Alexandra C Hristov

University of Colorado Denver, Denver, CO, USA

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Publications (10)27.51 Total impact

  • Article: Simplified flow cytometric assessment in mycosis fungoides and Sézary syndrome.
    Alexandra C Hristov, Eric C Vonderheid, Michael J Borowitz
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    ABSTRACT: By using flow cytometry with markers for CD3, CD4, CD26, and CD7, we examined the blood samples of 109 patients for abnormal T cells: 69 patients with mycosis fungoides (MF)/Sézary syndrome (SS), 31 hospitalized control subjects, and 9 patients with inflammatory skin disease. T cells were identified as quantitatively abnormal (>15% CD26- or CD7- T cells) or phenotypically abnormal (CD26- or CD7- T cells with bright or dim CD3 or CD4 or bright CD7). Patients were followed for a median of 82 months, and abnormal T cells were correlated with diagnosis, clinical outcome, and other laboratory parameters. Abnormal T-cell populations were identified in 46% of patients with MF/SS (32/69) and correlated with disease extent. Quantitative abnormalities were more frequent than phenotypic abnormalities, and CD4+/CD26- T cells were more frequent than CD4+/CD7- T cells. CD26- T cells correlated better with disease extent than did CD7 -. Increasing numbers of abnormal T cells were associated with worsening disease. Flow cytometry provides valuable information for diagnosis, prognosis, and therapeutic efficacy in MF/SS.
    American Journal of Clinical Pathology 12/2011; 136(6):944-53. · 2.60 Impact Factor
  • Article: A "high-risk" epithelioid hemangioendothelioma presenting as a solitary, ulcerated, subcutaneous tumor.
    Alexandra C Hristov, Joshua Wisell
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    ABSTRACT: So-called "high-risk" epithelioid hemangioendotheliomas are uncommon neoplasms that demonstrate classic histopathologic features of epithelioid hemangioendotheliomas and a size larger than 3 cm or >3 mitotic figures per 50 high power fields. These neoplasms show an increased rate of metastasis (25% of cases) and are associated with a poor 5-year survival (59%). They may pose a diagnostic challenge for dermatopathologists as they mimic metastatic carcinoma, malignant mixed tumor, melanocytic neoplasms, epithelioid sarcoma, and epithelioid angiosarcoma. High-risk epithelioid hemangioendothelioma has not been previously reported as a solitary ulcerated mass in the skin. Here, we describe one such lesion that developed as a rapidly growing ulcerative skin tumor in a 33-year-old African American man with a remote history of Burkitt lymphoma. We also review the evolution and controversies in the understanding and classification of this neoplasm.
    The American Journal of dermatopathology 12/2011; 33(8):e88-90. · 1.30 Impact Factor
  • Article: Localized cutaneous argyria.
    Alexandra C Hristov, Whitney A High, Loren E Golitz
    Journal of the American Academy of Dermatology 09/2011; 65(3):660-1. · 3.99 Impact Factor
  • Article: Auer rod-like inclusions in a low-grade B-cell leukemia.
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    ABSTRACT: Auer rods define neoplastic blasts of myeloid origin. However, azurophilic, needle-shaped, Auer rod-like inclusions have rarely been reported in the neoplastic cells of patients with B-cell malignancies, including chronic lymphocytic leukemia/small lymphocytic lymphoma. Here, we report a case of low-grade B-cell leukemia most consistent with chronic lymphocytic leukemia/small lymphocytic lymphoma that displayed numerous intracytoplasmic, needle-shaped, azurophilic rods resembling Auer rods. Furthermore, we review the literature on Auer rod-like structures in B-cell neoplasms.
    Annals of diagnostic pathology 08/2010; 14(4):292-5.
  • Article: HMGA1 correlates with advanced tumor grade and decreased survival in pancreatic ductal adenocarcinoma.
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    ABSTRACT: Although pancreatic ductal adenocarcinoma is a common and almost uniformly fatal cancer, little is known about the molecular events that lead to tumor progression. The high-mobility group A1 (HMGA1) protein is an architectural transcription factor that has been implicated in the pathogenesis and progression of diverse human cancers, including pancreatic ductal adenocarcinoma. In this study, we investigated HMGA1 expression in pancreatic ductal adenocarcinoma cell lines and surgically resected tumors to determine whether it could be a marker for more advanced disease. By real-time quantitative RT-PCR, we measured HMGA1a mRNA in cultured pancreatic ductal adenocarcinoma cell lines and found increased levels in all cancer cells compared with normal pancreatic tissue. To investigate HMGA1 in primary human tumors, we performed immunohistochemical analysis of 125 cases of pancreatic adenocarcinoma and 99 precursor lesions (PanIN 1-3). We found nuclear staining for HMGA1 in 98% of cases of pancreatic adenocarcinoma, but only 43% of cases of PanIN precursor lesions. Moreover, HMGA1 immunoreactivity correlates positively with decreased survival and advanced tumor and PanIN grade. These results suggest that HMGA1 promotes tumor progression in pancreatic ductal adenocarcinoma and could be a useful biomarker and rational therapeutic target in advanced disease.
    Modern Pathology 10/2009; 23(1):98-104. · 4.79 Impact Factor
  • Article: Extranodal Rosai-Dorfman disease involving the heart: report of two cases.
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    ABSTRACT: Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) is a rare disease that typically occurs in lymph nodes. While many body sites have been reported to be involved in extranodal manifestations of the disease, the cardiovascular system has been largely absent in this literature. We report two cases of Rosai-Dorfman disease that involves the heart. Case 1 was a 40-year-old man with chronic myelomonocytic leukemia who was incidentally noted to have Rosai-Dorfman disease on autopsy after succumbing to respiratory failure in the setting of adult respiratory distress syndrome. Case 2 was a 57-year-old woman known to have Rosai-Dorfman disease involving mediastinal lymph nodes and found to have a right atrial mass on workup for atypical chest pain. Both cases showed a similar histologic picture of large, multinucleated histiocytes with immunoreactivity to S100, emperipolesis, and marked plamacytosis. This study expands our knowledge of organs involved in extranodal Rosai-Dorfman disease.
    Cardiovascular pathology: the official journal of the Society for Cardiovascular Pathology 10/2009; 19(6):380-4. · 1.63 Impact Factor
  • Article: HMGA2 protein expression correlates with lymph node metastasis and increased tumor grade in pancreatic ductal adenocarcinoma.
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    ABSTRACT: Pancreatic ductal adenocarcinoma is a highly aggressive, lethal human malignancy that continues to elude successful treatment. Although most patients present with metastatic disease, the molecular pathways that underlie tumor progression and metastases are poorly understood. The high mobility group A2 (HMGA2) protein is an architectural transcription factor that has recently been implicated in the development and progression of malignant tumors. Here, we examined HMGA2 gene expression in pancreatic ductal adenocarcinoma to determine if it could be a marker for more advanced disease. By real time quantitative RT-PCR, we showed a marked increase in HMGA2 mRNA in two of three cultured pancreatic ductal adenocarcinoma cell lines compared to normal pancreatic tissue. Using tissue microarrays generated from 124 pancreatic ductal adenocarcinoma cases, we also assessed HMGA2 protein levels by immunohistochemical analysis. We found that HMGA2 nuclear immunoreactivity correlates positively with lymph node metastases and high tumor grade. Our results support a role for HMGA2 in the progression of pancreatic ductal adenocarcinoma and suggest that it could be a useful biomarker and rational therapeutic target in more advanced disease.
    Modern Pathology 09/2008; 22(1):43-9. · 4.79 Impact Factor
  • Article: Bordetella hinzii septicemia in association with Epstein-Barr virus viremia and an Epstein-Barr virus-associated diffuse large B-cell lymphoma.
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    ABSTRACT: We report the 1st case of Bordetella hinzii septicemia associated with Epstein-Barr virus viremia and lymphoma. B. hinzii identification necessitated cellular fatty acid analysis by gas-liquid chromatography and 16S rRNA gene sequencing. Isolates were resistant to many antimicrobials. Resistance and diagnostic challenges complicated management and contributed to mortality.
    Diagnostic Microbiology and Infectious Disease 09/2008; 61(4):484-6. · 2.53 Impact Factor
  • Article: Cytogenetic characterization of natural killer cell leukemia.
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    ABSTRACT: Natural killer (NK) cell neoplasms are rare neoplasms characterized by cells with NK characteristics. Few descriptions of the karyotype of this tumor are available. We describe a case with sequential analysis of the karyotype over a 3-month period. Cytogenetic analyses performed on specimens from the patient's peripheral blood and bone marrow generated similar results. Karyotype of the unstimulated peripheral blood at diagnosis was 46,XX,i(7)(q10),der(17)t(1;17)(q21;p11.1),-18,+mar[15]. Notably, a single cell with only an i(7q) was found, suggesting that this was the primary chromosomal abnormality in the neoplasm. The second specimen, 2 weeks later, was from bone marrow. Both the i(7q) and der(17) were present in two clones, which differed from each other in having two distinct derivative chromosomes 10. In one clone, the additional material on the short arm of chromosome 10 appears to have originated from either chromosome 1p or chromosome 22q, whereas for the second clone the donor of the additional material is most likely chromosome 8q. Thus, the karyotype for the bone marrow specimen is 46,XX,i(7)(q10),add(10)(p11.2),der(17)t(1;17)(q21;p11.1)[8]/46,XX,i(7)(q10),der(10)t(8;10)(q21;p12),der(17)t(1;17)(q21;p11.1)[3]/46,XX[14]. A final bone marrow specimen, after chemotherapy and shortly before the patient's death, showed abnormalities similar to those identified previously. The abnormalities seen in chromosomes 7 and 17 are consistent with previous reports of chromosomal abnormalities in NK-cell lymphomas.
    Cancer genetics and cytogenetics 07/2008; 183(2):125-30. · 1.54 Impact Factor
  • Article: Ovarian metastases of appendiceal tumors with goblet cell carcinoidlike and signet ring cell patterns: a report of 30 cases.
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    ABSTRACT: Synchronous and metachronous ovarian and appendiceal mucinous tumors are often the subject of diagnostic consultations in gynecologic pathology practices to address whether the tumors are independent neoplasms or related as primary and metastasis. Those with goblet cell carcinoidlike patterns have not been extensively evaluated in a large series. Clinicopathologic features of 30 cases were examined. All patients presented with signs or symptoms related to a pelvic/adnexal or abdominal mass. The ovarian tumors were bilateral in 25 of 28 cases with data on both ovaries and were typically large (mean/median: 14 cm, range: 4.5 to 24.0 cm). The appendices were often firm or thickened but usually did not have a discrete measurable tumor and were not notably enlarged; microscopically, transmural invasion was present in all of them. The ovarian and appendiceal tumors exhibited a variety of patterns of differentiation, including signet ring cell and glandular, with all displaying some goblet cell carcinoidlike patterns (nests, islands, cords, or cryptlike tubules with goblet cells); teratomatous elements were not identified in any ovarian tumors. Chromogranin was expressed in 7 of 19 ovarian tumors (mean/median: 6.3%/0%; range: 0% to 20%) and synaptophysin was expressed in 4 of 18 of these (mean/median: 7.8%/0%; range: 0% to 90%). Chromogranin was expressed in 6 of 16 appendiceal tumors (mean/median: 11.9%/0%; range: 0% to 70%) and synaptophysin was expressed in 6 of 15 of these (mean/median: 16.7%/0%; range: 0% to 90%). Follow-up was available for 25 patients: 17 died of disease at intervals ranging from 4 to 47 months (mean/median: 18/16) and 8 were alive with disease at 1 to 25 months (mean/median: 11/10); median survival was 19 months and the 1-year and 2-year survival rates were 63% and 34%, respectively. The clinicopathologic features of these ovarian tumors indicate they should be labeled as metastatic appendiceal adenocarcinomas rather than as goblet cell carcinoid tumors both to reflect their behavior and help distinguish them from the rare true primary ovarian goblet cell carcinoid tumors. As the ovarian tumors have appreciable components of signet ring cells they qualify as Krukenberg tumors. In cases in which the primary tumor is not already evident, their "goblet cell carcinoidlike" patterns should direct attention to the appendix as a possible source.
    American Journal of Surgical Pathology 11/2007; 31(10):1502-11. · 4.35 Impact Factor