Impacts of Posttransplant Cyclophosphamide Dose on Graft-versus-leukemia Effects via HLA-B Leader in HLA-haploidentical Peripheral Blood Stem Cell Transplantation.

INTRODUCTION: The graft-versus-leukemia effect of HLA-B leader dimorphism, i.e. methionine (M) or threonine (T) at position -21 of the leader sequence, has been observed in HLA-haploidentical hematopoietic cell transplantation with posttransplant cyclophosphamide (PTCy-haplo). However, the biological mechanism has been unclear, and the contributions of HLA-B leader genotype to risk reduction of relapse might be dependent on posttransplant cyclophosphamide (PTCy) doses. METHODS: To investigate whether the effect of HLA-B leader dimorphism was modified by the PTCy dose, we retrospectively analyzed 99 patients who received PTCy-haplo. RESULTS: In the low-dose PTCy group, the patient M+ HLA-B leader genotype did not significantly affect the cumulative incidence of relapse (CIR) but negatively impacted the overall survival (OS) compared to the M- genotype. In contrast, in the high-dose PTCy group, patients with the M+ genotype had a decreased CIR, but no significant difference in the OS was observed between patients with the M+ and M- genotypes. Regardless of PTCy doses, the patient M+ genotype had detrimental effects on nonrelapse mortality. CONCLUSION: Our findings suggest that the effect of the patient HLA-B leader genotype is modified by the PTCy dose, providing immunological insight into the PTCy dosage and supporting further studies to investigate the underlying mechanisms.

[Diffuse large B-cell lymphoma with markedly improved chylothorax by lymphangiography].

Chylothorax is a rare clinical sign in patients with diffuse large B-cell lymphoma (DLBCL), which is often challenging to manage and has a poor prognosis. We report the case of a 59-year-old woman who presented with right pleural effusion at the time of DLBCL diagnosis. Lymphadenopathy rapidly improved in response to chemotherapy. However, the pleural effusion progressed and was identified as chylothorax by thoracentesis. Because attempts to manage the condition with fasting and central venous nutrition were unsuccessful, we performed ultrasound-guided intranodal lipiodol lymphangiography from the inguinal lymph node. Although leak sites were not detected, the pleural effusion markedly improved on the day after the examination and resolved after 2 months. Lymphangiography is a minimally invasive examination with few complications. It contributes not only to the identification of leak sites but also to the improvement and resolution of chylothorax. Therefore, lymphangiography should be considered for refractory chylothorax that is unresponsive to chemotherapy or nutritional management.

Clinical usefulness of very high serum soluble interleukin-2 receptor levels for the detection of tuberculous peritonitis in a patient with chronic myelogenous leukemia.

Tuberculous peritonitis is difficult to diagnose due to the disadvantages of ascitic culture and peritoneal biopsy. Although previous reports suggested that very high serum soluble interleukin-2 receptor (sIL-2R) levels may reflect the clinical activity of tuberculosis, little is known about the diagnostic utility of serum sIL-2R for tuberculous peritonitis. We describe a case of tuberculous peritonitis with chronic myelogenous leukemia. The abnormally high serum sIL-2R value and negative findings for other possible causes including lymphoma suggested tuberculous peritonitis and we administered anti-tuberculosis treatment before definitive diagnosis. Abnormally high serum sIL-2R levels may contribute to earlier diagnosis of tuberculous peritonitis, along with ruling out other potential differential diagnoses.