The lymphoma risk is pretty low, and it is more in regard to those with rheumatoid arthritis (who are already at a higher risk). Using it in combination with other immune modulators increases the risk, particularly over a long period of time. Yes, the risk is higher in the pediatric and adolescent population, but it is still quite low. The fact that he would be only using this short term means that the safety profile is much greater than those who are anticipating long term maintenance use.
It can take up to three months for any of the biologics to have a full effect. After that time period, if there is no response, there is no point in continuing. I am presuming that topical steroids are not effective?
In my mind, the bigger question would be the possible increased risk of post op sepsis while using this drug in the immediate pre op period. I would rather just do the completion proctectomy and j-pouch procedure without it. There are risks any way you slice it, and since this is not about preserving the colon or rectum, if it were my son, I would want some compelling reason to consider it at this point.
My two cents, but I think you need a lot more information and convincing from his doctors, besides just a recommendation. I am not sure where they get the 50% healing notion in order to do the surgery. Being refractory to treatment is the reason for the surgery!
Jan