unresectable

Unresectable is a medical term used primarily in oncology to describe tumors or lesions that cannot be removed by surgery in a way that would achieve clear margins or acceptable postoperative function. The designation can reflect anatomical constraints, tumor biology, or patient factors. It is distinct from resectable disease, which can be removed with curative intent, and from borderline resectable disease, where surgery might become possible after preoperative therapy.

Reasons a lesion may be deemed unresectable include invasion or encasement of major vessels or critical structures, multifocal or widespread disease that would preclude complete removal, extensive peritoneal carcinomatosis or distant metastases, and poor patient performance status or comorbidities that render surgery too risky. Examples across cancer types include pancreatic tumors with involvement of the celiac axis or mesenteric vessels, hepatocellular carcinoma with diffuse multifocal disease or vascular invasion, and glioblastoma with infiltration of eloquent brain regions. However, resectability status can change with advances in imaging, surgical techniques, and neoadjuvant therapy.

Assessment is typically performed by a multidisciplinary team using imaging studies such as CT, MRI, and PET, sometimes complemented by diagnostic laparoscopy. Management shifts toward disease control and palliation, employing chemotherapy, radiotherapy, targeted therapies, immunotherapy, or ablation, and in some cases debulking procedures. In certain situations, neoadjuvant therapy may convert unresectable disease to resectable, illustrating the fluid nature of the term.