Epidermal growth factor receptor (EGFR) mutations in small cell lung cancers: Two cases and a review of the literature

• We report a case of SCLC harboring a novel D855H point mutation in the EGFR gene.
• We report a case of SCLC demonstrating a L858R point mutation in the EGFR gene.
• We review the literature and note 59 reported SCLCs with EGFR mutations.
• Only 4 EGFR mutations would not have been identified based on recent Guidelines.
• These findings support the Guideline recommendations for EGFR testing in SCLC.

Activating mutations in the epidermal growth factor receptor (EGFR) gene are exceedingly rare in small cell lung cancer (SCLC). We present two cases of SCLC harboring EGFR mutations, one in an 82 year-old male smoker with a combined SCLC and adenocarcinoma with a novel D855H point mutation in exon 21, and the second in a 68 year-old female never smoker with the L858R point mutation in exon 21. The cases, accompanied by a review of the literature, highlight the importance of integration of clinicopathologic considerations and adherence to recently promulgated Guideline recommendations for molecular testing in lung cancer.