Retrospective study based on data already available at each Center. Pseudonymized CT images of each patient in DICOM format will be sent from each center to the Coordinating Center to perform radiomics analysis.

Retrospective study based on data already available at each Center. Participating Centers will identify patients based on shared inclusion/exclusion criteria. Pseudonymized CT images of each patient in DICOM format will be sent from each center to the Coordinating Center to perform radiomics analysis. Images will be transferred via File Transfer Protocol while respecting the anonymity of enrolled patients. Images will be deposited in a dedicated study folder created by the AOUBO ICT Service. Images will be accessible only to the Investigator and Principal Investigator and/or their delegates via personalized credentials, which can be accessed only from IRCCS AOUBO computers and facilities. The folder to which the images will be transferred will be accessible only to the Principal Investigator and his/her Collaborators through customized private credentials usable only through IRCCS AOUBO networks, computers and facilities. Radiomics, which will be applied to existing CT images, will in no way affect the care pathway of patients

Inclusion Criteria:

• Age ≥18 years
• Patients with adrenal tumor who underwent adrenectomy surgery from 1-1-2000 to 30-5-2023, performed according to clinical necessity and indications of international guidelines,with availability of histologic diagnosis or adrenal tumor that did not undergo adrenectomy surgery with diagnosis of benignity confirmed by radiologic stability at 6-12 months after first finding(as indicated in guidelines)
• Availability of radiological images in DICOM format of abdominal CT scan in which the adrenal tumor is first described, obtained on the date of first evaluation at the participating center (necessarily before surgery for patients undergoing adrenectomy)
• Signature of informed consent

Exclusion Criteria:

• none

Patients in the study will be enrolled at participating centers, selected from those who meet the inclusion/exclusion criteria.