Incidental finding: Venous malformation of the breast

A 45-year-old woman presented to the breast unit with a history of a palpable lump in the upper central part of the left breast. She did not have any relevant risk factors or family history.

On clinical examination, there was a well-defined, mobile mass in the periareolar region of the left breast, classified as clinically benign. Further investigation with bilateral mammogram and ultrasound were requested as per local protocol.

Mammography revealed an oval circumscribed mass in the left periareolar region corresponding to the clinical finding (Figures 1a and 1b). This was confirmed to be a cyst on ultrasound (Figure 2).

Further incidental findings were detected in the right breast. These were multiple circumscribed masses and oval/tubular densities with some micro/macro calcifications within them in the right axillary tail (Figures 1a, 1b and 3). Further assessment with tomosynthesis was requested, which confirmed the presence of multiple tubular densities (Figure 4). A targeted ultrasound revealed a few prominent, compressible anechoic tubular structures. Vascular flow was seen on Doppler ultrasound (Figures 5a and 5b). Further assessment with MRI was performed. This shows multiple lesions located within the pectoral muscle and extending to the adjacent breast soft tissue, hyperintense on T2W images (Figure 6a) and hypointense in T1W images (Figure 6b). Slow flow was demonstrated on T2W images (Figure 6a). The lesions showed mild contrast enhancement in subtracted post-contrast dynamic sequences (Figures 7a and b). Based on the imaging findings, the diagnosis of venous malformation was made.

Background

Venous malformations occur because of errors in endothelial cell morphogenesis. It causes disorganised angiogenesis and intimal smooth muscle proliferation [1]. According to the newer nomenclature of the International Society for the Study of Vascular Anomalies (ISSVA) classification, venous malformation is a non-neoplastic developmental vascular disorder with multiple venous dilatations and low or slow flow [2]. It may occur on its own or combined with other types of vascular anomalies. It may be seen in various anatomical locations, such as cutaneous tissue, muscles and visceral organs, and most frequently in the head and neck. Breasts are an uncommon location. Few case reports have been reported for venous malformations in the breast and axillary region [3–8]. It may occur at any age [8,9].

Clinical Perspective

Venous malformation in the breast is usually asymptomatic. It may present with a painless palpable mass. It sometimes causes pain due to lesion thrombosis or haemorrhage. Focal bluish discolouration of the overlying skin may be present [2]. The diameter of vessels in the lesion typically increases with the Valsalva maneuver. These lesions are typically soft, compressible, and non-pulsatile [2]. They may be associated with syndromes such as Klippel–Trénaunay syndrome and Maffucci syndrome [1].

Imaging Perspective

Serpiginous tubular opacities on mammography and on ultrasonography are the most common imaging findings. Phleboliths can also be seen in the lesion, which are pathognomic [8]. Low-velocity monophasic flow on Doppler ultrasound can be demonstrated [8]. MRI can be helpful in making the diagnosis of venous malformations, which are hypo to isointense on T1W sequences and hyperintense on T2W sequences [10]. They show mild or marked contrast enhancement on post-contrast sequences. The presence of phleboliths, haemosiderin or thrombus may show blooming artefact on gradient echo sequences [11]. Slow flow can also be demonstrated on MRI. Detection of high-flow velocity of vessels may indicate an alternative diagnosis, such as an arteriovenous malformation or haemangioma.

Outcome

The correct diagnosis of these lesions is important as biopsies should be avoided because of the risk of bleeding. Depending on the presence of symptoms, location and extension of the lesion, treatment options are varied. Medical treatment usually depends on the presence of pain or thrombosis [12]. Compression treatment could represent an option. Sclerotherapy is a common treatment option. Surgical excision can be performed initially or after sclerotherapy [12].

Take Home Message / Teaching Points

Venous malformation in the breast is a rare entity. Phleboliths are pathognomonic for this entity. A correct diagnosis of these lesions is important as unnecessary biopsies should be avoided for the risk of bleeding. Radiologists should be aware of this entity and consider it in the differential diagnosis of breast lesions.