Extraordinary Case: Unique Presentation of an Aggressive Epstein-Barr Virus-Positive Mucocutaneous Ulcer.

ABSTRACT: Epstein-Barr virus-positive mucocutaneous ulcer is a recent and unusual type of lymphoproliferation, mostly associated with various forms of immunosuppression. In most cases, they regress spontaneously, but an increasing number of reports describe a spectral behavior of the lesion, which ranges from a simple ulcer with eosinophilia to aggressive ulcers. In these cases, Epstein-Barr virus-related lymphomas are the main differential diagnosis. We report a unique observation of this rare disease with mandibular involvement. Due to bone erosion, the patient was treated with 6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) with complete healing of the ulcer on clinical examination and PET-scan control.

Cyclin D1 expression in Rosai-Dorfman disease: a near-constant finding that is not invariably associated with mitogen-activated protein kinase/extracellular signal-regulated kinase pathway activation.

Activating mutations in the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway have been shown in nearly half of the cases of Rosai-Dorfman disease (RDD). Cyclin D1, a key cell cycle regulator, constitutes a major downstream target of the MAPK/ERK pathway. In this study, we aim to further understand the pathogenesis of RDD by assessing the lesional histiocytes for cyclin D1, p-ERK, Ki-67, and BCL-2 by immunohistochemistry. We assessed 35 samples of RDD and a control group of histiocyte-rich reactive lesions. Cyclin D1 was expressed in about 90% of cases of RDD. Cyclin D1 was positive in 25-95% (median, 85%) of lesional histiocytes, was moderately/strongly expressed in 97% of cyclin D1-positive cases, and was significantly higher than in control specimens. p-ERK was positive in 16 of 30 (53%) cases of RDD and was negative in all controls. All p-ERK-positive RDD cases had concurrent cyclin D1 expression, whereas more than a third of cyclin D1-positive cases were negative for p-ERK. Ki-67 was low in RDD (median, 3%). BCL-2 was positive in lesional histiocytes in nine of 10 RDD cases assessed. Overall, these findings point to unexpected, potential roles of these molecules in the pathogenesis of RDD. Overexpression of cyclin D1 in the absence of ERK phosphorylation in a subset of RDD cases opens the possibility of oncogenic mechanisms bypassing ERK and supports the notion that cyclin D1 overexpression in RDD is multifactorial. Moreover, the observed lack of correlation between cyclin D1 with Ki-67 proliferative index suggests that prosurvival actions of cyclin D1 are, at least in part, cell cycle independent. Finally, expression of BCL-2 and the low Ki-67 index suggest that RDD might be driven by antiapoptotic rather than proproliferative oncogenic mechanisms.

Serpin peptidase inhibitor clade A member 1 as a potential marker for malignancy in insulinomas.

PURPOSE: The biological behavior of insulinomas cannot be predicted based on histopathologic criteria in which the diagnosis of malignancy is confirmed by the presence of metastases. In this study, microarray and quantitative real-time reverse transcription-PCR were applied to identify differentially expressed genes between malignant and nonmalignant insulinomas to search for useful biomarkers to recognize the metastatic potential of insulinomas. EXPERIMENTAL DESIGN: Code Link human bioarrays were used to analyze differences in approximately 20,000 genes between six well-differentiated endocrine tumors of benign behavior compared with one well-differentiated endocrine carcinoma (WDEC) and three metastases of endocrine carcinomas (MEC). Quantitative real-time reverse transcription-PCR was used to validate differential expressions of five genes in a series of 35 sporadic insulinomas. Serpin peptidase inhibitor clade A member 1 (SERPINA1; alpha-1-antitrypsin) expression, identified as up-regulated in malignant insulinomas, was also evaluated by immunohistochemistry. RESULTS: Analysis of microarray data resulted in 230 differentially expressed genes. Gene Ontology analysis identified serine-type endopeptidase activity and serine-type endopeptidase inhibitor activity as pathways presenting significant differential expression. Protease serine 2 and complement factor B (from serine-type endopeptidase activity pathway) were respectively confirmed as up-regulated in well-differentiated endocrine tumors of benign behavior (WDET) and in WDEC/MEC. Angiotensinogen and SERPINA1 (from serine-type endopeptidase inhibitor activity pathway) were confirmed as up-regulated in WDEC/MEC. SERPINA1 was shown to be expressed in 85.7% of malignant versus 14.3% of nonmalignant insulinomas by immunohistochemistry. CONCLUSIONS: Our data are consistent to the possibility that SERPINA1 is a marker of malignancy in insulinomas. Given the widespread availability of antibody anti-alpha-1-antitrypsin in pathology services, SERPINA1 expression evaluation might be of clinical utility in recognizing patients more likely to develop an aggressive presentation.

Contribution of immunohistochemistry to small B-cell lymphoma classification.

Although the small B-cell lymphomas show major morphologic overlapping, they have been recently shown to be distinct entities with several biologic and clinical differences. Therefore, the utility of a panel of paraffin-reactive antibodies in differentiating these neoplasms was investigated. Using clinical data and morphologic criteria, 134 cases of small B-cell lymphomas were grouped as those with (1) one strongly suggested diagnosis, (2) differential diagnosis between two types of lymphomas, and (3) small B-cell lymphoma without hints for further subclassification. With a panel of antibodies including CD5, CD10, CD23, CD43, bcl-2, and cyclin D1, most but not all cases could be precisely categorized. This panel confirmed the diagnosis in 96.5% of the cases from group 1. In group 2 it confirmed one of the two diagnoses in 81.5% of the cases. In group 3 it established a definitive diagnosis in 55% of the cases. When all groups were considered, a correct diagnosis could be established for 88.1% of cases; for 6.7% of them the authors remained with two possible diagnosis, and the broad "small B-cell lymphoma" was the only diagnosis for 5.2% of cases. CD10 separated most follicular lymphomas from other small B-cell lymphoid neoplasms. CD23 separated small lymphocytic lymphoma/chronic lymphocytic leukemia. Cyclin D1 separated mantle cell lymphoma. The present study selected CD10, CD23, and cyclin D1 as a minimal panel for the classification of small B-cell lymphomas, yielding a final diagnosis in 88.1% of the cases.

Cytologic findings of epithelioid angiosarcoma of the thyroid. A case report.

BACKGROUND: Angiosarcoma of the thyroid is a rare and aggressive tumor and occurs mainly in patients from central Europe, especially the alpine region. The fine needle aspiration findings of a keratin-positive epithelioid angiosarcoma of the thyroid occurring in a nonmountainous area in South America is described. CASE: A 65-year-old male from São Paulo, Brazil, presented with a mass in the anterior part of the neck with progressive enlargement for three months. The cytologic findings on the fine needle aspirate were a cellular smear composed of single cells and small clusters of neoplastic cells, oval and round. Cell borders were indistinct, and the cytoplasm was vacuolated. The nuclei were eccentrically located, with irregular nuclear membranes; single, prominent nucleoli; and a coarse chromatin pattern. Features suggestive of intracytoplasmic lumens were identified. Open surgical biopsy demonstrated a tumor infiltrating the thyroid gland and composed of large, round, atypical epithelioid cells lining vascular spaces. These neoplastic cells were immunoreactive for AE1:AE3, CK7, vimentin, CD31 and factor VIII. CONCLUSION: Epithelioid angiosarcoma should be considered in the differential diagnosis of epithelioid neoplasms of the thyroid. An immunohistochemical panel should include vascular markers even in the presence of immunoreactivity for epithelial markers.

Lymph node micrometastasis in stage II distal rectal cancer following neoadjuvant chemoradiation therapy.

OBJECTIVE: The objective was to determine the presence and frequency of micrometastasis in lymph nodes of patients with rectal cancer treated by preoperative chemoradiation followed by curative resection. PATIENTS AND METHODS: All 56 patients included were treated with 5-FU and leucovorin plus 5,040 cGy, followed by radical surgery and were diagnosed with stage II distal rectal adenocarcinoma after complete pathological examination (ypT3-4N0M0). Immunohistochemistry was assessed with cytokeratin monoclonal antibody AE1/AE3. Three 4-microm paraffin sections were obtained from each lymph node, cut at 50 microm apart from each other. The results were reviewed by two independent pathologists. RESULTS: Mean number of lymph nodes was 9.6 per patient. Four patients (7%) and seven lymph nodes (1.35%) were positive for micrometastasis. Three patients had pT3 and one a pT4 tumor. One of the patients had positive micrometastasis and the presence of mucinous deposits. One other patient had mucinous deposits without any micrometastasis. All four patients are alive with no evidence of recurrent disease. Fourteen patients negative for micrometastasis had recurrent disease (25%), eight systemic (14.7%) and six locoregional (10.3%). There were two cancer-related deaths. The mean follow-up period was 39 months. CONCLUSION: Patients with rectal cancer treated by preoperative chemoradiation showed a surprisingly low rate of micrometastasis detection (7%), even in high-risk patients (T3 and T4 tumors). Lymph node micrometastasis was not associated with decreased overall or disease-free survival. The identification of mucinous deposits on lymph nodes with no viable tumor cells may be direct evidence of lymph node downstaging. The downstaging effect of preoperative chemoradiation therapy may be significant in reducing even micrometastasis detection in low rectal cancer managed by this treatment strategy.