Tolerability of Daratumumab Amongst Asian Patients with Plasma Cell Dyscrasias - A Single Centre Experience.

Daratumumab is increasingly incorporated into the standard treatment regimens for patients with plasma cell dyscrasias in Asia, especially with cost-containment measures implemented by various regional health authorities. This analysis aimed to study daratumumab's tolerability amongst Asian patients. This is a retrospective medical records review of patients who received daratumumab between November 2016 and August 2021 as part of routine clinical care. Sixty-two patients were included in the study: 62.9% had renal impairment, and 27.4% had creatinine clearance (CrCl) \<30ml/min. Forty-five patients (72.6%) received daratumumab combination therapy, with a median 1 line of prior therapy. The median duration of follow-up was 12.4 months, and the median duration patients were on treatment with daratumumab was 12.3 months. Twenty-one of 62 (33.9%) patients experienced infusion-related reactions (IRRs) after the first dose of intravenous daratumumab. Seven developed mostly grades 1 and 2 respiratory events, and 14 showed grades 1 and 2 non-respiratory IRRs. Only one patient experienced a grade 1 IRR with the second infusion, with none developing any IRRs in the third or subsequent infusions. Eight (12.9%) patients were affected by hematological adverse events (AEs), mostly grades 2 and 3, with one experiencing grade-4 neutropenia without sepsis. Six (9.7%) patients experienced non-hematological AEs, the commonest being pneumonia and other infections, with one developing Nocardia pneumonia (grade 4) 14 months after the initiation of daratumumab. In conclusion, daratumumab is tolerable amongst Asian patients, including the elderly, and patients with severe renal impairment and chronic lung diseases.

A Retrospective Review of Secondary Hemophagocytic Lymphohistiocytosis (HLH) and Dengue-associated HLH from a Teaching Hospital in Singapore.

Real-world data on the outcome of Asian patients with secondary hemophagocytic lymphohistiocytosis (HLH), especially on dengue-associated HLH, are limited to small case series. This is a retrospective records review of adult patients with secondary HLH between 2015 and 2020. Thirty-two adult patients were followed up for a median of 6.6 months (range 0.1 - 75 months). 15 had underlying lymphomas, and 12 had viral infections. Hemophagocytosis was seen in 28 of 29 patients with a bone marrow biopsy. 100% and 76.5% of patients with and without an underlying malignancy required HLH-directed therapy and blood product transfusion. 12 of 15 patients with lymphomas were treated with additional chemotherapy. Patients with malignancy-associated HLH had poorer survival than non-malignancy-associated HLH (median overall survival (OS) 1.5 months versus not reached, p-value 0.003). The 1-year survival rates of patients with malignancy-associated HLH, HLH with unknown etiologies, and infection-associated HLH were 0.133 (95% CI: 0.036 - 0.484), 0.400 (95% CI: 0.137 - 1.000) and 0.833 (95% CI: 0.647 - 1.000), respectively. Malignancy significantly increased the risk of death compared to infection-associated HLH (HR 9.37, p-value 0.003). Eight patients were diagnosed with dengue-associated HLH with a median HSCORE of 240 (98-99% probability of HLH). Their mean ferritin was 34,740 ng/mL. Three patients required blood product transfusion, 5 required corticosteroids and/or etoposide, with a median duration of treatment of 31 days. Their overall survival rate was 87.5%. Our study highlights the stark contrast in the survival of secondary HLH patients with and without an underlying malignancy. We also present one of the world's most extensive case series of dengue-associated HLH.

Case 33. Diagnostic difficulty in a patient with acute leukemia.

A provisional diagnosis of acute myeloid leukemia, FAB type M2, was made in a 24-year-old woman. Immunophenotyping led to reassessment of the diagnosis.

Case 41. A misdiagnosis of erythroleukemia.

A 57-year-old woman with splenomegaly, moderate anemia and a paraspinal mass was found to have strikingly increased erythropoiesis, which was left shifted and dysplastic with many multinucleated cells. An increased percentage of CD34-positive and CD117-positive cells suggested a diagnosis of pure erythroleukemia. Further investigations were performed.