Inclusion Criteria:  (1) Adults age 18 years or older at time of NET diagnosis (2) Diagnosis of GEP-NET or lung NET between 1/1/2019 and 12/31/2023, as evidenced by (a) medical record information on diagnoses and/or medications and/or treatments and/or test results and/or clinical notes and/or procedures and/or encounters and/or tumor characteristics, and ( b) patient self-report of their diagnosis.  Exclusion Criteria:  (1) Any GEP-NET/Lung NET prior to 1/1/19, as evidenced by (a) Medical record information on diagnoses and/or medications and/or treatments and/or test results and/or clinical notes and/or procedures and/or encounters and/or tumor characteristics, and (b) patient self-report of their diagnosis. (2) No evidence of NET treatment at the study site as evidenced by medical record information on provider encounters and / or patient is deceased per vital status.