EGFR and adenocarcinoma: In the setting of fully excised lung cancer specimens, EGFR testing is not recommended in lung cancers that lack any adenocarcinoma component, such as pure SqCC and pure small cell carcinomas.16 However, in the setting of small lung biopsies, adenosquamous carcinoma could be misdiagnosed as SqCC or NSCLC favor SqCC due to undersampling.