Malignancy mimic: Suspicious mammographic and sonographic findings post-vacuum-assisted excision biopsy.

Vacuum-assisted excision biopsy (VAEB) provides a safe alternative to surgical excision for selected (low-risk) B3 breast lesions. We report a case of imaging findings that mimicked malignancy in a patient one year post-VAEB. Awareness of this entity is important to prevent misdiagnosis and unnecessary surgical excision.

Expression of Cathepsins B, D, and G in Microcystic Lymphatic Malformation.

Background: This study investigated the expression and localization of cathepsins B, D, and G in relationship to the embryonic stem cell (ESC)-like population we have previously identified in microcystic lymphatic malformation (mLM). Methods and Results: Immunohistochemical staining demonstrated expression of cathepsins B, D, and G in cervicofacial mLM tissue samples from 11 patients. Immunofluorescence staining of two representative mLM samples showed localization of cathepsins B and D to the OCT4+ and the c-MYC+ cells on the endothelium of lesional vessels and the stroma, while cathepsin G was localized to the OCT4+/tryptase+ cells within the stroma. Transcript expression of cathepsins B, D, and G was confirmed using reverse transcription quantitative polymerase chain reaction (RT-qPCR; n = 5). Western blotting (n = 3) performed on the mLM tissue samples revealed protein expression of cathepsins B and D, which were demonstrated to be enzymatically active using enzymatic activity assays. Conclusion: This study demonstrated expression of cathepsins B and D by the ESC-like cells on the endothelium of lesional vessels and the stroma, while cathepsin G was localized to the OCT4+ phenotypic mast cells within the stroma of mLM.

Rare Association between Giant Right Ventricular Myxoma and Right Coronary Artery Tumour Blush with Complicating Pulmonary Tumour Embolism.

Cardiac myxoma is a benign primary cardiac tumour which can present with nonspecific symptoms of right heart failure, syncope, exertional dyspnea, and pulmonary embolism. We describe a case of a right ventricular myxoma complicated with bilateral pulmonary embolism, with an incidental right coronary artery fistula but otherwise normal coronary anatomy on coronary angiogram. This case report emphasizes the importance of performing a transesophageal echo in the setting of pulmonary embolism to search for the origin of thrombus/tumour, and performing a comprehensive assessment is also necessary to rule out coronary artery disease, coronary artery fistula that may also represent a tumour blush.

Expression and Localization of Cathepsins B, D and G in Cancer Stem Cells in Liver Metastasis From Colon Adenocarcinoma.

AIM: We have previously identified and characterized cancer stem cell (CSC) subpopulations in liver metastasis from colon adenocarcinoma (LMCA). In this study we investigated the expression and localization of cathepsins B, D and G, in relation to these CSCs. METHODS: 3,3-Diaminobenzidine (DAB) immunohistochemical (IHC) staining for cathepsins B, D and G was performed on 4µm-thick formalin-fixed paraffin-embedded LMCA sections from nine patients. Immunofluorescence (IF) IHC staining was performed on three representative samples of LMCA from the original cohort of nine patients, to determine the localization of these cathepsins in relation to the CSC subpopulations. NanoString mRNA analysis and Western Blotting (WB) were used to examine the transcript and protein expression of these cathepsins, respectively. Enzyme activity assays were utilized to determine their functional activity. Data acquired from counting of cells staining positively of the cathepsins on the DAB IHC-stained slides and from Nanostring mRNA analysis were subjected to statistical analyses to determine significance. RESULTS: DAB IHC staining demonstrated expression of cathepsins B, D and G within LMCA. IF IHC staining demonstrated the expression of both cathepsin B and cathepsin D by the OCT4- cells within the tumor nests and the OCT4+ CSC subpopulation within the peritumoral stroma. NanoString mRNA analysis showed significantly greater transcript expression of cathepsin B and cathepsin D, compared to cathepsin G. WB confirmed expression of cathepsin B and cathepsin D proteins, while cathepsin G was below detectable levels. Enzyme activity assays showed functional activity of cathepsin B and cathepsin D. CONCLUSION: Our study demonstrated novel finding of the expression of cathepsin B, cathepsin D, and possibly cathepsin G by the putative CSC subpopulations within LMCA.

Characterization of Cancer Stem Cells in Colon Adenocarcinoma Metastasis to the Liver.

BACKGROUND: Fifty percent of colorectal cancer (CRC) patients develop liver metastasis. This study identified and characterized cancer stem cells (CSCs) within colon adenocarcinoma metastasis to the liver (CAML). METHODS: 3,3-Diaminobenzidine immunohistochemical (IHC) staining was performed on nine CAML samples for embryonic stem cell (ESC) markers OCT4, SOX2, NANOG, c-Myc, and KLF4. Immunofluorescence (IF) IHC staining was performed to investigate coexpression of two markers. NanoString mRNA expression analysis and colorimetric in situ hybridization (CISH) were performed on four snap-frozen CAML tissue samples for transcript expression of these ESC markers. Cells stained positively and negatively for each marker by IHC and CISH staining were counted and analyzed. RESULTS: 3,3-Diaminobenzidine IHC staining, and NanoString and CISH mRNA analyses demonstrated the expression of OCT4, SOX2, NANOG, c-Myc, and KLF4 within in all nine CAML samples, except for SOX2 which was below detectable levels on NanoString mRNA analysis. IF IHC staining showed the presence of a SOX2+/NANOG+/KLF4+/c-Myc+/OCT- CSC subpopulation within the tumor nests, and a SOX2+/NANOG+/KLF4+/c-Myc+/OCT4- CSC subpopulation and a SOX2+/NANOG+/KLF4+/c-Myc+/OCT4+ CSC subpopulation within the peritumoral stroma. CONCLUSION: The novel finding of three CSC subpopulations within CAML provides insights into the biology of CRC.