YO9 - Elevated pleural soluble mesothelin-related peptides do not always means mesothelioma: a case report

Date 18 December 2016
Event ESMO Asia 2016 Congress
Session Poster lunch
Topics Gynaecological Malignancies
Presenter Shunkichi Ikegaki
Authors S. Ikegaki1, Y. Kataoka1, H. Matsumoto1, E. Saito1, H. Yano2, R. Yasumizu3, M. Hirabayashi1
  • 1Department Of Respiratory Medicine, Hyogo Prefectural Amagasaki General Medical Center, 660-8550 - Amagasaki/JP
  • 2Department Of Gynaecology, Hyogo Prefectural Amagasaki General Medical Center, 660-8550 - Amagasaki/JP
  • 3Department Of Surgical Pathology, Hyogo Prefectural Amagasaki General Medical Center, 660-8550 - Amagasaki/JP

Abstract

Case Summary

Background: Soluble mesothelin-related peptides (SMRP) are variant forms of cell surface glycoprotein expressed in mesothelial cells. SMRP are highly expressed in malignant pleural mesothelioma (MPM). A meta-analysis has shown that pleural SMRP are a useful diagnostic marker for MPM. We report herein the case of a patient with primary peritoneal carcinoma with high pleural SMRP.

Case Description: A 67-year-old Japanese women with smoking history presented with dyspnoea. She lived in an industrial region in Japan and had history of environmental exposure to asbestos. Computed tomography revealed right pleural effusion and moderate ascites. We initially suspected MPM and performed thoracentesis. Analysis of pleural effusion revealed elevated SMRP (91.6 nmol/L; cutoff <1.5 nmol/L). Cytology revealed malignant cells. Immunohistochemical analysis of the cell block showed positive results for cytokeratin 7 and negative results for cytokeratin 20, apsin A, thyroid transcription factor 1, D2-40, and calretinin, inconsistent with MPM. Serum cancer antigen 125 was significantly elevated. The cytology of ascites revealed adenocarcinoma. Since no ovary tumour was detected on magnetic resonance imaging, we finally diagnosed primary peritoneal cancer associated with malignant pleural effusion.

Discussion: Elevated pleural SMRP usually indicate a diagnosis of MPM. However, since mesothelin is also overexpressed in ovarian and peritoneal cancer, SMRP are not specific to mesothelioma. This case implies that peritoneal cancer should be considered in patients with elevated pleural SMRP and ascites.