Pathologic Evaluation of Surgical Margins in Pancreatic Cancer Specimens Using Color Coding With Tissue Marking Dyes.

Objectives: Processing of pancreatoduodenectomy specimens is not standardized; the clinical impact of pathologic surgical margins remains controversial. We used the color-coding method using tissue-marking dyes to evaluate margin status of resected specimens to assess its association with postoperative recurrence.
Methods: We developed a unified processing approach to assess pancreatoduodenectomy specimens. Five surgical margins of resected pancreatic specimens were marked with 5 colors. Microscopic resection margin distance (RMD) from margin closest to the tumor was evaluated for each surgical margin. Forty patients assessed using nonunified protocols, and 98 patients assessed using unified protocols were included.
Results: The frequency of tumors with RMD of 1 mm or less in posterior margin was significantly lower and that in portal vein/superior mesenteric vein margin was significantly higher in unified protocol group than in nonunified protocol group (P < 0.001). In unified protocol group, tumors with RMD of 1 mm or less correlated with locoregional recurrence (P = 0.025) and recurrence-free survival (P = 0.030). Multivariate analysis revealed that tumor size and lymph node metastasis were independent indicators for disease recurrence.
Conclusions: Resection margin distance of 1 mm or less was a predictor for disease recurrence, particularly for locoregional recurrence. Early detection of small-sized tumors without lymph node metastasis is necessary for improved clinical outcomes in pancreas cancers.