Undifferentiated-dedifferentiated endometrial carcinoma; the reappearance of an old friend with insights into the new data.

Endometrial carcinoma is a common malignancy in women and shows increasing incidence. Except for its two main pathogenetic types I and II, the continuing evolution on molecular genetics have led to a new classification system (TCGA), that includes four main molecular subtypes: (i) POLE-mutant (ultramutated), (ii) hypermutated (MSI), (iii) copy-number low/MSS (p53wt) and (iv) copy-number high/serous-like (p53mut). The undifferentiated and dedifferentiated endometrial carcinomas are rare and clinically aggressive variants, comprising about 10% of the high-grade endometrial carcinomas and 2% of the endometrial carcinomas in general. Until recently, they were under-recognized and not fully described morphologically and immunohistochemically/molecularly. Their recognition diagnostically is crucial because of their poor prognosis; approximately 40% of patients with these subtypes will die within 0.5-20 months after diagnosis, so additional therapeutic strategies are important for an effective management. Because of their rarity, the responsiveness to other than conventional treatment, such as immunotherapy, has not been sufficiently investigated yet. The aim of this review is to provide an update on the knowledge about these two uncommon subtypes according to the current literature.

Surgical administration of multiple glomus tumors in uncommon anatomic regions in a 17-year-old female. A rare case report.

Glomus tumor (GT) constitutes a rare, benign, soft-tissue tumor emerging from neuro-myo-arterial glomus bodies. Due to its rarity, and absence of typical symptoms, GT is usually misdiagnosed, with a potential risk of rupture and infection, or even malignant transformation. The present manuscript reports a rare case of a 17-year-old young woman with multiple GTs in her lower back, breach and left thigh that was surgically treated. The manuscript aims to highlight the importance of prompt diagnosis and surgical treatment of this peculiar tumor in young patients and raise surgeons' awareness.

Soft Tissue Myoepithelial Carcinoma Metastatic to the Cecum: Highlighting an Unusual Metastatic Pattern and the Need for Diagnostic Awareness.

Myoepithelial neoplasms of the soft tissues are a rare, heterogeneous group of tumors for which classification continues to evolve. While well defined within salivary glands, they can also arise in viscera and soft tissues, where diagnosis is challenging due to the lack of clinical and pathological familiarity. We present the case of a 36 year old man with myoepithelial carcinoma arising as a primary tumor within the soft tissues of the neck, which metastasized to the cecum, causing intussusception. This spindle cell neoplasm showed the classic S100 protein, smooth muscle actin and pancytokeratin-positive immunoprofile. Metastasis of myoepithelial carcinoma to the cecum has not been previously described, and coupled with the spindle cell morphology, may cause significant diagnostic difficulty in the absence of clinical familiarity, particularly as there is morphologic overlap with spindle cell neoplasms arising more commonly in gastrointestinal sites, including gastrointestinal stromal tumor, leiomyosarcoma and sarcomatoid carcinoma.

Solid Variant of Adenoid Cystic Carcinoma: Difficulties in Diagnostic Recognition.

Adenoid cystic carcinoma (ACC) is a malignant neoplasm that mainly affects the salivary glands but has been described in many other anatomical sites. It is composed of basaloid cells with myoepithelial/basal cell differentiation and ductal epithelial cells that proliferate in a fibrous stroma, with variable amounts of myxohyaline material. Three patterns (cribriform, tubular, and solid) occur, and the solid variant is characterized by a predominant compact sheet-like and nested pattern of rounded basaloid cells lacking obvious cribriform or tubular architecture. The solid variant has significant morphological and immunohistochemical overlap with a large range of neoplasms of different lineages, including other carcinomas and sarcomas. We describe a case of solid variant ACC of the paranasal sinuses, which showed an almost entirely solid pattern of growth (in >95% of cells) and which on initial biopsy showed no features of classical ACC. This highlights the potential for diagnostic misinterpretation with a variety of other neoplasms, which is particularly important because of the significant difference in treatment for ACC and tumors in its differential diagnosis.

Evaluation of Molecular and Immunohistochemical Adjunct Modalities in the Diagnosis of Soft Tissue Neoplasms.

The accurate diagnosis of soft tissue neoplasms has crucial therapeutic and prognostic importance. There is frequent morphologic overlap between entities, and ancillary modalities are used in the vast majority of diagnoses. Immunohistochemistry is rapid and inexpensive, and in addition to the older markers that mainly detected cytoplasmic proteins, antibodies can indirectly detect tumor-specific genetic and molecular abnormalities. The use of molecular diagnostic techniques is now widespread, with molecular services often integrated into routine histopathology laboratories; as their cost and turnaround times begin to parallel those for immunohistochemistry, we compared the usefulness of ancillary immunohistochemistry, molecular genetic, and molecular cytogenetic techniques in the diagnosis of soft tissue lesions. We evaluated the number and contribution of immunohistochemical tests and panels and of ancillary molecular techniques in the primary histopathologic diagnosis of 150 soft tissue lesions. Ninety of 150 cases required either only one immunohistochemical panel or minimal immunohistochemistry for diagnosis, while 39/150 required 2 to 4 panels. In 5/150, ancillary molecular tests alone (without immunohistochemistry) were diagnostically sufficient. The majority of cases required one immunohistochemical panel for diagnosis, with a smaller proportion requiring a second, and a minority requiring a third or fourth (which mainly comprised neoplasms for which the final diagnosis was uncertain). Certain neoplasms required both extensive immunohistochemistry and ancillary molecular testing, despite which the final diagnosis was inconclusive. Ancillary molecular techniques now make a significant contribution to soft tissue tumor diagnosis, being required in over one third (52/150) of cases, and were useful in confirming or excluding tumors that were not possible to conclusively diagnose with histology and immunohistochemistry. Only a small proportion of soft tissue neoplasms (16/150; all benign) did not require immunohistochemistry or ancillary molecular methods, with morphology alone being sufficient for diagnosis.

EZH2 is regulated by ERK/AKT and targets integrin alpha2 gene to control Epithelial-Mesenchymal Transition and anoikis in colon cancer cells.

Epithelial-Mesenchymal Transition is a good example of cell plasticity. In tumorigenesis, this process has been associated with metastasis. Overexpression of EZH2 has been detected in most malignant human tumors, including colorectal carcinomas. Herein, we provide evidence supporting the idea that oncogenic Epithelial-Mesenchymal Transition in colon cancer cell models is partially controlled by epigenetic factors such as the transcription regulator EZH2. Evaluation of EZH2 mRNA and protein levels revealed overexpression in cell lines with metastatic traits. Analysis of EZH2 mRNA expression was expanded in clinical samples of colon cancer, and high level of EZH2 correlates with appearance of metastasis. Furthermore, inhibition of ERK and AKT pathways in metastatic colon cancer cell lines attenuates EZH2 overexpression. EZH2 promoter analysis illustrates presence of putative AP-1 binding sites and occupancy of transcription factors such as FRA-1 and C-JUN is demonstrated here on EZH2 promoter. Abrogation of EZH2 expression impairs the ability of colon cancer cells to move associated with anoikis in three-dimensional environment. Integrin alpha2 was identified to be a novel EZH2 target by chromatin immunoprecipitation and short hairpin RNA analysis. This study proposes that activation of ERK/AKT pathways and FRA1/C-JUN induce EZH2 overexpression, which results in Integrin alpha2 silencing. Our results show how deregulation of epigenetic factors and mechanisms can affect cancer cell aggressiveness and propose EZH2 as a potential metastasis marker and/or therapeutic target for colorectal cancer treatment.