This is a single center 2-phase study to assess effects of using text messages on adherence to oral chemotherapy for patients with acute lymphoblastic leukemia (ALL) or T-cell lymphoblastic lymphoma.

The study will begin with a 28-day pilot phase where participants will be asked to complete questionnaires to determine if the text message intervention is acceptable to participants.

In the efficacy phase, the study will compare adherence to oral mercaptopurine and methotrexate between those who receive the high intensity text message intervention and those who receive standard-of-care. It is believed that high-intensity text messages will increase patient adherence within cycle 1.

Inclusion Criteria:

• Age of 15 years or older at time of enrollment
• Diagnosed with ALL or T-cell lymphoblastic lymphoma
• Currently receiving treatment with pediatric-based regimen that includes maintenance with mercaptopurine and methotrexate (e.g., CALGB 10403). Study participation begins with the start of maintenance, so enrollment occurs prior to the start of maintenance. Patients in the pilot phase may have already started maintenance as long as the end of their maintenance therapy is scheduled to occur after the end of the 28-day pilot intervention.

Exclusion Criteria:

• Patient or caregiver who would receive text message reminders does not have a cell phone that receives text messages
• Patient does not wish to participate
• Text messages will be crafted in the patient's preferred language for medical communication, so English fluency is not an enrollment requirement.

Study results including PHI such as dates, assigned study ID, and initials may be shared with researchers and their teams at other sites as part of required safety reporting notifications (e.g. serious events/unanticipated problems, or other reportable events). Final reports (no PHI) may also be shared. Names and medical record numbers will not be shared externally.

Data will only be shared for analysis purposes.