Carlos W.M. Bedrossian

Amiodarone pulmonary toxicity: Cytopathology, ultrastructure, and immunocytochemistry

One hundred ninety cardiac patients were prospectively enrolled in an amiodarone protocol. Over a 10-year period, 16 patients developed new or progressive respiratory symptoms while taking amiodarone. These symptoms included dyspnea associated with abnormal chest radiographs or new or worsening abnormalities on pulmonary function testing. Specimens for microscopic examination were obtained by fiberoptic bronchoscopy with transbronchial lung biopsy (TBB), bronchoalveolar lavage (BAL), open lung biopsy (OLB), or autopsy. Large foamy macrophages with characteristic lamellated cytoplasmic inclusions were noted in all specimens, regardless of other evidence of pulmonary toxicity, suggesting that foamy macrophages represent a routine drug effect. Foamy macrophages were not present in BAL specimens from 53 normal controls and were rarely seen in specimens from 27 patients who had other interstitial lung diseases. When present, the foamy macrophages were less prominent than those seen in specimens from patients receiving amiodarone. Fibrosis was noted in 11 of 16 histological specimens, whereas type II-cell-hyperplasia was observed in 7 of the 16 specimens. Four of the 16 patients with respiratory symptoms died, and their autopsy revealed a combination of foamy macrophages with fibrosis and type II cell hyperplasia reflective of amiodarone pulmonary toxicity. Hyperplastic type II cells were not found in the absence of fibrosis. Immunocytochemistry allowed differentiation between foamy macrophages and type II cells and represents a useful tool for future investigations of the pathogenesis of amiodarone-induced pulmonary disease.

Guidelines for cytopathologic diagnosis of epithelioid and mixed type malignant mesothelioma. Complementary statement from the International Mesothelioma Interest Group, also endorsed by the International Academy of Cytology and the Papanicolaou Society of Cytopathology.

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma (MM). Cytopathologists involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC), who have an interest in the field contributed to this update. Reference material includes peer-reviewed publications and textbooks. This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists, who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in cape town. During the previous IMIG biennial meetings, thorough discussions have resulted in published guidelines for the pathologic diagnosis of MM. However, previous recommendations have stated that the diagnosis of MM should be based on histological material only.[12] Accumulating evidence now indicates that the cytological diagnosis of MM supported by ancillary techniques is as reliable as that based on histopathology, although the sensitivity with cytology may be somewhat lower.[345] Recognizing that noninvasive diagnostic modalities benefit both the patient and the health system, future recommendations should include cytology as an accepted method for the diagnosis of this malignancy.[67] The article describes the consensus of opinions of the authors on how cytology together with ancillary testing can be used to establish a reliable diagnosis of MM.

Heparanase and basic fibroblast growth factor are co-expressed in malignant mesothelioma.

Heparanase is an endoglycosidase that degrades heparan sulfate (HS) in the extracellular matrix (ECM) and cell surfaces, and fulfills a significant role in cancer metastasis and angiogenesis. We evaluated the expression of heparanase and its possible association with the expression of angiogenic molecules in malignant mesothelioma (MM), and analyzed whether expression of these proteins is site-related (pleural vs peritoneal MM, solid lesions vs effusions). Sections from 80 MM (56 biopsies, 24 effusions) were analyzed for heparanase protein expression using immunohistochemistry (IHC). Sixty MM were of pleural origin, and 20 were peritoneal. Effusion specimens consisted of 6 peritoneal and 18 pleural effusions, while biopsies consisted of 14 peritoneal and 42 pleural lesions. Fifty-four specimens were additionally evaluated for expression of basic fibroblast growth factor (bFGF), interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) proteins using IHC. Microvessel density (MVD) was studied in 28 biopsies using an anti-CD31 antibody. mRNA expression of heparanase (HPSE-1), VEGF and the VEGF receptor KDR was analyzed in 23 effusions using RT-PCR. Heparanase protein expression was seen in 69/80 (86%) tumors. Of these, 35 showed combined membrane and cytoplasmic expression, 30 cytoplasmic expression, and four exclusively membrane expression. Both total (P= 0.001) and cytoplasmic (P = 0.002) expression was significantly higher in solid tumors compared to effusions. Protein expression of VEGF, IL-8 and bFGF was seen in 21/54 (39%), 22/54 (41%) and 44/54 (81%) specimens, respectively. Protein expression of bFGF was significantly higher in solid tumors (P 0.001) and correlated with heparanase expression (P = 0.005). HPSE-1 and VEGF mRNA expression was detected in all 23 effusions using RT-PCR, while KDR mRNA was found in 12/23 MM. KDR mRNA expression correlated with that of both HPSE-1 (P = 0.005) and VEGF (P = 0.001). Our results document frequent expression of heparanase in MM, in agreement with the biological aggressiveness of this tumor. The co-expression of heparanase with bFGF is in agreement with the role of the former in releasing bFGF from the ECM. The concomitant reduction in protein expression of both molecules in effusions as compared to solid tumors, supports the hypothesis of a reduced need for pro-angiogenic stimuli in effusions, and may aid in defining tumor progression in this setting.

Thyroid plasmacytoma mimicking medullary carcinoma: A potential pitfall in aspiration cytology

Extramedullary plasmacytoma (EMP), a malignant neoplasm of the soft tissues composed of plasma cells, may occur either as a solitary plasma‐cell tumor (primary EMP) or as a manifestation of multiple myeloma (secondary EMP). We report on the aspiration cytology findings of an intriguing case of EMP of the thyroid that was initially misinterpreted as medullary carcinoma on clinical and cytologic examination. A major contributing cause for the cytologic misinterpretation was the presence of amyloid in the aspirate and the clinical impression of a “thyroid mass.” Based on this experience, we suggest that EMP should be considered in the differential diagnosis of a neck mass that yields discohesive cells associated with amyloid/amyloid‐like material. Clinical correlation and immunocytochemistry are crucial in avoiding pitfalls in this situation. Diagn. Cytopathol. 2000;23:354–358.

Cadherin Expression in Ovarian Carcinoma and Malignant Mesothelioma Cell Effusions

OBJECTIVE To analyze potential differences in cadherin expression between ovarian carcinoma/primary peritoneal carcinoma (OC/PPC) and malignant mesothelioma (MM) at this anatomic site. STUDY DESIGN MM (N=24) and OC/PPC (N= 53) effusions were analyzed for E-cadherin, N-cadherin and P-cadherin protein expression using immunocytochemistry. RESULTS Both MM and OC/PPC cells showed frequent expression of all 3 cadherins. OC/PPC specimens expressed E-cadherin and N-cadherin in 52 of 53 cases and P-cadherin in 51 of 53 cases. MM effusions expressed E-cadherin, N-cadherin and P-cadherin in 22 of 24, 21 of24 and 23 of24 cases, respectively. The differences in the percentage of cadherin-positive cells was weakly significant for P-cadherin (higher expression in MM, p = 0.04), but E-cadherin and N-cadherin expression was comparable (p > 0.05). CONCLUSION MM and OC/PPC coexpress different cadherin family members. P-cadherin, E-cadherin and N-cadherin are not useful for differentiation between OC/PPC and MM in effusions.

CD147 immunohistochemistry discriminates between reactive mesothelial cells and malignant mesothelioma.

Malignant mesothelioma (MM) is a rare form of cancer. Its histopathological diagnosis is very difficult, as it exhibits a number of different appearances that can be misinterpreted as metastatic invasion or atypical hyperplasia. Thus, there is an urgent need to identify adequate markers to distinguish between benign and malignant cells, allowing the implementation of appropriate therapies and, possibly, specific directed therapies. MM, like other tumors, show an increase in glucose uptake, due to high rates of glycolysis, inducing an intracellular overload of acids. In this context, monocarboxylate transporters (MCTs) emerge as important players, by mediating the transmembranar co‐transport of lactate with a proton, thereby, regulating pH and allowing continuous glycolysis. Importantly, proper MCT expression and activity depend on its co‐expression with a chaperone, CD147, which is associated with poor prognosis in cancer. Twenty‐two samples including reactive mesothelial cells, MM, and atypical mesothelial hyperplasias were evaluated for immunoexpression of MCT1, MCT4, and CD147. Expression of these proteins was compared with GLUT1 as a new promising marker for MM. Although MCT isoforms were not differentially expressed in the two types of cytological specimens, CD147, as GLUT1, was almost exclusively expressed in MM. Both MCT1 and MCT4 are not able to discriminate between mesothelial reactive cells and mesothelial malignant cells, while CD147 was able to distinguish these two proliferations. If confirmed, besides being a good marker for identification of MM, CD147 may also be a target for therapeutical strategies in this rare type of tumor. Diagn. Cytopathol. 2012;40:478–483.

Guidelines for the Cytopathologic Diagnosis of Epithelioid and Mixed-Type Malignant Mesothelioma

Objective: To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma. Data Sources: Cytopathologists with an interest in the field involved in the International Mesothelioma Interest Group (IMIG) and the International Academy of Cytology (IAC) contributed to this update. Reference material includes peer-reviewed publications and textbooks. Rationale: This article is the result of discussions during and after the IMIG 2012 conference in Boston, followed by thorough discussions during the 2013 IAC meeting in Paris. Additional contributions have been obtained from cytopathologists and scientists who could not attend these meetings, with final discussions and input during the IMIG 2014 conference in Cape Town.

Guidelines for the cytopathologic diagnosis of epithelioid and mixed-type malignant mesothelioma: Complementary Statement from the International Mesothelioma Interest Group, Also Endorsed by the International Academy of Cytology and the Papanicolaou Socie: IMIG Guidelines for the Pathologic Diagnosis of MM

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma.

The value of monoclonal antibody B72.3 for the diagnosis of breast carcinoma: Experience with the first commercially available source

One hundred cases of invasive breast carcinoma were studied using the commercially available monoclonal antibody Anti-Human Tumor-Associated Glycoprotein-72 (MAb B72.3, Biomedical Technologies Inc, Stoughton, MA) prediluted at 8.5 micrograms/mL. Forty-three cases displayed positive reactivity with this antibody. Intensity and distribution of positive staining varied among the tumor cells. Twenty-two cases had 1% or less reactive cells, while eight cases contained 40% or more positive tumor cells. Apical cell membrane and diffuse cytoplasmic staining were present. In fifteen cases intracytoplasmic lumina and extra-cellular secretory material were highlighted by positive staining. Thirty-five cases had benign breast tissue adjacent to the tumor. Benign ductal and lobular epithelial cells were nonreactive except for two cases in which small foci of apocrine metaplasia were positive. Reactivity with MAb B72.3 was not dependent upon histologic grade, nuclear grade, nodal status, or patient age. Excluding the lower number of positively stained cases, our findings were similar to other MAb B72.3 investigations. The number of positively stained cases and the intensity of the positivity were increased by using MAb B72.3 at 5.0 micrograms/mL with overnight incubation, or by using MAb B72.3 at 40.0 micrograms/mL with 2 hours of incubation. Our findings confirm that MAb B72.3 shows reliable reactivity with breast carcinoma that is sensitive to antibody concentration and incubation time without loss of specificity for tumor cells. Our results are also consistent with the view that MAb B72.3 probably detects epithelial membrane-related antigens in breast carcinoma, as do several other antibodies.

Guidelines for the Cytopathologic Diagnosis of Epithelioid and Mixed-Type Malignant Mesothelioma: a secondary publication.

To provide practical guidelines for the cytopathologic diagnosis of malignant mesothelioma.