title: Tracheal Diverticulum Following Paratracheal Hypofractionated Radiotherapy in the Setting of Prior and Subsequent Bevacizumab.
abstract: We present the case of a 63-year-old woman with limited metastatic colorectal cancer to the lungs and liver treated with FOLFIRI-bevacizumab, followed by consolidative hypofractionated radiotherapy to right paratracheal metastatic lymphadenopathy. We treated the right paratracheal site with 60 Gy in 15 fractions (70 Gy equivalent dose in 2 Gy fractions). The patient tolerated the treatment well, and six months later started a five-month course of FOLFIRI-bevacizumab for new metastatic disease. She presented to our clinic six months after completing this, complaining of productive cough with scant hemoptysis, and was found to have localized tracheal wall breakdown and diverticulum in the region of prior high-dose radiation therapy, threatening to progress to catastrophic tracheovascular fistula. This was successfully repaired surgically after a lack of response to conservative measures. We urge caution in treating patients with vascular endothelial growth factor (VEGF) inhibitors in the setting of hypofractionated radiotherapy involving the mucosa of tubular organs, even when these treatments are separated by months. Though data is limited as to the impact of sequence, this may be particularly an issue when VEGF inhibitors follow prior radiotherapy.
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Aadel A
authors.initials: AA
authors.lastname: Chaudhuri
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Jie Jane
authors.initials: JJ
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Justin N
authors.initials: JN
authors.lastname: Carter
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Binkley
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Kiran A
authors.initials: KA
authors.lastname: Kumar
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine.
authors.forename: Sara A
authors.initials: SA
authors.lastname: Dudley
authors.affiliation: Department of Pulmonary and Critical Care Medicine, Stanford University School of Medicine.
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Sung
authors.affiliation: Department of Radiation Oncology, Stanford University School of Medicine ; Stanford Cancer Institute, Stanford University School of Medicine.
authors.forename: Billy W
authors.initials: BW
authors.lastname: Loo
keywords: bevacizumab; hypofractionated conformal radiotherapy; oligometastatic cancer; tracheal diverticulum; vegf inhibitor; volumetric modulated arc therapy (vmat)