Atypical vascular lesions (AVLs) of the breast are rare cutaneous vascular proliferations that present as erythematous, violaceous, or flesh-colored papules, patches, or plaques in women who have undergone radiation treatment for breast carcinoma.1,2 These lesions most commonly develop in the irradiated area within 3 to 6 years following radiation treatment.3
Various terms have been used to describe AVLs in the literature, including atypical hemangiomas, benign lymphangiomatous papules, benign lymphangioendotheliomas, lymphangioma circumscriptum, and acquired progressive lymphangiomas, suggesting benign behavior.4-10 However, their identity as benign lesions has been a source of controversy, with some investigators proposing that AVLs may be a precursor lesion to postirradiation angiosarcoma.2 Research has addressed if there are markers that can predict AVL types that are more likely to develop into angiosarcomas.1 Although most clinicians treat AVLs with complete excision, there currently are no specific guidelines to direct this practice.
We report the case of a patient with a history of 1 AVL that was excised who developed 3 additional AVLs in the same breast over the course of 15 months.
Case Report
A 55-year-old woman with a history of obesity, hypertension, and infiltrating ductal carcinoma in situ of the right breast (grade 2, estrogen receptor and progesterone receptor positive) underwent a right breast lumpectomy and sentinel lymph node dissection. Three months later, she underwent re-excision for positive margins and started adjuvant hormonal therapy with tamoxifen. One month later, she began external beam radiation therapy and received a total dose of 6040 cGy over the course of 9 weeks (34 total treatments).
The patient presented to an outside dermatology clinic 2 years after completing external beam radiation therapy for evaluation of a new pink nodule on the right mid breast. The nodule was biopsied and discovered to be an AVL. Pathology showed an anastomosing proliferation of thin-walled vascular channels mainly located in the superficial dermis with notable endothelial nuclear atypia and hyperchromasia. There were several tiny foci with the beginnings of multilayering with prominent endothelial atypia (Figure 1). She underwent complete excision for this AVL with negative margins.
Figure 1. Histopathology of an atypical vascular lesion demonstrated a relatively circumscribed, abnormal, anastomosing proliferation of thin-walled vascular channels located predominantly in the superficial dermis with the endothelial nuclear atypia and hyperchromasia; several tiny foci with the beginnings of multilayering with prominent endothelial atypia also were present (H&E, original magnification ×40).
Six months after the initial AVL diagnosis, she presented to our dermatology clinic with another asymptomatic red bump on the right breast. On physical examination, a 4-mm firm, erythematous, well-circumscribed papule was noted on the medial aspect of the right breast along with a similar-appearing 4-mm papule on the right lateral aspect of the right breast (Figure 2). The patient was unsure of the duration of the second lesion but felt that it had been present at least as long as the other lesion. Both lesions clinically resembled typical capillary hemangiomas. A 6-mm punch biopsy of the right medial breast was performed and revealed enlarged vessels and capillaries in the upper dermis lined by endothelial cells with focal prominent nuclei without necrosis, overt atypia, mitosis, or tufting (Figure 3). Immunostaining was positive for CD34, factor VIII antigen, podoplanin (D2-40), and CD31, and negative for cytokeratin 7 and pankeratin. This staining was compatible with a lymphatic-type AVL.1 A diagnosis of AVL was made and complete excision with clear margins was performed. At the time of this excision, a biopsy of the right lateral breast was performed revealing thin-walled, dilated vascular channels in the superficial dermis with architecturally atypical angulated outlines, mild endothelial nuclear atypia, and hyperchromasia without endothelial multilayering. Clear margins were noted on the biopsy, but the patient subsequently declined re-excision of this third AVL.
Figure 2. Linear scar at the 12-o’clock position denoted the first excised atypical vascular lesion. Three atypical vascular lesions were subsequently found (red arrows).
Figure 3. Histopathology of an atypical vascular lesion demonstrated enlarged vessels lined by endothelial cells in the upper dermis with focal prominent nuclei without necrosis, overt atypia, mitosis, or tufting (H&E, original magnification ×200).
During a subsequent follow-up visit 9 months later, the patient was noted to have a 2-mm red, vascular-appearing papule on the right upper medial breast (Figure 2). A 6-mm biopsy was performed and revealed thin-walled vascular channels in the superficial dermis with endothelial nuclear atypia consistent with an AVL.