Evaluation of acute toxicities associated with autologous peripheral blood progenitor cell reinfusion in patients undergoing high-dose chemotherapy

Trehalose in Biomedical Cryopreservation-Properties, Mechanisms, Delivery Methods, Applications, Benefits, and Problems

Cells and tissues are the foundation of translational medicine. At present, one of the main technological obstacles is their preservation for long-term usage while maintaining adequate viability and function. Optimized storage techniques must be developed to make them safer to use in the clinic. Cryopreservation is the most common long-term preservation method to maintain the vitality and function of cells and tissues. But, the formation of ice crystals in cells and tissues is considered to be the main mechanism that could harm cells and tissues during freezing and thawing. To reduce the formation of ice crystals, cryoprotective agents (CPAs) must be added to the cells and tissues to achieve the cryoprotective effect. However, conventional cryopreservation of cells and tissues often needs to use toxic organic solvents as CPAs. As a result, cryopreserved cells and tissues may need to go through a time-consuming washing process to remove CPAs for further applications in translational medicine, and multiple valuable cells are potentially lost or killed. Currently, trehalose has been researched as a nontoxic CPA due to its cryoprotective ability and stability during cryopreservation. Nevertheless, trehalose is a nonpermeable CPA, and the lack of an effective intracellular trehalose delivery method has become the main obstacle to its use in cryopreservation. This article illustrated the properties, mechanisms, delivery methods, and applications of trehalose, summarized the benefits and limits of trehalose, and summed up the findings and research direction of trehalose in biomedical cryopreservation.

Synthesis of Poly(2-(methylsulfinyl)ethyl methacrylate) via Oxidation of Poly(2-(methylthio)ethyl methacrylate): Evaluation of the Sulfoxide Side Chain on Cryopreservation

Conventional cryopreservation solutions rely on the addition of organic solvents such as DMSO or glycerol, but these do not give full recovery for all cell types, and innovative cryoprotectants may address damage pathways which these solvents do not protect against. Macromolecular cryoprotectants are emerging, but there is a need to understand their structure-property relationships and mechanisms of action. Here we synthesized and investigated the cryoprotective behavior of sulfoxide (i.e., "DMSO-like") side-chain polymers, which have been reported to be cryoprotective using poly(ethylene glycol)-based polymers. We also wanted to determine if the polarized sulfoxide bond (S⁺O^- character) introduces cryoprotective effects, as this has been seen for mixed-charge cryoprotective polyampholytes, whose mechanism of action is not yet understood. Poly(2-(methylsulfinyl)ethyl methacrylate) was synthesized by RAFT polymerization of 2-(methylthio)ethyl methacrylate and subsequent oxidation to sulfoxide. A corresponding N-oxide polymer was also prepared and characterized: (poly(2-(dimethylamineoxide)ethyl methacrylate). Ice recrystallization inhibition assays and differential scanning calorimetry analysis show that the sulfoxide side chains do not modulate the frozen components during cryopreservation. In cytotoxicity assays, it was found that long-term (24 h) exposure of the polymers was not tolerated by cells, but shorter (30 min) incubation times, which are relevant for cryopreservation, were tolerated. It was also observed that overoxidation to the sulfone significantly increased the cytotoxicity, and hence, these materials require a precision oxidation step to be deployed. In suspension cell cryopreservation investigations, the polysulfoxides did not increase cell recovery 24 h post-thaw. These results show that unlike hydrophilic backboned polysulfides, which can aid cryopreservation, the installation of the sulfoxide group onto a polymer does not necessarily bring cryoprotective properties, highlighting the challenges of developing and discovering macromolecular cryoprotectants.

The value of the post-thaw CD34+ count with and without DMSO removal in the setting of autologous stem cell transplantation

BACKGROUND

CD34+ cell count correlates with engraftment potency after autologous stem cell transplantation. Assessment of CD34+ mainly occurs after apheresis and before cryopreservation with dimethyl sulfoxide (DMSO). The influence of postthaw CD34+ cell numbers over time to engraftment is not well studied, and determination of postthaw CD34+ cell counts is challenging for a variety of reasons. The aim of this retrospective study was to systematically assess the value of postthaw CD34+ cell counts in autologous grafts with and without DMSO removal.

STUDY DESIGN AND METHODS

Between January 2008 and December 2015, 236 adult patients underwent a total of 292 autologous stem cell transplantations. Median age at transplantation was 56 years, and the main indication was multiple myeloma (60%). DMSO removal was done in 96 grafts (33%), either by centrifugation or by Sepax method.

RESULTS

Patients receiving grafts containing DMSO showed a significantly faster platelet (p = 0.02) and RBC (p = 0.001) engraftment. DMSO removal was not associated with fewer infusion-related adverse events. We observed a good correlation between CD34+ cell count after apheresis and CD34+ cell count after thawing/washing (r = 0.931). Ninety grafts (31%) showed a significant loss of viable CD34+ cells, which translated into a delayed engraftment.

CONCLUSION

DMSO removal was associated with delayed platelet and RBC engraftment without preventing adverse events. CD34+ cell enumeration after thawing remains difficult to perform, but grafts showing higher cell loss during cryopreservation and thawing are associated with slower engraftment. Prospective studies on the role of DMSO removal and postthaw CD34+ enumeration using defined protocols are needed.

The influence of cell concentration at cryopreservation on neutrophil engraftment after autologous peripheral blood stem cell transplantation

BACKGROUND

Peripheral blood stem cell concentrations are traditionally adjusted to 20-40 × 106 leukocytes/mL prior to freezing. This low cell concentration at cryopreservation implies larger volumes with more dimethyl sulfoxide being used, and higher cost and toxicity at the time of transplant. Higher cell concentrations have been reported but this is not widely accepted. Moreover, the influence of cell concentration on engraftment has not been well documented. Therefore, this study retrospectively analyzed the influence of peripheral blood stem cell concentration at freezing on engraftment after autologous hematopoietic stem cell transplantation.

METHOD

Leukapheresis products were plasma-depleted and cryopreserved with 5% dimethyl sulfoxide, 6% hydroxyethylamide solution and 4% albumin in a -80 °C freezer. Individual patient data from hospital records were reviewed.

RESULTS

Fifty consecutive patients with oncological diseases underwent 88 leukaphereses. Median age was six years (range: 1-32 years) and median weight was 19 kg (range: 8-94 kg). Median leukocyte concentration was 109 × 106/mL at collection and 359 × 106 (range: 58-676 × 106) at freezing with 78% viability (range: 53-95%); leukocyte recovery after thawing was 95% (range: 70-100%). In multivariate analysis, cell concentration (p-value = 0.001) had a negative impact on engraftment. Patients infused with bags frozen with <200 × 106 leukocytes/mL engrafted after a median of nine days (range: 8-12 days), 200-400 × 106 leukocytes/mL after 11 days (range: 9-20 days); 400-600 × 106 leukocytes/mL after 12 days (range: 8-19 days) and with cell concentrations >600 × 106 leukocytes/mL, engraftment was after 14 days (range: 13-22 days).

CONCLUSION

In patients with adequate CD34 cell collections, total leukocyte concentrations of 282 × 106/mL, freezing with 5% dimethyl sulfoxide and 6% hydroxyethylamide solution without a controlled-rate freezer, and storing cells at -80 °C yielded excellent engraftment. Further increases in cell concentration may delay engraftment, without affecting safety.

Neurologic complications after allogeneic hematopoietic stem cell transplantation: risk factors and impact

Neurologic complications (NCs) may be a significant source of morbidity and mortality after hematopoietic cell transplantation (HCT). We performed a retrospective study of 263 consecutive patients undergoing allogeneic HCT for hematological malignancies to determine the incidence, risk factors and clinical impact of NCs in the first 5 years after HCT. We determined the incidence of central nervous system (CNS) infection, intracranial hemorrhage, ischemic stroke, metabolic encephalopathy, posterior reversal encephalopathy syndrome, seizure and peripheral neuropathy. In all, 50 patients experienced 63 NCs-37 early (⩽day +100), 21 late (day +101 to 2 years) and 5 very late (2 to 5 years). The 1- and 5-year cumulative incidences of all NCs were 15.6% and 19.2%, respectively, and of CNS complication (CNSC; all of the above complications except peripheral neuropathy) were 12.2 and 14.5%. Risk factors for CNSC were age (hazard ratio (HR)=1.06 per year, P=0.0034), development of acute GvHD grade III-IV (HR=2.78, P=0.041), transfusion-dependent thrombocytopenia (HR=3.07, P=0.025) and delayed platelet engraftment (>90th centile; HR=2.77, P=0.043). CNSCs negatively impacted progression-free survival (HR=2.29, P=0.0001), overall survival (HR=2.63, P<0.0001) and non-relapse mortality (HR=8.51, P<0.0001). NCs after HCT are associated with poor outcomes, and usually occur early after HCT.

Hematopoietic SCT with cryopreserved grafts: adverse reactions after transplantation and cryoprotectant removal before infusion

Transplantation of hematopoietic stem cells (HSCs) has been successfully developed as a part of treatment protocols for a large number of clinical indications, and cryopreservation of both autologous and allogeneic sources of HSC grafts is increasingly being used to facilitate logistical challenges in coordinating the collection, processing, preparation, quality control testing and release of the final HSC product with delivery to the patient. Direct infusion of cryopreserved cell products into patients has been associated with the development of adverse reactions, ranging from relatively mild symptoms to much more serious, life-threatening complications, including allergic/gastrointestinal/cardiovascular/neurological complications, renal/hepatic dysfunctions, and so on. In many cases, the cryoprotective agent (CPA) used-which is typically dimethyl sulfoxide (DMSO)-is believed to be the main causal agent of these adverse reactions and thus many studies recommend depletion of DMSO before cell infusion. In this paper, we will briefly review the history of HSC cryopreservation, the side effects reported after transplantation, along with advances in strategies for reducing the adverse reactions, including methods and devices for removal of DMSO. Strategies to minimize adverse effects include medication before and after transplantation, optimizing the infusion procedure, reducing the DMSO concentration or using alternative CPAs for cryopreservation and removing DMSO before infusion. For DMSO removal, besides the traditional and widely applied method of centrifugation, new approaches have been explored in the past decade, such as filtration by spinning membrane, stepwise dilution-centrifugation using rotating syringe, diffusion-based DMSO extraction in microfluidic channels, dialysis and dilution-filtration through hollow-fiber dialyzers and some instruments (CytoMate, Sepax S-100, Cobe 2991, microfluidic channels, dilution-filtration system, etc.) as well. However, challenges still remain: development of the optimal (fast, safe, simple, automated, controllable, effective and low cost) methods and devices for CPA removal with minimum cell loss and damage remains an unfilled need.

A randomised, placebo-controlled, first-in-human study of a novel clade C therapeutic peptide vaccine administered ex vivo to autologous white blood cells in HIV infected individuals

Background

Preclinical studies of overlapping 15mer peptides, spanning SIV, SHIV or HIV, pulsed on autologous PBMC ex vivo have demonstrated high level, virus-specific T cell responses and viral suppression in non-human primates (NHP). Opal-HIV-Gag(c) consists of 120 synthetic 15mer peptides spanning Clade C, consensus Gag, manufactured to current good manufacturing practice; having been evaluated in a good laboratory practice toxicology study in Macaca mulatta. We evaluated the safety and preliminary immunogenicity of such peptides administered intravenously after short-duration ex vivo incubation, to HIV-positive adults on suppressive antiretroviral therapy.

Methods and Findings

A first-in-human, placebo-controlled, double-blind, dose escalation study was conducted. Twenty-three patients with virus suppressed by antiretroviral therapy were enrolled in four groups 12 mg (n = 6), 24 mg (n = 6), 48 mg (n = 2) or matching placebo (n = 8). Treatment was administered intravenously after bedside enrichment of 120 mL whole blood for white cells using a closed system (Sepax S-100 device), with ex vivo peptide admixture (or diluent alone) and 37°C incubation for one hour prior to reinfusion. Patients received 4 administrations at monthly intervals followed by a 12-week observation post-treatment. Opal-HIV-Gag(c) was reasonably tolerated at doses of 12 and 24 mg. There was an increased incidence of temporally associated pyrexia, chills, and transient/self-limiting lymphopenia in Opal-HIV-Gag(c) recipients compared to placebo. The study was terminated early, after two patients were recruited to the 48 mg cohort; a serious adverse event of hypotension, tachycardia secondary to diarrhoea occurred following a single product administration. An infectious cause for the event could not be identified, leaving the possibility of immunologically mediated product reaction.

Conclusions

A serious, potentially life-threatening event of hypotension led to early, precautionary termination of the study. In the absence of a clearly defined mechanism or ability to predict such occurrence, further development of Opal-HIV-Gag(c) will not be undertaken in the current form.

Registration

ClinicalTrials.gov NCT01123915; EudraCT: 2008-005142-23

Manufacturing and banking of mesenchymal stem cells

INTRODUCTION

Mesenchymal stem cells (MSC) and MSC-like cells hold great promise and offer many advantages for developing effective cellular therapeutics. Current trends indicate that the clinical application of MSC will continue to increase markedly. For clinical applications, large numbers of MSC are usually required, ideally in an off-the-shelf format, thus requiring extensive MSC expansion ex vivo and subsequent cryopreservation and banking.

AREAS COVERED

To exploit the full potential of MSC for cell-based therapies requires overcoming significant cell-manufacturing, banking and regulatory challenges. The current review will focus on the identification of optimal cell source for MSC, the techniques for production scale-up, cryopreservation and banking and the regulatory challenges involved.

EXPERT OPINION

There has been considerable success manufacturing and cryopreserving MSC at laboratory scale. Surprisingly little attention, however, has been given to translate these technologies to an industrial scale. The development of cost-effective advanced technologies for producing and cryopreserving commercial-scale MSC is important for successful clinical cell therapy.

Hydroxyethylstarch in cryopreservation - mechanisms, benefits and problems

As the progress of regenerative medicine places ever greater attention on cryopreservation of (stem) cells, tried and tested cryopreservation solutions deserve a second look. This article discusses the use of hydroxyethyl starch (HES) as a cryoprotectant. Charting carefully the recorded uses of HES as a cryoprotectant, in parallel to its further clinical use, indicates that some HES subtypes are a useful supplement to dimethysulfoxide (DMSO) in cryopreservation. However, we suggest that the most common admixture ratio of HES and DMSO in cryoprotectant solutions has been established by historical happenstance and requires further investigation and optimization.

High white blood cell concentration in the peripheral blood stem cell product can induce seizures during infusion of autologous peripheral blood stem cells

Seizures as a complication of the infusion of autologous peripheral blood stem cells (PBSC) are rare. Seizures during infusion of autologous PBSC in 3 of our patients prompted us to review our cell therapy and cytapheresis protocols and procedures. We retrospectively analyzed 159 adult patients collected between January 2006 and July 2009. Patients were collected on either the COBE Spectra (Caridian BCT, Lakewood, CO) cell separator (n = 85) or Fresenius AS (Fresenius Kabi AG, Bad Homburg, Germany) 104 cell separator (n = 74) and mobilized with granulocyte-colony stimulating factor (G-CSF) alone (n = 47), G-CSF and Plerixafor (n = 36), or G-CSF and chemotherapy (n = 76). Patient characteristics (including age, weight, number of collections, volume processed, disease type, and mobilization strategy) did not differ significantly between the COBE and Fresenius cohorts, and adverse effects from infusion were similar except for 3 of 159 patients who experienced seizures upon infusion of PBSC; all 3 were collected on the COBE and had PBSC product white blood cell (WBC) counts of 590 × 10(3)/μL or above. We prospectively correlated WBC counts midcollection, with final WBC counts to identify products with high WBC concentration during cytapheresis. Fifty-one patients had 66 cytapheresis procedures using the COBE, with WBC counts midway and at the end of collection of 287 × 10(3) ± 150/μL and 273 × 10(3) ± 144/μL, respectively. Mid-WBC therefore correlated with WBC at the end of the collection. Finally, we prospectively collected mid-WBC from 65 patients who underwent 80 PBSC collections between June 2009 and January 2010 to identify products with midcollection WBC concentration >450 × 10(3)/μL. In those cases, additional autologous plasma was collected at the time of collection to dilute the final product before cryopreservation. Patients who received diluted products experienced no delays in engraftment and no additional seizure episodes occurred.

Pleuropulmonary Changes Induced by Drugs in Patients with Hematologic Diseases

Patients with hematologic diseases who are being treated with therapy drugs, or receive radiation therapy or blood transfusions may develop a host of potentially fatal infectious and noninfectious pulmonary complications [1]. The increased complexity of multimodality and high-dose treatment regimens with the intended benefit of augmented antineoplastic efficacy and prolonged disease-free survival, the use of a panel of novel drugs to treat malignant and nonmalignant hematologic conditions (e.g., azacytidine, bortezomib, cladribine, dasatinib, fludarabine, imatinib, lenalidomide, rituximab, and thalidomide), total body irradiation (TBI) and hematopietic stem cell transplantation (HSCT) have increased the incidence of severe sometimes life-threatening pulmonary complications.

The lollipop with strawberry aroma may be promising in reduction of infusion-related nausea and vomiting during the infusion of cryopreserved peripheral blood stem cells

Nausea and vomiting during the infusion of cryopreserved peripheral blood stem cells (PBSC) are common. The aim of this study was to explore the effect of lollipop with strawberry aroma on the infusion-related nausea and vomiting of cryopreserved autologous PBSCs. We compared 2 groups of adult patients receiving lollipop with strawberry aroma during cryopreserved PBSC infusions or not to assess the incidences of nausea and vomiting occurring during infusions. All patients received granisetron 3 mg i.v. twice a day, and lorazepam 1 mg every 4 hours orally for prophylaxis of the nausea and vomiting during conditioning phase and infusion day. Before infusion, all patients were premedicated with pheniramine maleate 45.5 mg i.v. and paracetamol 500 mg orally. The patients had no evidence of nausea or vomiting prior to cryopreserved PBSC infusions. The patients with ongoing nausea or vomiting owing to conditioning regimens and/or receiving additional antiemetics were excluded from the study. One hundred fifty-eight patients who consecutively underwent autologous stem cell transplantation for malignancy were included in the study. The first 110 patients (median age: 42.5, range: 17-75) were observed for the infusion related adverse effects only. The consecutive 48 patients (median age: 48, range: 18-80) were given a lollipop with strawberry aroma during cryopreserved PBSC infusions and observed for the infusion-related adverse effects. The 2 groups were comparable with respect to age, sex, diagnosis, stem cell collection methods, conditioning regimens administered, total mononuclear cell dose infused, number of total nucleated cells (TNCs) infused, number of CD34+ cells infused, number of bags infused, total volume infused, amount of dimethylsulfoxide (DMSO), and infusion rate. Patients who received a lollipop with a strawberry aroma during infusions had significantly less nausea (6.3%, n = 3 versus 21.8%, n = 24, P = .02) and vomiting (2%, n = 1 versus 13.6%, n = 15, P = .04) than the ones who did not (observation only group). Other infusion-related adverse events were as follows; hypoxia, cough, dyspnea, abdominal cramping, tachycardia, hiccup, fever, chills, chest pain, hypotension, hypertension, agitation, sore throat, and arrhythmia. Incidences of each of these adverse events were <5% in both groups and were comparable. The use of a lollipop with a strawberry aroma during infusion of cryopreserved autologous PBSCs may be promising in reduction of infusion-related nausea and vomiting, with an easy administration at a very cheap cost.

Occurrence and severity of adverse events after autologous hematopoietic progenitor cell infusion are related to the amount of granulocytes in the apheresis product

BACKGROUND

Adverse events (AEs) after hematopoietic progenitor cell (HPC) infusion are rare but might be life-threatening. These reactions have traditionally been associated with the amount of infused cryoprotectant, but persistence of such events after dimethyl sulfoxide (DMSO) depletion has questioned this assumption.

STUDY DESIGN AND METHODS

The incidence of AEs on a cohort of 460 patients (490 HPC infusions) undergoing autologous DMSO-reduced HPC transplantation was prospectively evaluated. HPCs were collected from adult patients with various hematologic or solid malignancies. After quality control (QC) on fresh apheresis products and subsequent cryopreservation, HPC grafts were thawed and washed at the cell therapy facility. QC was performed on each graft after washing, and clinical data were collected for each infusion.

RESULTS

AEs were reported in 66 cases (13.5%) and were graded according to the NCI-CTC scale from 1 to 4. Although none of the factors associated with patient characteristics or infusion procedure were different between the two groups (no AE vs. occurrence of AE), it was found that the absolute number of granulocytes measured before freezing was considerably higher in the AE group. Furthermore, within this group, there was a strong correlation between the amount of granulocytes and the grading of the reaction.

CONCLUSION

This survey demonstrates that AEs occurring in the setting of DMSO-reduced HPC grafts are directly related to the amount of granulocytes and thus emphasizes the need for high-quality apheresis products so as to improve the safety of HPC infusion.

Neurotoxicity upon infusion of dimethylsulfoxide-cryopreserved peripheral blood stem cells in patients with and without pre-existing cerebral disease

OBJECTIVE

Toxicity related to the infusion of dimethylsulfoxide (DMSO)-cryopreserved peripheral blood stem cells (DMSO-PBSC) mainly comprises cardiovascular events. Fatal neurotoxicity has been reported in a few cases. DMSO represents the putative causative agent of such rare toxicities and elaborate strategies to replace DMSO would benefit from the identification of predisposing factors for DMSO-related toxicities.

METHODS

Here, we report on DMSO-related neurotoxicity in a series of patients (n = 51) receiving DMSO-PBSC. The analyzed patient-series included eight patients with pre-existing cerebral disease, partially with a history of epileptic seizures.

RESULTS

Neurotoxicity was observed in only one patient who suffered from a generalized tonic seizure upon infusion of DMSO-PBSC and for which the clinical course is reported herein. No neurotoxicity was observed in the group of patients with pre-existing neurological disease. Furthermore, no neurotoxicity was observed in patients who received particularly large volumes of DMSO. In all patients, mild non-neurological side effects occurred but besides the reported seizure no other severe adverse events were observed upon PBSC-infusion.

CONCLUSIONS

To our knowledge, this is the first report addressing the identification of predisposing factors for DMSO-related neurotoxicty. We conclude that infusion of DMSO-PBSC can be performed safely in patients with pre-existing cerebral disease despite the rare occurrence of severe neurotoxicity. Retrospective multicenter studies are warranted to identify patients who would benefit from elaborate methods of DMSO-replacement.

Cryopreservation of hematopoietic stem cells

Stem cell transplantation represents a critical approach for the treatment of many malignant and non-malignant diseases. The foundation for these approaches is the ability to cryopreserve marrow cells for future use. This technique is routinely employed in all autologous settings and is critical for cord blood transplantation. A variety of cryopreservatives have been used with multiple freezing and thawing techniques as outlined in the later chapters. Freezing efficiency has been proven repeatedly and the ability of long-term stored marrow to repopulate has been established. Standard approaches outlined here are used in many labs as the field continues to evolve.

Neurologic complications of bone marrow, stem cell, and organ transplantation in patients with cancer

Bone marrow and peripheral blood stem cell transplantation are part of the standard of care for a variety of oncologic and non-oncologic disorders and are associated with a large spectrum of neurologic complications. These complications may arise at any time during and after the transplantation process, especially in subjects requiring chronic immunosuppression, and are most frequently related to infections, cerebrovascular or metabolic events, and toxicity from radiation or chemotherapy. Due to the unique circumstances and treatments surrounding each step in the transplantation process, there is a higher incidence of some neurologic complications during discrete time periods. Being aware of the temporal relationship of the neurologic disorder within the transplantation process can therefore facilitate diagnosis and institution of appropriate therapy. Neurologic complications after solid organ transplantation are often due to similar mechanisms as in patients after bone marrow and stem cell transplantation although there are several complications unique to these patients such as transmission of infectious agents by the donated organ. For these patients, the clinician needs to have a high index of suspicion that the neurologic problem is related to the transplant.

Variation in dimethyl sulfoxide use in stem cell transplantation: a survey of EBMT centres

The cryoprotectant dimethyl sulfoxide (DMSO) is known to have toxic side effects, yet guidelines for its use in stem cell transplantation do not exist. To assess current practice in the use of DMSO and the incidence of DMSO-related complications, a single page questionnaire was mailed to 444 EBMT centres involved in autologous transplantation. The responses from 97 centres showed a wide variation in practice between transplant units regarding the concentration of DMSO used, daily DMSO dose restriction and the use of cell washing. The overall incidence of DMSO toxicity was approximately one in 70 transplants and most cases were cardiovascular and respiratory in nature. There was a trend to reduced complication rates in centres using lower concentrations of DMSO or washing cells prior to return. A large-scale prospective study of the strategies for reduction in exposure to DMSO and reduction in toxic effects is required before guidelines in the use of DMSO in stem cell cryopreservation can be promulgated.

Myocardial injury revealed by plasma troponin I in breast cancer treated with high-dose chemotherapy

BACKGROUND

High-dose chemotherapy (HDC) has been widely utilized in high-risk breast cancer, but it may induce cardiac toxicity. Cardiac dysfunction may become evident weeks or months after HDC and, to date, no early markers of myocardial injury that are able to predict late ventricular impairment are available. We investigated the role of plasma troponin I (TnI) in this setting.

PATIENTS AND METHODS

We measured TnI plasma concentration after HDC in 211 high-risk breast cancer women (46 +/- 11 years, mean +/- SD). According to TnI value (< 0.5 or > or = 0.5 ng/ml), patients were allocated into a troponin positive (TnI+; n = 70) and a troponin negative (TnI-; n = 141) group. All patients underwent left ventricular ejection fraction (LVEF, Echo) examination during the following 12 months.

RESULTS

LVEF progressively decreased in the TnI+ group but not in the TnI- group. In TnI+ patients a close relationship between the TnI increase, as well as the number of positive TnI assays, and the maximal LVEF decrement, was found (r = -0.92, P < 0.0001 and r = -0.93, P < 0.0001, respectively).

CONCLUSIONS

In our population, the elevation of TnI soon after HDC accurately predicts the development of future LVEF depression. In this setting, TnI can be considered a sensitive and reliable marker of myocardial damage with relevant clinical and prognostic implications.