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Dive into the research topics where Marcelo Alvarenga is active.

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Featured researches published by Marcelo Alvarenga.


Virchows Archiv | 2005

p63, cytokeratin 5, and P-cadherin: three molecular markers to distinguish basal phenotype in breast carcinomas

Irina Matos; Rozany Mucha Dufloth; Marcelo Alvarenga; Luiz Carlos Zeferino; Fernando Schmitt

Human breast carcinomas represent a heterogeneous group of tumors diverse in behavior, outcome, and response to therapy. However, the current system of pathological classification does not take into account biologic determinants of prognosis. The purpose of this study was to classify and characterize breast carcinomas based on variations in protein expression patterns derived from immunohistochemical analyses on tissue microarrays (TMAs). Therefore, 11 TMAs representing 168 invasive breast carcinomas were constructed. Breast tumors were classified into four different subtypes depending on estrogen receptor (ER) and HER2 expression. Basal-type tumors expressed neither of these proteins and represented 7.6% of our series; basal-like HER2-overexpressing tumors did not express ER and represented 17.7%; luminal-type tumors expressed ER and represented 72.8% of this series (luminal A 56.3%, luminal B 16.5%). Moreover, we characterized each subtype based on P-cadherin (P-CD), p63, cytokeratin (CK)5, BCL2, and Ki67 expression. Basal-type tumors were mostly grade III, more frequently P-CD-, p63-, and CK5-positive, and had a high proliferation rate. Conversely, luminal-type tumors rarely expressed basal markers and had a low grade and proliferation rate. Basal-like HER2-overexpressing tumors showed a basal-type profile similar with a high grade and up-regulation of P-CD and CK5. With this study, we show that P-CD, p63, and CK5 are important molecular markers that can be used to distinguish a basal phenotype. In addition, we also demonstrate the usefulness of TMAs in breast carcinoma immunoprofiling.


Annals of Surgical Oncology | 2005

Evaluation of Residual Glandular Tissue After Skin-Sparing Mastectomies

Renato Zocchio Torresan; César Cabello dos Santos; Hélio Okamura; Marcelo Alvarenga

BackgroundThe oncological safety of skin-sparing mastectomy (SSM) has been the object of several studies.MethodsFrom June 2003 to January 2004, 42 breast cancer patients, stage 0 to IIIA, underwent SSM. Before surgery, two lines were drawn on the breast skin, representing SSM and conventional mastectomy incisions. After surgery, the skin flap that would remain after SSM was removed, and immediate breast reconstruction was begun. The presence and amount of remaining glandular breast tissues were histologically evaluated in the skin flap. Terminal ductal lobular units (TDLUs) and residual disease were identified. These data were correlated with other clinical and pathologic parameters by using Fisher’s exact test (P value) and receiver operating characteristic curves.ResultsThe prevalence of residual breast tissue in the sample was 59.5%, and the presence of TDLUs was significantly associated with skin flaps thicker than 5 mm. Residual disease was found in 9.5% of the women and was associated with skin flaps >5 mm thick and the presence of TDLUs. There was no significant association between the presence of TDLUs and residual disease with age, body mass index, menopausal status, clinical and pathologic staging, breast volume, mammographic density, neoadjuvant chemotherapy, type of surgery, and presence of an extensive in situ component. The receiver operating characteristic curve showed that as skin flaps decrease in thickness, TDLUs also decrease.ConclusionsA high prevalence of glandular breast tissue and residual disease in the skin flap was associated with a skin flap thickness >5 mm.


Modern Pathology | 2007

Renal medullary carcinoma: report of seven cases from Brazil

Isabela C. Watanabe; Athanase Billis; Marbele S. Guimaraes; Marcelo Alvarenga; Amilcar C de Matos; Izilda Aparecida Cardinalli; Renée Zon Filippi; Marilia G de Castro; Sueli Suzigan

We report seven cases of renal medullary carcinoma collected from several institutions in Brazil. In spite of a relatively high incidence of sickle cell trait in Brazil, this is a rare tumor. All patients were males between the ages of 8 and 69 years (mean 22 years). From the collected information, the most frequent presenting symptoms were gross hematuria and flank or abdominal pain. The duration of symptoms ranged from 1 week to 5 months. Most of the tumors were poorly circumscribed arising centrally in the renal medulla. Size ranged from 4 to 12 cm (mean 7 cm) and hemorrhage and necrosis were common findings. All seven cases described showed sickled red blood cells in the tissue and six patients were confirmed to have sickle cell trait. All cases disclosed the characteristic reticular pattern consisting of tumor cell aggregates forming spaces of varied size, reminiscent of yolk sac testicular tumors of reticular type. Other findings included microcystic, tubular, trabecular, solid and adenoid-cystic patterns, rhabdoid-like cells and stromal desmoplasia. A peculiar feature was suppurative necrosis typically resembling microabscesses within epithelial aggregates. The medullary carcinoma of the 69-year-old patient was associated with a conventional clear cell carcinoma. To our knowledge, this association has not been previously reported and the patient is the oldest in the literature. The survival after diagnosis or admission ranged from 4 days to 9 months. The 8-year-old African–Brazilian patient with a circumscribed mass is alive and free of recurrence 8 years after diagnosis. This case raises the question whether a periodic search for renal medullary carcinoma in young patients who have known abnormalities of the hemoglobin gene and hematuria could result in an early diagnosis and a better survival.


Journal of Clinical Pathology | 2011

Expression of CK19 in invasive breast carcinomas of special histological types: implications for the use of one-step nucleic acid amplification

César Augusto Alvarenga; Paula Itagyba Paravidino; Marcelo Alvarenga; Rozany Mucha Dufloth; Madalena Gomes; Luiz Carlos Zeferino; Fernando Schmitt

Background The sentinel lymph node (SLN) is the first lymph node to receive the lymphatic drainage of a primary tumour; based on the knowledge that CK19 is positive in more than 95% of breast carcinomas, a molecular method for intraoperative diagnosis of SLN metastases (the one-step nucleic acid amplification (OSNA) assay) was developed. Aims To evaluate CK19 immunoreactivity in a series of special histological types of breast carcinoma in order to verify whether the OSNA assay can be used in all breast cancer cases independently of the histological type. Methods 116 samples of invasive breast carcinomas of special type were investigated for CK19 immunoreactivity in tissue microarrays (TMA); negative cases were evaluated in the entire tissue tumour tissue. Results Of the 116 cases, 88.9% were positive CK19. Micropapillary and apocrine carcinomas were all positive for CK19 in TMAs. The tubular (93%), mucinous (86%), medullary typical and atypical (84%), mixed carcinomas (83%) increased the rate of positivity for this marker to 100% after repeating the immunostain in whole tissue of negative TMA cases, because the expression of those cases was focal. Conclusion Most breast cancer cases were positive for CK19, independent of the histological type; therefore the OSNA assay can be used in all breast cancer cases with a potential low rate of false negative for CK19 detection of micrometastasis. There is an important variation between the positivity assessed on TMAs and the entire tissue; these findings can be clinically relevant because in some cases CK19 is evaluated on core-needle biopsy prior to surgery.


Applied Immunohistochemistry & Molecular Morphology | 2004

Comparison of immunoexpression of 2 antibodies for estrogen receptors (1D5 and 6F11) in breast carcinomas using different antigen retrieval and detection methods.

José Vassallo; Glauce Aparecida Pinto; Marcelo Alvarenga; Luiz Carlos Zeferino; Cristiano Aparecido Chagas; Konradin Metze

The importance of in situ immunodetection of hormone receptors for therapy planning and prognostic evaluation in patients with breast carcinoma is well established. Sensitive detection methods are of utmost importance, especially in poorly fixed tissues, which are not uncommon in routine pathologic practice. The purpose of the present study is to compare immunoexpression of estrogen receptors in 20 cases of invasive ductal carcinoma using two antibodies, 1D5 and 6F11, and to verify the effect of different antigen retrieval solutions and detection systems. Immunoperoxidase was performed on paraffin sections using 1D5 and 6F11 as primary antibodies. Heat-induced antigen retrieval was performed using citrate buffer (pH 6.0) or Tris-EDTA buffer (pH 8.9). Detection was achieved using the following systems: EnVision, EnVision Plus, and labeled streptavidin-biotin peroxidase complex. Reaction was semiquantified from 0 to 4. There were no differences between the two markers, 1D5 and 6F11, except when 6F11 was used with EnVision and citrate buffer, in which case weaker reactivity was observed. Only in this combination (6F11/EnVision) was EDTA buffer significantly better than citrate. Labeled streptavidin-biotin peroxidase complex presented the best results, followed by EnVision Plus.


The Journal of Urology | 1976

Malacoplakia of the Prostate Confused with Clear Cell Carcinoma

Augusto Afonso Ferreira; Marcelo Alvarenga

Primary malacoplakia of the prostate is a rare benign disease, which is frequently mistaken for carcinoma and granulomatous prostatis. The surgical and clinical course of a patient with obstructive hypertrophy of the prostate is reviewed after an initial incorrect diagnosis of clear cell carcinoma. Experience in defining the lesion during the transurethral resection is presented. The pathogenesis, morphological structure and unique microscopic appearance of malacoplakia, characterized by large mononuclear cells associated with small laminated concretions, are described and illustrated.


Journal of Clinical Pathology | 2012

Reappraisal of immunohistochemical profiling of special histological types of breast carcinomas: a study of 121 cases of eight different subtypes

César Augusto Alvarenga; Paula Itagyba Paravidino; Marcelo Alvarenga; Madalena Gomes; Rozany Mucha Dufloth; Luiz Carlos Zeferino; José Vassallo; Fernando Schmitt

Histological special types (HST) account for about 25% of breast cancers, and correspond to at least 17 pathological entities. However, their molecular characteristics remain to be determined. The purpose of the present study is to apply the recently used immunohistochemical profiling of HST breast carcinomas (BC), as a surrogate for the molecular subtyping, what could be relevant for therapeutic purposes. One hundred and twenty-one cases were included. Immunohistochemical study was performed on paraffin sections, including markers for oestrogen, progesterone and androgen receptors, keratin 5, HER2/neu, epithelial growth factor receptor, p63 protein, P-cadherin, and Ki-67. Tubular (16 cases), mucinous (27) and papillary (9) types were all categorised as luminal-like A and B. The medullary (21) and metaplastic (10) types corresponded largely to the basal-like tumours (85.7% and 90%, respectively). Cases of the micropapillary type (8) were luminal A (3/8), luminal B (4/8) and HER2 overexpressing (1/8), whereas the apocrine carcinomas (24) presented a heterogeneous profile. The proliferation rate (Ki-67) varied among the types, being the medullary carcinoma subtype with higher proliferation. Comparing the current data with those based on molecular studies, there was good agreement in the classification of the tubular, mucinous and papillary types. Only a partial concordance was achieved for the other types, which may be due to sampling, and to the relatively low frequency of such cases. The present work supports the clinical usage of immunohistochemistry as a surrogate to molecular classification of special types of BC.


BMC Cancer | 2009

Immunostaining with D2–40 improves evaluation of lymphovascular invasion, but may not predict sentinel lymph node status in early breast cancer

Anna Valéria de Britto; André Almeida Schenka; Natália G Moraes-Schenka; Marcelo Alvarenga; Julia Yoriko Shinzato; José Vassallo; Laura Sterian Ward

BackgroundSentinel lymph node (SLN) biopsy is a widely used diagnostic procedure in the management of early breast cancer. When SLN is free of metastasis, complete axillary dissection may be skipped for staging in clinically N0 patients, allowing a more conservative procedure. Histological tumor features that could reliably predict SLN status have not yet been established. Since the degree of tumor lymphangiogenesis and vascularization may theoretically be related to the risk of lymph node metastasis, we sought to evaluate the relationship between lymph vessel invasion (LVI), lymphatic microvascular density (LVD), microvascular density (MVD) and VEGF-A expression, with SLN status and other known adverse clinical risk factors.MethodsProtein expression of D2–40, CD34, and VEGF-A was assessed by immunohistochemistry on paraffin-embedded sections of primary breast cancer specimens from 92 patients submitted to SLN investigation. The presence of LVI, the highest number of micro vessels stained for D2–40 and CD34, and the protein expression of VEGF-A were compared to SLN status, clinicopathological features and risk groups.ResultsLVI was detected in higher ratios by immunostaining with D2–40 (p < 0.0001), what would have changed the risk category from low to intermediate in four cases (4.3%). There was no association between LVI and other angiogenic parameters determined by immunohistochemistry with SLN macrometastases, clinical features or risk categories.ConclusionAssessment of LVI in breast carcinoma may be significantly increased by immunostaining with D2–40, but the clinical relevance of altering the risk category using this parameter may not be advocated according to our results, neither can the use of LVI and LVD as predictors of SLN macrometastasis in early breast cancer.


Journal of Ultrasound in Medicine | 2006

Detection of Ovarian Sertoli-Leydig Cell Tumors Exclusively by Color Doppler Sonography

Cleide Mara Mazzotti de Oliveira Franzin; Maria Lúcia Kraft; Daniel Faundes; Luiz Carlos Zeferino; Marcelo Alvarenga; Emílio Francisco Marussi

ertoli-Leydig cell tumors account for less than 0.5% of all ovarian cancers. Here we report the case of a 64-year-old patient who had previously undergone left oophorectomy. She underwent a pelvic scan because of lower abdominal pain. Transvaginal sonography showed a right ovary with normal gray scale images. Color Doppler sonography showed intense blood flow inside the gonad, with a low resistive index. After laparoscopic removal of this ovary, histologic examination revealed an intermediately differentiated Sertoli-Leydig cell tumor. Our findings suggest that intensely vascularized ovaries in postmenopausal patients should be closely followed, and histologic evaluation should be considered if these characteristics persist, even in normal-sized gonads.


Sao Paulo Medical Journal | 2012

Paraganglioma of seminal vesicle and chromophobe renal cell carcinoma: a case report and literature review

César Augusto Alvarenga; José Manuel Lopes; João Vinagre; Paula Itagyba Paravidino; Marcelo Alvarenga; Adilson Prando; Lísias Nogueira Castilho; Paula Soares; Athanase Billis

CONTEXT Extra-adrenal paragangliomas are rare tumors that have been reported in many locations, including the kidney, urethra, urinary bladder, prostate, spermatic cord, gallbladder, uterus and vagina. CASE REPORT This report describes, for the first time to the best of our knowledge, a primary paraganglioma of the seminal vesicle occurring in a 61-year-old male. The patient presented persistent arterial hypertension and a previous diagnosis of chromophobe renal cell carcinoma. It was hypothesized that the seminal vesicle tumor could be a metastasis from the chromophobe renal cell carcinoma. Immunohistochemical characterization revealed expression of synaptophysin and chromogranin in tumor cell nests and peripheral S100 protein expression in sustentacular cells. Succinate dehydrogenase A and B-related (SDHA and SDHB) expression was present in both tumors. CONCLUSIONS No genetic alterations to the VHL and SDHB genes were detected in either the tumor tissue or tissues adjacent to the tumor, which led us to rule out a hereditary syndrome that could explain the association between paraganglioma and chromophobe renal cell carcinoma in a patient with arterial hypertension.

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José Vassallo

State University of Campinas

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Luiz Carlos Zeferino

State University of Campinas

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César Cabello

State University of Campinas

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