7%) MCTs and none of the TSMs (p = 0.0031). On dynamic contrast-enhanced MRI (DCE MRI), all of the solid components in the TSMs showed a high- or intermediate-risk time intensity curve (TIC), and those in 113 of the 116 (97.4%) MCTs showed a low-risk TIC (p < 0.0001). The area under the curve of the ROC analysis using the high-/intermediate-risk TIC on DCE MRI was the highest (0.99) for differentiating TSMs from MCTs: sensitivity 100%, specificity 97.4%, positive predictive value 75.0%, negative predictive value 100%, and accuracy, 97.6%. CONCLUSION: Compared to ovarian MCTs, ovarian TSMs are larger and have larger solid components with high- or intermediate-risk TICs on DCE MRI. Ovarian MCTs frequently show small solid components with fat tissue, ring-like enhancement, and a low-risk TIC on DCE MRI.