Table 1.

Proposed scoring system for ductoscopic appearances (Mokbel's classification system)

D0	Inadequate views/unsuccessful procedure
D1	Normal mammary ducts
D2	Typically benign appearance
D3	Low index of suspicion/indeterminate most likely benign
D4	Appearances suspicious of malignancy
D5	Appearances suspicious of malignancy plus positive ductscopic cytology