1. Department of Surgery, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
2. Department of Surgery, Legacy Emanuel Medical Center, 2801 N. Gantenbein, Portland, OR 97227, USA
3. Portland Providence Cancer Center, 4805 NE Glisan Street, Portland, OR 97213, USA
4. The Oregon Clinic, 4805 NE Glisan Street, Portland, OR 97213, USA