Aim to describe the mammographic and ultrasonographic features of pure mucinous breast cancer.
Patients and methods: The mammographic features of 15 patients and ultrasonographic features of seven patients with pure mucinous breast cancer were reviewed retrospectively by three experienced breast radiologists.
Results: The commonest mammographic appearance was of a poorly defined (86%) lobulated (71%) mass which could contain calcification (14%). A well defined mass (14%) and suspicious calcifications without a mass (7%) were also seen. Ultrasound showed a mass lesion in all seven cases which was either hypoechoic (86%) or mixed echogenicity (14%); 86% had a heterogeneous internal echo pattern; 71% showed distal enhancement while none showed distal attenuation.
Conclusion: The imaging features of pure mucinous cancer are different from more common types of breast carcinoma. It is possible to misinterpret the appearances of this slow growing tumour as a benign lesion due to rarity of speculation on mammography and distal attenuation on ultrasonography. Most cases do, however, show other features suggesting malignancy.