Distinguishing Head And Neck Cancer Metastasis From Second Primary Squamous Lung Cancer In The Genomic Era.

e17506Background: Patients with head and neck squamous cell carcinoma (HNSCC) are at risk for both lung metastases and secondary primary cancers of the lung. Given the histopathologic similarity between these two lesions, distinguishing metastasis from a second primary lung SCC is often based on clinical grounds. Resection of “oligometastatic” HNSCC lesions may be associated with favorable prognosis, although this remains controversial. We demonstrate the potential of a commercially available genomic platform to resolve this clinical dilemma. Methods: A 64-year-old 20 pack-year former smoking male with history of HPV-associated oropharyngeal (OP) cancer 4 years prior presented with an asymptomatic 4.5 cm right hilar mass on surveillance images. Following surgical resection, the patient was referred for adjuvant chemotherapy for pT2aN1 (stage IIB) presumed lung SCC. To settle concerns this was a late recurrence of HNSCC, the primary OP and resected lung tumors were subjected to histopathologic analysis, p1...