Malignancy is as likely to occur in small cysts (<3 cm) as it is to occur in large cysts (>3 cm).

In any size category, the majority of cysts are benign.

                                          Benign                        Malignant

• <1 cm                         41 (95%)                      2 (5%)
• 1-2 cm                       168 (92%)                    14 (8%)
• 2-3 cm                       86 (90%)                      10 (10%)
• >3 cm                         77 (78%)                      22 (22%)