Polatuzumab vedotin, rituximab, and bendamustine combination in relapsed or refractory diffuse large B-cell lymphoma: A real-world data from Turkey

Polatuzumab vedotin (Pola) with bendamustine and rituximab (BR) is a promising option for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). We analyzed the data of 71 R/R DLBCL patients who had been treated with Pola-BR in the named patient program from March 2018 to April 2021 from 32 centers in Turkey. All patients received up to six cycles of Pola 1.8 mg/kg, rituximab 375 mg/m2 on day 1, and bendamustine 90 mg/m2 on days 1–2 of each cycle. Median age at Pola-BR initiation was 55 (19–84). The overall response rate was 47.9%, including 32.4% CR rate when a median of 3 cycles was applied. With a median follow-up of 5 months, the median OS was 5 months. Grade 3–4 neutropenia and thrombocytopenia were the most common hematological toxicities. The real-world data from our cohort showed the Pola-BR is an effective option with a manageable toxicity profile

Atypical Hemolytic Uremic Syndrome: Differential Diagnosis from TTP/HUS and Management

Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy (TMA). It has an unfavorable outcome with death rates as high as 25% during the acute phase and up to 50% of cases progressing to end-stage renal failure. Uncontrolled complement activation through the alternative pathway is thought to be the main underlying pathopysiology of aHUS and corresponds to all the deleterious findings of the disease. Thrombotic thrombocytopenic purpura (TTP) and Shiga toxin-associated HUS are the 2 other important TMA diseases. Although differentiating HUS from TTP is relatively easy in children with a preceding diarrheal illness or invasive S. pneumoniae, differentiating aHUS from TTP or other microangiopathic disorders can present a major diagnostic challenge in adults. ADAMTS13 analysis is currently the most informative diagnostic test for differentiating TTP, congenital TTP, and aHUS. Today empiric plasma therapy still is recommended by expert opinion to be used as early as possible in any patient with symptoms of aHUS. The overall treatment goal remains restoration of a physiological balance between activation and control of the alternative complement pathway. So it is a reasonable approach to block the terminal complement complex with eculizumab in order to prevent further organ injury and increase the likelihood organ recovery. Persistence of hemolysis or lack of improvement of renal function after 3-5 daily plasmaphereses have to be regarded as the major criteria for uncontrolled TMA even if platelet count has normalized and as an indication to switch the treatment to eculizumab. Eculizumab has changed the future perspectives of patients with aHUS and both the FDA and the EMA have approved it as life-long treatment. However, there are still some unresolved issues about the follow-up such as the optimal duration of eculizumab treatment and whether it can be stopped or how to stop the therapy

Analysis of p53 Tumor Suppressor Pathway Genes in Chronic Lymphocytic Leukemia

The p53 tumor suppressor gene plays an important role in preventing tumor development. The p53 protein interacts with other p53 signal pathway members to control cell proliferation. In this study, expression of the p53, Human homolog of murine Double Minute 2 (HDM2), p14Alternating Reading Frame (ARF), Zinc Finger and BTB domain containing 7A (ZBTB7A), and B-Cell Lymphoma 6 (BCL6) genes was quantitatively investigated by real-time polymerase chain reaction (PCR) in the peripheral blood of patients with chronic lymphocytic leukemia (CLL) and healthy controls. Plasma fibronectin levels were determined by enzyme-linked immunosorbent assay. Expression of the p53, p14, and HDM2 genes were significantly higher in the patients. However, ZBTB7A and BCL6 gene expression was not detectable in both groups. A positive correlation between p14ARF and HDM2 expression and a negative correlation between p53 and p14ARF expression was observed. Expression of the p14ARF and HDM2 genes were inversely correlated in the control group. Neither HDM2 nor p14ARF gene expression was correlated with p53 expression. The p53 gene was also analyzed for the presence of mutations. A splice-site mutation was found in a single patient. Our findings indicate that expression of the p53, p14ARF, and HDM2 genes are associated with CLL. Elucidation of the mutual interactions at the protein level warrants further studies