OTP, CD44, and Ki-67 – A prognostic marker panel for relapse free survival in patients with surgically resected pulmonary carcinoid

#3858

Introduction: Relapse occurs in 10% of patients with resected pulmonary carcinoid (PC). While typical carcinoids (TC) show low relapse rates, safe exclusion from long-term follow-up (FU) is impossible partly due to high interobserver variation in the WHO classification.

Aim(s): To examine if an immunohistochemical (IHC) marker panel (OTP, CD44, Ki-67) improves 1) uniformity among pathologists and 2) prediction of relapse free survival (RFS).

Materials and methods: All surgically resected PC (2003-2012) were identified from the Dutch cancer/pathology registry. A case-control cohort (2:1 for relapse, N=170) was established. 4 pathologists independently revised all cases and assessed IHC-markers (OTP&CD44 H-score, Ki-67 eyeball). IHC cut-off values were determined using ROC curve analysis. Agreement between pathologists for diagnostic classification and IHC was determined using kappa. The remaining total cohort (N=396/566) was scored similarly.

Conference:

Presenting Author: Moonen L

Authors: Moonen L, Derks J, den Bakker M, Hillen L, von der Thüsen J,

Keywords: Pulmonary Carcinoid, OTP, CD44, Ki-67, biomarker, prognosis,