Outcomes of nonresected main-duct intraductal papillary mucinous neoplasms of the pancreas

Table 1 Main characteristics of patients n (%)

Characteristic	Total population, n = 124	Surgical patients, n = 74	Nonsurgical patients, n = 50	P value1
Age at diagnosis (yr), mean ± SD (range)	64.4 ± 9.0 (33-82)	61.2 ± 7.0 (33-73)	69.0 ± 8.0 (58-2)	< 0.01
Sex ratio, male:female	74:50	46:28	28:22	0.57
Associated non-pancreatic cancers2	26 (22.0)	10 (13.5)	16 (32.0)	0.02
Symptoms	96 (77.5)	61 (82.5)	35 (70.0)	0.12
Acute pancreatitis	45 (36.0)	32 (43.0)	13 (36.0)	0.06
Diabetes	15 (12.0)	12 (16.0)	3 (6.0)	0.10
Jaundice	13 (10.4)	7 (13.5)	6 (12.0)	0.76
Others	23 (18.5)	10 (13.5)	13 (26.0)	0.10
Fortuitous	28 (22.5)	13 (17.5)	15 (30.0)	0.12
Localization of IPMN
Head	93 (75.0)	58 (78.5)	35 (70.0)	0.29
Body	12 (9.5)	6 (8.5)	6 (12.0)	0.54
Tail	10 (8.0)	5 (6.5)	5 (10.0)	0.52
Diffuse	9 (7.5)	5 (6.5)	4 (8.0)	1.00
Involvement of branch duct (mixed forms)	101 (81.5)	59 (79.0)	42 (84.0)	0.64
Maximal diameter of main duct at diagnosis, mm	7.6 ± 0.4 (6)	7.2 ± 0.4 (6)	8.3 ± 0.9 (6)	0.19
mean ± SD (median)
Tissue nodule or wall thickening at imaging3	36 (29.0)	21 (28.0)	15 (30.0)	0.84
Malignant invasive IPMN	62 (50.0)	41 (55.5)	21 (40.0)4	0.19
Follow-up after diagnosis (mo), median (range)	24 (162-6)	24 (162-9)	30 (141-6)	0.85
Death	41 (33.0)	19 (26.0)	22 (44.0)	0.05

¹Nonsurgical vs surgical groups;

²Lung: n = 5, prostate: n = 7, hemopathy: n = 3, mammary: n = 3, colon: n = 2, miscellaneous: n = 6;

³Main pancreatic duct or branch-duct cyst, or both, mainly visualized by endoscopic ultrasound;

⁴Occurrence during follow-up in 18 patients. IPMN: Intraductal papillary mucinous neoplasm.

Table 2 Characteristics of nonsurgical patients with progression of malignancy in the main duct or mixed intraductal papillary mucinous neoplasm of the pancreas

Age, yr	Sex	Localization	At diagnosis		Clinical outcome	Time until progression, mo
			Symptoms	Size of the main duct, mm
72	F	Head	Acute pancreatitis	10	Jaundice	141
76	F	Head	Pain	7	Jaundice	129
73	M	Head	Acute pancreatitis	14	Ascites	61
71	M	Diffuse	Acute pancreatitis	10	None	59
80	F	Head	Fortuitous	6	Jaundice	65
72	M	Diffuse	Fortuitous	60	Occlusion	49
78	M	Body	Pain, weight loss	5.5	Ascites	40
69	M	Head	Fortuitous	7	Jaundice	39
71	F	Head	Weight loss	6	Jaundice	30
66	M	Body	Fortuitous	15	Ascites	28
82	F	Head	Pain, weight loss	10	Jaundice	24
82	M	Head	Fortuitous	6	Painful	12
67	F	Diffuse	Jaundice	10	Jaundice	12
54	M	Head	Pain	17	Jaundice	12
67	F	Tail	Fortuitous	5	None	12
77	M	Head	Fortuitous	5.5	Jaundice	9
80	F	Head	Weight loss	6	Jaundice	8
76	F	Body	Pain	7	Painful	8

M: Male; F: Female.

Table 3 Comparison of the main characteristics of patients in the nonsurgical subgroup with and without progression of malignancy of the main duct or mixed intraductal papillary mucinous neoplasm of the pancreas n (%)

Characteristic	Nonresected IPMN with malignant progression, n = 18	Nonresected IPMN without malignant progression, n = 32	P value
Age1 (yr), mean ± SD	73.0 ± 7	68.5 ± 8.0	0.06
Sex, male:female	9:9	19:13	0.56
With symptoms	11 (61)	24 (75)	0.34
Size of the MPD (mm), mean ± SE (median)1	11.5 ± 3.0 (7.0)	6.9 ± 0.4 (5.7)	< 0.05
Mixed form	13 (72)	29 (90)	0.11
Size of the BD1 (mm), mean ± SE (median)1	27.3 ± 4.3 (25.0)	22.2 ± 2.6 (17.0)	0.30
Tissue nodule or wall thickening2	8 (44)	7 (22)	0.11
Follow-up time after diagnosis (mo), median	29	30	0.6

¹At diagnosis;

²MPD and/or branch-duct cyst. BD: Branch duct; IPMN: Intraductal papillary mucinous neoplasm; MPD: Main pancreatic duct.

Table 4 Analysis of prognostic factors in 124 patients with a resected or nonresected main-pancreatic duct and mixed intraductal papillary mucinous neoplasm of the pancreas

Variable (n)	Univariate analyses by log-rank test		Multivariate analyses by Cox’s model
	RR (95%CI)	P value	HR (95%CI)	P value
Surgery		0.02		0.08
No (50)	1		1
Yes (74)	0.48 (0.26-0.88)		0.54 (0.27-1.09)
Age at diagnosis		0.01		0.13
< 70 yr (83)	1		1
≥ 70 yr (41)	2.36 (1.26-4.40)		1.72 (0.86-3.46)
Extra-pancreatic cancer		0.13		-
No (98)	1		-
Yes (26)	1.66 (0.86-3.22)		-
MPD size > 10 mm		0.13		-
No (100)	1		-
Yes (24)	1.66 (0.86-3.22)		-
Nodule1		0.01		0.01
No (88)	1		1
Yes (36)	2.42 (1.17-5.00)		2.71 (1.29-5.69)
BD size > 30 mm		0.85		-
No (94)	1		-
Yes (30)	1.08 (0.51-2.29)		-
Fortuitous		0.63		-
No (96)	1		-
Yes (28)	1.19 (0.58-2.45)		-
Acute pancreatitis		0.24		-
No (79)	1		-
Yes (45)	0.68 (0.35-1.30)		-

¹Nodule and wall thickening of MPD and/or branch-duct cysts. BD: Branch duct; MPD: Main pancreatic duct.

Table 5 Results from followed patients with non-operated main-duct or mixed intraductal papillary mucinous neoplasm of the pancreas

Ref.	Patients, n	Malignant progression	Time to progression in month, mean (range)	Predictors of malignant progression
Uehara et al[17], 2010	20	40%	(20-35)	None1
Takuma et al[18], 2011	20	20%	32 (17-65)	Dilatation of the MPD > 10 mm
Ogura et al[16], 2013	20	40%	30 (18-46)	Dilatation of the MPD > 15 mm; diffuse lesions
Roch et al[36], 2014	70	13%	42 (12-108)	Diffuse dilatation of the MPD2
Present study	50	36%	33 (8-141)	Dilatation of the MPD > 10 mm

¹Intraductal papillary mucinous neoplasm with lower likelihood of malignancy at baseline;

²Also included an increase in serum carbohydrate antigen 19-9 and alkaline phosphatase levels, absence of extra pancreatic cyst. MPD: Main pancreatic duct.