Hormonal stimulation reduces numbers and impairs function of human uterine natural killer cells during implantation

STUDY QUESTION

How does an altered maternal hormonal environment, such as that seen during superovulation with gonadotropins in ART, impact human uterine immune cell distribution and function during the window of implantation?

SUMMARY ANSWER

Hormonal stimulation with gonadotropins alters abundance of maternal immune cells including uterine natural killer (uNK) cells and reduces uNK cell ability to promote extravillous trophoblast (EVT) invasion.

WHAT IS KNOWN ALREADY

An altered maternal hormonal environment, seen following ART, can lead to increased risk for adverse perinatal outcomes associated with disordered placentation. Maternal immune cells play an essential role in invasion of EVTs, a process required for proper establishment of the placenta, and adverse perinatal outcomes have been associated with altered immune cell populations. How ART impacts maternal immune cells and whether this can in turn affect implantation and placentation in humans remain unknown.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study was carried out between 2018 and 2021 on 51 subjects: 20 from natural cycles 8 days after LH surge; and 31 from stimulated IVF cycles 7 days after egg retrieval.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Endometrial biopsies and peripheral blood samples were collected during the window of implantation in subjects with regular menstrual cycles or undergoing superovulation. Serum estradiol and progesterone levels were measured by chemiluminescent competitive immunoassay. Immune cell populations in blood and endometrium were analyzed using flow cytometry. uNK cells were purified using fluorescence-activated cell sorting and were subjected to RNA sequencing (RNA-seq). Functional changes in uNK cells due to hormonal stimulation were evaluated using the implantation-on-a-chip (IOC) device, a novel bioengineered platform using human primary cells that mimics early processes that occur during pregnancy in a physiologically relevant manner. Unpaired t-tests, one-way ANOVA, and pairwise multiple comparison tests were used to statistically evaluate differences.

MAIN RESULTS AND THE ROLE OF CHANCE

Baseline characteristics were comparable for both groups. As expected, serum estradiol levels on the day of biopsy were significantly higher in stimulated (superovulated) patients (P = 0.0005). In the setting of superovulation, we found an endometrium-specific reduction in the density of bulk CD56+ uNK cells (P < 0.05), as well as in the uNK3 subpopulation (P = 0.025) specifically (CD103+ NK cells). In stimulated samples, we also found that the proportion of endometrial B cells was increased (P < 0.0001). Our findings were specific to the endometrium and not seen in peripheral blood. On the IOC device, uNK cells from naturally cycling secretory endometrium promote EVT invasion (P = 0.03). However, uNK cells from hormonally stimulated endometrium were unable to significantly promote EVT invasion, as measured by area of invasion, depth of invasion, and number of invaded EVTs by area. Bulk RNA-seq of sorted uNK cells from stimulated and unstimulated endometrium revealed changes in signaling pathways associated with immune cell trafficking/movement and inflammation.

LIMITATIONS, REASONS FOR CAUTION

Patient numbers utilized for the study were low but were enough to identify significant overall population differences in select immune cell types. With additional power and deeper immune phenotyping, we may detect additional differences in immune cell composition of blood and endometrium in the setting of hormonal stimulation. Flow cytometry was performed on targeted immune cell populations that have shown involvement in early pregnancy. A more unbiased approach might identify changes in novel maternal immune cells not investigated in this study. We performed RNA-seq only on uNK cells, which demonstrated differences in gene expression. Ovarian stimulation may also impact gene expression and function of other subsets of immune cells, as well as other cell types within the endometrium. Finally, the IOC device, while a major improvement over existing in vitro methods to study early pregnancy, does not include all possible maternal cells present during early pregnancy, which could impact functional effects seen. Immune cells other than uNK cells may impact invasion of EVTs in vitro and in vivo, though these remain to be tested.

WIDER IMPLICATIONS OF THE FINDINGS

These findings demonstrate that hormonal stimulation affects the distribution of uNK cells during the implantation window and reduces the proinvasive effects of uNK cells during early pregnancy. Our results provide a potential mechanism by which fresh IVF cycles may increase risk of disorders of placentation, previously linked to adverse perinatal outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

Research reported in this publication was supported by the University of Pennsylvania University Research Funding (to M.M.), the Eunice Kennedy Shriver National Institute of Child Health and Human Development (P50HD068157 to M.M., S.S., and S.M.), National Center for Advancing Translational Sciences of the National Institutes of Health (TL1TR001880 to J.K.), the Institute for Translational Medicine and Therapeutics of the Perelman School of Medicine at the University of Pennsylvania, the Children's Hospital of Philadelphia Research Institute (to S.M.G.), and the National Institute of Allergy and Infectious Diseases (K08AI151265 to S.M.G.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Potential antiviral effects of pantethine against SARS-CoV-2

SARS-CoV-2 interacts with cellular cholesterol during many stages of its replication cycle. Pantethine was reported to reduce total cholesterol levels and fatty acid synthesis and potentially alter different processes that might be involved in the SARS-CoV-2 replication cycle. Here, we explored the potential antiviral effects of pantethine in two in vitro experimental models of SARS-CoV-2 infection, in Vero E6 cells and in Calu-3a cells. Pantethine reduced the infection of cells by SARS-CoV-2 in both preinfection and postinfection treatment regimens. Accordingly, cellular expression of the viral spike and nucleocapsid proteins was substantially reduced, and we observed a significant reduction in viral copy numbers in the supernatant of cells treated with pantethine. In addition, pantethine inhibited the infection-induced increase in TMPRSS2 and HECT E3 ligase expression in infected cells as well as the increase in antiviral interferon-beta response and inflammatory gene expression in Calu-3a cells. Our results demonstrate that pantethine, which is well tolerated in humans, was very effective in controlling SARS-CoV-2 infection and might represent a new therapeutic drug that can be repurposed for the prevention or treatment of COVID-19 and long COVID syndrome.

106 A Whole Hospital Delirium Audit with 20 Week Follow-Up

Introduction

Delirium is a common manifestation of acute illness, characterised by fluctuating changes in mental state. Its aetiologies and presentations are diverse. This can lead to underdiagnosis. We screened all adult inpatients at Barnet Hospital for delirium. 20 weeks follow-up data was collected, including mortality and admission to institutional care.

Methods

The 4AT and Clinical Frailty Score (CFS) were recorded for every adult inpatient (n = 220) in Barnet Hospital on 13/03/2019. Hospital notes were reviewed to establish whether delirium assessments were performed during admission. Electronic records were used to establish length of stay, discharge destination, mortality and readmission rate over 20 weeks.

Results

30% (n = 65) of inpatients had possible delirium (4AT score ≥ 4). Delirium was more common in older, frailer patients (Table 1). Most patients with delirium were under the care of geriatric (40%) or acute medicine (26%). Only gastroenterology and gynaecology had no patients with delirium. Patients with delirium were 3 times more likely to die during their admission and were twice as likely to be discharged to institutional care (Table 1). 20 week mortality of patients with delirium was 26%.

Conclusion

Delirium is common in hospital inpatients. Delirium has a high morbidity and mortality. Better diagnosis of delirium in hospital may improve outcomes. Table 1: Mean(SD) unless stated. *p &lt; 0.05 Delirium (n = 65) No Delirium (n = 155) Male: % 46 46 Age* 81(11) 71(20) Clinical Frailty Score* 5.6(1.7) 3.8(1.8) Dementia (%)* 53 10 Assisted living: n(%) o Pre-admission * 18.5 3.2 o Post Admission * 44.6 22.6 Length of stay 33 (25) 30.6 (28) Mortality (%) o Hospital * 10.7 3.9 o 20 Weeks * 26.2 14.2 Readmission rate (%) 30.8 31.

A36 THE ROLE OF MICROBIAL INDOLE METABOLITES IN CONTROLLING INFLAMMATORY RESPONSES AND HEALING IN RESPONSE TO DSS-INDUCED COLITIS

Background

Failure to resolve inflammation is often associate with the complications of Crohn’s Disease (CD). The pregnane X receptor (PXR), a xenobiotic receptor, is recognized for its role in suppressing inflammation and has recently been shown to influence fibrogenesis in the liver. In the intestine, PXR-signaling can be influenced by the microbial tryptophan metabolite indole-3- propionic acid (IPA), which can modulate intestinal inflammation, in turn influencing fibrogenesis, resolution and healing. This suggests that the gut microbiota could modulate mucosal homeostasis and resolution of inflammation via microbial metabolites

Aims

To understand and characterize the interplay between microbial complexity and the regulation of host inflammatory and healing responses, specifically focusing on the PXR and its microbial metabolite ligand IPA.

Methods

Intestinal inflammation was induced using DSS (1%, 1.5%, 2% and 3.5%) for 5 days followed by healing for 25 days in C57Bl/6 stably derived moderately diverse mouse microbiota 2 (sDMDMm2) colonized gnotobiotic and C57Bl/6 specific pathogen free (SPF) mice. Inflammation, architectural changes and fibrosis were assessed using Haemotoxylin and Eosin and Masson-Trichrome histological stains. Weight was recorded daily for the first 10 days and every other day after for 25 days, for a total of 30 days. Fecal lipocalin was quantified in samples collected throughout the study to assess inflammation. Innate immune cell influx was measured by flow cytometry, and the microbiota assessed via 16S rRNA sequencing.

Results

The gnotobiotic sDMDMm2 mice were exquisitely sensitive to DSS-induced colitis, exhibiting significantly increased mortality and morbidity at 2% and 3.5% w/v DSS compared to the SPF group. To elicit the same degree of disease to assess recovery, sDMDMm2 mice were exposed to 1.5% DSS and SPF mice to 3.5% DSS. Following 25 days recovery, sDMDMm2 colonized mice showed increased levels of fecal lipocalin 2, as compared to the SPF mice. DSS-treated sDMDMm2 mice supplemented with IPA during their recovery presented lower levels of fecal lipocalin, similar to colitic SPF mice. IPA supplemented sDMDMm2 mice also exhibited greater overall survival, with no significant differences in neutrophil count compared to mice given H20 during recovery.

Conclusions

A model system with a less complex microbiota (sDMDMm2) has a higher susceptibility to acute inflammation and a diminished capacity to resolve said inflammation. Addition of the microbial metabolite IPA normalized the recovery of the sDMDMm2 colonized mice, to a response indistinguishable from SPF mice, while also increasing survival. These data highlight the importance of microbial complexity in the regulation of intestinal mucosal homeostasis.

Funding Agencies

CAG, CCC, CIHR

Urinary Ascites and Transient Intestinal Obstruction in a Preterm Infant: An Interesting Case of Posterior Urethral Valve

Posterior urethral valve (PUV) is the most common congenital cause of bladder outflow obstruction in male neonates. We report a preterm neonate with PUV who presented as nonimmune fetal hydrops with intestinal obstruction in the antenatal period. The mother of our patient is a 33-year-old woman who started her prenatal care at our hospital at 30 weeks' gestation. Her sonogram done at 32 weeks in our hospital revealed fetal hydrops. It showed polyhydramnios, mild pyelectasis of right kidney, normal left kidney, and fetal ascites. Amniocentesis revealed bile stained amniotic fluid. Ultrasound during the procedure showed dilated fetal bowel loops with increased echoes. Following delivery at 32 weeks postnatal exam showed ascites with absence of skin edema, pleural, or pericardial effusion. The abdominal sonogram showed distended urinary bladder and bilateral hydroureteronephrosis. Bladder catheterization was done which relieved the bladder outlet obstruction. Voiding cystourethrogram was done later which confirmed PUV and bilateral grade 5 vesicoureteral reflux. The formation of urinary ascites in PUV serves as a pop-off mechanism to relieve the intravesical and intrarenal pressure. When this happens by mechanisms other than bladder rupture, it can lead on to transient intestinal obstruction and hepatic synthetic defects.

Acceptance of Rules Generated by Machine Learning among Medical Experts

Objectives: The aim was to evaluate the potential for monotonicity constraints to bias machine learning systems to learn rules that were both accurate and meaningful.

Methods: Two data sets, taken from problems as diverse as screening for dementia and assessing the risk of mental retardation, were collected and a rule learning system, with and without monotonicity constraints, was run on each. The rules were shown to experts, who were asked how willing they would be to use such rules in practice. The accuracy of the rules was also evaluated.

Results: Rules learned with monotonicity constraints were at least as accurate as rules learned without such constraints. Experts were, on average, more willing to use the rules learned with the monotonicity constraints.

Conclusions: The analysis of medical databases has the potential of improving patient outcomes and/or lowering the cost of health care delivery. Various techniques, from statistics, pattern recognition, machine learning, and neural networks, have been proposed to “mine” this data by uncovering patterns that may be used to guide decision making. This study suggests cognitive factors make learned models coherent and, therefore, credible to experts. One factor that influences the acceptance of learned models is consistency with existing medical knowledge.

Brain Imaging in Cases with Positive Serology for Dengue with Neurologic Symptoms: A Clinicoradiologic Correlation

BACKGROUND AND PURPOSE

Dengue is a common arboviral disease, which uncommonly involves the brain. There has been a recent surge in dengue cases and dengue-related deaths in tropical countries. The aim of this study was to describe brain imaging findings in patients with dengue infection having neurologic symptoms.

MATERIALS AND METHODS

Thirty-five patients with positive serology for dengue with CNS symptoms undergoing imaging of the brain were included in the study. Clinical, laboratory, and imaging parameters were assessed and correlated to poor outcome.

RESULTS

A Glasgow Coma Scale score of ≤12 at presentation, clinical classification of severe-type dengue, and the presence of acute renal failure were associated with poor outcome. Imaging parameters associated with poor outcome were involvement of the thalami and cerebellar peduncles and the presence of diffusion restriction and hemorrhagic foci in the brain parenchyma.

CONCLUSIONS

Although not specific, dengue infection has imaging findings that can be used to narrow down the differential list and help in prognostication.

Abstract P6-02-02: Uridine diphosphate glucose dehydrogenase is required for hyaluronic acid production and breast cancer invasion

This abstract was withdrawn by the authors.

Frequency of rare BCR-ABL1 fusion transcripts in chronic myeloid leukemia patients

INTRODUCTION

The hallmark of chronic myeloid leukemia (CML) is the presence of Philadelphia chromosome, its resultant fusion transcript (BCR-ABL1), and fusion protein (p210). Alternate breakpoints in BCR (m-bcr, μ-bcr, and others) or ABL1 result in the expression of few rare fusion transcripts (e19a2, e1a2, e13a3, e14a3) and fusion proteins (p190, p200, p225) whose exact clinical significance remains to be determined.

METHODS

Our study was designed to determine the type and frequency of BCR-ABL1 fusion transcripts in 1260 CML patients and to analyze the prognosis and treatment response in patients harboring rare BCR-ABL1 fusion transcripts.

RESULTS

The frequency of various BCR-ABL1 fusion transcripts was as follows: e14a2 (60%), e13a2 (34.3%), e1a2 (1.2%), e1a2 + e13a2 (2.0%), e1a2 + e14a2 (1.8%), e19a2 (0.3%), and e14a3 (0.3%). CML patients with e1a2 transcripts had higher rates of disease progression, resistance, or suboptimal response to imatinib and failed to achieve major molecular response.

CONCLUSION

Characterization of the specific fusion transcript in CML patients is important owing to the difference in prognosis and response to therapy in addition to the conventional need for monitoring treatment response. CML patients with e1a2 transcripts have to be closely monitored due to the high incidence of disease progression and treatment resistance/failure.

Supplementation of ascorbic acid and α-tocopherol prevents arsenic-induced protein oxidation and DNA damage induced by arsenic in rats

Contamination of arsenic in drinking water is associated with several human diseases including cancer. It has been reported that oxidative stress plays a vital role in arsenic-induced biochemical and molecular alterations. The aim of the present study was to improve the understanding of arsenic-induced oxidative damage to proteins and to DNA and the role of antioxidants such as ascorbic acid and α-tocopherol in alleviating arsenic-induced damages in experimental rats. A significant increase in the levels of protein oxidation, DNA strand breaks, and DNA–protein cross-links was observed in blood, liver, and kidney of rats exposed to arsenic (100 ppm in drinking water) for 30 days. Co-administration of ascorbic acid and α-tocopherol to arsenic-exposed rats showed a substantial reduction in the levels of arsenic-induced oxidative products of protein and DNA. The results of this study support that free radical–mediated toxic manifestations of arsenic and also suggest that ascorbic acid and α-tocopherol supplementation can improve the arsenic-induced molecular alterations.

Pentoxifylline Plus Prednisolone versus Pentoxifylline Only for Severe Alcoholic Hepatitis: A Randomized Controlled Clinical Trial

Background:

Prednisolone and pentoxifylline (PTX) have been shown to be individually useful in severe alcoholic hepatitis with Maddrey discriminant function (MDF) score ≥32. Previous report suggests that PTX is probably superior to prednisolone alone. However the efficacy of PTX and prednisolone combination over PTX alone in the management of acute alcoholic hepatitis (MDF score ≥32) is yet unrevealed.

Aim:

The present study was initiated to find out the efficacy of combined pentoxifylline and prednisolone versus PTX alone in acute alcoholic hepatitis in respect of short and intermediate term outcomes.

Subjects and Methods:

A total of 124 patients with severe alcoholic hepatitis (MDF score ≥ 32) initially were evaluated. 62 patients who fulfilled the inclusion and exclusion criteria were randomized and divided into 2 groups. Group 1 received PTX only, whereas Group 2 received PTX plus Prednisolone. The total duration of follow-up was 12 months. Student's t-test, Chi-square test, the Kaplan-Meier methods were used for statistical analysis.

Results:

A total of 60 patients, 30 in each group were available for final analysis. In Group-1, 6 patients expired at the end of 1 year (5 within 3 months and another after 3 months). In Group 2, 10 patients expired at the end of 1 year (9 within 3 months and another after 3 months). Though survival probability is higher among Group 1 patients but the difference is not statistically significant.

Conclusion:

The combination of PTX plus Prednisolone yields no additional benefit in terms of mortality and morbidity from that of PTX monotherapy.

Effect of cell rupturing methods on the drying characteristics and lipid compositions of microalgae

This paper investigated the effect of cell rupturing methods on the drying characteristics and the lipid compositions of a green algae consortium grown in an open raceway pond. The ruptured microalgae samples obtained from French press, autoclave and sonication methods were used for conducting thin layer drying experiment at four drying temperatures (30, 50, 70 and 90 °C). The rate of moisture removal at each drying condition was recorded until no change in moisture loss. A typical drying curve for a microalgae consortium indicated that the rate of drying was limited by diffusion. Among three drying models (Newton, Page and Henderson-Pabis) used to fit the drying data, Page model fitted well on the experimental drying data with a coefficient of determination (R(2)) of 0.99. Solvent extraction of French press ruptured cells produced the highest total lipid yield with no significant change in lipid compositions.

Eribulin mesilate, a halichondrin B analogue, in the treatment of breast cancer

Eisai is developing eribulin mesilate (E-7389), a synthetic macrocyclic ketone analogue of the tubulin inhibitor halichondrin B, for the treatment of a variety of solid tumors that include but are not limited to breast and lung cancer. In this context, eribulin is in phase III clinical trials in breast cancer; however, it has also progressed to phase II for nonsmall cell lung cancer, soft tissue sarcomas, pancreatic, prostate, head and neck cancer, bladder and ovarian and related gynecological tumors. Eribulin has shown synergistic in vitro antiproliferative activity in combination with the breast cancer drugs gemcitabine, epirubicin, trastuzumab, docetaxel and vinorelbine. Clinical trials have established efficacy, safety and a distinct survival advantage of 2.5 months with eribulin as compared to other treatments of physician's choice in metastatic breast cancer patients with heavy pretreatment and taxane resistance. It has a manageable side effect profile, consisting mostly of neutropenia and fatigue, with distinct tolerance at full doses in renal dysfunction, a lower incidence of peripheral neuropathy, minimal chances of drug-drug interactions and hypersensitivity. It appears to be a suitable candidate for third-line monotherapy and beyond for locally advanced and metastatic breast cancer. This review will focus on published and peer-reviewed data on breast cancer.

Percutaneous external jugular vein catheterization in piglets using a triangulation technique

Chronic jugular vein or central venous cannulation is routinely performed in human and animal patients for access to blood circulation. In mature swine, chronic catheter placement techniques have typically involved venous isolation via extensive cut-down, blunt dissection and manipulation of ventral neck tissues prior to catheter placement. More recently, guide-wire-assisted percutaneous techniques have become standard practice in human and veterinary medicine due to the minimization of soft tissue and vessel damages. Laboratory animal piglets are becoming more popular research models because of their immature immunological system, ease of handling and costs. However, external jugular veins are very difficult to catheterize in paediatric animals including freshly weaned piglets. The objective of this study was to develop a simple, safe and efficient method for external jugular vein cannulation in young piglets. In total, 20 piglets were anaesthetized and percutaneously catheterized with a guide-wire technique using palpable anatomical landmarks and triangulation. With this minimally invasive catheterization, it has allowed our veterinarians and veterinary technicians to quickly and easily obtain central venous access in piglets undergoing operative procedures.

Dose escalation and pharmacodynamic study of intravenous adminstration of Reolysin, a live replication competent RNA virus in patients with advanced solid tumors

3583

Background: Reolysin is reovirus serotype 3 - Dearing strain, a double-stranded replication- competent RNA non-enveloped icosahedral virus. It induces cytopathic and anti-cancer effects in cells with an activating mutation in the ras proto-oncogene. Methods: This was a single center dose escalation trial of Reolysin administered intravenously every four weeks in doses ranging from 1X108 to 3X1010 tissue culture infective dose (TCID)50. Serum for neutralizing antibody, and serum, stool, saliva, and urine for viral shedding were collected. Tumor samples were analyzed for activating mutations in the ras and braf oncogenes. Results: Eighteen patients received 27 doses of Reolysin in 6 dose cohorts accomplishing a 300 fold dose escalation without a protocol-defined dose limiting toxicity. Drug related grade 2 toxicities included fatigue and fever (1 patient each). All patients developed neutralizing antibody during the course of the study. Viral shedding was observed in 6 patients [urine (5), serum (4), saliva (3), and stool (2)]. One patient with anthracycline and taxane refractory breast cancer experienced a partial response (PR) and her tumor had a mutation in the ras oncogene. Biopsy from a chest wall mass showed evidence of necrosis and viral replication by electron microscopy. The overall clinical benefit rate was 45% and appeared higher in patients with viral shedding (67%) than those without (33%). Conclusions: Reolysin administered as a one hour infusion on a monthly schedule is safe and well-tolerated even in multiple doses. Reolysin has anti-tumor activity as a single agent warranting further evaluation, including in combination with chemotherapy. Viral shedding may suggest intrapatient replication yielding a benefit and should be studied carefully in future studies.

[Table: see text]

Assessment of quality of life using FACT-G survey in a phase I trial in cancer patients

e20709

Background: Quality of life (QoL) assessment in clinical trials has been gaining more attention. FACT-G surveys have been validated to assess QoL in clinical trials involving oncology patient (Cella DF et al, J Clin Oncol 11:570–579, 1993). However, there is paucity of evaluation of QoL in patients with advanced cancer participating in Phase I clinical trials. Methods: FACT-G surveys were conducted within the context of a Phase I trial to identify a safe dose and potential drug-drug interations of capecitabine and irinotecan combination (Goel, S et al, Invest New Drugs 25:237–245, 2007). The FACT-G survey consists of 28 questions in 5 sections, namely, physical well-being, social/family well-being, emotional well-being, relationship with doctor, and functional well-being). Patients were requested to complete the FACT-G surveys at baseline and every two cycles thereafter (each cycle of 3 weeks duration). Results: Forty-one of 47 patients with advanced solid tumors who participated in the clinical trial completed FACT-G surveys. Mean scores were calculated for each time point. The mean QoL scores at baseline and post cycle 2 were 53 and 58, respectively (p = 0.1). Post cycle 4, the mean QoL score was 62 [p = 0.01, (vs. baseline)]. Following cycle 4, the number of respondents decreased to the extent where we were unable to ascertain any further changes in the QoL scores. Conclusions: It is feasible to use FACT-G survey as a tool to assess QoL in patients participating in an oncology phase I clinical trial. Although the sample size of the patient population was not powered for any statistical significance, there was a trend toward improving QoL based on FACT-G survey scores. This suggests that phase I clinical trials may provide improvement of QoL for some patients. FACT-G is a useful tool in assessing QoL in oncology phase I trial study population.

No significant financial relationships to disclose.

Novel neurosensory testing in cancer patients treated with the epothilone B analog, ixabepilone

BACKGROUND

We have previously established the recommended phase II dose (RPTD) of ixabepilone as 40 mg/m(2) administered over 1 h repeated every 3 weeks with neuropathy as a cumulative dose-limiting toxicity. We expanded the cohort at the RPTD to include detailed assessment of nerve damage in these patients. We report our findings on vibration perception threshold (VPT) and neuropathy.

PATIENTS AND METHODS

Forty-four patients were treated with a median (range) of three (1-14) cycles of ixabepilone. The VPT (5-min duration) and nerve conduction test (NCT, 10-min duration) were carried out in the office, before ixabepilone dosing, and every two cycles thereafter.

RESULTS

Neuropathy (grade 1 and grades 2-3) was observed in 17 (38.6%) and 11 (25%) patients, respectively. The mean increase in VPT as a function of grade 0-1 versus grades 2-3 neuropathy was 0.235 +/- 0.03 versus 0.869 +/- 0.09 (P = 0.049) vibration units. The F-wave frequency and distal motor latency, as assessed using the NCT, did not correlate with clinical neurotoxicity.

CONCLUSION

The change in VPT is observed early and likely reflects early vibration perception change. Mean change in VPT correlates with the severity of clinical neuropathy. Whether VPT change predicts onset of severe neuropathy warrants prospective testing and validation.