ABSTRACT Despite recent advances in multimodal management, pancreatic ductal adenocarcinoma remains a fatal malignancy. Early detection of indirect findings of pancreatic ductal adenocarcinoma is essential to improve treatment outcomes, drawing attention to pancreatic parenchymal atrophy. Pancreatic parenchymal atrophy, defined as the narrowing of the parenchyma below a line connecting the cephalic and caudal margins of the lesion on computed tomography, can predict early‐stage pancreatic ductal adenocarcinoma and its intraductal extension. Computed tomography with three‐directional imaging is the ideal initial modality for diagnosing pancreatic parenchymal atrophy. In patients with early pancreatic ductal adenocarcinoma, pancreatic parenchymal atrophy exhibits a significantly longer intraductal lateral tumor extension. Pancreatic parenchymal atrophy can be resected using an appropriate‐margin pancreatectomy with a low risk of positive surgical margins. However, the appropriate surgical margin length for each case remains unclear. Carcinoma in situ may be present only within a focal pancreatic parenchymal atrophy region, and pancreatic duct changes may not be present. For such patients, a surgical strategy of limited pancreatectomy with a smaller surgical margin, combined with additional intraoperative resection based on frozen‐section results, is acceptable. Although the relationship between carcinoma in situ and fatty replacement of the pancreatic parenchyma has been investigated, the underlying mechanism remains unclear.
Fujino et al. (2026) studied this question.