The summary says he went into a Rome hospital for what was expected to be a relatively simple procedure to remove the nodule. During the surgery, doctors removed it, examined it and found cancer.
That is a small but significant set of facts, and also a limited one. On the available sourcing, the reported diagnosis is early-stage lung adenocarcinoma following the nodule’s removal. The summary does not include a prognosis, any treatment plan beyond the surgery, or a formal statement from the Vatican or the treating doctors.
With only an RSS summary to work from, the cleanest version of the story is also the narrowest: a lung procedure became a cancer diagnosis in the operating room.
Dua Mifsud 
Sophia Borg 
Harvey Jr. 
Marcus Azzopardi