To the editor:We read with a great interest the article by Olsen et al.1 They described a good case of metastatic scalp angiosarcoma with rapidly enlarging lung cysts and pleural effusion.Scalp angiosarcoma is rare and has a predilection for pulmonary metastases.2,3 The metastases on chest radiographs are initially subtle and easily missed.We report a patient who presented with multiple thin-walled lung cysts and pneumothorax,and was delayed in the diagnosis for more than three months.