Teaching Case

A 51-year-old female patient presented with focal skin erythematous changes in the left breast in its upper outer quadrant near the nipple for 2 months, nipple looks normal, no retraction and no pain. The patient denied any nipple discharge, history of trauma, intervention or any medical illness. No other abnormalities.

The patient presented to do a mammogram that showed equal density, oval, circumscribed mass in the upper outer quadrant left breast in its mid-depth (Figs. 1a and b).

Ultrasound  gray scale demonstrates a circumscribed oval hypoechoic mass opposite 1 o’clock, 5 cm from the nipple measures 1.0 x 0.7 cm. Left axillary LN showed thickened cortex measured 0.5 cm. Gray and colour-coded Doppler showed cystic lesion with intrinsic echoes due to small thrombus or slow flow, and showed complete colour filling with swirling appearance (Fig 1c and d) arterial waveform seen in pulsed Doppler (Fig. 1e). Diagnosis of left-breast aneurysm was made. Further assessment with MRI with contrast was done, MIP (Figs. 1f and g) and volume rendering images were obtained that confirm the diagnosis (Figs. 1h and i). No suspicious masses or suspicious enhancement seen.

Biopsy of the left axillary lymph node was taken to exclude being secondary to underlying breast sinister occult lesion, that revealed dermatopathic lymphadenopathy. The patient seen by breast surgeon and follow-up after three months was planned.

The main arterial supply of the breast is from the internal mammary, lateral thoracic and intercostal arteries. The breast vascular disease includes atherosclerosis which is the most common, true and pseudo-aneurysm, arterio-vascular malformation and vascular tumours [1]. Breast aneurysm is a rare entity with few reported cases, most of them are secondary to prior trauma, biopsy [2,3] and operations like lumpectomy [4] and breast implants [5]. Few cases were reported secondary to spontaneous haemorrhage due to coagulopathies or uncontrolled hypertension [6-7] and some are idiopathic with no underlying cause that is seen in our case as the patient has no history of trauma, operation, biopsy or hypertension. The aneurysm is usually asymptomatic especially if it is small in size , sometimes presented with a slowly enlarging palpable mass or pain particularly in false aneurysm or skin changes [8]. In our case, the patient is asymptomatic and presented with incidental skin changes that diagnosed to be irrelevant to the incidental finding of breast small aneurysm. The treatment of the aneurysm includes thrombin or alcohol injection, external compression, coiling and surgical repair as well as conservative management [9]. In our case, the patient and surgeon prefer to follow-up as the aneurysm is small and asymptomatic.

Multiple imaging modalities are used to diagnose breast vascular lesions in particularly breast ultrasound with colour-coded and spectral Doppler and breast MRI with contrast together with MIP images. The diagnosis of a breast aneurysm may be suspected on clinical grounds [10] in some cases. In our case, Doppler US of the breast is the ideal modality to diagnose the condition, and additional post-contrast breast MRI is used to confirm and localise the lesion and exclude the presence of other masses. Although aneurysms in the breast are rare, it should be included in the differential diagnosis of any breast mass [11].

Breast aneurysm should be considered in differential diagnosis of the breast masses. Colour Doppler should be applied to all breast masses to avoid missing vascular lesions and to avoid inadvertent aneurysm biopsy. Aneurysm can be seen without history of trauma or intervention, as it can happen spontaneously.

Written patient consent for this case was waived by the Editorial Board. Patient data may have been modified to ensure patient anonymity.