SMARCA4-deficient lung tumour that presented with haemoptysis and progressed rapidly.

The case of a heavy ex-smoking man in his early 70s who presented with haemoptysis and died following rapid progression is presented. The tumour excised by surgery was mostly composed of monotonous large rhabdoid cells showing prominent nucleoli and eosinophilic cytoplasm. On immunohistochemistry with SMARCA4 (BRG-1), the tumour cells showed significant loss of expression.