A sarcomatoid malignant mesothelioma diagnostic challenge even on immunohistochemistry

Abstract

Sarcomatoid mesothelioma a rare variant accounts for 10-15% of malignant mesothelioma having a fatal outcome. Therefore it becomes essential to differentiate sarcomatoid mesothelioma from other variants. Morphologically it mimics malignant spindle cell tumor. Immunohistochemistry therefore becomes mandatory to offer definitive diagnosis. However IHC markers also show overlapping expression, making its interpretation difficult. In such challenging situations, clinicoradiological features, morphology together with panel of IHC markers help to solve the riddle/dilemma. Here we report a case of sarcomatoid mesothelioma with its varied IHC profile posing diagnostic challenge.