Increased risk of citrate reactions in patients with multiple myeloma during peripheral blood stem cell leukapheresis

Apheresis collection of mononuclear cells for chimeric-antigen receptor therapies

Collections of lymphocytes to be genetically modified to treat hematologic malignancies have seen a dramatic increase over the last few years as commercial products have been approved. Reports of new products in development that can possibly treat solid organ malignancies represent a massive change in the field. Apheresis is at the center of the collection of cells for the manufacture of these chimeric-antigen receptor therapy products. The expansion of these collections represents one of the areas of apheresis procedures growth. This review will summarize concepts important to this type of collection and variables that need to be optimized to obtain desired cell yields while increasing patients' safety.

Prevalence of baseline hypocalcemia and symptomatic hypocalcemia during leukapheresis

Symptoms of hypocalcemia are reported in up to 50% of patients undergoing leukapheresis procedures. There is no set standard of practice for administering calcium supplementation in the prevention or treatment of hypocalcemia symptoms. The goal of this descriptive, retrospective study was to determine the prevalence of baseline hypocalcemia and symptomatic hypocalcemia during leukapheresis with acid citrate dextrose solution A and to identify patient characteristics associated with symptomatic hypocalcemia. Three percent of patients were found to have hypocalcemia before leukapheresis with 35% experiencing hypocalcemia symptoms during leukapheresis. Older age, higher albumin levels, and longer procedure time were associated with increased risk of hypocalcemia symptoms.

A nomogram prediction of citrate reaction during mononuclear cell collection in solid tumor patients

PURPOSE

Citrate reaction is one of the main adverse events in peripheral blood mononuclear cell (MNC) collection. The aim of this study was to elucidate the risk factors for citrate reaction in patients with advanced solid tumor collection and to construct a nomogram to predict the risk.

METHODS

One hundred forty-eight patients with advanced solid tumor who underwent peripheral blood MNC collection in our hospital between January 2021 to December 2021 were selected. The general data, creatinine level before collection, Ca²⁺ concentration before collection, absolute value of monocyte lymphocytes before collection, circulating blood volume, anticoagulant dosage, and blood collection duration were included in Logistic regression analysis to identify the risk factors of citrate reaction. According to the results of the multivariate logistic model, nomogram was established and receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of the model.

RESULTS

Among the 148 solid tumor patients, 35 patients (23.6%) of the 148 patients developed citrate reaction. Multivariate analysis showed that the risk factors for citrate reaction in the process of collection included sex (odds ratio [OR] = 6.718; 95% confidence interval [95% CI]: 2.191-20.594, P = .001), age (OR = 0.957; 95% CI: 0.921-0.996, P = .03), and processed circulating blood volume (OR = 1.001; 95% CI: 1.000-1.002, P = .01). Logistic regression can analyze independent risk factors and establish risk prediction model. The predictive performance of the model is good, and the area under ROC curve is 0.799.

CONCLUSIONS

The MNC collection process is safe. The incidence of citrate reaction in the collection of peripheral blood MNCs from patients with advanced solid tumor is related to the age, gender, and processed circulating blood volume of patients. The nomogram can be used to assess a patient's risk of citrate reaction.