Cytopathology and Histopathology

Biography

Biography: Jamshid Abdul-Ghafar

Abstract

Introduction: Malignant mesothelioma (MM) is well known as aggressive cancer which has the resistance to usual treatments and show poor prognosis. Little has been reported regarding the effective therapeutic methods of MM. Recently, epidermal growth factor receptor (EGFR) gene has been introduced that it has important role in the biologic features and tumor growth of the pleural MM, and the novel therapeutic agent such as EGFR tyrosine kinase inhibitor attempt to treatment of MM. We evaluated the expression of EGFR gene using Immunohistochemical stains (IHC), fluorescence in situ hybridization (FISH), and EGFR gene mutation in cases of MM of Korean patients. Methods: We reviewed clinicopathologic findings for 44 cases. The mean age of cases (male 32, female 12) was 59 years old (19-79). Most cases were occurred in the pleura (38 cases, 83.4%) and 6 cases (13.6%) from the peritoneum. The IHC for EGFR antibody for 29 cases, FISH analyses for 17 cases and detection of EGFR gene mutation for 36 cases were performed. The histologic subtypes were epithelioid in 31 (70.5%), biphasic in 5 (11.4%), desmoplastic in 3 (6.8%), and other variants in 5 (11.4 %). Results: On the result of IHC stains for EGFR, 7 cases (24.1%) showed positive expression. According to the EGFR FISH analysis only 2 cases (11.8%) revealed a positive gene copy number gain of EGFR (high polysomy), both cases were in IHC-positive group. Thirty-five cases of MM did not show any EGFR mutation. EGFR mutation was found in only one case of MM on exon 21, L861. Conclusion: EGFR overexpression is relatively common in epithelioid type of MM. The protein expression of EGFR is not significantly related to a gene copy number gain and nor related to EGFR mutation. However, the further studies to the larger group in future are expected.