The case is presented of a coal miner with bilateral masses of progressive massive fibrosis, who developed acute cavitation following fibreoptic bronchoscopy and biopsies. Indeed, immediately upon bronchoscopy with transbronchial biopsy, there was expectoration of abundant melanoptysis. Three days later, the chest radiograph showed a cavity and the patient again coughed up black material, in the context of pulmonary infection. One week later, there was complete emptying of the conglomerate mass. To the authors' knowledge, this is the first reported case of a conglomerate mass of progressive massive fibrosis which cavitated as a result of bronchoscopy.