Prognostic Significance of Ki67 Expression in Malignant Peritoneal Mesothelioma. (August 2015)

• Record Type: Journal Article
• Authors: Pillai, Krishna; Pourgholami, Mohammad H.; Chua, Terence C.; Morris, David L.
• Is Part Of: American journal of clinical oncology. Volume 38:Number 4(2015)
• Publication Date: 2015-08
• Subjects: mesothelioma -- immunohistochemistry -- Ki67 -- prognosis; Cancer -- Treatment -- Periodicals; Oncology -- Periodicals; Tumors -- Periodicals; 616.994005
• DOI: 10.1097/COC.0b013e3182a0e867
• Languages: English
• ISSNs: 0277-3732

Abstract

Abstract : Objectives: Although Ki67 measurement by immunohistochemistry has been widely used as a prognostic index in cancers, it has not been reported in malignant peritoneal mesothelioma (MPM). Hence, this study examines the prognostic significance of Ki67 in MPM. Methods: Specimens from 42 MPM patients were screened for Ki67 expression using immunohistochemistry. Ki67 expression was classified into 2 groups on the basis of expression (<25%=low; ≥25%=high) using standard methods. Using Kaplan-Meier survival analysis, the significance of Ki67 was assessed in different clinicopathologic categories. Results: High expression of Ki67 (≥25% by immunohistochemical evaluation) was correlated with poor survival in the overall group ( P =0.001); male sex ( P =0.001); female sex ( P =0.001); epithelioid tumors ( P =0.001): male epithelioid ( P =0.001), female epithelioid ( P =0.003); peritoneal cancer index (PCI): PCI<20 ( P =0.001), PCI≥20 ( P =0.002); and age at diagnosis (AAD): AAD<60 years ( P =0.001), AAD≥60 years ( P =0.004). Independent of Ki67, male sex ( P =0.007), sarcomatoid histology ( P =0.001), PCI≥20 ( P =0.013), and AAD≥60 years ( P =0.004) correlated with poor survival. Multivariate analysis showed that only AAD≥60 years ( P =0.049) and high Ki67 expression for all tumors ( P =0.031), male sex ( P =0.038), female sex ( P =0.021), epithelioid tumors ( P =0.044), and AAD<60 years ( P =0.029) were statistically significant. Conclusions: Ki67 expression affects prognosis in MPM patients and helps to predict survival within the various clinicopathologic categories.