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Russell Vang

Publications and source records attributed to Russell Vang.

26 records · Page 2Linked to original sources
PubMed2004

Signet-ring stromal tumor of the ovary: clinicopathologic analysis and comparison with Krukenberg tumor.

Signet-ring stromal tumor is a rare ovarian neoplasm that can mimic Krukenberg tumor because of the presence of signet-ring cells in both tumors. The clinicopathologic features of three signet-ring stromal tumors, one of which has been previously reported, were analyzed and compared with 10 Krukenberg tumors. Patients with signet-ring stromal tumor ranged in age from 34 to 41 years (mean: 36.7 years). All signet-ring stromal tumors were unilateral and stage IA, whereas 60% and 40% of Krukenberg tumors were bilateral or associated with extraovarian tumor, respectively. The signet-ring stromal tumors were devoid of epithelial differentiation (glands, nests, cords), whereas all of the Krukenberg tumors contained these epithelial structures at least focally. In contrast to signet-ring stromal tumors, the signet-ring cells of Krukenberg tumors were positive for periodic acid-Schiff with diastase and cytokeratins but negative for vimentin. The patients with signet-ring stromal tumors were alive without disease at follow-up interval of 1 month to 17.4 years (mean: 7.4 years). In summary, signet-ring stromal tumor is a rare, benign, ovarian tumor that may be mistaken for Krukenberg tumor. Although the combination of operative and histopathologic findings allow their distinction, histochemical and immunohistochemical stains may also be useful.

Adult↗
PubMed2004

Immunohistochemical staining for Ki-67 and p53 helps distinguish endometrial Arias-Stella reaction from high-grade carcinoma, including clear cell carcinoma.

The distinction of the Arias-Stella reaction from clear cell carcinoma of the endometrium is usually straightforward; however, this differential diagnosis can be difficult when the Arias-Stella reaction occurs outside the setting of pregnancy or in older patients. The differential diagnosis also is problematic when serous or clear cell carcinoma focally arises within an endometrial polyp, as part of "endometrial intra-epithelial carcinoma" (EIC), or in younger patients. The goal of this study was to determine whether immunohistochemical staining can distinguish the Arias-Stella reaction from endometrial high-grade carcinoma, particularly clear cell carcinoma. Cases of endometrial Arias-Stella reaction (n = 27), clear cell carcinoma (n = 11), serous carcinoma (n = 7), and EIC (n = 4) were assessed by immunohistochemical staining with antibodies for Ki-67, p53, estrogen receptor (ER), and progesterone receptor (PR). Composite immunohistochemical scores based on the percentage and intensity of stained cells were calculated, as was the overall positivity (percentage positive cases), using a cutoff value of >/=5% stained cells and at least weak intensity. Appropriate statistical tests were performed. Ki-67 and p53 immunostaining was significantly less in Arias-Stella reaction than in clear cell carcinoma (p < 0.0001 for both) or serous carcinoma/EIC (p < 0.0001 for both), measured by the composite immunohistochemical scores or overall positivity. ER showed a significant difference only between Arias-Stella reaction and clear cell carcinoma; PR showed a significant difference only between Arias-Stella reaction and serous carcinoma/EIC. When clinical or histologic features cannot facilitate the differential diagnosis, immunohistochemical staining for Ki-67 and p53 may help distinguish endometrial Arias-Stella reaction from clear cell carcinoma and other types of high-grade carcinoma.

Adenocarcinoma, Clear Cell↗
PubMed2003

Cell clusters overlying focally disrupted mammary myoepithelial cell layers and adjacent cells within the same duct display different immunohistochemical and genetic features: implications for tumor progression and invasion.

INTRODUCTION: Our previous studies detected focal disruptions in myoepithelial cell layers of several ducts with carcinoma in situ. The cell cluster overlying each of the myoepithelial disruptions showed a marked reduction in or a total loss of immunoreactivity for the estrogen receptor (ER). This is in contrast to the adjacent cells within the same duct, which were strongly immunoreactive for the ER. The current study attempts to confirm and expand previous observations on a larger scale. METHODS: Paraffin sections from 220 patients with ER-positive intraductal breast tumors were double immunostained with the same protocol previously used. Cross-sections of ducts lined by > or = 40 epithelial cells were examined for myoepithelial cell layer disruptions and for ER expression. In five selected cases, ER-negative cells overlying the disrupted myoepithelial cell layer and adjacent ER-positive cells within the same duct were separately microdissected and assessed for loss of heterozygosity and microsatellite instability. RESULTS: Of the 220 cases with 5698 duct cross-sections examined, 94 showed disrupted myoepithelial cell layers with 405 focal disruptions. Of the 94 cases, 79 (84%) contained only ER-negative cell clusters, nine (9.6%) contained both ER-negative and ER-positive cell clusters, and six (6.4%) contained only ER-positive cell clusters overlying disrupted myoepithelial cell layers. Of the 405 disruptions, 350 (86.4%) were overlain by ER-negative cell clusters and 55 (13.6%) were overlain by ER-positive cell clusters (P < 0.01). Microdissected ER-negative and ER-positive cells within the same duct from all five selected cases displayed a different frequency or pattern of loss of heterozygosity and/or microsatellite instability at 10 of the 15 DNA markers. CONCLUSIONS: Cells overlying focally disrupted myoepithelial layers and their adjacent counterparts within the same duct displayed different immunohistochemical and molecular features. These features potentially represent an early sign of the formation of a biologically more aggressive cell clone and the myoepithelial cell layer breakdown possibly associated with tumor progression or invasion.

Breast↗
PubMed2003

A subset of morphologically distinct mammary myoepithelial cells lacks corresponding immunophenotypic markers.

INTRODUCTION: Immunostaining for smooth muscle actin (SMA) is commonly used to elucidate mammary myoepithelial (ME) cells, whose presence or absence is a reliable criterion for differentiating in situ and invasive carcinomas. However, some morphologically distinct ME cells fail to stain for SMA. This study intended to assess whether these SMA-negative cells also lack the expression of other ME cell markers. METHODS: Hematoxylin/eosin and SMA immunostained sections from 175 breast cancer patients were examined. Three cases were found to harbor ducts that showed morphologically distinct ME cell layers, but showed no SMA immunostaining in at least one-third of the layer or the entire layer. Eight additional consecutive sections from each case were stained for SMA, using a black chromogen, and each was then re-stained for one of eight additional markers supposed to exclusively or preferentially stain ME cells, using a red chromogen. SMA-negative ME cells were re-examined for the expression of other markers. RESULTS: SMA-negative ME cells in two cases also failed to display immunoreactivity for other markers, including calponin, CD10, smooth muscle myosin heavy chain, protease inhibitor 5 (maspin), Wilms' tumor-1, and cytokeratins 5, 14, and 17 (CK5, CK14, and CK17). However, in one case SMA-negative ME cells displayed immunoreactivities for maspin, CK5, CK14, and CK17. The distribution of these ME cells is independent of ductal size, length, and architecture. CONCLUSIONS: A subset of morphologically identifiable ME cells lack the expression of nine corresponding immunophenotypic markers, suggesting that ME cells might also be subject to different normal and pathological alterations.

Biomarkers, Tumor↗
PubMed2003

Proliferative mucinous lesions of the endometrium: analysis of existing criteria for diagnosing carcinoma in biopsies and curettings.

It is often difficult to make a diagnosis of carcinoma in endometrial biopsies and curettings that show proliferative mucinous lesions because of the deceptively bland appearance of invasive mucinous adenocarcinoma at this site. Only limited information is available regarding criteria for distinguishing mucinous carcinoma from atypical mucinous proliferations and mucinous metaplasia of the endometrium. The threshold for diagnosing mucinous carcinoma in endometrial biopsies/curettings may possibly be lower than that for endometrioid carcinoma. We evaluated different sets of existing criteria in order to determine which best facilitate a diagnosis of carcinoma in endometrial biopsies/curettings containing mucinous lesions. The biopsy/curetting samples with the corresponding uterus (hysterectomy performed within 6.5 months) from each of 31 patients were studied. The biopsies/curettings were assessed with previously published criteria that more typically are used for endometrioid proliferations, as well as recently proposed criteria for mucinous lesions (Mod Pathol 12:1137-1142, 1999; Nucci et al. criteria [Type A, B, or C]). The presence of myoinvasion in the uterus was used as the gold standard for testing the biopsies/curettings. The sensitivity and specificity of diagnosing carcinoma with use of endometrioid criteria were 20.0% and 71.4%, respectively, while the corresponding figures for diagnosing carcinoma with use of the criteria of Nucci et al. were 0% and 81.0% (Type A), 70.0% and 52.4% (Type B), and 30.0% and 66.7% (Type C), respectively. Combining the Types B and C criteria of Nucci et al. into a single category (Combined Type B or C) yielded a sensitivity and specificity of 100% and 19.0%, respectively, for diagnosing carcinoma. With use of a diagnosis of carcinoma by endometrioid criteria and application of the criteria of Nucci et al. for mucinous lesions, myoinvasive carcinoma was present in the uterus in 25.0% (endometrioid criteria) and 0%, 41.2%, 30.0%, and 37.0% (Types A, B, C, and Combined Type B or C, respectively) of cases, respectively. Because of the high sensitivity/low specificity of the criteria of Nucci et al. and low sensitivity/high specificity of endometrioid criteria in this small study, neither of the sets tested is perfect for handling mucinous proliferations. However, the criteria of Nucci et al. do have utility. Application of the criteria available for endometrioid proliferations in biopsies/curettings that show mucinous lesions may be misleading.

Adenocarcinoma, Mucinous↗
PubMed2002

Solitary fibrous tumor of the tongue: report of a case with immunohistochemical and ultrastructural studies.

Solitary fibrous tumors are rare in extrapleural sites and extremely rare in the oral cavity. We report a case of a solitary fibrous tumor arising from the tongue of a 70-year-old woman. The tumor measured 1.6 cm in maximum diameter and consists of spindle-shaped cells distributed in a haphazard pattern. Immunohistochemical studies show strong positivity for CD34 and bcl-2, and weak positivity for desmin. Smooth muscle actin and S-100 protein are negative. Electron microscopy shows uniform neoplastic spindle cells with mesenchymal features. The differential diagnosis for spindle cell neoplasms in the tongue is discussed.

Aged↗
PubMed2002

Perivascular epithelioid cell tumor ('PEComa') of the uterus: a subset of HMB-45-positive epithelioid mesenchymal neoplasms with an uncertain relationship to pure smooth muscle tumors.

The family of lesions thought to be composed at least in part of perivascular epithelioid cells, characterized as HMB-45-positive epithelioid cells with clear to eosinophilic granular cytoplasm and a propensity for a perivascular distribution, includes some forms of angiomyolipoma and lymphangioleiomyomatosis, as well as clear cell "sugar" tumor (CC-SUGAR). When composed predominantly or exclusively of epithelioid cells, it has been suggested that these lesions be classified as "perivascular epithelioid cell tumors" (PEComa). Four cases of uterine PEComa have been described in the literature, three of which exhibited aggressive behavior. We report the clinical, histologic, and immunohistochemical features of eight more examples of uterine PEComa. Patients ranged in age from 40 to 75 years (mean 54 years). Most patients presented because of abnormal uterine bleeding, and grossly a mass was present in the uterine corpus. Morphologically, the tumors could be divided into two groups (A and B). Group A tumors demonstrated a tongue-like growth pattern similar to that seen in low-grade endometrial stromal sarcoma and were composed of cells that tended to have abundant clear to eosinophilic pale granular cytoplasm, diffuse HMB-45 expression, and focal muscle marker expression. Group B tumors were composed of epithelioid cells with less prominent clear cell features, smaller numbers of which were HMB-45-positive. They also featured extensive muscle marker expression and a lesser degree of the endometrial stromal sarcoma growth pattern seen in group A tumors. Two of the four patients with group B tumors had pelvic lymph nodes involved by lymphangioleiomyomatosis, and one of these patients had the tuberous sclerosis complex. Seven of the eight patients with PEComas were treated by hysterectomy. All eight patients are alive and well, although follow-up of >2 years was available only for two patients. Uterine epithelioid smooth muscle tumors and low-grade endometrial stromal sarcomas were compared with the PEComas. Group A PEComas, group B PEComas, and epithelioid smooth muscle tumors were all parts of a continuous histologic spectrum, with group A PEComa at one end of the spectrum and epithelioid smooth muscle tumors at the other, while group B tumors shared features of both. PEComa was histologically and immunohistochemically distinct from endometrial stromal sarcoma. Our data and a review of the literature indicate that PEComa is a subset of HMB-45-positive epithelioid mesenchymal tumors of the uterus with an uncertain relationship to pure smooth muscle tumors. Although none of the patients in this study experienced recurrence during a short follow-up period, some reported in the literature have had recurrences; consequently, we think uterine PEComa should be considered a tumor of uncertain malignant potential until long-term outcome data for a larger number of patients become available.

Adult↗