Detection of point mutation in K-ras oncogene at codon 12 in pancreatic diseases

Table 1 Relative frequency of K-ras mutation in ductal lesions with pancreatic diseases

Ductal lesion	n	K-ras(-)	K-ras(+)	Positivepercentage (%)
Pancreatic ductal	24	5	19	79.2
adenocarcinoma
Peritumoral ductal	19	15	14	73.6
atypical hyperplasia
Peritumoral ductal	58	38	20	34.5
hyperplasia
Normal duct at the tumor	16	16	0	0
free resection margin
Chronic pancreatitis	24	16	8	33.3
Normal pancreas	7	7	0	0

Table 2 K-ras mutation pattern of ductal lesions and the cor-responding primary pancreatic carcinoma

Ductal lesion	Nucleotide sequenceof K-ras12 codon
	GAT	GTT	CGT
Pancreatic ductal adenocarcinoma	8	4	7
Peritumoral ductal atypical hyperplasia	7	2	3
Peritumoral ductal hyperplasia	10	3	7
Chronic pancreatitis	4	2	2

Table 3 Relationship between K-ras gene mutation and location, histologicalal grade and clinical stage of pancreatic carcinomas

Pathologic factor	n	Positive rate (%)
Tumor location
Head	18	55.6
Tail/Corpus	6	66.7
Histological grade
G1	6	66. 7
G2	10	50
G3	8	62.5
Clinical stage
I	1	100
II	3	66.7
III	9	66.7
IV	11	45.5

Table 4 Clinical and morphologic data on 24 patients with chronic pancteatitis

	K-ras positive cases (n = 8)	K-ras negative cases (n = 16)
Mean age of patients (yrs)	39.9 ± 15.5(19 - 68)	51 ± 14.9(23 - 67)
Gender ratio (M:F)	6:2	10:6
Mean duration of CP (yrs)	6.7 ± 3.2(2 - 27)	5.7 ± 4.5(3 - 25)
Mass-CP of pancreatic head	5 cases	10 cases
Weight loss (> 10 kg)	3 cases	7 cases
Diabetes (insulin dependent)	4 cases	7 cases
Nicotine(> 20 cigarettes/day, > 5 yrs)	5 cases	8 cases

CP: chronic pancreatitis.