Cancer Surgery and Marriage
If a man undergoes an orchiectomy due to cancer or some other medical reason, is that man able to get married in the Catholic Church?
In canon law, perpetual impotence is an impediment to marriage (can. 1084 §1) but infertility is not (can. 1084 §3).
The resulting infertility of the surgery would not prevent the marriage from taking place.
If the surgery resulted in perpetual impotence, then the marriage would not be able to take place. The impotence must be prior to the exchange of vows and be a truly permanent condition. If the surgery only rendered engaging in the marital act difficult but not impossible (within moral means), then the upcoming marriage would not face any canonical impediments.