Lenalidomide and Dexamethasone for Rosai-Dorfman Disease

• Histologically confirmed diagnosis of RDD
• Age ≥18 years
• Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
• Patients must have adequate renal, liver, and bone marrow function as defined by the following criteria:

Absolute neutrophil count ≥1500 cells per mm3 Platelet count ≥100000 cells per mm3 Creatinine clearance [according to Cockcroft formula] ≥60 mL/min. Aspartate aminotransferase and alanine aminotransferase ≤2·5×upper limit of normal [ULN], and total bilirubin ≤2·5×ULN; or ≤10×ULN in the case of known liver involvement by RDD.

• No active or untreated infection.
• No cardiac abnormalities.
• Subject provide written informed consent.
• A female is eligible to enter and participate in this study if she is of:

Non-childbearing potential including ω Any female who has had a surgical procedure rendering her incapable of becoming pregnant.

ω Subjects have experienced total cessation of menses for more than 1 year and be greater than 45 years in age.

⎫ Childbearing potential, including any female who has had a negative serum pregnancy test within 2 weeks prior to the first dose of study treatment, and agrees to use adequate contraception.

• Male subjects must use an effective barrier method of contraception during the study and for 90 days following the last course of MA if sexually active with a childbearing potential

Exclusion Criteria:

• Patients had concurrent malignancies.
• History of myocardial infarction, or unstable angina, or New York Heart Association (NYHA) Grade III-IV within 6 months prior to Day 1.
• Women who were pregnant or of childbearing potential.
• Known HIV seropositive, active hepatitis C infection, and/or hepatitis B (defined as HCV RNA≥1000 copies or HBV DNA ≥1000 copies at screening).
• Major surgical procedure within 28 days prior to the first dose of study treatment.
• Presence of uncontrolled infection.
• Evidence of active bleeding or bleeding diathesis.
• Any serious and/or unstable pre-existing medical, psychiatric, or other condition that could interfere with subject's safety, provision of informed consent, or compliance to study procedures.