The study is based on the constitution of a collection of tumor and blood samples for the development of tumoroid for functional tests to predict clinical response to treatment.

Inclusion Criteria:

• Patient with undifferentiated primary carcinoma (UPC) with histological and immunohistochemical evidence, validated in a local and/or national UPC multidisciplinary consultation
• Patient with indication for systemic 1st-line treatment at the time of inclusion. Treatment may already have begun at the time of inclusion, but within the limit of 2 treatment cycles administered.
• Patient with life expectancy greater than 3 months
• Patient of legal age
• Patient affiliated to a social security scheme
• Signature of informed consent prior to any specific study procedure

Exclusion Criteria:

• Persons deprived of their liberty or under guardianship (including curatorship)
• Pregnant or breast-feeding patient

Patient with undifferentiated primary carcinoma (UPC) with indication for 1st-line treatment