Distant Lung Metastasis of Basal Cell Carcinoma; A Case Report and Review of Literature

Abstract

Background: Basal cell carcinoma (BCC) is the most common non-melanoma cutaneous neoplasm. It is a locally invasive malignant tumor that exhibits an extremely limited potential for distant metastasis. There are several histological variants of basal cell carcinoma, which differ significantly in their microscopic features, clinical behavior, and prognosis.

Case Presentation: A 72-year-old man presented with a history of a left cheek nodular basal cell carcinoma that had been previously resected with free margins. Four years later, the patient complained of difficulty breathing. Radiological evaluation revealed pleural thickening and multiple pulmonary nodules. Histopathological examination of an incisional core biopsy demonstrated a neoplastic proliferation of atypical epithelial cells arranged in sheets and nests within a dense desmoplastic stroma. These tumor nests exhibited prominent peripheral cellular palisading with central, haphazardly arranged primitive cells, alongside scattered foci of squamous differentiation. Consequently, a diagnosis of metastatic basal cell carcinoma was established.

Conclusion: Although basal cell carcinoma is a locally aggressive cutaneous neoplasm with an extremely low metastatic potential, factors such as a large primary tumor size and the presence of occult aggressive variants may significantly augment its metastatic capability.