Complete Pathologic Response of Squamous Cell Carcinoma Abutting an Internal Mammary Bypass Graft

We present a case of an advanced squamous cell carcinoma encroaching on a patient's left internal mammary artery bypass graft. Tumor board consensus was to proceed with 2 cycles of neoadjuvant chemotherapy followed by resection. Intraoperatively, the left internal mammary artery bypass could not be safely dissected from the adjacent pleura, but frozen sections were negative for malignant transformation. Final pathologic examination showed a complete pathologic response to neoadjuvant chemotherapy, and surveillance imaging is now negative for recurrence 5 years postoperatively. Although malignant neoplasms invading into adjacent vasculature can post technical challenges during an operation, neoadjuvant therapy can downstage these tumors and make resection feasible without added morbidity.