Unknown Case: Spontaneous Breast Bruising

An 86-year-old woman with a remote history of left breast cancer status post-lumpectomy, hormonal therapy, and radiation therapy presented with spontaneous bruising of the left breast (Figure 1), skin thickening, and sensation of breast fullness. The patient denies history of nipple discharge but has mild tenderness to the left breast on physical exam. The patient does not recall a history of recent trauma and is not on blood thinners. Clinical photograph demonstrates skin thickening with localized blue and purple skin color change. Mammography demonstrates a round mass with circumscribed margins at the 2 o’clock position and an oval mass with indistinct margins at the 10 o’clock position (Figure 2). US shows a mass with indistinct borders and heterogeneous echo pattern at the 2 o’clock position (Figure 3). No sonographic correlate is seen for the 10 o’clock position mass. MRI demonstrates an oval mass with circumscribed margins at the 2 o’clock position that is T2 hyperintense and demonstrates rim and heterogeneous mass enhancement on postcontrast T1 images (Figure 4). At the 10 o’clock position is an irregular mass with heterogeneous enhancement on postcontrast T1 weighted imaging (Figure 4). This mass shows mild T2 hyperintensity. Left mammogram demonstrates a skin marker (dashed arrow) projecting over the region of bruising noted by the patient. In the 2 o’clock position, there is a new round mass (arrowhead) with circumscribed margins. At the 10 o’clock position, there is an oval mass (arrow) with indistinct margins. US of the left breast at the 2 o’clock position shows an irregular mass with indistinct margins and heterogeneous echo pattern. At the 10 o’clock position, no sonographic correlate was identified. Axial fat-saturated T2 weighted image (A) shows a T2 hyperintense oval mass at the 2 o’clock position with circumscribed margins. T1 axial postcontrast image of the 2 o’clock position (B) demonstrates heterogeneous and rim enhancement. T1 axial postcontrast of the 10 o’clock position (C) demonstrates an irregular mass with heterogeneous enhancement. 3D maximum intensity projection (D) demonstrates the 2 o’clock and 10 o’clock position masses as well as two areas of focal skin enhancement. The differential considerations include ipsilateral breast tumor recurrence, secondary angiosarcoma, trauma/hematoma, inflammatory breast cancer, and metastasis. In isolation, skin thickening and tenderness of the breast after radiation therapy do not carry a high index of suspicion for breast cancer. New skin changes, new palpable masses, or new breast bruising, however, should raise concern. In this clinical setting, the presentation of new breast bruising and skin thickening after a multiyear latency from breast conservation therapy raises concern for ipsilateral breast tumor recurrence and angiosarcoma above others on the differential. On further review, no trauma history or reason for spontaneous bruising was found to support hematoma or fat necrosis, nor did the patient have a history of alternative diagnosis to suggest metastatic disease. Inflammatory breast cancer classically appears as edema, erythema, and tenderness of the breast, which can clinically mimic mastitis, as opposed to purple skin discoloration seen in this case. The US and mammogram findings are highly suggestive of malignancy but not specific. The MRI, however, shows characteristics of angiosarcoma detailed in the literature including masses showing high signal intensity on T2-weighted images with rapid enhancement of the masses and skin enhancement. These findings, in combination with the clinical history, prioritize angiosarcoma as the most likely diagnosis. This patient went on to radical mastectomy, with surgical pathology showing multicentric angiosarcoma of the breast. Secondary or radiation-associated angiosarcoma (RAS) of the breast is a malignant tumor that arises from endothelial cells that line the vascular channels of the breast (1). Secondary angiosarcoma of the breast arises in older patients, mean age 65 (1,2), who have undergone prior breast conservation therapy (lumpectomy and radiation) (1,2) or who suffer from lymphedema post-mastectomy (Stewart-Treves syndrome) (3). The mean latency period for appearance of RAS after radiation therapy is between 5 and 7 years (1). The incidence rates for RAS after breast irradiation are estimated to be between 0.09% and 0.16% (2). Radiation-associated angiosarcoma does not have a specific mammographic appearance. Findings are often obscured or similar to post-treatment changes and include the presence of skin thickening, noncalcified masses, or focal asymmetry (1,4). Sonographic findings are similarly nonspecific. Independently, skin thickening, irregular margins, hypoechoic masses, posterior acoustic shadowing, and increased through transmission have all been described (1,3,5). On MRI, RAS is associated with T2 hyperintense skin thickening (1,5). Both high (2,4) and low (1,5) signal intensity of lesions on T2 images have been characterized. Irregular areas of high T1 signal may be seen within high-grade lesions, which represents either hemorrhage or venous lakes (2,3). Lastly, rapid initial and delayed phase washout kinetics of lesions have been described (1,5). Overall, radiation associated angiosarcoma is known to have high rates of local recurrence and metastasis, making for a relatively poor prognosis. The five-year overall survival rate is 10% to 54% (1). Treatment primarily involves surgical resection with negative margins (6). Institutional review board exemption and direct patient consent were obtained prior to the preparation of this submission. None declared.