Combined with our previously studied genomic profiles of SCCE, we found that genes such as CCNE1, PTEN and PIK3R1 and pathways such as the cell cycle pathway, the P53 pathway and the Wnt signalling pathway are deregulated at both the genome and transcriptome levels, suggesting their crucial roles in the initiation and progression of SCCE. This evidence concerns the gene PIK3R1 and cervical small cell carcinoma.