Lymphoepithelioma-like carcinoma of the breast

Abstract

Lymphoepithelioma-like carcinoma of the breast is a rare malignancy, with fewer than 20 cases documented in the literature. Given the paucity of reported cases, there is limited information available to guide the diagnosis and management of patients with this tumor. We present a case of a 39-year-old woman with a palpable right breast mass that was initially diagnosed by core needle biopsy as infiltrating carcinoma with prominent lymphoplasmacytic stroma. Subsequent neoadjuvant chemotherapy with docetaxel, doxorubicin, and cyclophosphamide resulted in a marked decrease in the size of the mass. After wide local surgical excision, pathology revealed a lymphoepithelioma-like carcinoma of the breast. Given the excellent treatment response, our experience may help clinicians determine future therapeutic strategies for this rare breast tumor.

Fig. 1

39-year-old female with lymphoepithelioma-like carcinoma of the right breast. Right mediolateral-oblique (A), craniocaudal (B), and spot magnification craniocaudal (C) digital mammographic projections demonstrate a 2.7-cm, irregular-shaped, high-density mass with microlobulated margins located at the 1 o'clock position at mid depth. Metallic BB markers overlie the nipple and the palpable mass on the mediolateral-oblique and craniocaudal projections.

Fig. 2

39-year-old female with lymphoepithelioma-like carcinoma of the right breast. Ultrasound images in transverse (A) and longitudinal (B) orientations show a 2.7 × 2.5 × 2.5-cm, nonparallel, irregular-shaped, hypoechoic mass with heterogeneous internal echogenicity, microlobulated margins, and posterior acoustic enhancement. The mass is located at the 1 o'clock position and corresponds to the mammographic mass.

Fig. 3

39-year-old female with lymphoepithelioma-like carcinoma of the right breast. Contrast-enhanced computed tomography axial (A), coronal reformatted (B), and sagittal reformatted (C) images demonstrate an irregular-shaped soft-tissue-density mass with heterogeneous internal enhancement in the right breast upper inner quadrant.

Fig. 4

39-year-old female with lymphoepithelioma-like carcinoma of the right breast. Ultrasound images in transverse (A) and longitudinal (B) orientations after administration of six cycles of neoadjuvant chemotherapy demonstrate only a small residual area of hypoechogenicity at the site of the primary tumor at the 1 o'clock location (white arrows), indicating an excellent treatment response. An echogenic focus representing the microclip placed at the time of core needle biopsy is also noted (black arrowheads).

Fig. 5

39-year-old female with lymphoepithelioma-like carcinoma of the right breast. Photomicrograph of tissue samples from the wide local excision specimen. Hematoxylin and eosin stain, 20X (A) demonstrates cords of undifferentiated neoplastic cells (arrow) with a prominent lymphocytic stromal infiltrate. Hematoxylin and eosin stain; 40X (B) shows large tumor cells (arrow) with poorly defined cytoplasmic borders, pleomorphic and vesicular nuclei, and nucleoli. Lymphocytic infiltrate is present throughout the tumor. A mitotic figure can be seen in the center of this image (arrowhead). Staining with CAM 5.2; 20X (C) shows neoplastic cells positive for the CAM 5.2 keratin marker. CD3 immunohistochemistry staining; 20X (D) demonstrates infiltrating lymphocytes highlighted by the CD3 marker.