This is an observational, multicenter, international and retrospective study, that aims to collect data on clinical and pathological characteristics, treatment regimens, outcome, and prognostic factors (clinical, biomarkers and/or radio-metabolic) in patients affected by PBL.

This study is an International, multicenter, observational, retrospective trial on patients affected by PBL. The information collected aim to obtain data from the real-life diagnosis, staging, management and treatment and outcome of PBL patients. A centralized pathological review of pathological samples is planned to define the rate of accurate diagnosis and to define a recommended immunohistochemical diagnostic panel for PBL. In addition, exploratory analysis will be performed to better characterize PBL.

Inclusion Criteria:

• Diagnosis of plasmablastic lymphoma (PBL) between Jan 1st 2000, and Dec 31st 2022
• Histologically confirmed plasmablastic lymphoma (PBL) diagnosis according to local pathological report
• Age > 18 years old
• Availability of complete medical records
• Availability of histopathological material requested by the study

Exclusion Criteria:

• Any other histology than PBL
• Lack of complete medical records
• Lack of histopathological material requested by the study

Patients (Age ≥ 18 years old) with diagnosis of plasmablastic lymphoma (Histologically confirmed) between Jan 1st 2000, and Dec 31st 2022

Qualified researchers may contact the FIL board at segreteriadirezione@filinf.it to share invidual-level patients' clinical data analysed for the publication article (for the avoidance of doubt, no identifiable data, such as name, address, hospital name, date of birth, or any other identifying data, will be shared and should not be requested).

In compliance with the domestic ethics guideline and applicable legislation, invidual deindentified patients' data underlying the results reported in teh publication article (including study protocol, statistical analysis plan and data coding) can be shared until 5 years after the publication of the present article.

For each data sharing request, it is essential that a proforma (available on request) is completed that describes the general purpose, specific aims, data items requested, analysis plan and acknowledgment of the trial management team. Requests will be reviewed based on scientific merit and ethical principles. Requestors who are granted access to the data will be required to complete a data sharing agreement that will be signed by the requester and FIL.