Adult patients (≥18 years) with confirmed cutaneous T-cell lymphoma evaluated at Hospital México between 2019 and 2025 will be retrospectively analyzed using EDUS records to describe their epidemiological profile, clinical characteristics, treatments, and outcomes.

This retrospective observational study will analyze adult patients (≥18 years) with a confirmed diagnosis of cutaneous T-cell lymphoma evaluated in the Dermatology Service of Hospital México between January 2019 and December 2025. Data will be obtained from electronic medical records (EDUS), including sociodemographic characteristics, clinical presentation, histopathological and immunohistochemical findings, disease staging, treatment modalities, and clinical outcomes.

Patients must have at least one documented dermatological evaluation and have received treatment, including skin-directed therapies and/or systemic therapies. Records that are incomplete, inconsistent, or lack histopathological confirmation will be excluded.

The study aims to characterize local epidemiological and therapeutic patterns and describe clinical outcomes using descriptive statistical analysis, providing updated real-world evidence to support clinical decision-making and optimize management strategies for cutaneous T-cell lymphoma in a national referral center.

Inclusion Criteria:

• Patients with a confirmed diagnosis of cutaneous T-cell lymphoma, established through clinical, histopathological, and immunohistochemical criteria, documented in EDUS of Hospital México in the Dermatology Service of Hospital México during the period between January 2019 and December 2025.
• Patients aged 18 years or older, of both sexes.
• Patients with at least one dermatological evaluation recorded during the study period.
• Patients who, having a confirmed diagnosis, have received some modality of treatment, including skin-directed therapies (phototherapy, topical treatments, localized radiotherapy) and/or systemic treatments.

Exclusion Criteria:

• Clinical records that are insufficient or incomplete, preventing adequate diagnostic classification, staging, therapeutic characterization, or evaluation of clinical evolution.
• Patients with a presumptive diagnosis of cutaneous T-cell lymphoma without histopathological confirmation.
• Duplicate or inconsistent records that hinder the correct identification and classification of the patient.
• Patients attended outside the established study period.
• Patients outside the age range.
• Patients who do not belong to the Dermatology Service of Hospital México.

he study population will consist of adult patients (≥18 years) of both sexes with a confirmed diagnosis of cutaneous T-cell lymphoma, established through clinical, histopathological, and immunohistochemical criteria, and documented in EDUS at the Dermatology Service of Hospital México between January 2019 and December 2025. Patients must have at least one recorded dermatological evaluation during the study period and must have received some form of treatment, including skin-directed therapies (phototherapy, topical treatments, localized radiotherapy) and/or systemic therapies.

Patients with insufficient or incomplete clinical records that prevent adequate diagnostic classification, staging, therapeutic characterization, or evaluation of clinical evolution will be excluded, as well as those with a presumptive diagnosis without histopathological confirmation, duplicate or inconsistent records, patients attended outside the study period, those outside the defined age range, and patients.

According to protocol