diabetes 6 months after surgery

hi 

my husband had sepsis in early May last year   which left him with multiple liver abscesses   a renal vein blood clot and an enlarged pancreatic duct

he took 6 - 8 weeks to fully recover     then had months of tests to see if the source of infection could be found 

eventually he had an endoscopy that still didn't show anything    but they took random biopsies anyway      which did show up an early pancreatic cancer   

this was followed up by him having a distal pancreatectomy and spleen removal on 25 th Sept 2019      Unfortunately after a long op    he had an internal bleed immediately after hisnoperatiom

and had to rerun to theatre for a second time in the same day     He made a good recovery and was discharged home only a week later     

One of his drains were still in at discharge and  got infected      day 13 he ended up back into to hospital for a further weeks iv antibiotics

his main wound also had infection building up behind it     so needed to be opened up again  to allow the pus the ooze out 

he has eventually recovered   after weeks of his wound leaking  pancreatic juices -  which isn't that uncommon were told 

due to his wound infection he missed his  12 week post surgery appointment with oncologist to organise chemo   so didn't end up getting any     He has no spread to lymph nodes or elsewhere so it was thought to be safe 

last week it was time for his check up but due to coronavirus it was cancelled      instead had a consultation over the phone with consultant instead     having periods of fatigue and thirst    so he suggested blood checks getting done    which has shown he has diabetes      and needed to start insulin today      

are there any others who developed diabetes 6 months post op       

Do you think this mean his cancer is back as his pancreas isn't making insulin any more ? 

l