Table 5

Scoring of intraductal ultrasononographic findings and frequency of malignancy on final diagnosis

No positive factors on IDUSFrequency of malignancy on final diagnosis*
Positive factors in predicting malignancy on intraductal ultrasonography (IDUS ) findings: (1) presence of sessile tumour (intraductal or outside of the bile duct); (2) tumour size greater than 10.0 mm; and (3) interrupted wall structure.
*The process of final diagnosis is shown in table 4.
(1) Total cases (n=62)
    0 2/17 (12%)
    1 5/7 (71%)
    2–337/38 (97%)
(2) Cases with no evidence of malignancy on the histological findings of biopsy specimen (n=31)
    0 0/15 (0%)
    1 2/4 (50%)
    2–311/12 (92%)