Massive fatal pulmonary haemorrhage during bevacizumab treatment following microwave ablation therapy for oligometastatic lung metastasis from rectal cancer

Although thoracic ablative therapies are generally safe procedures, fatal complications can occur. Bevacizumab is a standard-of-care treatment along with chemotherapy for metastatic colorectal cancer. Although uncommon, unpredictable serious adverse events can occur secondary to bevacizumab. We report a case of fatal intrapulmonary haemorrhage as a result of arteriopulmonary fistula in a patient after microwave ablation of pulmonary colorectal cancer metastasis while on bevacizumab. Antiangiogenetic properties of bevacizumab are associated with delayed wound healing, which might have been a crucial factor in the development of arteriopulmonary fistula and haemorrhage.