Day-21 bone marrow findings incorrectly designate residual leukaemia in FLT3-mutated acute myeloid leukaemia treated with intensive induction plus midostaurin: a morphology-focused study.

Early induction response assessment with day-21 bone marrow (D21-BM) is commonly performed in patients with FLT3-mutated acute myeloid leukaemia (AML), where detection of residual leukaemia (RL; blasts ≥5%) typically results in the administration of a second induction course. However, whether D21-BM results predict for RL at the end of first induction has not been systematically assessed. This study evaluates the predictive role of D21-BM morphology in detecting RL following first induction. Between August 2018 and March 2022, all patients with FLT3-AML receiving 7+3 plus midostaurin, with D21-BM performed, were identified. Correlation between D21-BM morphology vs D21-BM ancillary flow/molecular results, as well as vs D28-BM end of first induction response, were retrospectively reviewed. Subsequently, D21-BMs were subjected to anonymised morphological re-assessments by independent haematopathologists (total in triplicate per patient). Of nine patients included in this study, three (33%) were designated to have RL at D21-BM, all of whom entered complete remission at D28-BM. Furthermore, only low-level measurable residual disease was detected in all three cases by flow or molecular methods at D21-BM, hence none proceeded to a second induction. Independent re-evaluations of these cases failed to correctly reassign D21-BM responses, yielding a final false positive rate of 33%. In summary, based on morphology alone, D21-BM assessment following 7+3 intensive induction plus midostaurin for FLT3-AML incorrectly designates RL in some patients; thus correlating with associated flow and molecular results is essential before concluding RL following first induction. Where remission status is unclear, repeat D28-BMs should be performed.

Customized Integrating-Sphere System for Absolute Color Measurement of Silk Cocoon with Corrugated Microstructure.

Silk fiber, recognized as a versatile bioresource, holds wide-ranging significance in agriculture and the textile industry. During the breeding of silkworms to yield new varieties, optical sensing techniques have been employed to distinguish the colors of silk cocoons, aiming to assess their improved suitability across diverse industries. Despite visual comparison retaining its primary role in differentiating colors among a range of silk fibers, the presence of uneven surface texture leads to color distortion and inconsistent color perception at varying viewing angles. As a result, these distorted and inconsistent visual assessments contribute to unnecessary fiber wastage within the textile industry. To solve these issues, we have devised an optical system employing an integrating sphere to deliver consistent and uniform illumination from all orientations. Utilizing a ColorChecker, we calibrated the RGB values of silk cocoon images taken within the integrating sphere setup. This process accurately extracts the authentic RGB values of the silk cocoons. Our study not only helps in unraveling the intricate color of silk cocoons but also presents a unique approach applicable to various specimens with uneven surface textures.

Pulse Oximetry Imaging System Using Spatially Uniform Dual Wavelength Illumination.

Pulse oximetry is a non-invasive method for measuring blood oxygen saturation. However, its detection scheme heavily relies on single-point measurements. If the oxygen saturation is measured at a single location, the measurements are influenced by the profile of illumination, spatial variations in blood flow, and skin pigment. To overcome these issues, imaging systems that measure the distribution of oxygen saturation have been demonstrated. However, previous imaging systems have relied on red and near-infrared illuminations with different profiles, resulting in inconsistent ratios between transmitted red and near-infrared light over space. Such inconsistent ratios can introduce fundamental errors when calculating the spatial distribution of oxygen saturation. In this study, we developed a novel illumination system specifically designed for a pulse oximetry imaging system. For the illumination system, we customized the integrating sphere by coating a mixture of barium sulfate and white paint inside it and by coupling eight red and eight near-infrared LEDs. The illumination system created identical patterns of red and near-infrared illuminations that were spatially uniform. This allowed the ratio between transmitted red and near-infrared light to be consistent over space, enabling the calculation of the spatial distribution of oxygen saturation. We believe our developed pulse oximetry imaging system can be used to obtain spatial information on blood oxygen saturation that provides insight into the oxygenation of the blood contained within the peripheral region of the tissue.

Low rates of venous thromboembolism in hospitalised COVID-19 patients: an Australian experience.

BACKGROUND: Venous thromboembolic (VTE) complications appear common in hospitalised COVID-19 patients, particularly among critically ill patients in intensive care units. However, there is significant heterogeneity in the reported use of thromboprophylaxis. AIMS: The primary objective was to determine rates of symptomatic VTE in hospitalised COVID-19 patients. Secondary objectives were to assess adherence to an institutional risk-adapted thromboprophylaxis guideline, and rates of bleeding complications. METHODS: A retrospective, single-centre, cohort study was performed in consecutive hospitalised COVID-19 patients over a 6-month period (March to August 2020). Enoxaparin was used as thromboprophylaxis in all patients without a contraindication, with dose adjusted according to disease severity, weight and renal function. RESULTS: Among 86 hospitalised COVID-19 patients, no VTE were identified. Eighty-one (94%) patients received anticoagulation, with 90% adherence to institutional thromboprophylaxis guidelines. Four bleeding events occurred, with one clinically relevant non-major bleeding event and three minor bleeding events. CONCLUSION: Low rates of VTE were identified in hospitalised COVID-19 patients using a risk-adapted thromboprophylaxis protocol.

Cytarabine-based induction immunochemotherapy in the front-line treatment of older patients with mantle cell lymphoma.

The role of cytarabine-based induction and autologous stem cell transplantation (ASCT) in front-line treatment of younger patients with mantle cell lymphoma (MCL) is well established, however the utility of intensive approaches in older patients remains unclear. This retrospective study compared first line treatment outcomes in patients aged 60 years or more, treated at six tertiary centres between 2000-2015. 70 patients included had a median age of 69 (60-91) and most (94%) demonstrated advanced stage disease. Treatment regimens included: R-CHOP-like (n = 39), alternating R-CHOP/R-DHAC (n = 10), R-HyperCVAD/R-MA (n = 7), R-CHOP/Cytarabine (Nordic Protocol) (n = 10) and other (n = 4). 16 patients underwent an ASCT. The median follow-up for surviving patients was 37 months. Compared to R-CHOP-like therapies, cytarabine-based regimens were associated with an improved overall response rate (ORR) of 70% vs 33% (p < 0.001) and overall survival (OS) (HR 0.541, [0.292-1.001], p = 0.05). No difference in efficacy between different cytarabine-based regimens was detected, but R-HyperCVAD/R-MA was associated with increased hospitalisation and transfusion requirements. Patients undergoing ASCT demonstrated an improved median OS (HR 0.108 [0.015-0.796], p = 0.029) but were significantly younger. These results reaffirm the use of cytarabine in MCL for selected patients aged over 60. Such regimens should be strongly considered for this population in frontline therapy.

Role of bone marrow biopsy for fever of unknown origin in the contemporary Australian context.

BACKGROUND: Bone marrow biopsy (BMB) is an accepted investigation in fever of unknown origin (FUO) to uncover haematological malignancies, such as lymphoma, and sometimes infections. With the advance in imaging modalities, such as 18-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) to identify the focus of lymphoma, BMB may not contribute to the diagnosis when there are no other clinical features to suggest an underlying haematological disease. AIM: To investigate the utility of BMB in determining the cause of FUO, when there are no other indications for BMB. METHODS: Medical records of adult patients who had BMB performed for FUO or febrile illness from 1 January 2005 to 31 December 2014 in four metropolitan tertiary hospitals in Melbourne, Australia were reviewed. Patients with other concurrent indications for BMB, known human immunodeficiency virus infection and previously diagnosed connective tissue diseases were excluded. RESULTS: Seventy-three patients were included in the study. Fifty-one patients had a final diagnosis for fever (systemic inflammatory diseases, infective, malignancy or other) while 22 patients had no diagnoses. In only 10 patients (13.7%) did BMB contribute to the diagnosis, finding either malignancy or granulomata. However, all these diagnoses could have been made without BMB. Two patients with diffuse large B-cell lymphoma had normal BMB. FDG-PET was helpful in making a diagnosis in eight (25%) out of 32 patients. CONCLUSION: Performing BMB in patients with FUO and no other haematological abnormalities is of very limited value, and other investigations, such as FDG-PET, may be more likely to help establish a definitive diagnosis.

Incidence and outcomes of catheter related thrombosis (CRT) in patients with acute leukemia using a platelet-adjusted low molecular weight heparin regimen.

Patients with acute leukemia frequently develop catheter-related thrombosis (CRT) despite concurrent thrombocytopenia. The incidence, treatment and outcomes of this complication are poorly documented. We undertook this study to determine the incidence of CRT in patients with acute leukemia and assess the safety and effectiveness of a treatment strategy using a platelet-adjusted low molecular weight heparin (LMWH) dosing protocol. Patients (18 years and older) with newly diagnosed acute leukemia from January 2014 to December 2015 who received central venous catheters were included. The clinical data were reviewed up to 12 months from acute leukemia diagnosis to capture objectively documented CRT events. The outcome events including recurrent venous thromboembolism (VTE), bleeding events, infectious or mechanical complications, and death were reported up to 3 months from the time of CRT diagnosis. The incidence of CRT among 214 patients was 10.7% (23 patients) in the first 12 months after acute leukemia diagnosis. Among 18 patients who were treated with anticoagulation, 14 (78%) received reduced LMWH dosing due to concurrent thrombocytopenia. There were no recurrent VTE episodes, but 3 patients experienced bleeding events while on anticoagulation. Fifteen patients (83%) completed a minimum of 3 months anticoagulation. Twelve patients (52%) experienced an infectious complication, which was the main reason for catheter removal. Deaths occurred in 2 patients, related to underlying acute leukemia during 3 months period following CRT. Symptomatic CRT is frequent in patients with acute leukemia. Platelet-adjusted LMWH dosing may be effective and well tolerated despite thrombocytopenia.