Morning
So sorry to read about your dad and see you joining us here 
Assume the chemo for asbestos related cancer is Mesothelioma ?
This swelling may be chemo related but more likely is something to do with the many lymph nodes in and around the groin area so chances are this could be where the swelling is ? Has anyone asked for advice from his 'onco team' about this swelling as any change should be mentioned ?
As most here are either patients or carers the best place for this question would be in the 'Ask a Nurse' area here.
There area couple of groups you could join that may be of help - One is the Carers Group and there is also a Mesothelioma Group where you could get answers to chemo related questions.
Hope you dad isn't suffering too much with chemo side effects and this is of some help for now.
Hugs, G n' J
