Primary Giant Cell Tumor of the Breast With Pulmonary Metastasis: A Case Report and Review of the Literature

Abstract

Giant cell tumor of soft tissue (GCT-ST) is an extremely rare tumor that is similar in morphology and immunohistochemistry to giant cell tumor of the bone. Almost 80% of these tumors occur in the upper and lower extremities, and the breast is a very rare location. Here, we report a case of a 65-year-old female patient with a small mobile palpable lump in the left breast. Although the left breast tumor was considered malignant on preoperative imaging, no evidence of malignant tumor was found by ultrasound-guided core needle biopsy (CNB). Subsequently, the left breast tumor was confirmed as a malignant tumor by intraoperative rapid pathological examination. The initial treatment of the tumor was wide local excision and sentinel lymph node biopsy, and it was confirmed to be GCT-ST by histopathology and immunohistochemistry. Despite surgical treatment achieving clear surgical margins, the patient experienced lung metastases within a year of her initial treatment. Fortunately, the patient underwent surgical treatment of lung metastases, and at the last follow-up, the patient was still alive. This is the first case of a primary soft tissue tumor of the breast that has undergone surgical intervention after lung metastasis. This case report highlights the complexity of the clinical diagnosis and treatment of GCT-ST arising from the breast. Surgery may be another good treatment when the patient develops lung metastases.

Keywords: breast tumor; diagnosis; giant cell tumor of soft tissue; prognosis; treatment.

Figure 1

(A) Ultrasonographic image showing a low echo mass in the upper inner quadrant of the left breast and with an irregular shape and uneven internal echogenicity. (B, C) Color-flow Doppler image showing small amount of blood flow signals inside and vessels in rim. (D) No enlarged lymph nodes were found in the armpit.

Figure 2

(A–C) Axial and sagittal contrast-enhanced MR image shows rapid and heterogeneous tumor enhancement. (D) Dynamic contrast-enhanced magnetic resonance imaging (MRI) demonstrated a time–signal intensity curve (TIC) with a rapid rise to a peak (after the administration of the contrast material), followed by a slow-out at the mass.

Figure 3

Histopathology of primary tumor. (A) Hematoxylin and eosin staining (magnification: ×100); (B) immunohistochemistry for CD68 (magnification: ×100); (C) immunohistochemistry for CD163 (magnification: ×100); (D) immunohistochemistry for PR (magnification: ×100); (E) immunohistochemistry for ER (magnification: ×100); (F) immunohistochemistry for KI-67 (magnification: ×100).

Figure 4

Chest CT showed that a soft tissue nodule in the left upper lobe with lobulated contours, inhomogeneous density, and calcifications is visible inside, and the largest cross-sectional dimension of the mass was 1.0 cm × 1.1 cm.

Figure 5

Histopathology of metastatic lesion. (A) Hematoxylin and eosin staining (magnification: ×100); (B) immunohistochemistry for CD68 (magnification: ×100); (C) immunohistochemistry for CD163 (magnification: ×100); (D) immunohistochemistry for S-100 (magnification: ×100).