Predictive factors associated with malignancy of intraductal papillary mucinous pancreatic neoplasms

Table 1 Demographics and subtypes of intraductal papillary mucinous neoplasms (n = 129) (mean ± SD) n (%)

Features	Value
Age (yr)	60.9 ± 9.6 (range, 32-77)
Sex (M:F)	94:35
Symptoms
(-)	66 (51.2)
(+)	63 (48.8)
Mean tumor size (cm)	3.7 ± 3.2 (range, 0.6-16.5)
Mean MPD size (mm)	7.4 ± 4.8 (range, 1.0-30.0)
Tumor location
Pancreatic head or uncinate process	80 (62.0)
Body or tail	49 (28.0)
Duct types on CT
Main duct	56 (43.4)
Branch duct	46 (35.7)
Mixed duct	27 (20.9)
Pathologic subtypes
Adenoma	51 (39.5)
Borderline	30 (23.3)
CIS	5 (3.9)
Invasive	43 (33.3)

MPD: Main pancreatic duct; CT: Computed tomography; CIS: Carcinoma in situ.

Table 2 Univariate analysis of preoperative findings associated with malignant intraductal papillary mucinous neoplasms of the pancreas

Factor	Benign (n = 81)	Malignant (n = 48)	P value
Age (yr)
< 60	27	24	0.063
≥ 60	54	24
Sex
Male	64	30	0.064
Female	17	18
Alcohol
Non-alcoholic	50	37	0.083
Alcoholic	31	11
Smoking
Non-smoker	53	35	0.437
Current smoker	28	13
Diabetes mellitus
No	59	30	0.242
Yes	22	18
Symptoms
No	49	17	0.007
Yes	32	31
Tumor size (cm)
≤ 4	66	30	0.019
> 4	15	18
MPD diameter (mm)
≤ 7	54	18	0.002
> 7	27	30
Mural nodules on CT
No	77	44	0.469
Yes	4	4
Amylase (U/L)
≤ 100	53	37	0.173
> 100	28	11
Total bilirubin (mg/dL)
≤ 1.2	75	41	0.231
> 1.2	6	7
CEA ( ng/mL)
≤ 6	79	48	0.529
> 6	2	0
CA 19-91 (U/mL)
≤ 37	65	32	0.063
> 37	10	12
Location in pancreas
Head	52	28	0.575
Body or tail	29	20
Intra-abdominal lymphadenopathy on CT
No	73	33	0.003
Yes	8	15
Duct type
Main or mixed	47	36	0.059
Branch duct	34	12
Extrapancreatic malignancy
No	61	45	0.014
Yes	20	3

¹Missing data on CA 19-9 in some patients was presented. MPD: Main pancreatic duct; CT: Computed tomography; CEA: Carcinoembryonic antigen; CA: Carbohydrate antigen.

Table 3 Characteristics of intraductal papillary mucinous neoplasms with extrapancreatic malignancies

No.	Sex	Age (yr)	Diagnosis	Extrapancreatic malignancy	Time of occurrence
1	M	62	Adenoma	Early gastric cancer	Syn
2	M	55	Adenoma	Early gastric cancer	Syn
3	M	66	Adenoma	Colon tubular adenoma	Syn
4	M	58	Borderline	Advanced gastric cancer	Prior
5	F	54	Adenoma	Advanced gastric cancer	Syn
6	F	72	Adenoma	Advanced gastric cancer	Syn
7	F	70	Adenoma	Appendix mucinous tumor	Syn
8	M	64	Adenoma	Colon cancer	Prior
9	M	72	Borderline	Colon cancer	Prior
10	M	56	Invasive	Colon cancer	Syn
11	M	59	Adenoma	Early gastric cancer	Syn
12	M	48	Borderline	Early gastric cancer	Prior
13	M	60	Adenoma	Early gastric cancer	Prior
14	M	67	Adenoma	Early gastric cancer	Syn
15	M	62	Borderline	Early gastric cancer	Syn
16	M	53	Adenoma	Gastric SMT	Prior
17	M	66	CIS	Prostate cancer	Prior
18	M	68	Adenoma	Renal cell carcinoma	Syn
19	M	64	Adenoma	Rectal cancer	Prior
20	M	74	Adenoma	Rectal cancer	Prior
21	M	76	Adenoma	Rectal cancer	Prior
22	F	60	Adenoma	Rectal cancer	Syn
23	M	61	Adenoma	Rectal carcinoid tumor	Syn

SMT: Submucosal tumor; CIS: Carcinoma in situ; Prior: Prior to intraductal papillary mucinous neoplasm (IPMN); Syn: Synchronous to IPMN.

Table 4 Multivariate analysis of preoperative findings associated with malignant intraductal papillary mucinous neoplasms

Factors	OR	95% CI	P value
Extrapancreatic malignancy - none	3.58	0.95-13.51	0.059
Symptomatic	1.89	0.83-4.32	0.127
Tumor size > 4 cm	2.35	0.96-5.76	0.062
MPD diameter > 7 mm	2.50	1.10-5.65	0.028
Preoperative CT lymphadenopathy	3.57	1.22-10.37	0.020

MPD: Main pancreatic duct; CT: Computed tomography; OR: Odds ratio; CI: Confidence interval.

Table 5 Immunohistochemical staining of intraductal papillary mucinous neoplasms n (%)

Markers	Benign IPMN	Malignant IPMN
MUC1	2/9 (22.2)	3/15 (17.6)
MUC2	8/27 (29.6)	8/14 (57.1)
MUC5AC	26/27 (96.3)	16/17 (94.1)
p53	2/18 (11.1)	10/29 (34.5)

IPMN: Intraductal papillary mucinous neoplasm; MUC: Mucin.