Primary Breast Carcinoma of the Vulva Metastatic to Lymph Nodes and Bones: A Case Report and Literature Review.

Introduction: Primary breast carcinoma can occur at ectopic sites. The axilla is the most common site of ectopic primary breast cancer, but presentation in the vulva is rare. We discuss a rare presentation of primary breast carcinoma of the vulva with distant lymph node and bone metastases in a premenopausal woman.

Case Presentation: A vulvar malignancy consistent with adenocarcinoma of the mammary gland type was diagnosed in a 47-year-old premenopausal woman. The patient underwent radical vulvectomy with bilateral superficial and deep inguinal lymphadenectomy. The tumor was positive for estrogen receptor and negative for progesterone receptor and human epidermal growth factor receptor 2/neu on immunohistochemical findings. A positron emission tomography-computed tomography scan demonstrated lymph node and bone metastases. Her disease was treated as stage IV breast cancer with metastases to the bone. Palliative treatment with ovarian suppression, aromatase inhibitor, and cyclin-dependent kinase 4/6 inhibitor was recommended.

Discussion: For a diagnosis of primary breast cancer of the vulva, a thorough metastatic workup should be performed, with attention directed toward detecting a breast primary disease by results of the history, physical examination, and radiologic examination of the breasts mainly to help confirm that the vulvar lesion is the primary site as opposed to metastasis from a breast primary cancer and also for staging. Management of this rare entity is challenging because of a lack of specific guidelines, and treatment, therefore, is similar to that of breast cancer.Treatment should consist of an individualized combination of surgery, radiotherapy, chemotherapy, and antiestrogen hormonal therapy.