Objective: To review the clinical presentation and imaging findings of adenoid cystic carcinoma (ACC).
Material and methods: We performed a retrospective study of the period between January 1990 and July 2004, comprising five cases of ACC of the breast, all in women, among 4,036 malignant lesions diagnosed (0.12%). We reviewed the available imaging studies (mammography in all five cases, ultrasound in four, and magnetic resonance in one). We also reviewed the clinical presentation and evolution in all patients.
Results: Three patients presented with palpable lesions. Mammographic findings consisted of irregular, ill-defined nodules in three cases, a well-defined rounded nodule in one, and an asymmetrical density in the other. No microcalcifications were observed in any case. Ultrasound examination showed ill-defined polylobulated nodules in three cases and a well-defined, rounded nodule with small cysts inside in the remaining case that showed intense vascularization in the Doppler study. The only case studied by magnetic resonance was seen as a rounded nodule that showed heterogeneous contrast uptake, well-defined margins, and an enhancement curve considered highly suspicious for malignancy. Treatment was tumorectomy together with radiotherapy in all cases. Four patients remain asymptomatic at present (mean follow-up = 64 months) and one presented lung and liver metastes twelve years after the diagnosis of ACC.
Conclusion: ACC is an uncommon breast tumor with varied radiologic appearance, although moderately or highly suspicious lesions predominate. We consider the absence of microcalcifications in these tumors to be noteworthy. The prognosis is generally good, although the possibility of remote metastasis exists.