Table II.
Imaging characteristics of intraductal mucinous neoplasm of the pancreas (IPMN) stratified by differential involvement of pancreatic ducts
| Characteristics | Branch-duct IPMN (n = 175)
|
Mixed-type IPMN with minimal main-duct involvement (n = 46)
|
Mixed-type IPMN with extensive main-duct involvement (n = 163)
|
Main-duct IPMN (n = 20)
|
P value* | P value† | P value‡ | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | n | % | ||||
| Dominant location | |||||||||||
| Head | 113 | 65 | 34 | 74 | 98 | 60 | 11 | 55 | .008 | .22 | .20 |
| Distal | 26 | 15 | 11 | 24 | 57 | 35 | 6 | 30 | — | — | — |
| Entire pancreas | 36 | 21 | 1 | 2.2 | 8 | 4.9 | 3 | 15 | — | — | — |
| Multifocal lesions | 52 | 30 | 7 | 15 | 21 | 13 | 1 | 5 | .048 | .68 | .31 |
| Size (at operation) diameter, median, range (mm) | 25 | 6–86 | 28 | 5–60 | 22 | 5–160 | 30 | 10–90 | .73 | .77 | .56 |
| MPD component | |||||||||||
| Diameter, median, range (mm) | 2 | 2–9 | 2 | 2–12 | 9 | 2–140 | 30 | 10–90 | <.0001 | <.0001 | .002 |
| MPD dilation (≥5 mm) | |||||||||||
| Segmental | 48 | 27 | 15 | 33 | 61 | 37 | 6 | 30 | .11 | <.0001 | .13 |
| Diffuse | 0 | 0 | 1 | 2.2 | 82 | 50 | 14 | 70 | — | — | — |
| No dilation | 127 | 73 | 30 | 65 | 20 | 12 | 0 | 0 | — | — | — |
| Branch-duct component | |||||||||||
| Macroscopic (≥ 10 mm) | 160 | 91 | 43 | 93 | 101 | 62 | — | — | .651 | <.0001 | — |
| Macroscopic (<10 mm) | 15 | 8.6 | 3 | 6.5 | 42 | 26 | — | — | — | — | — |
| Microscopic only | 0 | 0 | 0 | 0 | 20 | 12 | — | — | — | — | — |
*
P value between mixed-type IPMN with minimal main-duct involvement and branch-duct IPMN.
†
P value between mixed-type IPMN with minimal main-duct involvement and that with extensive main-duct involvement.
‡
P value between mixed-type IPMN with extensive main-duct involvement and main-duct IPMN.
MPD, Main pancreatic duct.