My Son Had Carcinoid Cancer In The Left Lung .

My son had carcinoid cancer in the left lung . He had a left lower lobe removed. The surgery was the end of august 2016. A couple of weeks ago he woke up with a itchy rash that sent him to the walk in clinic. Over the last twenty four hours he had a bad case of stomach flu followed by another bout of itchy rash which send him back to the clinic. My question is could any of this be related to the surgery?