Immunosuppression therapy is effective for both acquired tumor-associated and primary pure red cell aplasia: a match pair case-control study.

No agreement had been reached on the treatment of patients with pure red cell aplasia (PRCA) secondary to indolent malignancies. Data was collected from patients with acquired PRCA from May, 2014 to May, 2018 in Peking Union Medical College Hospital. Tumor-associated PRCA and primary PRCA patients were matched at a ratio of 1:2 with compatible baseline characteristics. All patients had been treated with CsA or sirolimus for at least 6 months with the efficacy and adverse events recorded. Twelve tumor-associated PRCA patients (3 thymoma, 8 lymphoproliferative disorders, and 1 smoldering multiple myeloma) with stable underling disease and 24 acquired primary PRCA patients were selected. 83.3% tumor-associated PRCA patients and 100% primary PRCA patients (P = 0.436) responded to immunosuppression therapy (IST) at a median of 2.5 and 3.5 months (P = 0.137), respectively. No different was found in side effects. The ORR at the end of a median of 21.5-month follow-up was 75% and 70.8% (P = 0.795), respectively. No tumor progression was reported except one secondary patient had lymphoma relapse after 2 years of IST and was given chemotherapy again. These results suggested IST had similar effect, safety on patients with tumor-associated, and primary PRCA patients when the tumors were stable.