This research study will help us learn more about how chronic graft-versus-host disease affects the skin, hair and nails. We are interested in knowing if hair and nail problems predict worse disease. This information may help us treat patients like you in the future.

• At the initial visit, participants will have a complete examination of their skin, hair and nails. We will also test muscle strength and movement by moving the participant's arms, legs and neck. Photographs will be taken of the skin, hair and nails of they are abnormal. Blood tests will be done to check the liver and blood cell count. The participant and their legal guardian will answer questions about how the participant feels and about their health.
• Participants will then be scheduled for follow up visits at 3 months, 6 months, and 12 months. At each subsequent visit the following will be done: A complete examination of the skin, hair and nails; a test of muscle strength; photographs will be repeated; blood tests to check liver and blood cell counts; and questions about how the participant feels and about their health.

Inclusion Criteria:

• Received hematopoietic stem cell transplant
• Meet the diagnostic criteria for cutaneous cGVHD

Exclusion Criteria:

• Previous HSCT (other then the current HSCT)

The research subject population is children who have received hematopoietic stem cell transplant and developed chronic graft-versus-host disease. All children seen at the pediatric GVHD clinic at the Dana-Farber Cancer Institute will be recruited.