Table 2.
Margin involvement
| Margin | Based on CAP approach | Based on author's approach | |
|---|---|---|---|
| (0 mm rule) | (1 mm rule) | ||
| SMAM | 9a | 9a | 14 |
| SMVM | - | 9 | 18 |
| PUPM | - | 1 | 5 |
| PNM | 1 | 1 | 1 |
| BDM | 1 | 1 | 1 |
| Total R1 | 9b | 14b | 20b |
a
In one patient, the SMAM was involved by metastatic carcinoma in a lymph node and this patient was not included as it was considered as locoregional metastasis.
b
Owing to multifocality of resection margin involvement within the same specimen in some patients, the total number of involved margin exceeds the total number of patients with an R1 margin.
BDM, Bile duct margin; CAP, College of American Pathologists; PNM, Pancreatic neck margin; PUPM, Posterior surface of the uncinate process margin; SMAM, Superior mesenteric artery margin; SMVM, Superior mesenteric vein margin.