American Journal of Clinical Pathology 2021 May 12 [Link]

Jefree J Schulte, David B Chapel, Richard Attanoos, Luka Brcic, Juliet Burn, Kelly J Butnor, Nina Chang, Heather Chen, Sanja Dacic, Marc De Perrot, Junya Fukuoka, Francoise Galateau-Salle, Theresa Godschachner, Kenzo Hiroshima, Sonja Klebe, Thomas Krausz, Leslie Litzky, Alberto M Marchevsky, Jeffrey Mueller, Kazuki Nabeshima, Andrew G Nicholson, Prodipto Pal, Anja C Roden, Sara Rorvig, Eric Santoni-Rugiu, Henry Tazelaar, Ming-Sound Tsao, Ann E Walts, Birgit Weynand, Yoshiaki Zaizen, Yu Zhi Zhang, Aliya N Husain

Abstract

Objectives: Numerous studies on malignant mesothelioma (MM) highlight the prognostic importance of histologic subtype, nuclear grade, and necrosis. This study compares these parameters in paired biopsy and resection specimens of pleural MM.

Methods: Histologic subtype, percentage of epithelioid morphology, nuclear grade, and the presence or absence of necrosis were compared in 429 paired biopsies and resection specimens of pleural MM from 19 institutions.

Results: Histologic subtype was concordant in 81% of cases (κ = 0.58). When compared with resection specimens, epithelioid morphology at biopsy had a positive predictive value (PPV) of 78.9% and a negative predictive value (NPV) of 93.5%; sarcomatoid morphology showed high PPV (92.9%) and NPV (99.3%), and biphasic morphology PPV was 89.7% and NPV was 79.7%. Agreement of the percentage of epithelioid morphology was fair (κ = 0.27). Nuclear grade and necrosis were concordant in 75% (κ = 0.59) and 81% (κ = 0.53) of cases, respectively. Nuclear grade showed moderate (κ = 0.53) and substantial (κ = 0.67) agreement from patients with and without neoadjuvant therapy, respectively, and necrosis showed moderate (κ = 0.47 and κ = 0.60) agreement, respectively, in the same subsets of paired specimens.

Conclusions: Paired biopsy-resection specimens from pleural MM show overall moderate agreement in pathologic parameters. These findings may help guide postbiopsy management and triage of patients with MM.