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Distinction of histologically heterogenous, single primary tumor from two or more collision tumors with different primaries could represent a challenge to practicing pathologists. Histologic variations including differences in degree of differentiating within a tumor, are typically interpreted as tumor heterogeneity in a contiguous small size tumor biopsy. The authors report a case of adult former smoker female who presented with lung mass and a metastatic lytic lesion of acetabulum. A needle biopsy of a lung mass revealed an adenocarcinoma with well and moderately differentiated components. Next generation sequencing studies proved 2 different primaries in this small needle biopsy.