Summary: Objective: To report synovial fluid lactate concentrations in normal and pathological canine joints.Study design: Controlled, prospective study.Methods: Lactate was measured in synovial fluid using a hand-held meter and the rest of the fluid was sent to a commercial laboratory for analysis. Samples were divided into four groups; group 1: control, group 2: osteoarthritis, group 3: immune-mediated inflammatory arthritis, and group 4: septic arthritis. Statistical analysis was performed to compare lactate concentrations between the four groups and to examine the predictive value of lactate in the diagnosis of septic arthritis. A correlation was sought between synovial fluid lactate and synovial fluid total nucleated cell count and total protein.Results: Seventy-four samples were investigated from 55 dogs. Statistical analysis found that lactate concentrations were significantly higher in the septic arthritis group than in each of the other three groups. No significant correlation could be found between synovial fluid lactate concentrations and synovial fluid total nucleated cell count or synovial fluid total protein. Lactate concentration was found to be a useful predictor of septic arthritis, with a low concentration pointing towards exclusion rather than a high concentration to the diagnosis of septic arthritis.Clinical significance: Synovial fluid lactate concentration is not a good marker for osteoarthritis or immune-mediated inflammatory arthritis, but it is significantly increased in septic arthritis and could help the clinician in ruling out this condition in a quick and cost-effective way.

Purpose: This phase II clinical trial evaluated the combination of ibrutinib with rituximab, gemcitabine, and oxaliplatin (R-GemOx) in patients with nongerminal center B-cell–like (non-GCB) diffuse large B-cell lymphoma (DLBCL). Patients and Methods: The IBDCL trial (NCT02692248) included patients with histologic diagnosis of non-GCB DLBCL with relapsed or refractory disease and non-candidates for stem-cell transplantation. Patients received an induction treatment consisting of six or eight cycles of R-GemOx at standard doses every 2 weeks, in combination with ibrutinib (560 mg daily), followed by a maintenance treatment with ibrutinib for a maximum of 2 years. The primary objective was to evaluate the overall response rate after four cycles. Results: Sixty-four patients were included, 72% of them refractory to the last regimen. The overall response rate and complete remission rate after the fourth cycle were 53% [95% confidence interval (CI), 41–65] and 34% (95% CI, 24–46), respectively. Twenty-four (37%) patients started maintenance, and 7 (11%) completed the planned 2 years. After a median follow-up of 29.7 months (range: 0.4–48.6), the estimated 2-year progression-free survival and overall survival were 18% (95% CI, 8–28) and 26% (95% CI, 14–37), respectively. The most common grade ≥3 treatment-related adverse events were thrombocytopenia (44%), neutropenia (30%), and anemia (14%). Grade ≥3 infectious and cardiovascular treatment-related adverse events were reported in 6 (9%) and 1 (2%) patient, respectively. Conclusions: Ibrutinib in combination with R-GemOx, followed by ibrutinib maintenance, demonstrated encouraging antitumor activity with durable responses and a manageable toxicity in patients with non-GCB DLBCL.

The British Journal of Haematology publishes original research papers in clinical, laboratory and experimental haematology. The Journal also features annotations, reviews, short reports, images in haematology and Letters to the Editor.

Background: Assessment of bone marrow infiltration (BMI) is part of the initial staging of mantle cell lymphoma (MCL), although BMI evaluated by biopsy (BMB) is not considered significant in the MIPI scales, and standardized recommendations remain lacking. Objectives: To evaluate the accuracy and prognostic impact of BMI assessed by PET/CT and BMB in a large series of MCL patients. Methods: We deconstructed the IPI-NCCN, MIPI, and MIPI-c indices and considered BMI as positive if indicated by a BMB, PET/CT scan, or a combination of both. Results: In the total cohort (n = 148), 110 patients had BMI detected by BMB and 33 by PET/CT. The sensitivity of BMB was higher than that of PET/CT (94.8% vs. 28.4%), as were its negative predictive value (84.2% vs. 27.8%) and accuracy (95.9% vs. 43.9%). In the total cohort, BMI detected by PET/CT showed a significant predictive value for PFS (p = 0.027), while BMB demonstrated independent prognostic value only in combination with PET/CT (p = 0.025). Among intensively treated patients (n = 128), PET/CT had significant clinical impact on PFS (p = 0.030), and when combined with BMB, it provided independent prognostic value for both PFS and OS (p = 0.026 and p = 0.033, respectively). Based on these findings, we propose a prognostic model (MCL-PET-I) that incorporates BMI by PET/CT, allowing for the identification of three groups with distinct clinical outcomes (p < 0.0001 for PFS and p = 0.00025 for OS). Conclusions: In the upfront work of MCL, PET/CT-based BMI has greater prognostic impact, while BMB remains essential for staging. We propose the MCL-PET-I prognostic index, which effectively differentiates between clinical risk groups.