Synchronous nasal metastasis from pulmonary squamous cell carcinoma

Introduction: Squamous cell carcinoma spread from lung to the nasal cavity is extremely rare. Because of the identical appearance under light microscope, making a definitive diagnosis is a challenge when lesions are from both the nasal cavity and lung. Case report: We present a case of a 56­year­old patient with simultaneous malignancies in the lung and nasal cavity. On the basis of histologic analysis and radiographic features, a diagnosis of primary lung cancer with nasal metastsis was established. Since the histological appearance of the lung tumor and the nasal lesion is similar, the differential diagnosis between second primary and metastasis mainly depends on clinical criteria. However, the accuracy of this approach remains in question. Conclusion: It is a challenge to discern the true relationship of lung squamous cell carcinomas and nasal squamous cell carcinomas. The criteria currently employed in the distinction are mainly dependent on clinical, radiographic, and histologic grounds. Recent studies demonstrated that molecular genetic analysis can be a promising approach to solving this diagnosis dilemma.