The significance of enhancer of zeste homolog 2 (EZH2) expression in spindle cell lesions of the breast.

Spindle cell lesions of the breast are rare entities and pose a diagnostic challenge for pathologists due to overlapping morphologic and immunohistochemical features. We evaluated EZH2 expression in various benign (fibromatosis (n = 8), myofibroblastoma (n = 7), neurofibroma (n = 1), nodular fasciitis (n = 5), benign phyllodes tumor (n = 18)) and malignant (malignant phyllodes tumor (n = 8), metaplastic breast carcinoma (n = 16) and angiosarcoma (n = 8)) spindle cell lesions as a potential diagnostic and therapeutic marker. The EZH2 expression was evaluated semi-quantitatively to categorize the cases as 'low' and 'high' expression. All benign lesions showed low EZH2 expression, whereas high EZH2 expression was observed in the majority (28/32; 88%) of malignant lesions. The study results suggest that EZH2 may be used both as an additional diagnostic tool to reach an accurate diagnosis of the spindle cell lesions of the breast and as a therapeutic target for the malignant lesions.

High EZH2 expression in ductal carcinoma in situ diagnosed on breast core needle biopsy is an independent predictive factor for upgrade on surgical excision.

PURPOSE: Approximately 25 % of DCIS diagnosed on breast core needle biopsy (CNB) is upgraded to invasive carcinoma on surgical excision. Risk factors to predict the upgrade on excision are not well established, leading many patients to be over or under-treated. EZH2 was shown to be associated with aggressive behavior of cancer from many sites, including breast cancer. We aimed to analyze EZH2 expression and tumor infiltrating lymphocytes (TILs) in DCIS as predictive factors for an upgrade on excision. METHODS: We assessed EZH2 expression in 34 DCIS cases diagnosed on CNB and upgraded to invasive carcinoma on excision. Then, we compared these cases with 60 control cases that were not upgraded on excision. A staining score for DCIS (0-12) was obtained by multiplying the staining intensity (0-3) and the percentage of positive cells (1-4). The nuclear staining score ≥6 was considered as 'high' expression. RESULTS: 46 of 94 (49 %) DCIS on CNB showed high EZH2 expression. EZH2 expression was directly correlated with TILs density, nuclear grade, HER2 expression, Ki-67 index and negative ER status. On univariate analysis, upgrade on excision was associated with high EZH2 expression, high TILs density, negative ER status and high Ki-67 index. Multivariate analysis revealed the high EZH2 expression as the only independent predictive factor for upgrade on excision. CONCLUSIONS: Our study revealed the high EZH2 expression as the only independent predictive factor for an upgrade on excision. Future studies should focus on the evaluation of EZH2 expression in tumor-microenvironment interaction in terms of diagnostic, treatment and prognostic purposes.

Intratubular Teratoma: A Rare Form of Testicular Germ Cell Neoplasia.

Germ cell neoplasia in situ is the initial manifestation for invasive germ cell tumor. Further progression will result in intratubular germ cell tumor with the majority being intratubular seminoma or intratubular embryonal carcinoma. Intratubular teratoma in the testis is exceptionally rare with no well-documented cases to our knowledge. In this article, we report a case of an intratubular teratoma adjacent to mixed germ cell tumor in the testis. The patient is a 34-year-old male who presented with a palpable right testicular mass and underwent right radical orchiectomy. Gross examination of the testis revealed 2.0-cm tan, well-circumscribed, firm, and nodular mass at the inferior pole. Microscopic examination revealed a mixed germ cell tumor, predominantly seminoma (95%) with embryonal carcinoma (4%) and teratoma (1%). There is also germ cell neoplasia in situ, intratubular seminoma, and intratubular teratoma at the periphery of the tumor. Tubules with intratubular teratoma were filled by neoplastic squamous cells with a single layer of germ cell neoplasia in situ at the periphery. Adjacent to the intratubular teratoma was seminoma, embryonal carcinoma, and invasive teratoma. Immunohistochemical stains showed the neoplastic squamous cells in the tubule to be positive for p40 and negative for OCT34 and D2-40. The single layer of germ cell neoplasia in situ at the periphery of the intratubular teratoma was negative for p40 and positive for OCT34 and D2-40. Although teratoma is a common component in an adult germ cell tumor, an intratubular manifestation is exceptional. The present case illustrates this rare finding.

Expression of GATA-3 in Testicular and Gynecologic Mesothelial Neoplastic and Non-neoplastic Tissues.

GATA-3 expression in testicular/gynecologic mesothelial neoplasms and benign mesothelia have not been completely investigated. We graded GATA-3, calretinin, and WT1 staining in 20 adenomatoid tumors [9/20 (para)testicular and 11/20 tubal/uterine] and 38 normal mesothelia (20/38 tunica vaginalis and 18/38 fallopian tubes) as either 0 (≤5%), +1 (>5% and <25%), +2 (≥25% and ≤50%), and +3 (>50%). Adenomatoid tumor GATA-3 staining: 2 urologic cases were positive (2/9, +3 and +1), no gynecologic cases were positive (0/11), and all were positive for WT1/calretinin (20/20,+2 to +3). The normal tunica vaginalis mesothelia: 3 of 20 were GATA-3 positive (+2) while 20 of 20 were WT1/calretinin (+2 to +3) positive. The gynecologic cases with walthard nests: are positive for GATA-3 (18/18,+3), WT1 (11/18, +2 to +3), and calretinin (1/18,+2). The nonmetaplastic gynecologic mesothelia were GATA-3 negative (18/18) and WT1/calretinin postive (18/18,+2 to +3). All 18 epididymi were GATA-3 positive (+3) and negative for WT1/calretinin. All 11 efferent ductules examined were negative for GATA-3, WT1/calretinin (0/11). Although GATA-3 rarely stains adenomatoid tumors, gynecologic walthard nests are consistently positive with GATA-3 staining but lose mesothelial markers reflecting a metaplastic change. Excluding the walthard nests, GATA-3 is rarely positive in normal urologic and gynecologic mesothelia. GATA-3 is uniformally positive in epididymi and negative in efferent ductules, which may be due to their embryological evolvement. Awareness of the GATA-3 staining patterns in the genitourinary and gynecologic mesothelial tissues and their respective neoplasms is important to prevent misdiagnosis and possible unnecessary interventions.

Scanning electron microscopy of peripheral blood smears: comparison of normal blood with some common leukemias.

Peripheral blood smears prepared routinely from nonneoplastic and leukemia cases were studied using the scanning electron microscope (SEM). The peripheral blood glass slide is examined directly in the SEM following application of a thin carbon coat. The morphology of the nonneoplastic and neoplastic smears is described in detail utilizing the SEM secondary electron detector and backscattered electron detectors. Certain cell features are measured as well with the use of the measuring software resident in the SEM. The appearance of the SEM images of peripheral smear slides is compared to that of slides from fixed, processed, and sectioned bone marrow cases previously reported. The problem of cell constituent loss and overall shrinkage in the routinely processed and sectioned material is noted. The lack of these problems in the peripheral blood smear slides and their better appearance is emphasized. The resemblance of neoplastic cells to their normal counterparts is discussed. The monoblast resembles the normal monocyte but both cell size and nuclear size are greater; the moderately reticulated nuclear chromatin distinguishes the monoblast. Neoplastic lymphoid cells maintain the wispy extensions of the cytoplasm perimeter resembling microvilli and thereby differ from myeloid and monocytic cells. The neoplastic lymphoid cell shows coarse clumping of nuclear chromatin and in some instances coarse chromatin anastomoses to distinguish it from the normal lymphocyte. Lymphoid cells of acute lymphoblastic leukemia are 33% larger than those of chronic lymphocytic leukemia and normal lymphocytes. The neoplastic myeloblast has a finely granular nuclear chromatin, maintains a smooth cytoplasmic perimeter, and may show cytoplasmic reticulations. The myeloblast differs from the lymphoblast in that the former has a smooth cytoplasm perimeter. Further, myeloblasts show nuclear lobulations more frequently than lymphoblasts. Comparison of SEM findings with the three case studies by flow cytometry indicates satisfactory correlation. In case 15, flow cytometry indicated a monocyte subset positive for CD14 and CD64 among the neoplastic myeloid forms. A candidate for such a cell is recognized morphologically as well. The availability for SEM ultrastructural study of all the cells, both neoplastic and nonneoplastic, on a routine diagnostic smear slide is emphasized.