Feasibility of Semi-Permanent Tattoo for Treatment Alignment in Radiation Therapy

Inclusion Criteria: * Patients requiring medical tattoo for treatment alignment. * Patient being treated with some form of image guidance including kV, MV, or cone-beam CT. * Age ≥ 18. * Eastern Cooperative Oncology Group (ECOG) performance status 0-2. * Patients will engage in the informed consent process and provide study-specific informed consent prior to study entry and must be willing to have photos taken of their tattoos through the treatment and follow-up process and may be required to take pictures of their own tattoo to submit to the research team. * Patient able to send picture of tattoo via secure messaging. Exclusion Criteria: * Known allergies or hypersensitivity to tattoo ink. * Personal or religious objection to medical tattooing. * Autoimmune or skin disorders which may be worsened by medical tattooing. * Inability to complete the required forms; however, verbal completion is adequate if recorded on the consent documents.