Lymphoid chronic B-cell malignancies are frequent pathologies that affect adults, with a very variable prognosis and treatment (some of them can remain untreated). The diagnosis of these malignancies relies on the study of the morphology of tumoral cells and the expression by these cells of several markers, mainly via a technical approach called flow cytometry. Because the markers currently used remain imperfect, additional ones are needed for an accurate diagnosis that affect both prognosis and treatment.

In addition, because numerous markers are used at the diagnosis, there is a need of tools that synthetize the multi-dimensional structure of the data obtained.

The primary purpose of this study is to detect new markers that can be of help for the diagnosis of Marginal Zone Lymphoma and other B-cell chronic lymphoid malignancies.

The secondary purpose of this study is to obtain a statistical algorithm that allow a good prediction of the different sub-types of chronic B-cell malignancies mainly using the results of flow cytometry.

Inclusion Criteria:

• patients over 18 years-old with of Marginal Zone Lymphoma and other B-cell chronic lymphoid malignancies
• patients that gave their informed consent for the conservation of blood or bone marrow cells (primary objective 1)
• patients that gave their informed consent for the retrospective use of their clinical and biological data

Exclusion Criteria:

• patients under guardianship or curatorship
• patients who did not gave their consent for the use of their cells and/or data

Patients over 18 years-old with of Marginal Zone Lymphoma and other B-cell chronic lymphoid malignancies