Stefano Valentini

IEO - Istituto Europeo di Oncologia, Milano, Lombardy, Italy

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Publications (9)42.6 Total impact

  • Article: Primary vulvar Ewing's sarcoma/primitive neuroectodermal tumor in a post-menopausal woman: a case report.
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    ABSTRACT: Ewing's sarcomas/peripheral primitive neuroectodermal tumors (ES/pPNETs) are high-grade malignant neoplasms rarely found outside the skeletal system. Only 12 cases of vulvar ES/pPNET have so far been reported, all involving children or women of child-bearing age. We describe the case of a 52-year-old woman who was admitted to our hospital for the local excision of a 4cm vulvar mass, originally thought to be a Bartholin's gland cyst. It was subsequently found to consist of small round cells positive for anti-CD99 antibody, thus suggesting a diagnosis of ES/pPNET. The demonstration of EWSR1 gene translocations by means of fluorescent in situ hybridization excluded small-cell carcinoma, squamous cell carcinoma of the small type, Merkel cell carcinoma, and lymphoblastic lymphoma. After surgery, the patient received six cycles of polychemotherapy and radiotherapy; she is still alive and well after 1 year of follow-up. Our findings underline the crucial role of molecular biology techniques in the differential diagnosis of small round cell tumors in these unusual locations.
    Pathology - Research and Practice 09/2009; 206(7):476-9. · 1.21 Impact Factor
  • Article: SP4, a novel anti-cyclin D1 rabbit monoclonal antibody, is a highly sensitive probe for identifying mantle cell lymphomas bearing the t(11;14)(q13;q32) translocation.
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    ABSTRACT: Immunohistochemistry is the most widely used approach in the diagnosis of mantle cell lymphoma (MCL). However, its reliability may be hampered by several technical reasons, necessitating the use of alternative techniques such as the identification of the t(11;14)(q13;q32) translocation to characterize such lesions. The authors compared two monoclonal antibodies (DCS-6 and SP4) for assessing cyclin D1 immunoreactivity in a series of 22 MCLs. Their results documented that SP4, a novel rabbit monoclonal antibody, is more effective than the mouse monoclonal antibody DCS-6, one of the most commonly used reagents in daily practice. Although DCS-6 and SP4 were capable of identifying cyclin D1 immunoreactivity in 95.4% and 100% of the cases analyzed, respectively, the prevalence of cyclin D1 immunoreactive neoplastic cells was significantly (P < 0.0001) higher with SP4 (86.6 +/- 13.1%) than with DCS-6 (39.8 +/- 32%). Moreover, the staining intensity was faint in 16 (76.2%) cases and moderate to strong in 5 (23.8%) cases immunostained with DCS- 6, while all the cases showed a moderate to strong immunoreactivity with SP4 (P < 0.0001). According to an arbitrary score based on the percentage of immunoreactive neoplastic cells and staining intensity, only 10 (45.4%) cases were considered high cyclin D1 expressors after staining with DCS-6, whereas all the cases were high expressors with SP4 (P < 0.0001). These data provide evidence that the SP4 monoclonal antibody may be a fast, easy-to-interpret, and reliable surrogate for the detection of the (11;14) translocation by molecular techniques.
    Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 01/2006; 13(4):318-22. · 1.63 Impact Factor
  • Article: The transactivating isoforms of p63 are overexpressed in high-grade follicular lymphomas independent of the occurrence of p63 gene amplification.
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    ABSTRACT: p63 is a p53-related gene mapping to 3q28 that codes for multiple mRNA transcripts with (TA-p63) or without (DeltaN-p63) transactivating effects on genes that promote cell differentiation and apoptosis. We analysed p63 alterations by immunohistochemistry, quantitative real-time RT-PCR and FISH in a series of 45 follicular lymphomas (FL). None of the tumours showed immunoreactivity for the p40 antibody, which recognizes only the truncated isoforms of p63, or DeltaN-p63 mRNA expression. Immunoreactivity for the 4A4 antibody, which recognizes both the transactivating and the truncated p63 isoforms, was found in 5 +/- 5.5%, 6.85 +/- 4.88% and 33.2 +/- 22.31% of grade I, II and III FL cells, respectively (p < 0.0001). Quantitative RT-PCR analysis showed that all cases but one had TA-p63 mRNA levels higher than non-neoplastic lymphocytes, and that TA-p63 mRNA expression correlated significantly (r = 0.9194, p < 0.0001) with the prevalence of p63 immunoreactivity. FISH extra signals for the p63 gene were found in seven (23.3%) of the 30 cases analysed (0/6 grade I, 2/15 grade II and 5/9 grade III; p = 0.01937). Further hybridizations showed a pattern highly suggestive of chromosome 3 polysomy in six cases. One of these cases also bore extra copies of the p63 and bcl-6 genes. Co-localization of p63 and IgH signals was found in one case. No association between the prevalence of p63 immunoreactivity and extra p63 gene signals was detectable when the cases were dichotomized according to a p63 immunoreactivity threshold of 10%. Our data suggest that TA-p63 is overexpressed in high-grade FL, possibly independent of the occurrence of gene abnormalities, and that it may be involved in the highly complex mechanism of regulation of apoptosis of FL cells.
    The Journal of Pathology 07/2005; 206(3):337-45. · 6.32 Impact Factor
  • Article: Predicting the risk for additional axillary metastases in patients with breast carcinoma and positive sentinel lymph node biopsy.
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    ABSTRACT: To assess whether the risk for nonsentinel node metastases may be predicted, thus sparing a subgroup of patients with breast carcinoma and a positive sentinel lymph node (SLN) biopsy completion axillary lymph node dissection (ALND). The SLN is the only involved axillary lymph node in the majority of the patients undergoing ALND for a positive SLN biopsy. A model to predict the status of nonsentinel axillary lymph nodes could help tailor surgical therapy to those patients most likely to benefit from completion ALND. All the axillary sentinel and nonsentinel lymph nodes of 1228 patients were reviewed histologically and reclassified according to the current TNM classification of malignant tumors as bearing isolated tumor cells only, micrometastases, or (macro)metastases. The prevalence of metastases in nonsentinel lymph nodes was correlated to the type of SLN involvement and the size of the metastasis, the number of affected SLNs, and the prospectively collected clinicopathologic variables of the primary tumors. In multivariate analysis, further axillary involvement was significantly associated with the type and size of SLN metastases, the number of affected SLNs, and the occurrence of peritumoral vascular invasion in the primary tumor. A predictive model based on the characteristics most strongly associated with nonsentinel node metastases was able to identify subgroups of patients at significantly different risk for further axillary involvement. Patients with the most favorable combination of predictive factors still have no less than 13% risk for nonsentinel lymph node metastases and should be offered completion ALND outside of clinical trials of SLN biopsy without back-up axillary clearing.
    Annals of Surgery 03/2005; 241(2):319-25. · 7.49 Impact Factor
  • Article: Cyclin D3 immunoreactivity is an independent predictor of survival in laryngeal squamous cell carcinoma.
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    ABSTRACT: To analyze the prevalence and clinical relevance of cyclin D3 abnormalities in laryngeal squamous cell carcinoma (LSCC). Cyclin D3 immunoreactivity was evaluated in 223 formalin-fixed and paraffin-embedded samples of LSCC patients with a mean follow-up of 62.8 +/- 43.2 months. The occurrence of cyclin D3 extra signals was analyzed by fluorescence in situ hybridization in 47 randomly selected cases collected in a tissue microarray. Cyclin D1 immunoreactivity had been previously investigated in 133 cases. Cyclin D3 immunoreactivity and gene extra signals were found in 39.5% and 42.6% of the cases, respectively, and the concordance between immunohistochemical and fluorescence in situ hybridization results was 70.2% (P = 0.0085). Cyclin D3 immunoreactivity was significantly associated with a high risk of death. Multivariate analysis showed that high tumor grade, exophytic/ulcerating tumor type, low performance status, and cyclin D3 immunoreactivity were the only independent predictors of poor overall survival. In the 133 cases analyzed for both cyclin D1 and cyclin D3, patients with cyclin D1+/cyclin D3+ tumors experienced the worst prognosis, patients with cyclin D1-/cyclin D3- exhibited the most prolonged survival, and with cyclin D1-/cyclin D3+ or cyclin D1+/cyclin D3- tumors an intermediate course was associated. Our data suggest that cyclin D3 immunoreactivity, possibly due to the occurrence of gene extra copies, may represent an adjunct in LSCC patients' prognostication and contribute to identify D-type cyclins as potential targets of newly developed therapies.
    Clinical Cancer Research 02/2005; 11(1):242-8. · 7.74 Impact Factor
  • Article: Cyclin D3 immunoreactivity in follicular lymphoma is independent of the t(6;14)(p21.1;q32.3) translocation or cyclin D3 gene amplification and is correlated with histologic grade and Ki-67 labeling index.
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    ABSTRACT: An abnormal expression of cyclin D3, a key regulator of the cell cycle, has been documented in a variety of human malignancies, and the cyclin D3 gene, mapping to 6p21, may be deregulated in plasma cell myeloma and non-Hodgkin's lymphoma as a result of the t(6;14)(p21.1;q32.3) translocation and/or gene amplification. In the current study, we for the first time investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) the prevalence of cyclin D3 abnormalities in follicular lymphomas (FLs), comparing the results with traditional clinicopathologic characteristics, p27 and skp2 immunoreactivity (IR) and Ki-67 labeling index (LI). Cyclin D3, skp2 and Ki-67 IR significantly increased from grade I to grade III FL (p = 0.0003, p = 0.0001 and p < 0.0001, respectively), while p27 IR was significantly (p < 0.0001) more prevalent in low-grade tumors. Cyclin D3 IR was directly correlated with the Ki-67 LI (p < 0.0001) and inversely correlated with p27 IR (p = 0.050). None of the 13 cases analyzed by FISH showed the t(6;14) translocation, but in 2 (15.3%) grade I FLs 3 cyclin D3 signals were detected. Cohybridization with probes specific for the centromeric region and the long arm of the chromosome 6 indicated trisomy in one case and a pattern highly suggestive for the presence of an isochromosome 6p in the other case. Our data suggest that the t(6;14) translocation may be extremely uncommon in FL and that a deregulated expression of cyclin D3, possibly due to epigenetic mechanisms, may be involved in the pathogenesis of high-grade tumors.
    International Journal of Cancer 10/2004; 112(1):71-7. · 5.44 Impact Factor
  • Article: Angiogenesis occurs in hairy cell leukaemia (HCL) and in NOD/SCID mice transplanted with the HCL line Bonna-12.
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    ABSTRACT: Microvessel density (MVD), a surrogate marker for angiogenesis, was evaluated by anti-CD34 and CD105 monoclonal antibodies (Abs), and found to be increased in the bone marrow (BM) of hairy cell leukaemia (HCL) patients and in a preclinical model of non-obese diabetic/severe combined immunodeficient mice transplanted with the HCL line Bonna-12. The anti-CD105 Ab was significantly more sensitive than anti-CD34 Ab in identifying blood vessels. The BM tumour burden significantly decreased in patients treated with interferon-alpha, but the mean value of MVD remained unchanged. These data suggest that angiogenesis may be involved in the pathogenesis of HCL.
    British Journal of Haematology 03/2003; 120(4):695-8. · 4.94 Impact Factor
  • Article: Angiogenesis occurs in hairy cell leukaemia (HCL) and in NOD/SCID mice transplanted with the HCL line Bonna‐12
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    ABSTRACT: Microvessel density (MVD), a surrogate marker for angiogenesis, was evaluated by anti-CD34 and CD105 monoclonal antibodies (Abs), and found to be increased in the bone marrow (BM) of hairy cell leukaemia (HCL) patients and in a preclinical model of non-obese diabetice/severe combined immunodeficient mice transplanted with the HCL line Bonna-12. The anti-CD105 Ab was significantly more sensitive than anti-CD34 Ab in identifying blood vessels. The BM tumour burden significantly decreased in patients treated with interferon-α, but the mean value of MVD remained unchanged. These data suggest that angiogenesis may be involved in the pathogenesis of HCL.
    British Journal of Haematology 02/2003; 120(4):695 - 698. · 4.94 Impact Factor
  • Article: Cell cycle regulators in multiple myeloma: prognostic implications of p53 nuclear accumulation.
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    ABSTRACT: Multiple myeloma (MM) is characterized by a multistep process of tumorigenesis involving genes that control cell cycle progression. The prevalence and clinical implications of p53, p21, HDM-2, p27, and cyclin E immunoreactivity in MM patients, however, have not been fully elucidated. We evaluated the immunoreactivity (IR) for p53, p21, HDM-2, p27, cyclin E, and Ki-67 in bone marrow biopsies from 48 patients. In 34 (70.8%) cases, TP53 gene mutations and HDM-2 gene amplification were analyzed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and Southern blot densitometric analyses in the corresponding bone marrow aspirates. Nineteen (39.6%) biopsy specimens exhibited > or =10% neoplastic cells immunoreactive for p53, 23 (47.9%) for p21, 28 (58.3%) for HDM-2, 29 (60.4%) for cyclin E, and 16 (33.3%) for Ki-67; 23 (47.9%) tumors had > or =50% neoplastic cells immunoreactive for p27. TP53 gene mutations in exons 5 through 8 were detected in 3 (8.8%) cases, whereas none exhibited HDM-2 gene amplification. In the cases bearing a wild-type TP53 gene, no association was found between p53 accumulation and HDM-2 or p21 IR. The same cases had been previously investigated for the presence of the t(11;14) translocation and cyclin D1 IR; interestingly, a significant inverse correlation between cyclin D1 and p27 or cyclin E IR was noted. In addition to clinical stage and Bartl's histologic stage and grade, p53 accumulation was significantly associated with survival, and it maintained its prognostic significance in a multivariate analysis adjusted for age, clinical stage, and relapse. Our data suggest that the immunohistochemical evaluation of p53 IR in bone marrow biopsies may represent an adjunct in MM patient prognostication.
    Human Pathlogy 01/2003; 34(1):41-7. · 2.88 Impact Factor