Our present study based on KEGG pathway analysis showed that the genes upregulated in SCLC tissues were associated with the “cell cycle”, “Fanconi anemia”, “alcoholism”, “systemic lupus erythematosus”, “oocyte meiosis”, “homologous recombination”, “DNA replication”, and “p53 signaling” pathways. This evidence concerns the gene TP53 and Fanconi anemia.