Peripheral neurotoxicity of oxaliplatin in combination with 5-fluorouracil (FOLFOX) or capecitabine (XELOX): a prospective evaluation of 150 colorectal cancer patients

Comparative efficacy of cetuximab combined with FOLFOX or CAPEOX in first-line treatment of RAS/BRAF wild-type metastatic colorectal cancer: a multicenter case-control study

FOLFOX combined with cetuximab is a recommended first-line treatment regimen for RAS/BRAF wild-type metastatic colorectal cancer (mCRC). CAPEOX combined with cetuximab differs from the FOLFOX regimen by using oral capecitabine instead of continuous infusion of fluorouracil, offering greater convenience and cost-effectiveness with higher patient acceptance. However, the comparative efficacy of these two regimens remains debatable, necessitating further evidence to explore any differences in their efficacy. This study collected medical records of mCRC patients who were treated with CAPEOX or FOLFOX combined with cetuximab from 1 October 2021 to 16 October 2023 at Harbin Medical University Cancer Hospital and the First Hospital of Shanxi Medical University. Eligible patients were selected based on inclusion criteria and followed up through the hospital's follow-up system and telephone interviews. Kaplan-Meier survival analysis and Cox proportional hazards regression analysis were used to assess patients' progression-free survival (PFS) and overall survival (OS). A total of 71 eligible patients were enrolled in this study; 43 patients received CAPEOX combined with cetuximab (Group A, n  = 43), and 28 patients received FOLFOX combined with cetuximab (Group B, n  = 28). The two groups achieved similar median PFS (mPFS) and median OS (mOS), with mPFS of 18 months and 12 months, respectively ( P  = 0.23), and mOS of 33 months and 20 months, respectively ( P  = 0.21), with no statistically significant differences. The results of this study demonstrated that CAPEOX combined with cetuximab is an equally viable option for first-line treatment of RAS/BRAF wild-type mCRC as FOLFOX combined with cetuximab.

Spinal pituitary adenylate cyclase-activating polypeptide and PAC1 receptor signaling system is involved in the oxaliplatin-induced acute cold allodynia in mice

Chemotherapy-induced peripheral neuropathy (CIPN) is a type of peripheral neuropathy that develops in patients treated with certain anticancer drugs. Oxaliplatin (OXA) causes CIPN in approximately 80-90 % of patients; thus, it is necessary to elucidate its underlying mechanism and develop effective treatments and prevention methods. The purpose of this study was to determine whether the pituitary adenylate cyclase-activating polypeptide (PACAP)/PAC1 receptor system in the spinal dorsal horn is involved in OXA-induced acute cold allodynia and examine the effect of a PAC1 receptor antagonist. Administration of OXA induced acute cold allodynia in wild-type mice, but not in PACAP-/- mice. In the dorsal root ganglia, OXA upregulated PACAP expression, particularly in small-sized neurons. OXA-induced cold allodynia was ameliorated by intrathecal (i.t.) injection of PACAP6-38 (peptide antagonist for PACAP receptor) and PA-8 (small-molecule antagonist specific for PAC1 receptor). I.t. PACAP, but not vasoactive intestinal polypeptide, resulted in cold allodynia, which was blocked by PA-8. OXA induced the activation of spinal astrocytes in a PAC1 receptor-dependent manner. The results suggest that spinal PACAP/PAC1 receptor systems are involved in OXA-induced acute cold allodynia through astrocyte activation. Furthermore, we demonstrated that the systemic administration of PA-8 resulted in therapeutic and preventative effects on OXA-induced acute cold allodynia. Because PA-8 did not affect the anticancer effects of OXA, we propose PAC1 receptor inhibition as a new strategy for the treatment and prevention of CIPN. PERSPECTIVE: Cold allodynia is a hallmark of OXA-induced peripheral neuropathy. This study demonstrated the involvement of spinal PACAP/PAC1 receptors in OXA-induced acute cold allodynia. We propose PAC1 receptor inhibition as a new strategy for the treatment and prevention of OXA-induced acute cold allodynia.

Repurposing chemotherapy-induced peripheral neuropathy grading

BACKGROUND AND PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) is perceived differently by patients and physicians, complicating its assessment. Current recommendations advocate combining clinical and patient-reported outcomes measures, but this approach can be challenging in patient care. This multicenter European study aims to bridge the gap between patients' perceptions and neurological impairments by aligning both perspectives to improve treatment decision-making.

METHODS

Data were pooled from two prospective studies of subjects (n = 372) with established CIPN. Patient and physician views regarding CIPN were assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE), Total Neuropathy Scale-clinical version (TNSc) items, and the disease-specific quality of life - Chemotherapy-Induced Peripheral Neuropathy questionnaire (QLQ-CIPN20) from the European Organization for Research and Treatment of Cancer (EORTC). To identify inherent neurotoxic severity patterns, we employed hierarchical cluster analysis optimized with k-means clustering and internally validated by discriminant functional analysis.

RESULTS

Both NCI-CTCAE and TNSc demonstrated a significant difference in the distribution of severity grades in relation to QLQ-CIPN20 scores. However, a proportion of subjects with different neurotoxic severity grades exhibited overlapping QLQ-CIPN20 scores. We identified three distinct clusters classifying subjects as having severely impaired, intermediately impaired, and mildly impaired CIPN based on TNSc and QLQ-CIPN20 scores. No differences in demographics, cancer type distribution, or class of drug received were observed.

CONCLUSIONS

Our results confirm the heterogeneity in CIPN perception between patients and physicians and identify three well-differentiated subgroups of patients delineated by degree of CIPN impairment based on scores derived from TNSc and QLQ-CIPN20. A more refined assessment of CIPN could potentially be achieved using the calculator tool derived from the cluster equations in this study. This tool, which facilitates individual patient classification, requires prospective validation.

Safety outcomes of rapid- versus standard-infusion rate oxaliplatin

PURPOSE

The National Comprehensive Cancer Network guidelines state that the oxaliplatin dose of 85 mg/m2 used in various gastrointestinal cancer regimens may be infused over a rapid rate of 85 min instead of the standard time of 120 min. We evaluated the safety outcomes of rapid administration of oxaliplatin compared to standard infusion.

METHODS

We performed a retrospective, cohort study by chart review. Adult patients who received oxaliplatin as part of a FOLFOX, FOLFOXIRI, or FOLRINOX chemotherapy regimen from January 1, 2018, through June 30, 2021, were included. Primary outcomes were the incidence of hypersensitivity reaction (HSR) and treatment modification of oxaliplatin due to adverse drug events. Secondary outcomes included peripheral neuropathy (PN), myelosuppressive signs, and oxaliplatin-related emergency department visit and/or hospital admission.

RESULTS

A total of 178 patients were included (90 and 88 in the rapid-rate and standard-rate groups, respectively). Rapid-rate oxaliplatin was not associated with increased HSR or difference in toxicity requiring dose reduction, delayed dose, or slowed infusion rate, but was associated with increased rate of permanent discontinuation of oxaliplatin, 7.8% and 1.1% in the rapid-rate group and standard-rate groups, respectively (p = 0.032). Peripheral neuropathy occurred in 72.2% and 42% of patients in the rapid-rate group and standard-rate groups, respectively (relative risk for PN, 2.09; 95%, CI: 1.43-3.04; p < .001). There were no differences in any other adverse drug event measured.

CONCLUSION

Rapid-rate oxaliplatin was associated with minimal treatment modifications; however, there was an increase in PN incidence. A faster rate of oxaliplatin administration may not be worth the increased risk of PN.

Motor disorders related to oxaliplatin-induced peripheral neuropathy: long-term severity and impact on quality of life

PURPOSE

Sensory chemotherapy-induced peripheral neuropathy (CIPN) is well-recognized, but motor CIPN remains understudied. This secondary analysis focused on the long-term severity and impact of motor disorders, their relation to sensory CIPN, neuropathic pain, psychological distress, and health-related quality of life (HRQoL) after oxaliplatin-based chemotherapy in colorectal cancer (CRC) survivors.

METHODS

Data from a multicenter, cross-sectional study were re-analyzed to explore motor CIPN among CRC survivors up to 5 years post-chemotherapy, with no longitudinal follow-up. Questionnaires assessed sensory and motor CIPN (QLQ-CIPN20), neuropathic pain (DN4), anxiety and depression (HADS), and HRQoL (QLQ-C30).

RESULTS

Among 405 CRC survivors, 31.1% had sensory CIPN as previously described. When categorizing the 405 CRC survivors based on the years since their last oxaliplatin-based chemotherapy, the motor scores derived from the QLQ-CIPN20 showed no significant difference between years (p = 0.08). Motor CIPN scores correlated with female gender, higher oxaliplatin dose intensity, sensory CIPN, and neuropathic pain. Motor CIPN also linked to decreased HRQoL and increased psychological distress.

CONCLUSION

The study underscores the detrimental impact of motor disorders on CRC survivors post-oxaliplatin-based chemotherapy. Oncologists should prioritize assessing and managing motor manifestations alongside sensory symptoms to enhance post-cancer quality of life.

TRIAL REGISTRATION

NCT02970526 (2016-11-22). https://classic.

CLINICALTRIALS

gov/ct2/show/NCT02970526?term=NCT02970526&draw=2&rank=1 .

Efficacy and safety of traditional plant-based medicines for preventing chronic oxaliplatin-induced peripheral neurotoxicity in patients with colorectal cancer: A systematic review and meta-analysis with core herb contribution

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional plant-based medicines (TMs) have been widely used to prevent chronic oxaliplatin-induced peripheral neurotoxicity (OIPN). However, the prevention and safety of TMs for chronic OIPN remain ambiguous. Furthermore, diverse TM prescriptions and complicated components limit in-depth research on the mechanisms of TMs.

AIM OF THIS STUDY

To determine core TMs and potential pharmacological pathways on the basis of a thorough investigation into the preventive benefits and safety of oral TMs for chronic OIPN in colorectal cancer (CRC).

METHODS

A search of the PubMed, Cochrane, Embase, CNKI, VIP, and Wanfang databases for RCTs reporting on TMs for chronic OIPN was conducted through December 1, 2022. Subgroup analysis, sensitivity analysis and meta-regression were applied to assess the impacts of influencing variables. The assessment of Risk of Bias was relied on Cochrane Risk of Bias tool. The funnel plot, Egger's test, and the Trim and Fill method were applied to identify potential publication bias. Trial sequential analyses (TSA) were carried out by the TSA tool to increase the robustness. The assessment of the quality of evidence was according to the GRADE system. System pharmacology analysis was employed to screen core herbal combinations to elucidate possible mechanisms for preventing chronic OIPN in CRC.

RESULTS

The pooled effect estimate with robustness increased by TSA analysis demonstrated that oral TMs appeared to significantly decrease the incidence of chronic OIPN (RR = 0.66, 95% CI (0.56, 0.78); P＜0.00001), leukocytopenia (RR = 0.65, 95% CI (0.54,0.79); P＜0.00001), and nausea and vomiting (RR = 0.72, 95% CI (0.61,0.84); P＜0.0001) as well as improve the Objective Response Rate (ORR) (RR = 1.31, 95% CI (1.09,1.56); P = 0.003). The incidence of severe chronic OIPN was revealed a significant reduction, particularly when chemotherapy was administered for periods of time shorter than six months (RR = 0.33, 95% CI (0.15,0.71); P = 0.005; actuation duration＜3 months; RR = 0.33, 95% CI (0.17,0.62); P = 0.0007; actuation duration≥3 months, ＜6 months). The considerable heterogeneity among studies may be attributable to the severity of dysfunction categorized by grade and accumulated dosage. Using core TMs consisting of Astragalus membranaceus (Fisch.) Bunge, Atractylodes Macrocephala Koidz., Poria cocos (Schw.) Wolf, and Codonopsis pilosula (Franch.) Nannf. To regulate nuclear factor-kappa B against inflammation caused by activation of microglia might be an approach to preventing chronic OIPN.

CONCLUSIONS

TMs appear to be effective and safe in the prevention of chronic OIPN, especially severe chronic OIPN. Additionally, core TMs consisting of Astragalus membranaceus (Fisch.) Bunge, Atractylodes Macrocephala Koidz., Poria cocos (Schw.) Wolf, and Codonopsis pilosula (Franch.) Nannf were presumably responsible for reducing the incidence of chronic OIPN, and the mechanism may be related to relieving inflammation. However, quality-assured trials with long-term follow-up for exploring inflammatory factors and preliminary research on core TMs and pharmacological pathways are needed.

Optimal duration of oxaliplatin-based adjuvant chemotherapy in patients with different risk factors for stage II-III colon cancer: a meta-analysis

BACKGROUND

The duration of oxaliplatin-based chemotherapy in high-risk stage II, low-risk stage III, and high-risk stage III colon cancer (CC) patients is controversial. To reduce the risk of adverse events (AEs) without compromising efficacy while improving chemotherapy compliance is crucial.

METHODS

The authors searched Cochrane, Embase, Pubmed, and Web of Science databases for articles from inception to August 8, 2023, the main outcomes were disease-free survival, overall survival, chemotherapy completion rates, and AE frequency.

RESULTS

Six randomized controlled trials (RCTs) involving 10 332 patients were included. Disease-free survival analysis revealed that only the high-risk stage III CC patients experienced better results with the 6-month FOLFOX regimen when compared with the 3-month regimen [Hazard ratio (HR): 1.32, 95% CI: 1.15-1.51, P <0.0001). Overall survival (OS) analysis revealed that extending the use of FOLFOX and CAPEOX regimens did not provide survival benefits for stage III CC patients (HR: 1.16, 95% CI: 0.9-1.49, and HR: 0.89, 95% CI: 0.67-1.18, P =0.40). The completion rate of the 3-month oxaliplatin-based adjuvant chemotherapy regimen was significantly higher than that of the 6-month regimen [Relative risk (RR): 1.16, 95% CI: 1.06-1.27, P =0.002]. Moreover, the 3-month regimen had significantly lower AE rates than the 6-month regimen (RR: 0.62, 95% CI: 0.57-0.68, P <0.00001), with differences mainly concentrated in grade 3/4 neutropenia (RR: 0.70, 95% CI: 0.59-0.85, P =0.0002), peripheral sensory neuropathy at ≥grade 2 (RR: 0.45, 95% CI: 0.38-0.53, P <0.00001), and hand-foot syndrome at ≥grade 2 (RR: 0.36, 95% CI: 0.17-0.77, P =0.009).

CONCLUSION

The 6-month FOLFOX regimen should only be recommended for high-risk stage III CC, while the 3-month regimen can be recommended for other stages. A 3-month CAPEOX regimen can be recommended for stage II-III CC.

Morphofunctional characterisation of axonal damage in different rat models of chemotherapy-induced peripheral neurotoxicity: The role of nerve excitability testing

BACKGROUND AND AIMS

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a common and long-lasting adverse event of several anticancer compounds, for which treatment has not yet been developed. To fill this gap, preclinical studies are warranted, exploiting highly translational outcome measure(s) to transfer data from bench to bedside. Nerve excitability testing (NET) enables to test in vivo axonal properties and can be used to monitor early changes leading to axonal damage.

METHODS

We tested NET use in two different CIPN rat models: oxaliplatin (OHP) and paclitaxel (PTX). Animals (female) were chronically treated with either PTX or OHP and compared to respective control animals. NET was performed as soon as the first injection was administered. At the end of the treatment, CIPN onset was verified via a multimodal and robust approach: nerve conduction studies, nerve morphometry, behavioural tests and intraepidermal nerve fibre density.

RESULTS

NET showed the typical pattern of axonal hyperexcitability in the 72 h following the first OHP administration, whereas it showed precocious signs of axonal damage in PTX animals. At the end of the month of treatment, OHP animals showed a pattern compatible with a mild axonal sensory polyneuropathy. Instead, PTX cohort was characterised by a rather severe sensory axonal polyneuropathy with minor signs of motor involvement.

INTERPRETATION

NET after the first administration demonstrated the ongoing OHP-related channelopathy, whereas in PTX cohort it showed precocious signs of axonal damage. Therefore, NET could be suggested as an early surrogate marker in clinical trials, to detect precocious changes leading to axonal damage.

Incidence and risk factors for developing chemotherapy-induced neuropathic pain in 500 cancer patients: A file-based observational study

OBJECTIVE

To define the incidence and risk factors for developing chemotherapy-induced neuropathic pain (CINP).

METHODS

Retrospective, file-based analysis on cancer patients who received any type of conventional chemotherapy and for whom neurological evaluation was asked to reveal the extent of chemotherapy-induced peripheral neurotoxicity (CIPN) with or without CINP. CINP was assessed by means of the PI-NRS and Douleur Neuropathique-4 questionnaire. The total neuropathy score-clinical version graded the severity of CIPN.

RESULTS

The medical files of 500 chemotherapy-treated cancer patients were reviewed. Any grade chronic CIPN was disclosed in 343 (68.6%) patients and CINP in 127 (37%) of them, corresponding to an overall percentage of 25.4% among all 500 included patients. The logistic regression analysis identified as independent predictors for CINP development the presence of uncomplicated diabetes (OR: 2.17; p = .039) and grade 2-3 chronic CIPN (OR: 1.61; p < .001) as also the administration of combined paclitaxel plus cisplatin (reference variable), compared to oxaliplatin (OR: 0.18; p = .001) and taxanes (OR: 0.16; p < .001). The increased severity of acute OXAIPN was associated with CINP (OR: 4.51; p < .001). OXA-treated patients with persistent CINP presented a worst likelihood to improve after chemotherapy discontinuation, than patients receiving combined paclitaxel plus cisplatin (OR: 50; p < .001).

CONCLUSION

The incidence of CINP in our cohort was comparable to previous reports, with severities fluctuating upwards during chemotherapy and declined post-chemotherapy. Uncomplicated diabetes, the combined paclitaxel plus cisplatin treatment and the increased severity of acute oxaliplatin neurotoxicity mostly increase the risk for developing CINP. OXA-treated patients present less possibilities to recover from CINP after chemotherapy discontinuation, than other chemotherapies.

Total neoadjuvant therapy in rectal cancer: the evidence and expectations

Current management of locally advanced rectal cancer achieves high cure rates, distant metastatic spread being the main cause of patients' death. Total neoadjuvant therapy (TNT) employs (chemo)radiotherapy and combined chemotherapy prior to surgery to improve the treatment outcomes. TNT has been shown to reduce significantly distant metastases, increase disease-free survival by 5 - 10% in 3 years, and finally also overall survival (≈ 5% in 7 years). It proved to double the rate of pathologic complete responses, making it an attractive strategy for non-operative management to avoid permanent colostomy in patients with distal tumors. In addition, it endorses adherence to the therapy due to better tolerance and, potentially, shortens its overall duration. A number of questions related to TNT remain currently unresolved including the indications, preferred radiotherapy and chemotherapy regimens, their sequence, timing of surgery, and role of adjuvant therapy. A stratified approach may be the optimal way to go.

Experiences and Perceptions of Patients with Oxaliplatin-Induced Cold Sensitivity in Turkey: A Qualitative Study

OBJECTIVES

This study aimed to explore and describe the impact on patients with oxaliplatin-induced cold sensitivity in the early stages.

DATA SOURCES

An inductive design was used for this qualitative study, which included open-ended, and in-depth interviews with 18 cancer patients. Throughout the study, the authors followed the COREQ checklist. The interviews were audiorecorded and listened to multiple times. Observation notes were also recorded following each interview. Thematic analysis developed six main themes and 13 subthemes. The first theme concerns changing habits, including changes in fluid intake and clothing choice, changes in bathing and eating habits, and changes in caregiver roles. The second theme includes changes in daily routine behaviors that are perceived as difficulties with changing routines. The third theme is avoiding triggers; the fourth theme is anxiety about self-care. The fifth theme includes a subtheme of difficulty in contact. The final theme includes adaptation to life, caring responsibilities, changes in sexual functions, the performance of religious activities, and social activities IMPLICATIONS FOR NURSING PRACTICE: This study provides an overview of the lived experiences of oxaliplatin-induced cold sensitivity among cancer patients. Patients faced fewer adverse events by avoiding initiators from the first treatment. They changed their eating and drinking habits owing to difficulties. The findings of this study can be used to better understand oxaliplatin-induced cold sensitivity, identify patients needs based on their experience, and develop interventions to improve patient outcomes.

Incidence and risk factors associated with development of oxalipatin-induced acute peripheral neuropathy in colorectal cancer patients

INTRODUCTION

Oxaliplatin utilized in colorectal neoplasms treatment could induce acute peripheral neuropathy (APN) which is a dreadful and frequent adverse event. The objective of this study is to estimate incidence of APN induced by oxaliplatin cumulative incidence in cancer patients colorectal and to describe the distribution of the APN incidence according to demographic and clinical characteristics, as well as according to oxaliplatin cumulative dose.

MATERIAL AND METHODS

This is a prospective descriptive study which took place from June to December 2018 at the Salah Azaiz Institute, Tunis. Demographic data, clinical data and data on oxaliplatin administration were collected from patient interview, medical files and pharmaceutical databases.

RESULTS

The APN (grade 1, grade 2 and grade 3) cumulative incidence during the period of six months of follow up was 86% (95% CI [0.7815-0.9132]). While 38.3% (95% CI [0.29-0.48]) of the patients had grade 2 or 3 neuropathy. The search for factors associated with the risk of grade 2 and 3 NAP revealed trend significant association with diabetes (adjusted RR = 5.7 (IC95% [0.9- 37.3]; p = 0.07). Moreover, there was significant association with oxaliplatin cumulative dose (≥421 mg/m2) to increase the risk of APN grade 2 and 3 (adjusted RR = 7.8; [2.7-22.7]; p = 0.0001). Furthermore, significant association with obesity to increase the risk of APN grade 2 and 3 (adjusted RR = 5.3 [1.1- 25.4]; p = 0.04) was found. Among the patients included, 31.1% experienced oxaliplatin dose reduction and in the majority of cases this reduction is due to neurotoxicity (90.9%).

CONCLUSION

The high incidence of oxaliplatin-induced APN remains an embarrassing and handicapping side effect. Our study has shown that oxaliplatin cumulative dose (≥421 mg/m2), diabetes and obesity are risk factor for the development of grade 2 and 3 APN.

Neurological Complications of Conventional and Novel Anticancer Treatments

Various neurological complications, affecting both the central and peripheral nervous system, can frequently be experienced by cancer survivors after exposure to conventional chemotherapy, but also to modern immunotherapy. In this review, we provide an overview of the most well-known adverse events related to chemotherapy, with a focus on chemotherapy induced peripheral neurotoxicity, but we also address some emerging novel clinical entities related to cancer treatment, including chemotherapy-related cognitive impairment and immune-mediated adverse events. Unfortunately, efficacious curative or preventive treatment for all these neurological complications is still lacking. We provide a description of the possible mechanisms involved to drive future drug discovery in this field, both for symptomatic treatment and neuroprotection.

Efficacy of neoadjuvant CapeOX/mFOLFOX6 without radiation for patients with baseline resectable mid-low locally advanced rectal cancer

OBJECTIVES

Chemotherapy without radiation therapy for locally advanced rectal cancer (LARC) has attracted increasing attention, but the optimal schema remains controversial. In this study, we aimed to assess the efficacy and toxicity of neoadjuvant chemotherapy (nCT) of two regimens for patients with mid-low baseline resectable LARC.

METHODS

A retrospective study was performed in 131 patients with baseline resectable LARC in a single center between April 2016 and August 2020. All patients received four cycles of neoadjuvant CapeOX or mFOLFOX6 before surgery. Clinical characteristics, pathological response, and survival status were then assessed.

RESULTS

After a 1:1 propensity score matching, 96 patients were enrolled, including 48 receiving CapeOX and 48 receiving mFOLFOX6. The objective regression rates were 50.00% and 58.33%, and the pathological complete response rates were 6.25% and 8.33%, respectively, in the CapeOX and mFOLFOX6 groups. Patients who received mFOLFOX6 had a better tumor regression grade (TRG) than those who received CapeOX (P = 0.005). Patients in both groups had similar survival outcomes.

CONCLUSIONS

The nCT has shown promising tumor response and survival outcomes, which can be a treatment option for baseline resectable LARC. For the two regimens, mFOLFOX6 provided better TRG than CapeOX, although no differences were observed in disease-free survival and OS.

Sodium-Calcium Exchanger 2: A Pivotal Role in Oxaliplatin Induced Peripheral Neurotoxicity and Axonal Damage?

Oxaliplatin (OHP)-induced peripheral neurotoxicity (OIPN) is a frequent adverse event of colorectal cancer treatment. OIPN encompasses a chronic and an acute syndrome. The latter consists of transient axonal hyperexcitability, due to unbalance in Na+ voltage-operated channels (Na+VOC). This leads to sustained depolarisation which can activate the reverse mode of the Na+/Ca2+ exchanger 2 (NCX2), resulting in toxic Ca2+ accumulation and axonal damage (ADa). We explored the role of NCX2 in in vitro and in vivo settings. Embryonic rat Dorsal Root Ganglia (DRG) organotypic cultures treated with SEA0400 (SEA), a NCX inhibitor, were used to assess neuroprotection in a proof-of-concept and pilot study to exploit NCX modulation to prevent ADa. In vivo, OHP treated mice (7 mg/Kg, i.v., once a week for 8 weeks) were compared with a vehicle-treated group (n = 12 each). Neurophysiological and behavioural testing were performed to characterise acute and chronic OIPN, and morphological analyses were performed to detect ADa. Immunohistochemistry, immunofluorescence, and western blotting (WB) analyses were also performed to demonstrate changes in NCX2 immunoreactivity and protein expression. In vitro, NCX inhibition was matched by ADa mitigation. In the in vivo part, after verifyingboth acute and chronic OIPN had ensued, we confirmed via immunohistochemistry, immunofluorescence, and WB that a significant NCX2 alteration had ensued in the OHP group. Our data suggest NCX2 involvement in ADa development, paving the way to a new line of research to prevent OIPN.

Multicenter phase II clinical study of the efficiency and safety of capecitabine plus intermittent oxaliplatin with bevacizumab as first-line therapy in patients with metastatic colorectal cancer (VOICE trial)

PURPOSE

The aim of this phase II study was to evaluate the efficacy and safety of combination therapy with five-cycle CAPOX (capecitabine plus oxaliplatin) plus bevacizumab, followed by five-cycle maintenance therapy with capecitabine plus bevacizumab and reintroduction of CAPOX plus bevacizumab for five cycles, with a preplanned intermittent oxaliplatin strategy in metastatic colorectal cancer (mCRC).

METHODS

Patients with untreated mCRC were administered CAPOX (130 mg/m² oxaliplatin on day 1, 2000 mg/m²/day capecitabine on days 1-14, every 21 days) + bevacizumab (7.5 mg/kg) every 3 weeks for five cycles, maintenance treatment without oxaliplatin for five cycles, and CAPOX + bevacizumab reintroduction for five cycles or upon tumor progression. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were the time to treatment failure (TTF), overall survival, response rate (RR), and safety.

RESULTS

Forty-seven patients who fulfilled the inclusion criteria were enrolled in the evaluation of efficacy and safety. Median PFS was 14.1 months (95% confidence interval [CI], 8.6-19.5), and median TTF was 12.3 months (95% CI, 10.3-14.3). The objective RRs were 51.1% (24/47) during induction therapy, 58.3% (21/36) during maintenance therapy, and 63.6% (14/22) during reintroduction therapy. The frequency of patients with neutropenia, diarrhea, peripheral sensory neuropathy, venous thromboembolism, or grade ≥ 3 allergic reactions was 2.1%.

CONCLUSION

CAPOX plus bevacizumab therapy with a preplanned intermittent oxaliplatin strategy consisting of brief five-cycle induction therapy, five-cycle maintenance therapy with capecitabine plus bevacizumab, and five-cycle reintroduction therapy consisting of CAPOX plus bevacizumab is safe and effective for mCRC patients.

TRIAL REGISTRATION

UMIN ID: 000,005,732, date of registration: June 7, 2011.  https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000006695.

Treatment strategy of oxaliplatin-induced peripheral neuropathy: a retrospective, nationwide study

PURPOSE

Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse event of cancer treatment; however, no drug is recommended for the prevention of CIPN. In Japan, several drugs such as Gosha-Jinki-Gan and duloxetine are frequently administered as a treatment for CIPN. The aim of this study was to elucidate prescription patterns of drugs administered for CIPN caused by oxaliplatin and the association between these drugs and the duration of oxaliplatin treatment.

METHODS

We conducted a retrospective nationwide study using the JMDC administrative claims database (January 2005-June 2020; JMDC Inc., Japan). Patients newly treated with oxaliplatin were identified, and prescription patterns of CIPN medication including Gosha-Jinki-Gan, pregabalin, duloxetine, mecobalamin, and mirogabalin were investigated. The primary outcome was the duration of oxaliplatin treatment. Multivariable logistic regression analysis was performed to examine the association between CIPN medication and duration of oxaliplatin treatment.

RESULTS

A total of 4,739 patients who newly received oxaliplatin were identified. Of these, 759 (16.0%) had received CIPN medication. Duloxetine was administered in 99 (2.1%) patients. Multivariable logistic regression analysis revealed that CIPN medication was significantly associated with the prolonged duration of oxaliplatin treatment (odds ratio: 2.35, [95% confidence interval: 1.99-2.77]).

CONCLUSION

Real-world data demonstrated that the administration rate of CIPN medication was higher in patients who received oxaliplatin treatment for over 6 months.

Predictive Biomarkers of Oxaliplatin-Induced Peripheral Neurotoxicity

Oxaliplatin (OXA) is a platinum compound primarily used in the treatment of gastrointestinal cancer. OXA-induced peripheral neurotoxicity (OXAIPN) is the major non-hematological dose-limiting toxicity of OXA-based chemotherapy and includes acute transient neurotoxic effects that appear soon after OXA infusion, and chronic non-length dependent sensory neuronopathy symmetrically affecting both upper and lower limbs in a stocking-and-glove distribution. No effective strategy has been established to reverse or treat OXAIPN. Thus, it is necessary to early predict the occurrence of OXAIPN during treatment and possibly modify the OXA-based regimen in patients at high risk as an early diagnosis and intervention may slow down neuropathy progression. However, identifying which patients are more likely to develop OXAIPN is clinically challenging. Several objective and measurable early biomarkers for OXAIPN prediction have been described in recent years, becoming useful for informing clinical decisions about treatment. The purpose of this review is to critically review data on currently available or promising predictors of OXAIPN. Neurological monitoring, according to predictive factors for increased risk of OXAIPN, would allow clinicians to personalize treatment, by monitoring at-risk patients more closely and guide clinicians towards better counseling of patients about neurotoxicity effects of OXA.

Older adults with colon cancer are not different from younger ones, but treated differently: Retrospective analysis from single centre

AIM

Decision- making of the treatment of colon cancer for the older patients becomes more complicated in consequence of comorbidities and geriatric syndromes, most importantly frailty. In the present study, we aimed to investigate whether there is a difference between tumour characteristics, treatment choices, and outcomes between the younger and older adults.

METHOD

The patients who were diagnosed with colorectal carcinoma in our centre between 2010 and 2015 included. Clinicopathological features of tumour, treatment choices and survivals of the patients were recorded. Patients were separated into two groups according to their chronological age.

RESULTS

The present study included 465 patients, there were 173 patients aged 65 years and older. Clinicopathological features were similar in both groups. Adjuvant chemotherapy was given in similar rates. Whereas combination chemotherapies were preferred in younger patients as first-line therapy, single agents were given to the older group(p-value < 0.001). No significant differences were observed between combination therapy and monotherapy as progression-free and overall survival in older adults(p value > 0.05). It was observed that 53.2% of the older patients was not treated with any biological treatment (p-value < 0.001).

DISCUSSION

Geriatric people are underrepresented in clinical trials,because of the presence of the limitations in the older patients. The results of our study revealed older patients with colon cancer patients underwent surgery less than the younger ones, they recieved monotherapy more frequently as first-line chemotherapy, and less frequently targeted therapy. Their mortality was higher. It was shown that decision-making of colon cancer therapy is influenced by age according to our results.

Oxaliplatin-induced neuropathy occurs through impairment of haemoglobin proton buffering and is reversed by carbonic anhydrase inhibitors

Oxaliplatin is a cornerstone chemotherapeutic used in the treatment of colorectal cancer, the third leading cause of death in Western countries. Most side effects of this platinum-containing drug are adequately managed in the clinic, although acute and long-term neurotoxicity still severely compromises the quality of life of patients treated with oxaliplatin. We have previously demonstrated that therapeutically relevant concentrations/doses of oxaliplatin lead to a reduction in intracellular pH in mouse dorsal root ganglion (DRG) neurons in vitro and in vivo and that this alteration sensitizes TRPA1 and TRPV1 channels, which most likely mediate the allodynia associated with treatment. In this study, we show that oxaliplatin leads to a reduction of intracellular pH by forming adducts with neuronal haemoglobin, which acts in this setting as a proton buffer. Furthermore, we show that FDA-approved drugs that inhibit carbonic anhydrase (an enzyme that is linked to haemoglobin in intracellular pH homeostasis), ie, topiramate and acetazolamide, revert (1) oxaliplatin-induced cytosolic acidification and TRPA1 and TRPV1 modulation in DRG neurons in culture, (2) oxaliplatin-induced cytosolic acidification of DRG of treated animals, and (3) oxaliplatin-induced acute cold allodynia in mice while not affecting OHP-induced cytotoxicity on cancer cells. Our data would therefore suggest that reversal of oxaliplatin-induced cytosolic acidification is a viable strategy to minimize acute oxaliplatin-induced symptoms.

Addressing the Need of a Translational Approach in Peripheral Neuropathy Research: Morphology Meets Function

Peripheral neuropathies (PNs) are a type of common disease that hampers the quality of life of affected people. Treatment, in most cases, is just symptomatic and often ineffective. To improve drug discovery in this field, preclinical evidence is warranted. In vivo rodent models allow a multiparametric approach to test new therapeutic strategies, since they can allow pathogenetic and morphological studies different from the clinical setting. However, human readouts are warranted to promptly translate data from the bench to the bedside. A feasible solution would be neurophysiology, performed similarly at both sides. We describe a simple protocol that reproduces the standard clinical protocol of a neurophysiology hospital department. We devised the optimal montage for sensory and motor recordings (neurography) in mice, and we also implemented F wave testing and a short electromyography (EMG) protocol at rest. We challenged this algorithm by comparing control animals (BALB/c mice) with a model of mild neuropathy to grasp even subtle changes. The neurophysiological results were confirmed with neuropathology. The treatment group showed all expected alterations. Moreover, the neurophysiology matched the neuropathological analyses. Therefore, our protocol can be suggested to promptly translate data from the bench to the bedside and vice versa.

Efficacy and Long-term Peripheral Sensory Neuropathy of 3 vs 6 Months of Oxaliplatin-Based Adjuvant Chemotherapy for Colon Cancer: The ACHIEVE Phase 3 Randomized Clinical Trial

Question

Can a shortened course of adjuvant oxaliplatin-based chemotherapy reduce peripheral sensory neuropathy (PSN) without compromising efficacy in patients with stage III colon cancer?

Findings

In this phase 3 randomized clinical trial of 1313 patients, 3 months of adjuvant therapy significantly reduced the rate of any grade of PSN at 3 years, compared with 6 months of treatment. The incidence of any grade of PSN lasting for 3 years was significantly lower for the chemotherapy drug capecitabine plus oxaliplatin (CAPOX) than for the drug modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6); these treatment outcomes were consistent with those of the International Duration Evaluation of Adjuvant Chemotherapy (IDEA) Collaboration.

Meaning

A 3-month chemotherapy regimen of CAPOX may be the most appropriate treatment option for colon cancer, particularly in low-risk patients.

Importance

Oxaliplatin-based chemotherapy is associated with debilitating peripheral sensory neuropathy (PSN) for patients with stage III colon cancer.

Objective

To assess disease-free survival (DFS) and long-lasting PSN in patients treated with 3 vs 6 months of adjuvant oxaliplatin-based chemotherapy.

Design, Setting, and Participants

An open-label, multicenter, phase 3 randomized clinical trial of 1313 Asian patients with stage III colon cancer was conducted investigating the noninferiority of 3 vs 6 months of adjuvant oxaliplatin-based chemotherapy. From August 1, 2012, to June 30, 2014, participants were randomized to the 2 treatment groups. Data were analyzed from July 2017 to June 2018.

Interventions

Patients were randomized to receive 3 or 6 months of adjuvant chemotherapy. The choice of chemotherapy regimen, with the drugs modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) or capecitabine plus oxaliplatin (CAPOX), was at the discretion of the treating physician.

Main Outcomes and Measures

The primary outcome was DFS. Secondary end points included the evaluation of PSN for up to 3 years and overall survival.

Results

Of the 1313 patients (651 were women and mean age was 66 [range, 28-85] years) enrolled and randomized, 22 were not treated because 10 were unable to begin treatment within 2 weeks of enrollment, 7 withdrew their consent, and 5 were not treated for various other reasons. Of 1291 patients treated (650 in the 3-month arm and 641 in the 6-month arm), 969 (75%) received the chemotherapy drug CAPOX. The hazard ratio (HR) for DFS of the 3-month arm compared with the 6-month arm was 0.95 (95% CI, 0.76-1.20). Hazard ratios were 1.07 (95% CI, 0.71-1.60) and 0.90 (95% CI, 0.68-1.20) for the drugs mFOLFOX6 and CAPOX, and 0.81 (95% CI, 0.53-1.24) and 1.07 (95% CI, 0.81-1.40) for patients with low-risk disease (TNM classification stages T1-3 and N1) and high-risk disease (stages T4 or N2), respectively. The rates of any grade of PSN lasting for 3 years in the 3-month vs 6-month treatment arms were 9.7% vs 24.3% (P < .001). Incidence of PSN lasting for 3 years was significantly lower for patients treated with CAPOX than for patients treated with mFOLFOX6 in both the 3-month (7.9% vs 15.7%; P = .04) and 6-month arms (21.0% vs 34.1%; P = .02).

Conclusions and Relevance

The incidence of long-lasting PSN was significantly lower for 3 months than for 6 months of therapy, and significantly lower for treatment with the drug CAPOX than with mFOLFOX6. Since the shortened therapy duration did not compromise outcomes, a 3-month course of CAPOX may be the most appropriate treatment option, particularly for patients with low-risk disease.

Trial Registration

UMIN Clinical Trials Registry: UMIN000008543

Oxaliplatin rechallenge in metastatic colorectal cancer patients with clinically significant oxaliplatin-induced peripheral neurotoxicity

We investigated whether rechallenge with oxaliplatin (OXA) can worsen the pre-existing oxaliplatin-induced peripheral neurotoxicity (OXAIPN) in metastatic colorectal cancer (mCRC) patients. Patients previously treated with OXA, having clinically significant grade 1 or 2 OXAIPN were assessed, after receiving rechallenge with OXA, using the clinical version of the Total Neuropathy Score (TNSc). Peripheral neuropathy was assessed at the end of first OXA exposure and at completion of OXA rechallenge. The first line OXA-based chemotherapy was completed at least 9 months earlier (OXA-free interval). We studied 25 mCRC patients, 14 males and 11 females, with a median age of 63 (35-77) years. After their first exposure to OXA-based chemotherapy, 9 (36%) patients developed grade 1 OXAIPN and 16 patients grade 2 (64%) neurotoxicity. OXA reintroduction with a median of 10 (8-14) cycles led to grade 1 OXAIPN in two patients (8%), grade 2 in 19 patients (76%), and grade 3 neuropathy in 4 (16%) patients Worsening of pre-existing OXAIPN was documented in seven (28%) patients and was significantly associated with higher OXA delivered cumulative dose (P < .001). Median TNSc scores following treatment (10; range 4-18) were significantly increased (P < .001), when compared to the scores recorded at the end of first line treatment (8; range 2-12). Rechallenging OXA appears to relatively worsen the severity of existing OXAIPN. However, the majority of rechallenged patients developed a clinically significant (grade 2) OXAIPN, rather than treatment-emergent grade 3. As such, OXA rechallenge might be a feasible option in patients previously having OXAIPN.

Symptom Experiences in Colorectal Cancer Survivors After Cancer Treatments: A Systematic Review and Meta-analysis

BACKGROUND

With improved survivorship rates for colorectal cancer (CRC), more CRC survivors are living with long-term disease and treatment side effects. Little research exists on CRC symptoms or symptom management guidelines to support these individuals after cancer treatments.

OBJECTIVES

The aims of this study were to systematically review symptom experiences, risk factors, and the impact of symptoms and to examine the pooled frequency and severity of symptoms via meta-analyses in CRC survivors after cancer treatments.

METHODS

Relevant studies were systematically searched in 7 databases from 2009 to 2019. Meta-analysis was conducted for pooled estimates of symptom frequency and severity.

RESULTS

Thirty-five studies met the inclusion criteria. Six studies assessed multiple CRC symptoms, whereas 29 focused on a single symptom, including peripheral neuropathy, psychological distress, fatigue, body image distress, cognitive impairment, and insomnia. The pooled mean frequency was highest for body image distress (78.5%). On a scale of 0 to 100, the pooled mean severity was highest for fatigue (50.1). Gastrointestinal and psychological symptoms, peripheral neuropathy, and insomnia were also major problems in CRC survivors. Multiple factors contributed to adverse symptoms, such as younger age, female gender, and lack of family/social support. Symptoms negatively impacted quality of life, social and sexual functioning, financial status, and caregivers' physical and mental conditions.

CONCLUSIONS

Colorectal cancer survivors experienced multiple adverse symptoms related to distinct risk factors. These symptoms negatively impacted patients and caregivers' well-being.

IMPLICATIONS FOR PRACTICE

Healthcare providers can use study findings to better assess and monitor patient symptoms after cancer treatments. More research is needed on CRC-specific symptoms and their effective management.

Ibudilast for prevention of oxaliplatin-induced acute neurotoxicity: a pilot study assessing preliminary efficacy, tolerability and pharmacokinetic interactions in patients with metastatic gastrointestinal cancer

PURPOSE

This prospective, open-label, sequential 'before vs. after' pilot study was conducted to provide preliminary efficacy and tolerability data for ibudilast in the prevention of oxaliplatin-induced neurotoxicity in patients with metastatic upper gastrointestinal or colorectal cancer. Any potential impact of ibudilast on oxaliplatin and 5-fluorouracil pharmacokinetics was also explored.

METHODS

Participants were administered a chemotherapy cycle (FOLFOX or CapeOx), followed by a chemotherapy cycle with co-administration of ibudilast 30 mg b.i.d. p.o. Efficacy was assessed on Day 3 and end of cycle using the Oxaliplatin-Specific Neurotoxicity Scale (OSNS) and additional clinical/patient-reported neurotoxicity measures. A population pharmacokinetic approach was used to determine oxaliplatin and 5-fluorouracil pharmacokinetics with and without ibudilast.

RESULTS

Sixteen participants consented; 14 completed both chemotherapy cycles. Across all measures, the majority of participants experienced either an improvement or no worsening of neurotoxicity with ibudilast treatment. Based on OSNS assessments, acute neurotoxicity was unchanged in 12/14 participants and improved in 2/14 participants. The 90% confidence interval (CI) of the dose-normalised ratio of oxaliplatin AUC (90% CI 95.0-109%) and 5-fluorouracil AUC (90% CI 66.5-173%) indicated no significant impact of ibudilast on systemic exposure.

CONCLUSION

This pilot study indicated ibudilast co-administration may improve or stabilise oxaliplatin-induced neurotoxicity. Given the expected worsening of symptoms in patients with continued chemotherapy, this represents a signal of effect that warrants further investigation. Pharmacokinetic analysis indicates ibudilast has no significant effect on oxaliplatin pharmacokinetics, and is unlikely to influence pharmacokinetics of 5-fluorouracil.

CLINICAL TRIAL REGISTRATION

Trial registration number: UTN U1111-1209-0075 and ANZCTRN12618000232235 (registered 13/02/2018).

The Incidence of Oxaliplatin-Induced Peripheral Neurotoxicity at Khartoum Oncology Hospital: A Cross-Sectional Survey

Objective:

Using oxaliplatin-based chemotherapy in the treatment of cancer patients can cause a unique form of acute and chronic peripheral neurotoxicities. This study mainly aims to assess the incidence of oxaliplatin-induced peripheral neuropathy (OXAIPN).

Methods:

A cross-sectional study among 121 patients treated with oxaliplatin-based chemotherapy was conducted during the period of January to April 2019 at Khartoum Oncology Hospital. The incidence of acute neurotoxicity was assessed using a descriptive questionnaire for most common hyperexcitability and transient symptoms, while the incidence of chronic neurotoxicity was measured by the 20-item European Organization for Research and Treatment of Cancer Quality of Life Questionnaire for patients with chemotherapy-induced peripheral neuropathy and graded by the National Cancer Institute's Common Terminology Criteria for Adverse Events, Version 4.03.

Results:

Acute and chronic OXAIPN were found in 49.6% and 41.3% of patients, respectively. Most of the patients who developed acute OXAIPN symptoms manifested cold-induced pharyngolaryngeal dysesthesias (73.3%) or perioral paresthesias (71.7%). No significant association exists between the severity of chronic neurotoxicity and basic demographics. Most (79.1%) of the patients did not inform the doctors about their complaints, and 43.5% of those who informed doctors did not take any medication to manage OXAIPN.

Conclusions:

This study exhibits that oxaliplatin-based chemotherapy can cause symptoms of peripheral neurotoxicity in most of the patients with colorectal or gastric cancer in the form of acute neurotoxicity or chronic neurotoxicity.

Management of Oxaliplatin-Induced Peripheral Sensory Neuropathy

Oxaliplatin-induced peripheral neurotoxicity (OIPN) is a severe and potentially permanent side effect of cancer treatment affecting the majority of oxaliplatin-treated patients, mostly with the onset of acute symptoms, but also with the establishment of a chronic sensory loss that is supposed to be due to dorsal root ganglia neuron damage. The pathogenesis of acute as well as chronic OIPN is still not completely known, and this is a limitation in the identification of effective strategies to prevent or limit their occurrence. Despite intense investigation at the preclinical and clinical levels, no treatment can be suggested for the prevention of OIPN, and only limited evidence for the efficacy of duloxetine in the treatment setting has been provided. In this review, ongoing neuroprotection clinical trials in oxaliplatin-treated patients will be analyzed with particular attention paid to the hypothesis leading to the study, to the trial strengths and weaknesses, and to the outcome measures proposed to test the efficacy of the therapeutic approach. It can be concluded that (1) prevention and treatment of OIPN still remains an important and unmet clinical need, (2) further, high-quality research is mandatory in order to achieve reliable and effective results, and (3) dose and schedule modification of OHP-based chemotherapy is currently the most effective approach to limit the severity of OIPN.

Serum neurofilament light chain levels as a biomarker of neuroaxonal injury and severity of oxaliplatin-induced peripheral neuropathy

We set out to determine the usability of serum neurofilament light chain (sNfL), serum glial fibrillary acidic protein (sGFAP), and retinal parameters by using optical coherence tomography (OCT) as reliable biomarkers of the progression of oxaliplatin-induced peripheral neuropathy (OIPN). Forty-three patients scheduled to undergo oxaliplatin-based chemotherapy at the National Cancer Center of Korea between June 2018 and October 2019 were prospectively assessed at baseline, 3 months, and 6 months of chemotherapy. Patients were assessed on clinical scales and underwent OCT, sNfL, and sGFAP level measurement at each follow-up visit. By applying the National Cancer Institute-Common Toxicity Criteria (NCI-CTC), OIPN was classified as grade 1 in 12 (28%) patients, grade 2 in 25 (58%), and grade 3 in 5 (12%) at 6 months of chemotherapy. sNfL levels increased during oxaliplatin administration, while serial sGFAP levels or retinal parameters did not change. Patients with grade-3 OIPN showed significantly higher mean sNfL levels than patients with grade 0-2 OIPN at 6 months of treatment. At 4-6 months after completion of chemotherapy, sNfL levels were significantly reduced compared to the levels at 6 months of chemotherapy. Monitoring of sNfL during chemotherapy can indicate ongoing neuroaxonal injury and the severity of OIPN.

Platinum-induced peripheral neurotoxicity: From pathogenesis to treatment

Platinum-induced peripheral neurotoxicity (PIPN) is a common side effect of platinum-based chemotherapy that may cause dose reduction and discontinuation, with oxaliplatin being more neurotoxic. PIPN includes acute neurotoxicity restricted to oxaliplatin, and chronic non-length-dependent sensory neuronopathy with positive and negative sensory symptoms and neuropathic pain in both upper and lower limbs. Chronic sensory axonal neuropathy manifesting as stocking-and-glove distribution is also frequent. Worsening of neuropathic symptoms after completing the last chemotherapy course may occur. Motor and autonomic involvement is uncommon. Ototoxicity is frequent in children and more commonly to cisplatin. Platinum-based compounds result in more prolonged neuropathic symptoms in comparison to other chemotherapy agents. Patient reported outcomes questionnaires, clinical evaluation and instrumental tools offer complementary information in PIPN. Electrodiagnostic features include diffusely reduced/abolished sensory action potentials, in keeping with a sensory neuronopathy. PIPN is dependent on cumulative dose but there is a large variability in its occurrence. The search for additional risk factors for PIPN has thus far yielded no consistent findings. There are currently no neuroprotective strategies to reduce the risk of PIPN, and symptomatic treatment is limited to duloxetine that was found effective in a single phase III intervention study. This review critically examines the pathogenesis, incidence, risk factors (both clinical and pharmacogenetic), clinical phenotype and management of PIPN.

Effect of Aromatherapy Massage on Chemotherapy-Induced Peripheral Neuropathic Pain and Fatigue in Patients Receiving Oxaliplatin: An Open Label Quasi-Randomized Controlled Pilot Study

BACKGROUND

Patients receiving oxaliplatin may experience peripheral neuropathic pain and fatigue. Aromatherapy massage, a nonpharmacological method, may help to control these symptoms.

OBJECTIVE

The aim of this open-label, parallel-group, quasi-randomized controlled pilot study was to investigate the effect of aromatherapy massage on chemotherapy-induced peripheral neuropathic pain and fatigue in patients receiving oxaliplatin.

METHODS

Stratified randomization was used to allocate 46 patients to 2 groups: intervention (n = 22) and control (n = 24). Between week 1 and week 6, participants in the intervention group (IG) received aromatherapy massage 3 times a week. There was no intervention in weeks 7 and 8. The control group (CG) received routine care. Neuropathic pain was identified using the Douleur Neuropathique 4 Questions; severity of painful paresthesia was assessed with the numerical rating scale; fatigue severity was identified with the Piper Fatigue Scale.

RESULTS

At week 6, the rate of neuropathic pain was significantly lower in the IG, when compared with the CG. The severity of painful paresthesia based on numerical rating scale in the IG was significantly lower than that in the CG at weeks 2, 4, and 6. At week 8, fatigue severity in the IG was significantly lower when compared with CG (P < .05).

CONCLUSION

Aromatherapy massage may be useful in the management of chemotherapy-induced peripheral neuropathic pain and fatigue.

IMPLICATIONS FOR PRACTICE

This pilot study suggests that aromatherapy massage may be useful to relieve neuropathic pain and fatigue. However, there is a need for further clinical trials to validate the results of this study.

Variability of Oxaliplatin-Induced Neuropathic Pain Symptoms in Each Cycle and Its Implications on the Management of Colorectal Cancer Patients: A Retrospective Study in South Western Sydney Local Health District Hospitals, Sydney, Australia

Oxaliplatin-induced neuropathic pain limits treatment compliance. However, the variability of neuropathic pain symptoms in each cycle for individual patients and the impacts on treatment compliance remain untested. Data from 322 adult patients who received oxaliplatin-based chemotherapy were extracted based on pattern of chemotherapy, adverse events, and patient survival. Cox regression and survival analyses were employed. Seventy-eight percent of patients developed neuropathic pain that oscillated between a complete absence and presence on a cycle-by-cycle basis. Consequently, the presence of neuropathy in one cycle did not predict the incidence of neuropathy in subsequent cycles. This implies that neuropathic pain need not be a sufficient criterion to reduce, delay, or cease chemotherapy. In the case of multiple system adverse events during combined drug treatment, the responsible cause for dose reduction was not identified. Cox regression analysis revealed that middle age (61-78 years old, P=0.003) and oxaliplatin cumulative dose <850 mg/m2 (P=0.002) were associated with patient mortality. Completion of chemotherapy (8 cycles) and cumulative dose >850 mg/m2 of oxaliplatin prolonged the median survival time by 8 and 5 months, respectively. As oxaliplatin-induced neuropathic pain fluctuates across cycles in a manner that varies from patient-to-patient, current assumptions on the predictive nature of the emergence of neuropathy (and its impact on treatment compliance) need to be reconsidered. Detailed patient-by-patient analysis of adverse events should be applied to future studies in order to determine the efficacy of current treatments (and future interventions) and whether neuropathic pain should be retained as a criterion to vary the treatment. Additionally, when two or more system toxicities occurred in cases of combined drug treatment, the causes for drug reduction should be separately recorded.

L-Carnosine protects against Oxaliplatin-induced peripheral neuropathy in colorectal cancer patients: A perspective on targeting Nrf-2 and NF-κB pathways

BACKGROUND

Chemotherapy-induced peripheral neuropathy is a common side effect afflicting cancer patients treated with oxalipatin based chemotherapy.

AIM

The study investigated the potential prophylactic effect of L-carnosine against acute oxaliplatin neurotoxicity in colorectal cancer patients with emphasis on the redox (Nrf-2, MDA), inflammatory (NF-κB, TNF-α), and apoptotic (caspase-3) parameters.

METHODS

In this pilot study, 65 patients were recruited using a prospective randomized controlled study design and enrolled randomly into two arms; Arm A, 31 patients received FOLFOX-6 regimen (oxaliplatin, 5FU & leucovorin) and Arm B, 34 patients received FOLFOX-6 regimen and daily oral L-carnosine (500 mg) along the treatment period. Patients were followed up for three months, then both arms were analyzed for neuropathy incidence/grade and any additional toxicities according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTC version 4).

RESULTS

The neuropathy grading evaluation of Arm B vs Arm A revealed that 17 patients (56.7%) vs 11 patients (35.5%) suffered grade 1, one patient (3.3%) vs 19 patients (61.3%) suffered grade 2, while 12 patients (40%) vs one patient (3.2%) were normal. In arm B, the addition of L-carnosine decreased significantly the levels/activity of NF-κB (27%) and TNF-α (36.6%); this anti-inflammatory effect entailed also its anti-oxidative and anti-apoptotic effects, thus MDA level (51.8%) and caspase-3 activity (49%) were also reduced, whereas Nrf-2 was increased (38.7%) as compared to Arm A. In both arms a significant correlation was only evident between TNF-α and the neuropathy grading score (P < .03); the correlation analysis was significantly positive between NF-κB and both Nrf-2 and caspase 3.

CONCLUSION

L-Carnosine exerted a neuroprotective effect against oxaliplatin-induced peripheral neuropathy in colorectal cancer patients by targeting Nrf-2 and NF-κB pathways.

First-in-human phase I study of the microtubule inhibitor plocabulin in patients with advanced solid tumors

Background Plocabulin (PM060184) is a novel marine-derived microtubule inhibitor that acts as an antitumor agent. This first-in-human study evaluated dose-limiting toxicities (DLT) to define the maximum tolerated dose (MTD) and phase II recommended dose (RD) of plocabulin given as a 10-min infusion on Day (D) 1, D8 and D15 every four weeks. Patients and methods Forty-four patients with advanced solid tumors received plocabulin following an accelerated titration design. Results Plocabulin was escalated from 1.3 mg/m² to 14.5 mg/m², which was defined as the MTD. No RD was confirmed, because frequent dose delays and omissions resulted in low relative dose intensity (66%) at the 12.0 mg/m² expansion cohort. The main DLT was grade 3 peripheral sensory neuropathy (PSN); other DLTs were grade 4 tumor lysis syndrome, grade 4 cardiac failure and grade 3 myalgia. Toxicities were mainly mild to moderate, and included abdominal pain, myalgia, fatigue, nausea, and vomiting. Myelosuppression was transient and manageable. Plocabulin had a half-life of ~4 h and a wide diffusion to peripheral tissues. Antitumor response was observed in cervix carcinoma and heavily pretreated metastatic non-small cell lung cancer patients, and disease stabilization (≥3 months) in patients with colorectal, thymic, gastrointestinal stromal and breast tumors, among others. The clinical benefit rate was 33%. Conclusion The main DLT of plocabulin was PSN, as anticipated for a tubulin-binding agent. Since encouraging antitumor activity was observed, efforts to improve toxicity and to find the RD were planned in other trials evaluating D1&D8 and D1-D3 plus D15-D17 schedules.

Oxaliplatin induces pH acidification in dorsal root ganglia neurons

Oxaliplatin induced peripheral neurotoxicity is characterized by an acute cold-induced syndrome characterized by cramps, paresthesias/dysesthesias in the distal limbs and perioral region, that develops rapidly and lasts up to one week affecting nearly all the patients as well as by long-lasting symptoms. It has been previously shown that pharmacological or genetic ablation of TRPA1 responses reduces oxaliplatin-induced peripheral neurotoxicity in mouse models. In the present report, we show that treatment with concentrations of oxaliplatin similar to those found in plasma of treated patients leads to an acidification of the cytosol of mouse dorsal root ganglia neurons in culture and this in turn is responsible for sensitization of TRPA1 channels, thereby providing a mechanistic explanation to toxicity of oxaliplatin. Reversal of the acidification indeed leads to a significantly reduced activity of TRPA1 channels. Last, acidification occurs also in vivo after a single injection of therapeutically-relevant doses of oxaliplatin.

The incidence of acute oxaliplatin-induced neuropathy and its impact on treatment in the first cycle: a systematic review

BACKGROUND

Although acute oxaliplatin-induced neuropathy (OXIPN) is frequently regarded to be transient, recent studies have reported prolongation of infusion times, dose reduction and treatment cessation following the first dose of oxaliplatin in quarter of patients. Acute OXIPN is also a well-established risk factor for chronic neuropathy. However, there is underreporting of these parameters during the acute phase (≤ 14 days). This paper systematically reviews the incidence of acute OXIPN and its impact on treatment in the first cycle.

METHODS

A systematic literature search was performed using PubMed and Medline. Published original articles were included if they described details about prevalence of oxaliplatin-induced acute neuropathy.

RESULTS

Fourteen studies, comprised of 6211 patients were evaluated. The majority of patients were treated with oxaliplatin in combination with leucovorin and fluorouracil (FOLFOX). Most studies used the National Cancer Institute Common Toxicity Criteria to assess acute neuropathy. Acute neuropathy (Grades 1-4) was the most common event with prevalence ranging from 4-98%, followed by haematological (1.4-81%) and gastrointestinal (1.2-67%) toxicities, respectively. Drug regimens, starting dose of oxaliplatin and neuropathy assessment tools varied across studies. In addition, moderate to severe toxicities were common in patients that received a large dose of oxaliplatin (> 85 mg/m2) and/ or combined drugs. The majority of studies did not report the factors affecting acute neuropathy namely the range (minimal) doses required to evoke acute neuropathy, patient and clinical risk factors. In addition, there was no systematic reporting of the number of patients subjected to prolonged infusion, dose reduction, treatment delay and treatment cessation during the acute phase.

CONCLUSION

Despite the heterogeneity of studies regarding oxaliplatin starting dose, drug regimen, neuropathy assessment tools and study design, a large number of patients developed acute neuropathy. To develop a better preventive and therapeutic guideline for acute/chronic neuropathy, a prospective study should be conducted in a large cohort of patients in relation to drug regimen, starting/ranges (minimal) of doses producing acute neuropathy, treatment compliance, patient and clinical risk factors using a standardised neuropathy assessment tool.

A Prospective Study of Chronic Oxaliplatin-Induced Neuropathy in Patients with Colon Cancer: Long-Term Outcomes and Predictors of Severe Oxaliplatin-Induced Neuropathy

Background and Purpose

The objective of this study was to determine the incidence and long-term outcomes of oxaliplatin-induced peripheral neuropathy (OIPN), as well as predictors of its severe form.

Methods

Sixty-nine patients who were taking oxaliplatin for colon cancer were prospectively followed prior to starting chemotherapy and after 4, 8, and 12 cycles of chemotherapy. Thirty-six patients completed the follow-up at 1 year after the end of chemotherapy. The patients were assessed using clinical assessment scales and nerve conduction studies (NCS) at each follow-up visit.

Results

By applying the National Cancer Institute Common Toxicity criteria, OIPN was classified as grade 1 in 30 (44%) patients, grade 2 in 25 (36%), and grade 3 in 10 (14%) at the completion of therapy. At 1 year after the treatment, OIPN of grades 1, 2, and 3 was found in 50, 3, and 11% of the patients, respectively. Multivariate analysis showed that reductions of the amplitude of the sensory action potential of >11.5% in the median nerve between baseline and four cycles of chemotherapy (odds ratio=5.603, p=0.031) and of >22.5% in the sural nerve between four and eight cycles of chemotherapy (odds ratio=5.603, p=0.031) were independently associated with the risk of developing grade-3 OIPN.

Conclusions

While the severity of OIPN can improve after oxaliplatin discontinuation, more than half of the patients in this study still had OIPN at 1 year after discontinuation. Early changes in the NCS results for sensory nerves can predict the development of severe OIPN during treatment.

A rat model of FOLFOX-induced neuropathy: effects of oral dimiracetam in comparison with duloxetine and pregabalin

BACKGROUND AND AIM

The FOLFOX family of chemotherapy regimens are hampered by the development of a painful neuropathy. Current clinical treatments are inadequate, and furthermore, the research of innovative drugs is strongly disadvantaged by the absence of a preclinical model based on the complete mixture of FOLFOX components. The aim of this study was to set up a rat model of FOLFOX-induced neuropathy in rats, validate its predictability by reference drugs, and evaluate the effectiveness of the new anti-neuropathic compound dimiracetam.

METHODS

Male Sprague-Dawley rats were treated intraperitoneally with the FOLFOX components (6 mg kg^-1 oxaliplatin, 50 mg kg^-1 5-FU, 90 mg kg^-1 leucovorin calcium salt) or oxaliplatin alone (6 mg kg^-1) on days 0, 7, 14, and 21, whereas a separate group received one more injection of FOLFOX on day 28. Pain behavioural measurements (paw pressure, cold plate, and electronic Von Frey tests) and motor coordination (Rota-rod test) were assessed before and after treatments. Behavioural, motor, neurological, and autonomic parameters (open field and Irwin tests) were evaluated.

RESULTS

FOLFOX reduced the pain threshold in response to mechanical noxious and thermal (cold) non-noxious stimuli beginning from day 14 up to day 42 comparably to oxaliplatin alone. A fifth FOLFOX injection enhanced the severity but not the duration of painful alterations. Spontaneous activity, behavioural, autonomic, and neurological functions were also affected, whereas the motor coordination was not altered. On day 22, duloxetine (15 mg kg^-1, per os), morphine (10 mg kg^-1, subcutaneously), or pregabalin (20 mg kg^-1, per os), acutely administered, reduced the FOLFOX-dependent hypersensitivity. Repeated treatments with dimiracetam (150 mg kg^-1, per os, twice daily, from day 22) significantly protected rats from FOLFOX-induced alterations of pain threshold as well as from autonomic and neurological impairments taking effect after 7 days treatment. Pregabalin repeatedly administered (20 mg kg^-1, per os, twice daily, from day 22) was less effective in reducing mechanical hypersensitivity.

CONCLUSION

A clinically consistent model of FOLFOX-induced neurotoxicity has been developed in rats. Dimiracetam fully reduced hypersensitivity and neurological alterations showing a relevant profile as anti-neuropathic resource.

Genetic polymorphisms of SCN9A are associated with oxaliplatin-induced neuropathy

Background

Oxaliplatin is a chemotherapy agent active against digestive tumors. Peripheral neuropathy is one of the most important dose-limiting toxicity of this drug. It occurs in around 60–80% of the patients, and 15% of them develop severe neuropathy. The pathophysiology of oxaliplatin neurotoxicity remains unclear. SCN9A is a gene codifying for a subtype sodium channel (type IX, subunit α) and mutations in this gene are involved in neuropathic perception. In this study we investigated whether SCN9A genetic variants were associated with risk of neurotoxicity in patients diagnosed of cancer on treatment with oxaliplatin.

Methods

Blood samples from 94 patients diagnosed of digestive cancer that had received oxaliplatin in adjuvant or metastatic setting were obtained from three hospitals in Madrid. These patients were classified into two groups: “cases” developed oxaliplatin-induced grade 3–4 neuropathy (n = 48), and “controls” (n = 46) had no neuropathy or grade 1. The neuropathy was evaluated by an expert neurologist and included a clinical examination and classification according to validated neurological scales: National Cancer Institute Common Toxicity Criteria (NCI-CTC), Oxaliplatin-Specific Neurotoxicity Scale (OSNS) and Total Neuropathy score (TNS). Genotyping was performed for 3 SCN9A missense polymorphisms: rs6746030 (R1150W), rs74401238 (R1110Q) and rs41268673 (P610T), and associations between genotypes and neuropathy were evaluated.

Results

We found that SCN9A rs6746030 was associated with protection for severe neuropathy (OR = 0.39, 95% CI = 0.16–0.96; p = 0.041). Multivariate analysis adjusting for diabetes provided similar results (p = 0.036). No significant differences in neuropathy risk were detected for rs74401238 and rs41268673.

Conclusion

SCN9A rs6746030 was associated with protection for severe oxaliplatin-induced peripheral neuropathy. The validation of this exploratory study is ongoing in an independent series.

Oxaliplatin-induced Peripheral Neuropathy in South Indian Cancer Patients: A Prospective Study in Digestive Tract Cancer Patients

Purpose:

The aim of the current study is to report our prospective experience on the prevalence of oxaliplatin-induced peripheral neuropathy (OXAIPN) in patients with digestive tract cancers treated with oxaliplatin-based combination therapy.

Materials and Methods:

A total of 219 patients scheduled to be treated with oxaliplatin-based combination therapy were prospectively examined at baseline and follow-up during the therapy between November 2014 and December 2016. The incidence of acute OXAIPN was measured using a descriptive questionnaire (yes/no question) based on sum of number of symptoms present and NCI-CTCAE version 4.03 was applied to clinically grade the severity of chronic OXAIPN.

Results:

Acute and chronic OXAIPN was found in 108 of 219 (49.3%) and 127 of 219 (58%) patients, respectively. Out of 11 acute OXAIPN symptoms, the vast majority of patients manifested cold-induced pharyngolaryngeal (63.8%) dysesthesias or perioral (61.1%) paresthesias. Development of acute OXAIPN was predictive of subsequent development of chronic OXAIPN (P = 0.0001). All the patients received a median cumulative dose of 780 mg/m² (range: 130–1040 mg/m²). There was a significant correlation between the patients who received the median cumulative dose and the development of chronic OXAIPN. The incidences of OXAIPN in patients with median cumulative dose of ≤780 mg/m² was 51/120 (42.5%) and >780 mg/m² was OXAIPN 76/99 (76.7%) (P = 0.0001).

Conclusion:

The current study results demonstrate that the vast majority of patients who receive oxaliplatin-based combination chemotherapy will manifest acute OXAIPN that may contribute to the development of chronic peripheral neuropathy on repeated courses of drug administration.

A prospective study to evaluate the efficacy and safety of oral acetyl-L-carnitine for the treatment of chemotherapy-induced peripheral neuropathy

The present study aimed to evaluate the efficacy and safety of acetyl-L-carnitine (ALC) for the treatment of chemotherapy-induced peripheral neuropathy (CIPN). The study was carried out as a prospective, randomized, double-blind, placebo-controlled and paralleled clinical study. A total of 239 patients with CIPN were selected as the study subjects. Of the 239 subjects, 118 subjects received 3 g/day ALC orally for 8 weeks and 121 received a placebo. The primary endpoint was improvement of peripheral neuropathy by at least one grade. Patient status was assessed at week 4, 8 and 12 after enrollment into the study. In both the full analysis set (FAS) and the per-protocol set (PPS), peripheral sensory neuropathy was significantly ameliorated in the ALC group with 50.5 and 51.6% patients meeting the primary endpoint at week 8, compared with 24.1 and 23.1% of patients in the placebo group (P<0.001 in both sets). Secondary endpoints, such as the nerve electrophysiological examination and the Karnofsky physical score were also significantly improved in patients receiving ALC treatment, as compared with the placebo group (FAS, P=0.0463 and P=0.022; PPS, P=0.0076 and P=0.0064, respectively). Cancer-associated fatigue was significantly alleviated following ALC treatment in the PPS (P=0.0135). In the safety analysis set, the difference in adverse events incidence between the two groups was not statistically significant (P=0.3903). There were only two severe adverse events in the ALC group, which were not associated with the effect of ALC. In conclusion, the results of the present study demonstrated that in Chinese patients with cancer, oral administration of ALC is effective at ameliorating peripheral sensory neuropathy induced by chemotherapy, as well as reducing of cancer-associated fatigue and improving physical conditions.

Behavioral and electromyographic assessment of oxaliplatin-induced motor dysfunctions: Evidence for a therapeutic effect of allopregnanolone

The antineoplastic oxaliplatin (OXAL) is pivotal for metastatic cancer treatments. However, OXAL evokes sensory and motor side-effects including pain, muscle weakness, motor nerve fiber dysfunctions/neuropathies that significantly impact patients' lives. Therefore, preclinical investigations are struggling to characterize effective analgesics against OXAL-induced painful/sensory symptoms but surprisingly, OXAL-evoked motor dysfunctions received little attention although these neurological symptoms are also disabling for patients. Here, we validated a rat model of OXAL-induced motor neuropathy by using (i) behavioral methods as the wire suspension and balance beam tests to assess muscle weakness and (ii) electrophysiological techniques to record the gastrocnemius electromyography (EMG). The conductance velocity of motor fibers was reduced and compound muscle action potential (CMAP) duration increased in OXAL-treated rats, leading to CMAP dispersion with no modification of the area under the curve, reflecting a heterogeneous demyelination of motor fibers. Functional motor unit analysis revealed a 50 % decrease of their estimated number which was compensated by a motor unit size increase. OXAL-induced motor weakness appeared as a combined consequence of motor fiber demyelination and motor axonopathy. Because we previously observed that allopregnanolone (AP) counteracted OXAL-evoked painful/sensory symptoms, we evaluated its action against OXAL-induced motor neurological dysfunctions. AP treatment successfully corrected motor behaviors, conductance velocity, CMAP duration, motor unit number (MUN) and motor unit size altered by OXAL-chemotherapy. These results, which are the first to show that AP efficiently rescues OXAL-induced motor neuropathy, consolidate the idea that AP-based therapy may be relevant for the treatment of both sensory and motor peripheral neuropathies.

Oxaliplatin added to fluoropyrimidine for adjuvant treatment of colorectal cancer is associated with long-term impairment of peripheral nerve sensory function and quality of life

BACKGROUND

Oxaliplatin-induced peripheral neuropathy (OIPN) of acute and chronic type is well known, but long-term chronic type OIPN and its impact on quality of life (QoL) has not been extensively studied. Clinical experience indicates that oxaliplatin tolerance might vary with climate.

MATERIAL AND METHODS

Patient-reported chronic type OIPN and QoL among patients treated with oxaliplatin added to a fluoropyrimidine (Folfox or Capox) in the adjuvant setting of colorectal cancer (CRC) were assessed in a single center cross-sectional study by using the EORTC QLQ-CIPN20 and QLQ-C30 questionnaires. Comparison was made to patients treated with a fluoropyrimidine (5-FU or capecitabine) alone during the same time period.

RESULTS

Of 161 patients being disease-free 1-8 years after stop of treatment and invited, 84% participated; 65 treated with oxaliplatin and 71 with a fluoropyrimidine alone. Mean cumulative oxaliplatin dose was 567 mg/m² (55% of planned dose). Oxaliplatin-treated patients reported statistically and clinically significant worse sensory as well as motor scale scores, dominated by symptoms from the feet. Severe tingling and numbness in toes/feet was reported by 38% and 37%, respectively, by oxaliplatin-treated patients compared with 8% for both by fluoropyrimidine alone patients (p < 0.001). Subgroup analyses indicated no impact of gender, age, regimen, time since stop of treatment or cumulated oxaliplatin dose for severity of the chronic type OIPN. The oxaliplatin compared with the fluoropyrimidine group reported worse QoL scores throughout all domains, with statistically and clinically significant differences for role and social function, nausea/loss of appetite and financial problems.

CONCLUSIONS

Oxaliplatin added to a fluoropyrimidine for adjuvant treatment of CRC in a country with subarctic climate is associated with long-term, seemingly chronic, sensory neuropathy and impairment of QoL. This should be taken into account in clinical decision making on oxaliplatin treatment in the adjuvant setting.

Large-scale prospective pharmacogenomics study of oxaliplatin-induced neuropathy in colon cancer patients enrolled in the JFMC41-1001-C2 (JOIN Trial)

BACKGROUND

Peripheral sensory neuropathy (PSN) is a dose-limiting toxicity of oxaliplatin-based chemotherapy. Several genetic markers have been shown to predict oxaliplatin-induced PSN; however, results remain to be validated in a large-scale and prospective pharmacogenomics study.

PATIENTS AND METHODS

Among 882 patients enrolled in the JFMC41-1001-C2 (JOIN trial), which was designed to investigate the tolerability of adjuvant-modified FOLFOX6 (mFOLFOX6) in Japanese Patients with stage II or III colon cancers undergoing curative resection, 465 patients were eligible for this pharmacogenomics analysis. Twelve single-nucleotide polymorphisms (SNPs) were selected based on published data. The effect of each genotype on time to PSN onset was evaluated in all patients (n = 465) using the Cox proportional hazard model. For the association analysis between severity of PSN and 12 SNP markers, 84 patients who failed to complete 12 cycles of mFOLFOX6 from grade 0/1 PSN group were excluded because the termination of the protocol treatment had been caused by reasons other than PSN.

RESULTS

Comparison of grade 0/1 PSN with grade 2/3 PSN or grade 3 PSN showed no significant associations with any of the 12 SNP markers after adjustment for total dose of oxaliplatin. Time-to-onset analysis also failed to reveal any significant differences.

CONCLUSIONS

Our large-scale and prospective pharmacogenomics study of Japanese patients receiving protocol treatment of adjuvant mFOLFOX6 could not verify a role for any of the 12 SNP markers reported as being significantly associated with PSN. Considering the OR observed in this study (range: 0.76-1.89), further evaluation of these 12 SNP markers in the context of L-OHP-induced PSN is unlikely to be clinically informative.

Quick, non-invasive and quantitative assessment of small fiber neuropathy in patients receiving chemotherapy

Chemotherapy-induced peripheral neurotoxicity (CIPN) is a common, potentially severe and dose-limiting adverse effect; however, it is poorly investigated at an early stage due to the lack of a simple assessment tool. As sweat glands are innervated by small autonomic C-fibers, sudomotor function testing has been suggested for early screening of peripheral neuropathy. This study aimed to evaluate Sudoscan, a non-invasive and quantitative method to assess sudomotor function, in the detection and follow-up of CIPN. Eighty-eight patients receiving at least two infusions of Oxaliplatin only (45.4%), Paclitaxel only (14.8%), another drug only (28.4%) or two drugs (11.4%) were enrolled in the study. At each chemotherapy infusion the accumulated dose of chemotherapy was calculated and the Total Neuropathy Score clinical version (TNSc) was carried out. Small fiber neuropathy was assessed using Sudoscan (a 3-min test). The device measures the Electrochemical Skin Conductance (ESC) of the hands and feet expressed in microSiemens (µS). For patients receiving Oxaliplatin mean hands ESC changed from 73 ± 2 to 63 ± 2 and feet ESC from 77 ± 2 to 66 ± 3 µS (p < 0.001) while TNSc changed from 2.9 ± 0.5 to 4.3 ± 0.4. Similar results were observed in patients receiving Paclitaxel or another neurotoxic chemotherapy. During the follow-up, ESC values of both hands and feet with a corresponding TNSc < 2 were 70 ± 2 and 73 ± 2 µS respectively while they were 59 ± 1.4 and 64 ± 1.5 µS with a corresponding TNSc ≥ 6 (p < 0.0001 and p = 0.0003 respectively). This preliminary study suggests that small fiber neuropathy could be screened and followed using Sudoscan in patients receiving chemotherapy.

Long-term course of oxaliplatin-induced polyneuropathy: a prospective 2-year follow-up study

This prospective study sought to identify the potential reversibility of oxaliplatin-induced peripheral neuropathy (OXAIPN) by following-up its long-term course 2 years after discontinuation of oxaliplatin (OXA)-based chemotherapy. Participants were 91 colorectal cancer patients treated with OXA-based chemotherapy. Neurological assessment, clinical Total Neuropathy Score© (TNSc©) and nerve conduction studies were performed at baseline (T0), the end of chemotherapy (T1) and 2 years (T2) after discontinuation of chemotherapy. A total of 73 of 91 (80%) patients experienced OXAIPN at T1. At a median follow-up of 25 months, persistence of chronic OXAIPN was present in 61 of 73 patients (84%) and complete resolution was present in 12 patients (17%). Longitudinal comparison of TNSc© values between T1 and T2 revealed that the overall severity of OXAIPN in those 61 patients significantly decreased over time. Median TNSc© values were nine (range: 2-15) at T1 vs. four (range: 2-12) at T2 (P < 0.001). Likewise, sensory nerve conduction measures at T2 significantly improved in all sensory nerves tested, compared with T1. Severity of OXAIPN at T2 was significantly associated (P < 0.001) with high severity of OXAIPN at T1. In conclusion, persistence of OXAIPN beyond 2 years after finishing chemotherapy is common. Clinical and neurophysiological improvement is observed, although recovery is often incomplete.