D-TECT: Pretreatment D-dimers and Disease Control in Advanced cSCC Treated With Cemiplimab

Inclusion Criteria:

* Histologically confirmed locally advanced or metastatic cutaneous squamous cell carcinoma
* Planned initiation of systemic treatment with cemiplimab as part of routine clinical care
* Pretreatment D-dimer measurement performed within 7 days before initiation of cemiplimab treatment up to the day of first administration before infusion
* Age 18 years or older at the time of consent
* ECOG performance status 0 to 2
* Written informed consent for study participation and pseudonymized collection and analysis of clinical and laboratory data

Exclusion Criteria:

* Prior treatment with immune checkpoint inhibitors in curative or palliative intent for cutaneous squamous cell carcinoma
* Concurrent second malignancy requiring systemic treatment, such as chemotherapy, immunotherapy, or targeted therapy
* Clinically unstable comorbidity, including NYHA class III-IV heart failure or active systemic infection
* Acute symptomatic thrombosis or pulmonary embolism within 4 weeks before the pretreatment D-dimer measurement
* Incidental asymptomatic thromboembolic events detected during clinical diagnostic work-up or following an elevated D-dimer result are not exclusion criteria and will be documented
* Physician-estimated life expectancy of less than 3 months or severe non-tumor-related comorbidity likely to preclude assessment of the clinical course within the first 6 months
* Lack of capacity to consent or legal guardianship without valid legal representation