How do you approach screening for additional malignancies in patients with a history of CTCL?

There is no need to do anything out of ordinary. Usual age-appropriate cancer screening and skin cancer screening (many of these patients received light and radiation therapy) is sufficient. The rest should be guided by presenting symptoms. For smokers and other people with specific risk factors, they should be followed by the respective specialists.

Agree with Dr. @Dr. First Last. I would recommend age-appropriate and risk-factor-associated cancer screening as directed by their primary care physician. Also, I encourage patients to get annual preventative health visits with their primary care physician. They may also be at higher risk of other skin cancers, given treatment history and skin type. Also, recall that some patients with mycosis fungoides may also be associated with other CTCL, such as LyP.