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    Clinical use of an imaging probe in breast cancer surgery.

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    1. Tumori. 2002 May-Jun;88(3):S35-7. Clinical use of an imaging probe in breast cancer surgery. Scafè R, Soluri A, Amanti C, Burgio N, Capoccetti F, David V, Stella S, Scopinaro F. ENEA-CR Casaccia, Rome, Italy. Abstract AIMS: Portable cameras allow easy transfer of the detector, and thus of radioisotope imaging, to the operating room. In this paper we describe our preliminary experience in radionuclide imaging of breast cancer with a 22.8 x 22.8 mm(2) field-of-view minicamera called "Imaging Probe" (IP). METHODS: Breast cancer detection by IP was performed to guide biopsy, in particular open biopsy, or help fine-needle or core-needle positioning when the main guidance method was ultrasonography or digital radiography. 99mTc Sestamibi (MIBI) was injected 1 h before imaging and biopsy to 14 patients with suspected or known breast cancer. Scintigraphic images were acquired before and after biopsy in each patient. The surgeon was allowed to take into account scintigraphic images as well as previously performed mammograms and ultrasonography. RESULTS: High-resolution IP images were able to guide biopsy toward cancer or toward washout zones of cancer which are thought to be chemoresistant in seven patients out of 10. Four patients in whom IP and MIBI were unable to guide biopsy were found not to have cancer. CONCLUSIONS: Our study confirms the ability of IP to guide breast biopsy even when our minicamera has to be handled manually by trained physicians during surgery. PMID: 12365382 [PubMed - indexed for MEDLINE

    Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera

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    Delayed liver single-photon emission computed tomography (SPECT) after (99m)Tc red blood cell (RBC) labelling is helpful in detecting hepatic haemangiomas; however, diagnosis can be difficult when lesions are situated adjacent to structures like the inferior vena cava, the heart or hepatic vessels, where blood activity persists. The aims of this study were to evaluate the usefulness of RBC SPECT and transmission computed tomography (RBC SPECT/CT) performed simultaneously with a hybrid imaging system for correct characterisation of hepatic lesions in patients with suspected haemangioma, and to assess the additional value of fused images compared with SPECT alone. Twelve patients with 24 liver lesions were studied. The acquisitions of both anatomical (CT) and functional (SPECT) data were performed during a single session. SPECT images were first interpreted alone and then re-evaluated after adding the transmission anatomical maps. Image fusion was successful in all patients, with perfect correspondence between SPECT and CT data, allowing the precise anatomical localisation of sites of increased blood pool activity. SPECT/CT had a significant impact on results in four patients (33.3%) with four lesions defined as indeterminate on SPECT images, accurately characterising the hot spot foci located near vascular structures. In conclusion, RBC SPECT/CT imaging using this hybrid SPECT/CT system is feasible and useful in the identification or exclusion of suspected hepatic haemangiomas located near regions with high vascular activity

    In vivo detection of resistance to anthracycline based neoadjuvant chemotherapy in locally advanced and inflammatory breast cancer with technetium-99m sestamibi scintimammography

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    Neoadjuvant chemotherapy (NACT) is the treatment of choice in patients (pts) with locally advanced (LABC) and inflammatory breast cancer (IBC). To evaluate the role of Tc-99m sestamibi imaging in the prediction of response to NACT and in the in vivo functional detection of intrinsic or acquired chemoresistance, 24 female pts with LABC (n=21) or IBC (n=3) were prospectively studied. Tc-99m scintimammography was performed 1-3 days before treatment (first) and 2-5 days after the completion (second) of NACT (epirubicin and cyclophosphamide for LABC and doxorubicin and vinorelbine for IBC). Three planar images (2 lateral prone and one anterior supine, 10 min/each) were obtained 10 min postinjection and a lateral prone image (10 min) of the affected breast (B) was obtained at 4 It. To calculate the tumor to normal B ratio (TBR), 2 identical irregular regions of interest (ROIs) were drawn around the tumor (T) and in adjacent ipsilateral normal B on both early (E) and delayed (D) prone lateral images. The TBR was obtained as the ratio of the mean counts per pixels in the 2 ROIs. Then Tc-99m sestamibi retention index (RI) in the T was determined by dividing the D-TBR by the E-TBR. Afterwards, NACT response was assessed pathologically or clinically in inoperable disease. Scintigraphic sensitivity for correct prediction of T presence after NACT was 81% (17/21), whereas specificity for correct prediction of T absence was 100% (3/3). In LABC, 3 patients had a pathological complete response: first RI was high (>0.56) in all 3, while no T uptake was visible on the second scintigraphy. Eighteen patients did not show a pathological complete response: in 5, both first and second RI were low (less than or equal to0.56); 9 had high first RI but low second; 4 had high first RI and no T detected on the second scan. In IBC, the only patient with a clinical complete response had both first and second RI high, whereas the 2 non-responsive pts had both first and second RI low. These results indicate that Tc-99m sestamibi scintimammography can predict LABC and IBC response to NACT. The scintigraphy protocol, including 2 studies before and after NACT, is useful for detecting intrinsic and acquired chemoresistant BC in vivo, which is important for planning therapy and predicting prognosis

    Somatostatin receptor scintigraphy in metastatic breast cancer patients

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    The purpose of this study was to evaluate the efficacy of somatostatin receptor scintigraphy (SRS) in imaging metastases in patients with advanced breast cancer (BC), and assess the relationship between exposure to chemotherapy and hormonotherapy with overexpression of somatostatin receptor (SS-R) on the breast cancer cell surface. Twelve patients with metastatic breast cancer were intravenously (i.v.) injected with In-111 pentatreotide (120 MBq). Early and later images were obtained with a double-head gamma camera equipped with medium-energy collimators. SPECT was performed when needed. Imaging results were compared with computed tomography and bone scan. Uptake levels were evaluated by site-specific visual analysis. Metastatic breast cancer can be visualized with SRS. Global sensitivity of imaging was 80% and specificity for correct prediction of tumor absence was 100%. Sensitivity was significantly higher for bone and lung metastases. SRS results related to the expression of SS-R on metastatic cell surfaces did not evidence a relationship with the biologic characteristics of the primary BC and drug exposure. In our series, SRS quantitative analysis demonstrated that tumor metastases differ greatly in uptake levels. Fifteen percent of metastatic sites in our series showed strong uptake. Our data support the important specificity of SRS in identifying BC metastases, mostly in cases of bone and lung disease, as well as the role of SRS in predicting responsiveness of metastatic BC cells to treatment with somatostatin analogues (SS), when SS-Rs are overexpressed on cell surfaces. If our results are confirmed in large scale studies, SRS shows the potential to treat selected patients with overexpressed SS-R on their tumoral cells with designed target therapies with SS analogue

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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