Hi Mignon,
My sister Susan has SLE and the link with cancer is mainly due to autoimmune suppressants, Im not sure which drugs though. However DNA predisposition does play another large part too.
(Our Dad was builder/carpenter in 1960/70 and used all chemicals spraying timber which I believe altered his DNA, hence Lupus and Kidney Cancer, there is no link to either dis-ease in maternal and paternal ancestory).
Australia has foundations in all states however America's John Hopkins Centre for Lupus is very well educated and written, this will give more of an insight into drugs....however my opinion only....with a compressed immune system which cant control inflammation, any damage to tissue will encourage the growth of damaged cells which we know as tumors (cancerous or benign). Maybe send a message to ccadmin, Felix and Kate are fantastic with these questions. Julesx