Fine-needle Aspiration Cytologic Diagnosis of Lymphoepithelioma-like Carcinoma of the Lung:Report of Two Cases With Immunohistochemical Study

Abstract

Lymphoepithelioma is a term used to describe an undifferentiated carcinoma with prominent lymphoid infiltration in the nasopharynx. Recently, tumors with similar histology, designated as lymphoepithelioma-like carcinomas, have been described in other sites including the lung. The authors report two cases of pulmonary lymphoepithelioma-like carcinoma that were correctly diagnosed by fine-needle aspiration cytology. The distinctive cytologic features consist of cohesive sheets and clusters of spindle tumor cells, which possess moderately pleomorphic vesicular nuclei and prominent nucleoli that are intimately intermixed with numerous small lymphocytes. Immunohistochemical study, performed on the cell block preparation, revealed strong positive staining of these tumor cells for epithelial markers. In both cases, the cytologic diagnosis were confirmed subsequently by histologic examination of the resected surgical specimens. Cytologically, the differential diagnoses include granulomatous inflammatory diseases (especially tuberculosis), malignant lymphoma, melanoma, and metastatic sarcoma. The characteristic cytology of the tumor cells, together with their pattern of immunohistochemical staining, are helpful to distinguish lymphoepithelioma-like carcinoma from the differential diagnoses. In these cases, careful examination of the nasopharynx, preferably with multiple random mucosal biopsies, is essential for the exclusion of nasopharyngeal undifferentiated carcinoma because of the obvious differences in treatment and prognosis.

Cytological features of lung adenocarcinoma with massive lymphocyte infiltration

“…The cytological features of lymphoepithelioma-like carcinoma of the lung have been reported as showing evident signs of malignancy. [34] In contrast, well differentiated morphology with massive lymphocyte infiltration, as seen in the present case, may be scarce. This entity should be considered when evaluating pulmonary lesions with abundant lymphocytes.…”

Lymphoepithelioma-Like Carcinoma of the Breast: Cytological and Histological Features and Review of the Literature

“…There are a few reports about cytological presentation of these tumours in the nasopharynx, lungs and salivary glands [11,12,13]. Recently, cytomorphology of LELC of the urinary bladder has been described [14,15].…”

Giant Cell Carcinoma of the Lung

“…The background material also is rich in lymphocytes, polymorphic leukocytes and naked vesicular nuclei. 14 Careful examination of the nasopharynx is required to exclude a nasopharyngeal undifferentiated carcinoma metastatic to the lung. Another neoplasm that must be distinguished is amelanotic malignant melanoma, the cytohistologic resemblance to which may be a challenge.…”