538 - BREAST LIPOSARCOMA

Resumo

Breast sarcomas are a heterogenous group of malignancies that originate from the breast support stroma. They represent
less than 0.1% of all breast neoplasms and less than 5% of all sarcomas. They are more frequent in women and between the
fourth and sixth decades. Previous breast cancer treatment and radiotherapy are the main risk factors. The usual clinical
presentation is a breast mass, which grows progressively and can reach a large size. They rarely attach themselves to the
thorax or infiltrate the skin. Skin changes, when occur, are usually secondary to a large distitute. The tumor is usually well
or partially defined, with a firm consistency. Lymph nodes are palpable in up to 25% of cases but tend to be reactional.
Imaging findings are nonspecific. For histopathological diagnosis, it is necessary to exclude metaplastic carcinoma, and
immunohistochemistry is useful to detect evidence of epithelial origin. Treatment requires resection with wide margins,
and mastectomy may be necessary. Hematogenous dissemination occurs, and lymph node interventions should only be
performed in the presence of a proven histopathological impairment. There is a trend of improvement in survival with
radiotherapy after conservative surgery. After mastectomy, radiotherapy may be beneficial in cases of increased risk of
local recurrence (lesions larger than 50 mm, unsuitable margins, and higher grade variants). The role of chemotherapy
remains controversial. Liposarcoma, a histological subtype of sarcoma, despite being the second most frequent subtype
in soft tissues, rarely occurs in the breast. Liposarcoma encompasses a spectrum, from lesions with essentially benign
behavior to frankly malign lesions. Liposarcomas classified as myxoid, pleomorphic, and dedifferentiated have a higher
risk of recurrence and metastases. The main differential diagnoses of breast liposarcoma include other breast tumors
with lipomatous or liposarcomatous components, fat necrosis, and metaplastic carcinoma. CSSP, 48 years old, female,
attended the Mastology Service of the Central Hospital of the Army, referring a breast nodule for 2 months with growth
in the period. On clinical examination, a well-defined, mobile oval nodule with firm consistency was observed, measuring 40 mm, with no associated findings. At mammography and ultrasonography, the nodule was oval and circumscribed.
Magnetic resonance imaging showed heterogeneous enhancement and a type II curve. A simple mastectomy was performed due to the poor tumor-breast relationship, with a histopathological result of dedifferentiated liposarcoma with
areas of myxoid pattern, measuring 40 mm, and free histopathological margins. Adjuvant radiotherapy was indicated
due to the diagnosis of dedifferentiated liposarcoma with areas of myxoid pattern.