Current perspectives on resistance to chimeric antigen receptor T-cell therapy and strategies to improve efficacy in B-cell lymphoma.

Although chimeric antigen receptor (CAR) T-cell therapy has demonstrated remarkable efficacy in patients with chemo-refractory B-cell lymphoma, a significant portion is refractory or relapse. Resistance is a major barrier to improving treatment efficacy and long-term survival in CAR T-cell therapy, and clinicians have very limited tools to discriminate a priori patients who will or will not respond to treatment. While CD19-negative relapses due to loss of target antigen is well described, it accounts for only about 30% of cases with treatment failure. Recent efforts have shed light on mechanisms of CD19-positive relapse due to tumor intrinsic resistance, T-cell quality/manufacturing, or CAR T-cell exhaustion mediated by hostile tumor microenvironment. Here, we review the latest updates of preclinical and clinical trials to investigate the mechanisms of resistance and relapse post CAR T-cell therapy in B cell lymphoma and discuss novel treatment strategies to overcome resistance as well as advances that are useful for a CAR T therapist to optimize and personalize CAR T-cell therapy.

The use of medium cutoff dialyzers in patients with multiple myeloma and acute kidney injury requiring hemodialysis: A systematic review.

BACKGROUND: Patients with multiple myeloma and high serum levels of circulating free light chains (FLC) have increased risk of acute kidney injury (AKI) secondary to cast nephropathy and is associated with poor survival. Despite removal of FLC by medium cutoff (MCO) dialyzer, the role of MCO hemodialysis (HD) in the treatment of cast nephropathy and its clinical benefits remain unknown. METHODS: A systematic review was conducted to establish the effectiveness of MCO dialyzer and clinical outcomes, compared to other forms of dialyzers in the removal of FLC, in myeloma patients with AKI. The primary outcome was effectiveness of MCO-HD in reducing serum FLC. The secondary outcomes were HD independence, estimated glomerular filtrate rate, mortality rates, length of hospitalization, rebound of serum FLC before the next dialysis, removal of other molecules during dialysis, and adverse events. RESULTS: We identified three case series, with a total of 17 patients. There were no randomized controlled trials (RCTs) or cohort studies. These case series showed that MCO dialyzer was effective in the removal of FLC and led to a reduction in FLC concentration post-dialysis. The majority of the case series did not have comparator arm and renal and/or other clinical outcomes. CONCLUSION: MCO dialyzer appeared to be effective in the removal of FLC based on the existing limited data. However, more data, particularly large-scale RCTs, are needed to assess the use of MCO dialyzer in reducing serum FLC and its effect on clinical outcomes in patients with multiple myeloma and AKI.

Risk factors for pregnancy-associated venous thromboembolism in Singapore.

OBJECTIVES: Pregnancy-associated venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), is associated with increased risk of maternal mortality and morbidity. This study aimed to assess potential risk factors for pregnancy-associated VTE. METHODS: In this case-control study, women with pregnancy-associated VTE were identified via International Classification of Diseases codes and included if they had been objectively diagnosed with VTE during pregnancy or within six weeks postpartum, from 2004 to 2016, at KK Women's and Children's Hospital or Singapore General Hospital in Singapore. Controls, i.e. pregnant women without VTE, were selected from a prospective longitudinal study. The odds ratio (OR) for VTE was computed for a range of maternal and obstetric factors. RESULTS AND CONCLUSIONS: From 2004 to 2016, 89 cases of pregnancy-associated VTE and 926 controls were identifed and analysed using logistic regression. The most significant risk factors for pregnancy-associated VTE were smoking (OR 5.44, p=0.0002) and preterm delivery (OR 5.06, p=0.023). Malay race, multiparity, non-O blood group and caesarean section, were also identified to be of higher risk. These risk factors should be useful in the development of thromboprophylaxis strategies for pregnancy and the postpartum period, especially in Singapore.

Factors Affecting Patient and Caregiver Preferences for Treatment of Myeloma and Indolent Lymphoma.

PURPOSE: Treatment options for myeloma and indolent lymphoma are increasing exponentially, with distinct efficacy, side effects, and cost. We aim to determine the factors influencing patient and caregiver treatment preferences. METHODS: Patients and caregivers of patients with myeloma and indolent lymphoma were recruited from two cancer centers in Singapore. Preferences were elicited using a discrete choice experiment. Attributes and levels were selected based on a previous qualitative study. The relative preference for levels within each attribute (part worth utility values) and the extent to which an attribute would influence decision making (relative importance) were calculated. Patient and caregiver participation in the treatment plan selection process were assessed using the Control Preference Scale. RESULTS: One hundred ninety-nine patients and 169 caregivers were recruited. Patients placed the highest importance on out-of-pocket costs (relative importance = 35%), followed by efficacy (25%), persistent side effects (19%), administration route (8%), treatment duration (7%), and short-term side effects (5%). Caregivers ranked efficacy (27%) as the most important attribute, over out-of-pocket costs (24%). Most patients preferred a collaborative role in the shared decision-making process, while similar proportions of caregivers favored active and collaborative roles. CONCLUSION: Our study demonstrates that both patients and caregivers consider cost seriously when making treatment decisions. Furthermore, as patient and caregiver preferences may differ, there are implications for treatment selection and counseling, especially in cultures where caregivers have more prominent roles in treatment planning.

High-dose methotrexate is effective for prevention of isolated CNS relapse in diffuse large B cell lymphoma.

The role of central nervous system (CNS) prophylaxis with high-dose methotrexate (HDMTX) in DLBCL is controversial. In this retrospective study, we evaluated the efficacy of prophylactic HDMTX on isolated CNS relapse, concomitant CNS and systemic relapse, systemic relapse, and survival outcomes in 226 patients with newly diagnosed DLBCL and high-risk CNS International Prognostic Index (CNS-IPI) score treated with RCHOP. The three-year risk of isolated CNS relapse was significantly lower in patients who received HDMTX, at 3.1% compared to 14.6% (P = 0.032) in those who did not. However, neither concomitant CNS-systemic relapse rates, systemic relapse rates, nor three-year PFS and OS were significantly different between treatment groups in multivariable analysis. Among propensity score-matched patients (N = 102), HDMTX was also associated with significantly lower isolated CNS relapse rates (HR 0.06, 95% CI 0.004-0.946, P = 0.046). HDMTX was well tolerated with manageable toxicities when given at a dose of 3 g/m2 by day 3 of RCHOP chemotherapy. Using propensity score matching and multivariable regression to yield treatment groups with well-balanced covariates, we showed that prophylactic HDMTX improved isolated CNS relapse rates but did not decrease concomitant CNS-systemic relapse rates, systemic relapse rates, or improve survival outcomes.

Qualitative Study of Factors Affecting Patient, Caregiver and Physician Preferences for Treatment of Myeloma and Indolent Lymphoma.

INTRODUCTION: The number of treatment options for myeloma and indolent lymphoma are expanding at an exponential rate, with few direct head-to-head comparisons on which to base efficacy measures. We sought to understand how patients, their caregivers and physicians weigh treatment characteristics in order to come to a decision on which treatment option to pursue. METHODS: Patients, their caregivers and physicians were recruited and interviewed until data saturation was reached. A qualitative, thematic analysis was done to identify themes important to each stakeholder. RESULTS: We found that, while all three groups valued efficacy the most, the consideration of other secondary characteristics of the treatment, such as cost, toxicity and logistical issues all differed subtly between the different groups. Patients valued minimising cost and toxicity, even at small trade-offs in efficacy. Caregivers and physicians valued efficacy foremost. CONCLUSION: Acknowledging and managing these differences is paramount because they influence shared decision-making and may affect patient outcomes in the short term, as well as their more general well-being in the long term.

Letting the cat out of the bag: shifting practices of cancer disclosure in Singapore.

INTRODUCTION: Communication between patients and physicians is crucial in the disclosure of cancer diagnosis. Although westernisation of Asian societies has resulted in increased awareness of patient autonomy, the family continues to play an important influencing role in the disclosure process. Therefore, in this study, we aimed to characterise the experience of physicians with the disclosure of cancer diagnosis in a westernised Asian population. METHODS: Oncologists at a tertiary hospital were approached to participate in this study. Information pertaining to the extent and approach to disclosure was collated. Logistic regression analysis was performed to characterise factors pertaining to the willingness of physicians to fully disclose a diagnosis of cancer. RESULTS: In all, 25 oncologists (mean age 38 years; 72% men) responded to the survey. A majority of oncologists disclosed a cancer diagnosis directly to the patient over the first few visits. The main reason behind partial or non-disclosure was family objection. Ordinal logistic regression analysis showed that family resistance was the only significant predictor of reluctance to disclose a cancer diagnosis (p = 0.01). CONCLUSION: In this pilot study, contrary to previous reports, we found that oncologists were more likely to disclose a diagnosis of cancer to the patient first, that they do not accede fully to the family's request for non-disclosure and that family resistance was the only significant predictor of reluctance to disclose a diagnosis of cancer.