Interpretation of the post-surgical Somatostatin Receptor Scintigram of a Primary Neuroendocrine Tumor of the Thymus: a case report and literature review

A case of a thymic neuroendocrine tumor and the interpretation problems in a post-surgical Somatostatin Receptor Scintigraphy are presented. In a 53-year-old man with superior vena cava obstruction syndrome an atypical carcinoid of the thymus (neuroendocrine carcinoma of intermediate grade 2), was found at surgery. During his first year of follow-up a Somatostatin Receptor Scintigraphy was recommended. An area of abnormal concentration of the radiopharmaceutical was revealed in the mediastinum at this time. A thorough understanding of the mechanisms of the radiopharmaceutical uptake and of the various clinical settings in which uptake can occur are essential for a proper evaluation of the scintigraphic findings and result in the optimal use of this valuable modality. The literature review provides an overview of this rare type of tumor and insight into the clinical significance of Somatostatin Receptor Scintigraphy

Relationship of cell proliferation (Ki-67) to (99m)Tc-(V)DMSA uptake in breast cancer

INTRODUCTION: The aim of the present study was to identify the relationships between the uptake of radiotracers – namely pentavalent dimercaptosuccinic acid [(V)DMSA] and sestamibi (MIBI) – and the following parameters in primary breast cancer: steroid receptor concentrations (i.e. estrogen receptor [ER] and progesterone receptor [PR]), Ki-67 expression, tumor size, tumor grade, age, and levels of expression of p53 and c-erbB-2. In addition, by multivariate regression analysis, we further isolated those factors with independent associations with (V)DMSA and/or MIBI uptake in primary breast cancer. METHODS: Thirty-four patients with histologically confirmed breast carcinoma underwent preoperative scintimammography with technetium-99m ((99m)Tc)-(V)DMSA and/or (99m)Tc-MIBI in consecutive sessions 10 and 60 min after administration of 925–1110 MBq of each radiotracer. The tumor-to-background ratio was calculated and correlated with the presence of ER, PR, Ki-67, tumor size, tumor grade, p53, and c-erbB-2. ER, PR, p53, and c-erbB-2 were determined immunohistochemically. The analysis included tumor-to-background ratio of (V)DMSA and MIBI uptake as dependent and all of the other parameters as independent variables. RESULTS: Correlation was positive between Ki-67 and (V)DMSA (r = 0.37 at 10 min, P = 0.038; r = 0.42 at 60 min, P = 0.018) and inverse between PR and (V)DMSA uptake (r = -0.46 at 10 min, P = 0.010; r = -0.51 at 60 min, P = 0.003). Multivariate regression analysis demonstrated a positive correlation between Ki-67 and (V)DMSA at 60 min (P = 0.045). Ki-67 was not significantly correlated with MIBI uptake, whereas tumor size was positively correlated with MIBI uptake at 60 min both in univariate (r = 0.45, P = 0.027) and multivariate analysis (P = 0.024). Negative correlations were observed between (V)DMSA uptake and ER, as well as between ER/PR and MIBI uptake, but these were not significant. CONCLUSION: Ki-67 appears to represent the major independent factor affecting (V)DMSA uptake in breast cancer. Tumor size was the only independent parameter influencing MIBI uptake in breast cancer. (V)DMSA appears to have an advantage over MIBI in that it can be used to visualize tumors with intense proliferative activity, and thus it can identify those tumors that are more aggressive

Imaging in situ breast carcinoma (with or without an invasive component) with technetium-99m pentavalent dimercaptosuccinic acid and technetium-99m 2-methoxy isobutyl isonitrile scintimammography

INTRODUCTION: The aim of the study was to retrospectively define specific features of the technetium-99m pentavalent dimercaptosuccinic acid ((99m)Tc-(V)DMSA) and technetium-99m 2-methoxy isobutyl isonitrile ((99m)Tc-Sestamibi [(99m)Tc-MIBI]) distribution in ductal breast carcinoma in situ and lobular breast carcinoma in situ (DCIS/LCIS), in relation to mammographic, histological and immunohistochemical parameters. MATERIALS AND METHODS: One hundred and two patients with suspicious palpation or mammographic findings were submitted preoperatively to scintimammography (a total of 72 patients with (99m)Tc-(V)DMSA and a total of 75 patients with (99m)Tc-Sestamibi, 45 patients receiving both radiotracers). Images were acquired at 10 min and 60 min, and were evaluated for a pattern of diffuse radiotracer accumulation. The tumor-to-background ratios were correlated (T-pair test) with mammographic, histological and immunohistochemical characteristics. RESULTS: Histology confirmed malignancy in 46/102 patients: 20/46 patients had DCIS/LCIS, with or without coexistent invasive lesions, and 26/46 patients had isolated invasive carcinomas. Diffuse (99m)Tc-(V)DMSA accumulation was noticed in 18/19 cases and (99m)Tc-Sestamibi in 6/13 DCIS/LCIS cases. Epithelial hyperplasia demonstrated a similar accumulation pattern. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value for each tracer were calculated. Solely for (99m)Tc-(V)DMSA, the tumor-to-background ratio was significantly higher at 60 min than at 10 min and the diffuse uptake was significantly associated with suspicious microcalcifications, with the cell proliferation index ≥ 40% and with c-erbB-2 ≥ 10%. CONCLUSION: (99m)Tc-(V)DMSA showed high sensitivity and (99m)Tc-Sestamibi showed high specificity in detecting in situ breast carcinoma ((99m)Tc-(V)DMSA especially in cases with increased cell proliferation), and these radiotracers could provide clinicians with preoperative information not always obtainable by mammography

Atrial natriuretic peptide levels during and after acute cardiac tamponade in dogs

AbstractThe ability of the atrial wall to secrete atria) natriuretic peptide was studied in eight dogs during 2 h of cardiac tamponade and for 2 h after decompression of the pericardium. Cardiac tamponade was induced by instillation of 5% dextrose in water into the pericardial cavity until aortic systolic pressure was reduced by 30% to 35%. Heart rate, cardiac output and atrial, pericardial and aortic pressures were measured at 60 and 120 min of tamponade and at 5, 30, 60, 90 and 120 min after decompression. Blood samples were withdrawn at the same time for the determination of atrial natriuretic peptide and aldosterone levels.Aortic pressure decreased significantly during tamponade and increased after decompression to near control levels. Right and left atrial pressures as well as intrapericardial pressure increased significantly during tamponade and returned to control levels after decompression. The effective transmural pressure, which was reduced during tamponade, was increased significantly at 5 min after decompression. Cardiac output was significantly reduced during tamponade and returned to pretamponade levels after decompression. Over the total experimental period, no significant changes in the levels of atrial natriuretic peptide were observed, whereas aldosterone increased significantly.It is concluded that the increased atrial pressure observed during cardiac tamponade did not stimulate the secretion of atrial natriuretic peptide. Furthermore, atrial distension observed immediately after decompression was not sufficient or of long enough duration to induce measurable increases in atrial natriuretic peptide levels. Finally, the secondary hyperaldosteronism did not activate atrial natriuretic peptide secretion either during cardiac tamponade or after decompression

Imaging breast carcinoma (with or without an invasive component) with technetium-99m pentavalent dimercaptosuccinic acid and technetium-99m 2-methoxy isobutyl isonitrile scintimammography-3

<p><b>Copyright information:</b></p><p>Taken from "Imaging breast carcinoma (with or without an invasive component) with technetium-99m pentavalent dimercaptosuccinic acid and technetium-99m 2-methoxy isobutyl isonitrile scintimammography"</p><p>Breast Cancer Research 2004;7(1):R33-R45.</p><p>Published online 8 Nov 2004</p><p>PMCID:PMC1064097.</p><p>Copyright © 2004 Papantoniou et al., licensee BioMed Central Ltd.</p>. Scintimammography, left lateral projection: Tc-(V)DMSA at 10 min and 60 min (i-ii). Diffuse semi-lunar accumulation (arrow) extending behind the nipple, more prominent in the late image. Tc-Sestamibi scan was not performed in this patient

Correlation of progesterone receptor (PR) with log transformed tumor-to-background ratios (T/B) of pentavalent dimercaptosuccinic acid (V)DMSA uptake at 10 min and 60 min, and sestamibi (MIBI) uptake at 10 min and 60 min

<p><b>Copyright information:</b></p><p>Taken from "Relationship of cell proliferation (Ki-67) to Tc-(V)DMSA uptake in breast cancer"</p><p>Breast Cancer Research 2003;6(2):R56-R62.</p><p>Published online 11 Dec 2003</p><p>PMCID:PMC400650.</p><p>Copyright © 2004 Papantoniou et al., licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.</p> CI, confidence interval