Primary breast angiosarcomas are rare with an incidence rate of 0.04% of all malignant breast tumors [3,4,5]. They have no known risk factors. Some articles mentioned that they might be associated with pregnancy while others stated that there was no solid evidence to suggest that these tumors were hormone-dependent [3, 5, 6]. They normally occur in younger age groups with the mean average age of 30–40 [4, 5]. Our patient, aged 35 was within the average age group, however was neither pregnant nor on hormonal treatment. She had no known risk factors or previous medical illness.
The clinical presentation of primary angiosarcomas can be varied; however, most present as a fast-growing palpable mass with overlying skin changes [1, 5, 7]. In our case, the initial history given was a gradual swelling of the left breast after a fall with trauma to the breast, leading the clinicians to suspect a hematoma, thus resulting in a wrong and delayed diagnosis. She also had bruises on other parts of the body, further confusing the diagnosis. Eventually after further probing, we managed to find out that the lump was actually palpable prior to the fall, which then pointed the diagnosis more towards a vascular tumor instead of purely a hematoma. Initial blood investigation showed thrombocytopenia (platelet reading was 66 with the unit of 109/L) and coagulopathy which was consistent with Kasabach-Merritt syndrome as reported by several journals [7].
The diagnosis of angiosarcomas can be challenging as most of them have non-specific radiological findings. On ultrasound, these tumors may present as hypo-, hyper-, or heterogeneous masses which are highly vascular in nature. Mammographically, the findings are very non-specific with up to 33% of these tumors presenting as normal mammograms as reported by Liberman [5, 6, 8]. MRI is a more promising and supportive imaging modality which demonstrates low T1 signal and markedly high T2 signal. On dynamic phase, these tumors normally demonstrate rapid wash in followed by either prolonged enhancement or rapid wash out. In our case, the patient’s ultrasound showed a large ill-defined heterogeneous mass with mixed solid and cystic components within, occupying almost the entire left breast. It had multiple large vessels within the mass. However, no significant left axillary lymphadenopathy was detected. Even though mammogram was not performed in this patient due to severe pain, an MRI scan was performed to further assess this mass. On MRI, the mass demonstrated predominantly low T1 signal, extremely high T2 signal with rapid wash in and prolonged enhancement on dynamic phase. Overall, even though the radiological findings from our patient’s ultrasound and MRI may not have specific diagnostic features for angiosarcoma, it did help to characterize the mass, hence leading to the correct diagnosis.
There were journals which stated that fine-needle aspiration cytology and core biopsy are generally not helpful in the diagnosis of angiosarcoma as they give high false-negatives, as high as 37% [4, 6, 9]. This did apply in our case, where the result of the core biopsy taken by the surgical team was inconclusive with blood clots seen as the mass was highly vascular and hemorrhagic, making diagnosis difficult. No strict contraindication for biopsy was previously mentioned by any journals, but it would be helpful for the biopsy to be done under ultrasound guidance in order to obtain proper samples and in avoiding the major vessels within the mass, hence reducing the difficulty in securing hemostasis, which happened in our case.
Histologically, angiosarcomas of the breast can be classified into grades 1, 2, and 3 or low, intermediate, and high. The cells are spindle shaped with large, oval nuclei, and vesicular chromatin. There are also large anastomosing vascular channels within. The high-grade tumors always demonstrated areas of ‘blood lakes’ which meant that there was bleeding into the surrounding stroma, as seen in our patient. Immunohistochemical staining-like factor VIII and CD31 plays an important role in differentiating angiosarcomas from other vascular tumors. Our patient’s diagnosis was confirmed after proper microscopic examination together with immunohistochemical staining of the excised breast tissue.
The gold standard treatment for primary breast angiosarcomas is still surgery which includes total mastectomy or wide local excision, with or without axillary clearance. Total mastectomy is more favorable than wide local excision because of the resection margin status, as well as the high incidence of local recurrence in wide local excision as documented in most articles [3, 7]. Regional axillary clearance is not necessary because they tend to metastasize hematogenously, rather than lymphogenously [3, 4, 7, 9]. Our patient underwent total mastectomy with regional axillary clearance; however, she still developed local recurrence 6 months later.
The role of chemotherapy and radiotherapy in breast angiosarcomas is still not well established. However, some articles have reported that chemotherapy may be more effective in high grade tumors and in metastatic setting [1, 3,4,5, 7, 9]. Few small sample studies also documented positive outcomes for both conservative surgery or post-mastectomy radiation [5, 9]. Most authors believe that both the chemotherapy and radiation therapy may reduce the rate of local recurrence and hence improve the total survival rate. Our patient received 6 cycles of chemotherapy with the drug Paclitaxel three weekly followed by adjuvant radiotherapy in the later part of her treatment.
Angiosarcomas of the breast are generally known to be poor in prognosis, especially for tumors more than 5 cm in size as well as for patients with distant metastasis at the time of diagnosis. A study done by Rosen et al. showed that the 5-year disease-free survival in high grade tumors was only 15% [1, 5, 6, 9]. Up to date, many debates are still going on regarding the prognostic factors and these include tumor size, surgical tumor margin status, and tumor grading. Our patient’s tumors were more than 5 cm at the time of diagnosis with high tumor grading and these gave her poorer prognosis. Otherwise, no distant metastasis was seen. She was doing well in the first 6 months after surgery. Unfortunately, she returned with recurrence 6 months later.