Changing clinical course of patients with malignant mesothelioma: Implications for FNA cytology and utility of immunocytochemical staining

Abstract

The diagnosis of both local recurrences and distant metastases of mesothelioma can be accomplished by fine-needle aspiration (FNA) biopsy. Although the previous history of mesothelioma provides strong support for recurrent/metastatic mesothelioma, other diagnostic possibilities (particularly adenocarcinoma) may require exclusion via special stains in some cases. In this study, we report on the morphologic findings in 13 cases of mesothelioma which underwent FNA (7 metastatic lesions, 6 local recurrences). In addition, immunohistochemical staining results for 7 cases with available material using antibodies directed against cytokeratin AE 1/3 and two antibodies reported to show consistently positive results in mesothelioma (calretinin and cytokeratin 5/6) are reported and compared to results seen for 10 cases of adenocarcinoma. All cases of mesothelioma and adenocarcinoma showed strong staining with cytokeratin AE 1/3. Three of 7 cases of mesothelioma showed strong staining with calretinin, while only focal staining was detected in 3 additional cases; only one case showed positive staining with cytokeratin 5/6. One of 10 cases of adenocarcinoma showed calretinin positivity; however, at least focal staining with cytokeratin 5/6 was seen in 4 cases. These results suggest that cytokeratin 5/6 is neither a sensitive nor specific stain for the diagnosis of mesothelioma in cytology material. Calretinin appears to be more specific for mesothelioma but showed disappointing sensitivity for this tumor, potentially limiting its diagnostic utility in FNA material.

Diffuse malignant peritoneal mesothelioma

“…Diagnosis can be made by ascitic fluid cytology, CT scan, and laparoscopy. Cytological examination of ascitic fluid removed by paracentesis rarely results in a positive finding [8]. According to the data review of previous case reports and the current case of DMPM [9e12], the sensitivity of ascitic fluid cytology in the diagnosis of malignant mesothelioma was 54% (7/13).…”

Diagnostic usefulness and challenges in the diagnosis of mesothelioma by endoscopic ultrasound guided fine needle aspiration

“…There remains a consensus that, it is impossible to differentiate among the entities like mesothelioma, carcinoma, and melanoma based on morphology with high certainty. 13,14 The role of immunophenotyping or other supplementary techniques such as ultrastructural evaluation is often essential and can be effectively utilized on cytology preparation. [15][16][17][18][19] The exclusion of melanocytic and lymphoproliferative processes may be achieved by examining the cells of interest for a number of antigens via use of S-100 protein, HMB-45, MART-1, CD15, CD30, and CD45 antibodies.…”

Malignant biphasic pleural mesothelioma metastatic to the liver diagnosed by fine-needle aspiration

“…However, the use of multimodality therapy and experimental techniques (including immunotherapy, gene therapy, and photodynamic therapy) is expected to prolong survival, increasing the number of patients presenting with distant metastases. 7 The diagnosis of both local recurrences and distant metastases of pleural mesothelioma can be accomplished by FNA. To our knowledge, cytomorphology of metastatic pleural mesothelioma to the liver in FNA biopsy has not been previously described.…”

“…As more effective treatment modalities are developed and the clinical course of patients with mesothelioma is improved, it is expected that an increased number of patients will present with distant spread of disease. 7 It will become increasingly important to recognize the cytomorphologic features of metastatic pleural mesothelioma on fine-needle aspiration (FNA), the review of which is the focus of this report.…”