Bruce Willis diagnosed with frontotemporal dementia, his family says

• “While this is painful, it is a relief to finally have a clear diagnosis,” the family's statement read. “FTD is a cruel disease that many of us have never heard of and can strike anyone.”

Context: FTD represents a group of brain disorders that affect the patient's frontal and temporal lobes, according to the Association for Frontotemporal Dementia.

• It is the most common form of dementia for people under age 60, per the AFD.

Signs and symptoms may vary. Some develop significant changes in their personalities and become "socially inappropriate," while others may lose the proper use of language, according to the Mayo Clinic.

• Willis' family said one major symptom for the actor has been communication challenges.
• FTD does not have any specific treatment, per the Mayo Clinic.

Willis' career spans over 40 years and his movies had earned more than $5 billion at the box office, AP reports. His biggest projects include the "Die Hard" franchise and "The Sixth Sense."