Immunocytochemical identification of carcinomas of unknown primary in serous effusions

Metastases from carcinomas of unknown primary site (CUP) in serous effusion are a common clinical problem. Immunocytochemistry was applied as an adjunct to the cytological diagnosis of metastatic carcinomas in serous effusions.Subjects of this study were 118 pleural, 53 peritoneal, and 9 pericardial effusions from 180 patients routinely investigated in the Institute of Cytopathology. Specimens were primarily stained according to Papanicolaou (Pap). The avidin-biotin-complex method (ABC) was secondarily applied for the visualization of immunologic reactions.We have used a panel of six monoclonal antibodies (CK 5/6, CK 7, CK 20, CA 125, TTF-1, and cdx 2) so as to identify the primary tumor site of metastatic carcinoma cells in serous effusions. Applying an algorithm of immunocytochemical marker constellations, we were able to correctly diagnose primary tumor sites in 86 of 101 (85.1%) patients with CUP syndromes. The best result was achieved for the identification of metastatic carcinomas of the ovaries (94.7%) and the lungs (88.1%).We established an algorithm comprising six immunocytochemical markers that enabled a correct diagnosis of primary tumor sites in 85.1%. The panel studied could be useful in diagnostic routine for the identification of primary tumors of unknown origin metastatic to the serous membranes.     

Tumor type and single-cell/mesothelial-like cell pattern of breast carcinoma metastases in pleural and peritoneal effusions

Invasive ductal and lobular breast carcinomas often have different preferred metastasis sites and distinct histomorphologic characteristics. Their metastatic cytomorphologic cell features in body cavity fluids are generally readily recognized, but the single-cell/mesothelial-like pattern and its relationship to the primary tumor type have not been well studied, nor whether metastases have a propensity for certain body cavity sites on the basis of the primary tumor type. To further assess the tumor type and single-cell pattern of breast carcinoma metastases in pleural and peritoneal effusions, we retrospectively studied 853 pleural and peritoneal effusions and correlated the findings with the primary tumor type. When necessary, the single- cell/mesothelial-like pattern was documented immunohistochemically. Metastatic breast carcinomas represented 249 (50.8%) of 490 pleural and 51 (14.0%) of 363 peritoneal effusions. Most metastases in pleural and peritoneal effusions were ductal carcinomas (92.4% and 62.7%, respectively). Lobular carcinoma accounted for only 2 (0.8%) of 249 pleural and 11 (21.6%) of 51 peritoneal effusions. The single-cell/mesothelial-like cell pattern was found in all lobular carcinomas but also in 11 (6.0%) of 184 reviewed ductal carcinomas (nine pleural and two peritoneal). Awareness of these findings and the use of immunohistochemical analyses are necessary for accurately diagnosing metastatic breast carcinoma, especially lobular type.     

Differentiating reactive mesothelial cells from metastatic adenocarcinoma in serous effusions: The utility of immunocytochemical panel in the differential diagnosis

Differentiating reactive mesothelial cells (RMs) from metastatic adenocarcinoma cells (MAC) in serous fluids based on cytomorphologic features alone can be very challenging. Various immunocytochemical (ICC) markers have been used to maximize the diagnostic accuracy, however, cytopathologists still encounter difficulties in effusion cytologic diagnosis. The aim of this study was to evaluate previous and recent ICC stains to identify the most sensitive and specific markers and the best panel for differentiating RM from MAC. Cell block sections from 41 MAC and 43 RM effusions cases were subjected to ICC staining for MOC‐31, BerEp4, carcinoembryonic antigen (CEA), calretinin, HBME‐1, CK5/6, and D2‐40. For the MAC cases, the sensitivity of BerEp4, MOC‐31, and CEA was 82.9, 92.6, and 17%, respectively, and the specificity was 95.3, 93, and 100%, respectively. For the RM cases, the sensitivity of calretinin, CK5/6, D2‐40, and HBME‐1 was 95.3, 27.9, 58.1, and 93%, respectively, and the specificity was 70.7, 73.1, 75.6, and 82.9%, respectively. The results show that BerEp4 and MOC‐31 are highly sensitive and specific for detecting MAC, whereas calretinin and HBME1 are highly sensitive but only modestly specific for detecting RM cases (P < 0.05). Forced entry logistic regression revealed that using MOC‐31, BerEp4, HBME‐1, and calretinin, is an excellent panel for making correct diagnosis with 97.6% sensitivity in detecting MAC and 90.7% specificity in detecting RM. We conclude that adding a panel of MOC‐31, BerEp4, calretinin, and HBME‐1 immunostains to routine cytomorphologic features can greatly enhance the diagnostic accuracy of serous effusions. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Diagnostic usefulness of EMA, IMP3, and GLUT-1 for the immunocytochemical distinction of malignant cells from reactive mesothelial cells in effusion cytology using cytospin preparations

To differentiate reactive mesothelial cells (RMs) from metastatic carcinoma and malignant mesothelioma (MM) in effusion cytology is crucial for the cytologic diagnosis and the management of the patients. In the present study, the immunocytochemical staining profile of the epithelial membrane antigen (EMA), the insulin-like growth factor-II mRNA-binding protein 3 (IMP3), and the glucose transporter-1 (GLUT-1) was examined to distinguish RMs from malignant cells. A total of 171 pleural (n = 87) and peritoneal (n = 84) effusion specimens, including 50 benign effusions with RMs, 11 MM effusions, and 110 metastatic malignant effusions, were evaluated for immunocytochemistry. EMA, IMP3, monoclonal GLUT-1, and polyclonal GLUT-1 immunoreactivity were observed in 26.0%, 6.0%, 20.0%, and 18.0% of RMs, respectively. In contrast to RMs, the immunoreactivity in MM was 100%, 36.4%, 100%, and 90.9%; adenocarcinoma (AC) was 100%, 80.8%, 81.7%, and 72.1%; squamous-cell carcinoma was 83.3%, 83.3%, 83.3%, and 66.7%. EMA, IMP3, mGLUT-1, and pGLUT-1 expressions were observed in 98.4%, 65.6%, 88.5%, and 75.4% in the pleural effusion with malignant cells, and 100%, 88.3%, 78.3%, and 71.7% in ascites containing malignant cells, respectively. The findings of the present study indicate that the immunocytochemical staining for EMA, IMP3, and GLUT-1 is a useful diagnostic tool for distinguishing effusions containing malignant cells from those that contain benign cells, and in particular, we suggest that the combination of mGLUT-1 and EMA, and IMP3 and EMA are extremely useful in pleural effusion and in ascites, respectively.     

Contribution of immunocytochemical stainings for galectin‐3, CD44, and HBME1 to fine‐needle aspiration cytology diagnosis of papillary thyroid carcinoma

In cytology practice some papillary thyroid carcinoma (PTC) cases have indeterminate diagnoses and overlapping cytological features with benign lesions. This study was undertaken to find out if immunocytochemistry using Galectin‐3, CD‐44 and HBME‐1 could be of help in such situations. Forty‐six cases consisting of 22 malignancy (PTC) cases, 7 suspicious of (S/O) PTC, 1 follicular neoplasm, 5 follicular lesion of undetermined significance (FLUS), and 11 benign (colloid goiter) cases diagnosed by FNA were included in this study. Staining reactions were graded in a sliding scale of –, 1+, 2+, 3+, and 4+. In an assessment of 100 cells, each cell with weak, and moderate to strong positive reaction were assigned a score of 1 and 4, respectively. Staining reaction of ≥+2 and scores >100 were considered positive. Frequency of cases with ≥+2 reaction, and scores >100 for each of Galectin‐3, CD‐44, and HBME‐1 were significantly higher in PTC or combined PTC and S/O PTC cases as compared with FLUS and benign cases taken together (P = 0.01744 to 0.00000). When the cases were compared according to histological malignant and benign diagnoses, the difference was also significant in respect of ≥+2 reaction, and scores >100 for Galectin‐3 and CD44 (P = 0.04923 to 0.00947); however, there was no significant difference, when these parameters for HBME1 were compared. Galectin 3, CD 44, and to some extent HBME 1 are useful immunocytochemical parameters with potential to support FNAC diagnosis of PTC, especially in situations with difficult differential diagnoses. Diagn. Cytopathol. 2014;42:498–505. © 2013 Wiley Periodicals, Inc.     

Evidence for cell-specific changes with age in expression of oestrogen receptor (ER) alpha and beta in bone fractures from men and women

Oestrogen is recognized as important for maintaining bone mass in men and women. Oestrogen receptor (ER) alpha and the recently described ER-beta are both expressed in bone cells, but have different affinities for oestrogen agonists and plant oestrogens, which could be important in developing treatments for bone loss in both men and women. It is unclear, however, which isoform predominates in bone; cell type and age may influence their relative expression. The present study has compared ER-alpha and ER-beta expression in serial sections of human fracture callus from males (n = 19, age range 5-72 years) and females (n = 15, age range 3-86 years) by indirect immunoperoxidase. Fracture callus was used as it can be readily obtained from individuals over a wide age range and contains a variety of bone cells. Antibody specificity was confirmed by western blotting and comparison of immunoreactivity in sections of breast tumour and benign prostate hyperplasia. No gender difference in ER expression was found in bone from individuals less than 40 years old. Proliferative chondrocytes were positive for both isoforms, but few larger hypertrophic cells were immunoreactive. ER-alpha and ER-beta were co-expressed in osteoclasts, suggesting that oestrogen may act directly on these cells. Osteoblasts, osteocytes, and mesenchymal cells also expressed both isoforms. In women over 40 years of age, however, relatively fewer biopsies contained osteocytes positive for ER-alpha and ER-beta. Likewise, the proportions of osteoblasts and mesenchymal cells expressing ER-beta were reduced but ER-alpha remained unaffected. In contrast, in men over 40 years, only the proportion of biopsies containing ER-beta-positive mesenchymal cells was lower. In these older men and women, ER-alpha and ER-beta expression was retained by the small proliferative chondrocytes. These results demonstrate that gender, age, and cell type are important determinants of ER isoform expression in skeletal cells.