There are some further breakdowns that would be helpful but aren’t currently collected in the data, for example data below the main types of tumour (tumour sub-site).
Mae rhai dadansoddiadau pellach a fyddai'n ddefnyddiol ond nad ydynt yn cael eu casglu yn y data ar hyn o bryd, er enghraifft, data islaw’r prif fathau o diwmor (is-safle'r tiwmor).