Investigators plan to perform a pilot study that aims to characterize the microbiome of human cutaneous T cell lymphoma patients and compare this to the microbiome of age and sex matched controls.

Inclusion Criteria:

• Group 1: Patients with stage IA-IIA cutaneous T cell lymphoma
• Group 2: Patients with stage IIB and above cutaneous T cell lymphoma
• Group 3: Patients with CD30+ lymphoproliferative disorder including lymphomatoid papulosis and cutaneous anaplastic large cell lymphoma
• Group 4: Patients with plaque psoriasis with BSA>5% on routine phototherapy per standard of care
• Group 5: Patients with moderate to severe atopic dermatitis on routine bleach bath therapy per standard of care
• Group 6: Healthy individuals without the above skin conditions, similar age and sex distribution to the patients with cutaneous T cell lymphoma
• All Groups: subjects who are age 18-89 years of age at time of enrollment
• All Groups: Subjects who are able and willing to give informed consent for this study and the Dermatology Tissue Acquisition and Biorepository (STU00009443).

Exclusion Criteria:

• All Groups: Subjects who are younger than 18 years of age or older than 90 years of age
• All Groups: Subjects who are unable to give consent
• Patients currently on systemic antibiotics or recent (within past 4 weeks) exposure to systemic antibiotics
• We will not recruit the following populations: adults unable to consent, individuals who are not yet adults (infants, children, teenagers), pregnant women, prisoners and other vulnerable populations.

Patients with cutaneous T cell lymphoma, atopic dermatitis, and psoriasis and healthy individuals without any of these conditions will be enrolled at Northwestern Memorial Hospital Dermatology outpatient clinic.