This dataset contains information on alternative splicing isoform switches as described in the related paper "Alternative splicing changes as drivers of cancer" (pre-print available). It contains the list of the observed switches, altogether with their functional implications (effect on the protein, on the PPI network, etc.) and related measures of relevance (links to mutational data, etc.). This dataset was thoroughly explored in a related Jupyter notebook. H.C-G and E.E. were supported by the MINECO and FEDER (BIO2014-52566-R), Consolider RNAREG (CSD2009-00080), AGAUR (SGR2014-1121), and the Sandra Ibarra Foundation for Cancer (FSI2013). E.P-P and A.G. were supported by the SBP CC grant (P30 CA030199). All authors thank The Cancer Genome Atlas project for making their data publicly available.