Clinical management of oxaliplatin-associated neurotoxicity

Analysis of reduced-dose administration of oxaliplatin as adjuvant FOLFOX chemotherapy for colorectal cancer

Purpose

An oxaliplatin-based regimen is the most common adjuvant chemotherapy for patients with stage II/III colorectal cancer, but many patients experience dose reduction or early termination of chemotherapy due to side effects. We conducted this study to verify the range of reduction with oncologic safety.

Methods

Patients with stage II/III colorectal cancer who received adjuvant FOLFOX chemotherapy were enrolled in this study. The total amount of oxaliplatin administered per patient was calculated as a percentile based on 12 cycles of full-dose FOLFOX as a standard dose. The cutoff values showing significant differences in survival were calculated, and the clinicopathologic outcomes of patient groups classified by the value were compared.

Results

Among a total of 611 patients, there were 107 stage II patients, and 504 stage III patients. At 60% of the standard dose of oxaliplatin, the patients in the dose reduction group were older (62 years vs. 58 years, P = 0.003), had lower body mass index (BMI) (23.1 kg/m²vs. 24.0 kg/m², P = 0.005), and were more exposed to neoadjuvant treatment (18.0% vs. 9.1%, P = 0.003) in comparison to the standard group. At 60% of the standard dose, there were no significant differences in 5-year disease-free survival (DFS) and overall survival (OS) between the 2 groups (5-year DFS: 73.5% vs. 74.2%, P = 0.519; 5-year OS: 71.9% vs. 81.5%, P = 0.256, respectively).

Conclusion

Patients with old age, low BMI, and more frequent exposure to neoadjuvant treatment tended to show lower compliance with chemotherapy. More than 60% dose should be administered to patients with stage II/III colorectal cancer as adjuvant chemotherapy to achieve acceptable oncologic outcomes.

Changes in upper extremity function, ADL, and HRQoL in colorectal cancer patients after the first chemotherapy cycle with oxaliplatin: a prospective single-center observational study

PURPOSE

Oxaliplatin, an important chemotherapeutic agent in colorectal cancer, causes chemotherapy-induced peripheral neuropathy (CIPN), for which prophylactic or therapeutic interventions are lacking. We aimed to investigate changes in upper extremities, activities of daily living (ADL), and health-related quality of life (HRQoL) parameters after the first chemotherapy cycle.

METHODS

Thirty-eight colorectal cancer patients scheduled to receive the leucovorin, 5'-fluorouracil, oxaliplatin (FOLFOX) therapy or the capecitabine, oxaliplatin (CAPOX) therapy, participated. Patients underwent objective assessment of sensory function, muscular strength, and manual dexterity and answered the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) and the Disabilities of the Arm, Shoulder, and Hand-Disability/Symptom (DASH-DS) questionnaires for subjective assessment. The CIPN was assessed at baseline and prior to the second drug cycle.

RESULTS

Light touch sensation in both hands worsened significantly after the first drug cycle, though no significant changes were observed in muscular strength and manual dexterity. The QLQ-C30 analysis showed that Physical Functioning, Role Functioning, Nausea and Vomiting, and Dyspnea were significantly worse, whereas Emotional Functioning was improved. The DASH-DS analysis revealed significant worsening of dysfunction and subjective symptoms.

CONCLUSIONS

Our results suggest that light touch sensation may worsen even in the absence of multiple chemotherapy cycles. Even if arm and hand function (muscular strength and manual dexterity) is apparently intact, patients may experience dysfunction and decreased HRQoL. For preserving or improving patients' ADL and HRQoL, it is imperative to provide support at chemotherapy initiation.

Association of Voltage-Gated Sodium Channel Genetic Polymorphisms with Oxaliplatin-Induced Chronic Peripheral Neuropathy in South Indian Cancer Patients

Oxaliplatin is a platinum drug active against digestive tract cancers. Among its side effects, peripheral neuropathy is one of the dose-limiting toxicities. This affects around 50 to 70% of patients but the pathophysiology of development of oxaliplatin-induced peripheral neuropathy (OXAIPN) remains unclear. Sodium channels (SCNAs) play major role in neuronal electrical signaling processes and mutations in SCNAs lead to various neuronal diseases involving the central and peripheral nervous systems. In this study, we evaluated whether SCNA genetic variants might be associated with risk of chronic OXAIPN in patients with digestive tract cancers treated with oxaliplatin. Methodology: Blood samples from 228 digestive tract cancer patients who had received oxaliplatin in adjuvant and neoadjuvant or metastatic settings were obtained and genomic DNA was extracted by phenol-chloroform extraction. Genotyping was performed with the real-time polymerase chain reaction (RT-PCR) using validated real-time TaqMan single nucleotide polymorphism (SNP) genotyping assays. Neuropathy was evaluated and graded according to National Cancer Institute Common Toxicity Criteria (NCI-CTC) version 4.03. Results: We found that the rs6746030 polymorphic variant of SCN9A was significantly associated with a higher incidence of chronic OXAIPN (GA+AA vs GG: OR=1.8, 95% CI=1.04-3.4, P=0.04; dominant model) while the rs6754031 variant was linked with a lower incidence (OR=0.45, 95% CI=0.22-0.77, P=0.005; dominant model). The SCN 10A polymorphic variant was associated with severity of chronic OXAIPN (P=0.006, OR=2.0, 95% CI=1.2 - 3.3). Conclusion: The results of the present prospective study provide evidence in support of a causal relationship between chronic OXAIPN and voltage gated sodium channel polymorphisms. However, further studies from independent groups are required to validate these results.

Lipoyl-Homotaurine Derivative (ADM_12) Reverts Oxaliplatin-Induced Neuropathy and Reduces Cancer Cells Malignancy by Inhibiting Carbonic Anhydrase IX (CAIX)

Oxaliplatin (OXA) is a valuable and largely used cancer drug which induces a serious and intractable neuropathy. The lipoyl-homotaurine derivative (ADM_12) reverts in vivo OXA-induced neuropathy, and it is an effective antagonist of the nociceptive sensor channel TRPA1. Unprecedentedly, this safe analgesic showed a synergy with OXA in vitro and proved to inhibit CA IX, a relevant therapeutic target, clearly interfering with pancreatic cancer cells' aggressiveness.

Dorsal root ganglia hypertrophy as in vivo correlate of oxaliplatin-induced polyneuropathy

Purpose

To investigate in vivo morphological and functional correlates of oxaliplatin-induced peripheral neuropathy (OXA-PNP) by magnetic resonance neurography (MRN).

Methods

Twenty patients (7 female, 13 male, 58.9±10.0 years) with mild to moderate OXA-PNP and 20 matched controls (8 female, 12 male, 55.7±15.6 years) were prospectively enrolled. All patients underwent a detailed neurophysiological examination prior to neuroimaging. A standardized imaging protocol at 3.0 Tesla included the lumbosacral plexus and both sciatic nerves and their branches using T2-weighted fat-saturated sequences and diffusion tensor imaging. Quantitative assessment included volumetry of the dorsal root ganglia (DRG), sciatic nerve normalized T2 (nT2) signal and caliber, and fractional anisotropy (FA), mean diffusivity (MD), axial (AD) and radial diffusivity (RD). Additional qualitative evaluation of sciatic, peroneal, and tibial nerves evaluated the presence, degree, and distribution of nerve lesions.

Results

DRG hypertrophy in OXA-PNP patients (207.3±47.7mm³ vs. 153.0±47.1mm³ in controls, p = 0.001) was found as significant morphological correlate of the sensory neuronopathy. In contrast, peripheral nerves only exhibited minor morphological alterations qualitatively. Quantitatively, sciatic nerve caliber (27.3±6.7mm² vs. 27.4±7.4mm², p = 0.80) and nT2 signal were not significantly changed in patients (1.32±0.22 vs. 1.22±0.26, p = 0.16). AD, RD, and MD showed a non-significant decrease in patients, while FA was unchanged.

Conclusion

OXA-PNP manifests with morphological and functional correlates that can be detected in vivo by MRN. We report hypertrophy of the DRG that stands in contrast to experimental and postmortem studies. DRG volume should be further investigated as a biomarker in other sensory peripheral neuropathies and ganglionopathies.

The Role of Transporters in the Toxicity of Chemotherapeutic Drugs: Focus on Transporters for Organic Cations

The introduction of chemotherapy in the treatment of cancer is one of the most important achievements of modern medicine, even allowing the cure of some lethal diseases such as testicular cancer and other malignant neoplasms. The number and type of chemotherapeutic agents available have steadily increased and have developed until the introduction of targeted tumor therapy. It is now evident that transporters play an important role for determining toxicity of chemotherapeutic drugs not only against target but also against nontarget cells. This is of special importance for intracellularly active hydrophilic drugs, which cannot freely penetrate the plasma membrane. Because many important chemotherapeutic agents are substrates of transporters for organic cations, this review discusses the known interaction of these substances with these transporters. A particular focus is given to the role of transporters for organic cations in the development of side effects of chemotherapy with platinum derivatives and in the efficacy of recently developed tyrosine kinase inhibitors to specifically target cancer cells. It is evident that specific inhibition of uptake transporters may be a possible strategy to protect against undesired side effects of platinum derivatives without compromising their antitumor efficacy. These transporters are also important for efficient targeting of tyrosine kinase inhibitors to cancer cells. However, in order to achieve the aims of protecting from undesired toxicities and improving the specificity of uptake by tumor cells, an exact knowledge of transporter expression, function, regulation under normal and pathologic conditions, and of genetically and epigenetically regulation is mandatory.

Factors associated with the development and severity of oxaliplatin-induced peripheral neuropathy: a systematic review

Oxaliplatin is a platinum-derivative chemotherapeutic agent used for colorectal cancer in the adjuvant and metastatic setting in combination with folinic acid and 5-fluorouracil. Oxaliplatin causes an acute cold-induced neurotoxicity and a chronic cumulative neuropathy, which can require dose modification and impact quality of life. To date, no prevention and treatment strategies have proved effective thus reinforcing the importance of identifying at-risk patients in order to maximize therapeutic benefit while minimizing neurotoxicity. Here we reviewed studies on risk and prognostic factors associated with the development and severity of oxaliplatin-induced peripheral neuropathy. A systematic search was conducted in MEDLINE and Embase, and studies investigating clinical and patient-related factors associated with oxaliplatin-induced peripheral neuropathy as their primary focus were identified, and quantitative data were extracted when available. We identified 15 studies, of which only three were prospective. Notable factors were acute neurotoxicity symptoms predicting chronic neuropathy, baseline laboratory findings, patient demographics such as age and gender, comorbidities, and environmental factors. No factor was consistently identified across multiple studies other than the association with oxaliplatin dose. Further investigation into these factors may yield insight into potential neuropathy prevention and treatment strategies.

Resveratrol alleviates oxidative damage in enteric neurons and associated gastrointestinal dysfunction caused by chemotherapeutic agent oxaliplatin

Oxaliplatin is a first-line chemotherapeutic agent used for the treatment of colorectal cancer. Its use is associated with severe gastrointestinal (GI) side-effects, associated with oxidative damage and neurotoxicity to the enteric neurons. Resveratrol is a potent anti-oxidant that has been shown to protect against oxidative damage and neurotoxicity in other neurons and could therefore prevent oxaliplatin-induced damage to enteric neurons. We determined whether co-administration of resveratrol with oxaliplatin alleviates enteric neuron toxicity and GI dysfunction in mice. Colons were collected for immunohistochemical analysis of myenteric neurons and assessment of motor activity in organ-bath experiments. Morphological damage to the colonic mucosa and muscles was analysed. Oxaliplatin treatment induced translocation of nitrated proteins into the nuclei of myenteric neurons and significant damage to the mucosal lining, vacuolisation and a decrease in muscle thickness. This damage is linked to motor dysfunction due to inhibition of the amplitude of colonic contractions, leading to chronic constipation. Co-treatment with resveratrol prevented oxaliplatin-induced neurotoxicity, alleviated damage to GI mucosa, crypts and muscle layer, resulting in improved contractility and a decrease in constipation. Resveratrol could be integrated as part of a therapeutic regimen to help alleviate oxaliplatin-induced GI dysfunction.

[Properties of the Measures to Assess Oxaliplatin-induced Peripheral Neuropathy: A Literature Review]

PURPOSE

The purpose of this study is to provide a comprehensive overview of the various measures available for assessment of oxaliplatin-induced peripheral neuropathy (OXLIPN) and to evaluate the measurement properties of each assessment tool.

METHODS

A systematic review was conducted to identify existing measures for OXLIPN found in the databases of PubMed, Cochrane Library, Embase, RISS and KoreaMed. The quality of the 24 identified tools was evaluated based on their properties of measurement including content validity, internal consistency, criterion validity, construct validity, reproducibility, responsiveness, floor-ceiling effects and interpretability.

RESULTS

Ten (41.7%) of the 24 tools were identified as specific measures for assessing OXLIPN and the most popular type of measures were clinical grading systems by clinicians (58.3%) and only 29.2% of measures were identified as patient reported outcomes. The most frequently used tool was National Cancer Institute-Common Toxicity Criteria (NCI-CTC), but the validity of NCI-CTC has not been reported appropriately. Overall, the Neuropathic Pain Symptom Inventory (NPSI) received the best psychometric scores, and the Chemotherapy-induced Peripheral Neuropathy Assessment Tool (CIPNAT) and Functional Assessment of Cancer Therapy/Gynaecologic Oncology Group-neurotoxicity-12 (FACT/GOG-Ntx-12) followed NPSI.

CONCLUSION

To select appropriate measure, evidences should be accumulated through the clinical use of tools. Therefore, practitioner and researchers are urged to report relevant statistics required for the validation of the currently used measures for assessment of OXLIPN.

Therapeutic Effects of Phytochemicals and Medicinal Herbs on Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a frequent adverse effect of neurotoxic anticancer medicines. It leads to autonomic and somatic system dysfunction and decreases the patient's quality of life. This side effect eventually causes chemotherapy non-compliance. Patients are prompted to seek alternative treatment options since there is no conventional remedy for CIPN. A range of medicinal herbs have multifarious effects, and they have shown some evidence of efficacy in various neurological and immunological diseases. While CIPN has multiple mechanisms of neurotoxicity, these phytomedicines might offer neuronal protection or regeneration with the multiple targets in CIPN. Thus far, researchers have investigated the therapeutic benefits of several herbs, herbal formulas, and phytochemicals in preventing the onset and progress of CIPN in animals and humans. Here, we summarize current knowledge regarding the role of phytochemicals, herb extracts, and herbal formulas in alleviating CIPN.

Adjuvant FOLFOX treatment for stage III colon cancer: how many cycles are enough?

Purpose

Adjuvant FOLFOX (5-fluorouracil and oxaliplatin) chemotherapy benefits stage III colon cancer patients. However, it still results in side effects and increased cost. Reducing cycles had been thought to decrease these problems. This retrospective study aimed to find the appropriate number of treatment cycles that are sufficient for treating these patients.

Patients and methods

A total of 213 stage III colon cancer patients receiving adjuvant FOLFOX therapy were retrospectively recruited. Demographic data were collected for analysis. Survival analyses were performed between all cases of patients receiving above and below a certain cycle number. If a significant difference was reached at that cycle number, multivariate Cox Regression was performed with those factors resulting in p < 0.2 to assess the independent prognostic factors.

Results

The 5-year overall survival rate of patients was 77.9 %, and the 3-year disease-free survival was 76.7 %. For overall survival, a significant benefit was noted for treatment of at least 8 cycles, for disease-free survival, significant differences were apparent from patient data of those who underwent from 7 to 12 treatment cycles. Multivariate survival analysis of that patient data at cycle 8 for overall survival and cycle 7 for disease free survival revealed cycle number as the only independent prognostic factor (p = 0.04, 0.048).

Conclusion

Cycle number of adjuvant FOLFOX is a significant prognostic factor for stage III colon cancer patients. At least 8 cycles are needed to have an overall survival benefit, and 7 to disease-free survival.

Exenatide Facilitates Recovery from Oxaliplatin-Induced Peripheral Neuropathy in Rats

Background

Oxaliplatin has widely been used as a key drug in the treatment of colorectal cancer; however, it causes peripheral neuropathy. Exenatide, a glucagon-like peptide-1 (GLP-1) agonist, is an incretin mimetic secreted from ileal L cells, which is clinically used to treat type 2 diabetes mellitus. GLP-1 receptor agonists have been reported to exhibit neuroprotective effects on the central and peripheral nervous systems. In this study, we investigated the effects of exenatide on oxaliplatin-induced neuropathy in rats and cultured cells.

Methods

Oxaliplatin (4 mg/kg) was administered intravenously twice per week for 4 weeks, and mechanical allodynia was evaluated using the von Frey test in rats. Axonal degeneration was assessed by toluidine blue staining of sciatic nerves.

Results

Repeated administration of oxaliplatin caused mechanical allodynia from day 14 to 49. Although the co-administration of extended-release exenatide (100 μg/kg) could not inhibit the incidence of oxaliplatin-induced mechanical allodynia, it facilitated recovery from the oxaliplatin-induced neuropathy with reparation of axonal degeneration. Inhibition of neurite outgrowth was evaluated in cultured pheochromocytoma 12 (PC12) cells. Exenatide inhibited oxaliplatin-induced neurite degeneration, but did not affect oxaliplatin-induced cell injury in cultured PC12 cells. Additionally, extended-release exenatide had no effect on the anti-tumor activity of oxaliplatin in cultured murine colon adenocarcinoma 26 (C-26) cells or C-26 cell-implanted mice.

Conclusion

These results suggest that exenatide may be useful for treating peripheral neuropathy induced by oxaliplatin in colorectal cancer patients with type 2 diabetes.

Recent Advances in Platinum (IV) Complex-Based Delivery Systems to Improve Platinum (II) Anticancer Therapy

Cisplatin and its platinum (Pt) (II) derivatives play a key role in the fight against various human cancers such as testicular, ovarian, head and neck, lung tumors. However, their application in clinic is limited due to dose- dependent toxicities and acquired drug resistances, which have prompted extensive research effort toward the development of more effective Pt (II) delivery strategies. The synthesis of Pt (IV) complex is one such an area of intense research fields, which involves their in vivo conversion into active Pt (II) molecules under the reducing intracellular environment, and has demonstrated encouraging preclinical and clinical outcomes. Compared with Pt (II) complexes, Pt (IV) complexes not only exhibit an increased stability and reduced side effects, but also facilitate the intravenous-to-oral switch in cancer chemotherapy. The overview briefly analyzes statuses of Pt (II) complex that are in clinical use, and then focuses on the development of Pt (IV) complexes. Finally, recent advances in Pt (IV) complexes in combination with nanocarriers are highlighted, addressing the shortcomings of Pt (IV) complexes, such as their instability in blood and irreversibly binding to plasma proteins and nonspecific distribution, and taking advantage of passive and active targeting effect to improve Pt (II) anticancer therapy.

Mechanisms involved in the development of chemotherapy-induced neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating and painful condition seen in patients undergoing treatment with common agents such as vincristine, paclitaxel, oxaliplatin and bortezomib. The mechanisms of this condition are diverse, and include an array of molecular and cellular contributions. Current research implicates genetic predispositions to this condition, which then may influence cellular responses to chemotherapy. Processes found to be influenced during CIPN include increased expression of inflammatory mediators, primarily cytokines, which can create cascading effects in neurons and glia. Changes in ion channels and neurotransmission, as well as changes in intracellular signaling and structures have been implicated in CIPN. This review explores these issues and suggests considerations for future research.

First-line gemcitabine and oxaliplatin (GEMOX) plus sorafenib, followed by sorafenib as maintenance therapy, for patients with advanced hepatocellular carcinoma: a preliminary study

BACKGROUND

Because of the poor prognosis of unresectable or metastatic hepatocellular carcinoma there is a need for effective systemic therapy. The purpose of this study was to assess the efficacy and safety of gemcitabine and oxaliplatin (GEMOX) combined with sorafenib, as first-line therapy, followed by sorafenib as maintenance therapy for patients with advanced hepatocellular carcinoma (HCC).

METHODS

In this open-label, multicenter, single-group, prospective study, eligible patients with advanced HCC received oral sorafenib 400 mg twice daily, gemcitabine 1,000 mg/m(2) intravenously (i.v.) on day 1 and oxaliplatin 85 mg/m(2) i.v. on day 2 every 14 days for up to six cycles. Patients without disease progression were then treated further with sorafenib as maintenance therapy until disease progression.

RESULTS

All forty-nine patients completed six cycles of combined GEMOX and sorafenib therapy. The objective response was 26.5 %. The median time to progression was 10.3 months (95 % CI: 8.7-11.9 months) and median overall survival was 15.7 months (95 % CI: 13.0-18.4 months). During the combination therapy, the most common grade 3/4 hematologic toxicity was neutropenia (22.4 %, 11/49 patients) and thrombocytopenia (14.3 %, 7/49 patients); grade 3/4 non-hematologic toxicity was fatigue (22.4 %, 11/49 patients) and appetite loss (18.4 %, 9/49 patients). During the maintenance therapy, grade 3/4 adverse events were nonhematologic toxicity, for example fatigue (16.0 %, 4/25 patients) and appetite loss (16.0 %, 4/25 patients).

CONCLUSIONS

GEMOX combined with sorafenib as first-line therapy followed by sorafenib as maintenance therapy was effective with manageable toxicity for patients with advanced hepatocellular carcinoma. However, the results should be further validated in controlled phase II trials.

Antitumor effect of D-erythrose in an abdominal metastatic model of colon carcinoma

Traditional chemotherapy drugs against colorectal cancer possess little or no specificity, leading to severe intolerable side-effects. Therefore, it is necessary to develop additional specific therapeutic strategies. It has been suggested that D-erythrose may specifically inhibit the growth of tumor cells. However, the in vivo antitumor effect of D-erythrose against colorectal cancer remains unknown. Thus, the present study investigated the antitumor effect of D-erythrose in an abdominal metastatic model of colon carcinoma. Intraperitoneal (IP) colon carcinoma-bearing BALB/c mice received an IP injection of D-erythrose or normal saline (NS) daily for 15 days. The mice were weighed every three days. The tumor weights and the volume of ascites were evaluated following the treatment. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was used to assess apoptosis in tumor tissues. The results revealed that D-erythrose significantly reduced the weight of the intraperitoneal tumor by 69.1%, markedly inhibited the development of ascites and increased tumor cell apoptosis, without any observed toxic effects. These observations suggest that D-erythrose possesses antitumor activity against colon cancer. The present study may provide a potentially effective and specific approach for colon cancer treatment.

Nanoparticle delivery of photosensitive Pt(IV) drugs for circumventing cisplatin cellular pathway and on-demand drug release

A photosensitive platinum(IV) prodrug (UVA-Pt2) was attached to a biodegradable polymer (PE, methoxyl-poly(ethylene glycol)-block-poly(lactide-co-2-methyl-2-carboxyl-propylene carbonate-ethanol amine)) and then the conjugate was self-assembled to micelles (NP-UVA-Pt2). In vitro MTT assay of NP-UVA-Pt2 demonstrated an improved cytotoxicity against SKOV-3 cells than that of cisplatin. Confocal laser scanning microscopy (CLSM) indicated that NP-UVA-Pt2 were endocytosed rather than internalized by passive diffusion, and thus, this process has nothing to do with copper transporter protein (Ctr1) as reported for cisplatin, which is closely related to drug resistance of Pt based drugs. Intracellular platinum content measured by ICP-MS result suggested that NP-UVA-Pt2 expressed higher platinum intracellular uptake than cisplatin. NP-UVA-Pt2 demonstrated fast and robust response to photo irradiation while the nanoparticles were stable in PBS at PH7.4 in the dark. The great drug efficacy of NP-UVA-Pt2 under UVA irradiation and the ineffectiveness in the dark makes NP-UVA-Pt2 an ideal light responsive on-demand drug delivery system. Hence, NP-UVA-Pt2 will be a promising platinum based drug in the near future.

Late effects of oxaliplatin-induced peripheral neuropathy (LEON)--cross-sectional cohort study of patients with colorectal cancer surviving at least 2 years

OBJECTIVES

Oxaliplatin accumulates in dorsal root ganglia, causing an axonal neuronopathy. Symptoms include numbness, pain and gait disturbance which may persist and impact on quality of life (QOL). Despite widespread use of this drug, its late effects and patient satisfaction outcomes have not been widely reported. Furthermore, there has been limited qualitative research published in this area. The objectives of this study were to establish the incidence and clinical impact of chronic peripheral neuropathy.

METHODS

We conducted a cross-sectional observational study of patients who started oxaliplatin treatment at least 2 years prior to study commencement. Patients were assessed in three ways: clinical assessment encompassing neurological examination and nerve conduction studies to calculate a total neuropathy score (TNS); self-reported assessment via validated questionnaires; and assessment by recorded interview. The clinical and questionnaire-based assessments were analysed quantitatively and the interview data used for qualitative assessment.

RESULTS

Twenty-five patients consented to participate. The mean starting dose of oxaliplatin given was 92 mg/m(2). The cumulative dose received ranged from 375 to 2,400 mg, with a mean cumulative dose of 1,515 mg. Oxaliplatin was ceased due to neuropathy in six patients (24 %), after a mean of 9 cycles of treatment. Modified TNS ranged from 1 to 15 with a mean of 9.5. There was a statistically significant correlation between cumulative oxaliplatin dose and TNS. Quality of life and functional impact questionnaires showed mildly lower physical quality of life, higher pain scores and functional impairment secondary to sensory deficit. Qualitative analysis demonstrated variable bio-psycho-social effects of chronic neuropathy but, importantly, highlighted that many patients felt they had been insufficiently warned of the risk of neuropathy. Despite this, the majority was satisfied with their decision to receive the drug.

CONCLUSION

Many patients objectively demonstrated mild to moderate oxaliplatin neuropathy >2 years post-treatment. The majority of patients did not recall being warned of the risks of chronic peripheral neuropathy. Many of those who recall being warned did not feel sufficient emphasis was placed on the issue. Despite a varying burden of neuropathic symptoms, the majority of patients were highly satisfied with their decision to receive oxaliplatin.

Idiopathic intracranial hypertension and oxaliplatin: a causal association?

We report a case of a 54-year-old woman presented at the emergency service with complaints of transitory visual obscurations for four days, and headache, nausea and occasional vomiting in the last two months. She had been diagnosed of colorectal cancer one year ago and she was on treatment with oxaliplatin on a FOLFOX schedule. On ophthalmic examination, the vision was of 20/20 in both eyes and bilateral disc swelling was noted. The neurologic examination was normal. Magnetic resonance revealed no changes. A diagnostic lumbar puncture demonstrated an elevated opening pressure of 290 mm H2O with normal compounds. Due to the suspicion of ocular toxicity, oxaliplatin treatment was stopped. Treatment with oral acetazolamide was started and maintained for one month. In three weeks ocular and systemic symptoms totally disappeared and disc swelling gradually improved in the following months. Ocular toxicity has been reported as an infrequent adverse effect of oxaliplatin, but intracranial idiopathic pressure has not yet been described. Findings in this case suggest that oxaliplatin could be the cause for these symptoms. As the use of oxaliplatin is increasing as first-line treatment in colorectal cancer, we have to be alert to its potential toxicity.

A descriptive study of persistent oxaliplatin-induced peripheral neuropathy in patients with colorectal cancer

BACKGROUND

Prolonged neurotoxicity after systemic chemotherapy has the potential to impact on quality of life. We explored the frequency of persistent peripheral neuropathy in patients who received oxaliplatin for colorectal cancer at two local centres.

PATIENTS AND METHODS

Questionnaires were sent to patients who completed treatment with oxaliplatin for colorectal cancer at least 20 months prior to entering the study. Neuropathy questions were adapted from the FACT/GOG-Ntx (V.4) questionnaire.

RESULTS

Of the 56 eligible patients, 27 returned the questionnaire. Twenty-five patients (93 %) experienced neuropathic symptoms during their treatment; 11 had grade-2, and two had grade-3 symptoms. At the time of completing the questionnaire, 17 patients (63.0 %; 95%CI 43.9-79.4 %) were still symptomatic with 12 patients (44.4 %; 95%CI 26.8-63.3) having grade-2 or grade-3 symptoms and three patients (11.1 %; 95%CI 2.9-27.3) having grade-3 neuropathic symptoms. Participants who received more than 900 mg/m2 oxaliplatin had a significantly higher risk of persistent grade-2 or grade-3 neuropathy (p = 0.031, RR = 8.3 95%CI = 1.2-57.4). There was a trend toward increased risk of persistent neuropathy of any grade among participants with a history of regular alcohol use (p = 0.051; RR = 1.7 95%CI 1.0-2.8).

CONCLUSION

Persistent oxaliplatin-induced neuropathy is not as uncommon as previously suggested, and the rate of grade-2 and grade-3 symptoms could be considerably higher than previous reports.

Nurse self-evaluation of assessment of chemotherapy-induced peripheral neuropathy in patients with cancer

The focus of this study was to assess the feasibility and clinical implementation of a standardized assessment for chemotherapy-induced peripheral neuropathy (CIPN) by registered nurses in patients undergoing neurotoxic chemotherapy. A total of 24 registered nurses from 4 different institutions were enrolled into the study. A pre- and posttest design was used to assess changes in nurses’ attitudes, knowledge, and perceived skill in CIPN assessment. Using selected data collection instruments, nurses performed standardized assessments during the course of chemotherapy treatments. Patient-reported symptoms, vibratory sensation, deep-tendon reflexes, and touch were collected at three time points during chemotherapy treatment. Results indicated there was no statistically significant change in knowledge of chemotherapy-induced peripheral neuropathy from baseline to the end of the study. However, this finding may be due to poor internal consistency noted among the items of the Nurse Knowledge and Attitudes CIPN Assessment. Implementation of a standardized subjective and objective nursing assessment of CIPN was feasible with a total mean feasibility score of 3.76 (range 0–5) with each individual item scoring between 3.35 and 3.91. The intervention did improve pretest and posttest confidence in performing assessment for CIPN (p = .003).

Interventions for preventing neuropathy caused by cisplatin and related compounds

BACKGROUND

Cisplatin and several related antineoplastic drugs used to treat many types of solid tumours are neurotoxic, and most patients completing a full course of cisplatin chemotherapy develop a clinically detectable sensory neuropathy. Effective neuroprotective therapies have been sought.

OBJECTIVES

To examine the efficacy and safety of purported chemoprotective agents to prevent or limit the neurotoxicity of cisplatin and related drugs.

SEARCH METHODS

On 4 March 2013, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, and CINAHL Plus for randomised trials designed to evaluate neuroprotective agents used to prevent or limit neurotoxicity of cisplatin and related drugs among human patients.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs in which the participants received chemotherapy with cisplatin or related compounds, with a potential chemoprotectant (acetylcysteine, amifostine, adrenocorticotrophic hormone (ACTH), BNP7787, calcium and magnesium (Ca/Mg), diethyldithiocarbamate (DDTC), glutathione, Org 2766, oxcarbazepine, or vitamin E) compared to placebo, no treatment, or other treatments. We considered trials in which participants underwent evaluation zero to six months after completing chemotherapy using quantitative sensory testing (the primary outcome) or other measures including nerve conduction studies or neurological impairment rating using validated scales (secondary outcomes).

DATA COLLECTION AND ANALYSIS

Two review authors assessed each study, extracted the data and reached consensus, according to standard Cochrane methodology.

MAIN RESULTS

As of 2013, the review includes 29 studies describing nine possible chemoprotective agents, as well as description of two published meta-analyses. Among these trials, there were sufficient data in some instances to combine the results from different studies, most often using data from secondary non-quantitative measures. Nine of the studies were newly included at this update. Few of the included studies were at a high risk of bias overall, although often there was too little information to make an assessment. At least two review authors performed a formal review of an additional 44 articles but we did not include them in the final review for a variety of reasons.Of seven eligible amifostine trials (743 participants in total), one used quantitative sensory testing (vibration perception threshold) and demonstrated a favourable outcome in terms of amifostine neuroprotection, but the vibration perception threshold result was based on data from only 14 participants receiving amifostine who completed the post-treatment evaluation and should be regarded with caution. Furthermore the change measured was subclinical. None of the three eligible Ca/Mg trials (or four trials if a single retrospective study was included) described our primary outcome measures. The four Ca/Mg trials included a total of 886 participants. Of the seven eligible glutathione trials (387 participants), one used quantitative sensory testing but reported only qualitative analyses. Four eligible Org 2766 trials (311 participants) employed quantitative sensory testing but reported disparate results; meta-analyses of three of these trials using comparable measures showed no significant vibration perception threshold neuroprotection. The remaining trial reported only descriptive analyses. Similarly, none of the three eligible vitamin E trials (246 participants) reported quantitative sensory testing. The eligible single trials involving acetylcysteine (14 participants), diethyldithiocarbamate (195 participants), oxcarbazepine (32 participants), and retinoic acid (92 participants) did not perform quantitative sensory testing. In all, this review includes data from 2906 participants. However, only seven trials reported data for the primary outcome measure of this review, (quantitative sensory testing) and only nine trials reported our objective secondary measure, nerve conduction test results. Additionally, methodological heterogeneity precluded pooling of the results in most cases. Nonetheless, a larger number of trials reported the results of secondary (non-quantitative and subjective) measures such as the National Cancer Institute Common Toxicity Criteria (NCI-CTC) for neuropathy (15 trials), and these results we pooled and reported as meta-analysis. Amifostine showed a significantly reduced risk of developing neurotoxicity NCI-CTC (or equivalent) ≥ 2 compared to placebo (RR 0.26, 95% CI 0.11 to 0.61). Glutathione was also efficacious with an RR of 0.29 (95% CI 0.10 to 0.85). In three vitamin E studies subjective measures not suitable for combination in meta analysis each favoured vitamin E. For other interventions the qualitative toxicity measures were either negative (N-acetyl cysteine, Ca/Mg, DDTC and retinoic acid) or not evaluated (oxcarbazepine and Org 2766).Adverse events were infrequent or not reported for most interventions. Amifostine was associated with transient hypotension in 8% to 62% of participants, retinoic acid with hypocalcaemia in 11%, and approximately 20% of participantss withdrew from treatment with DDTC because of toxicity.

AUTHORS' CONCLUSIONS

At present, the data are insufficient to conclude that any of the purported chemoprotective agents (acetylcysteine, amifostine, calcium and magnesium, diethyldithiocarbamate, glutathione, Org 2766, oxcarbazepine, retinoic acid, or vitamin E) prevent or limit the neurotoxicity of platin drugs among human patients, as determined using quantitative, objective measures of neuropathy. Amifostine, calcium and magnesium, glutathione, and vitamin E showed modest but promising (borderline statistically significant) results favouring their ability to reduce the neurotoxicity of cisplatin and related chemotherapies, as measured using secondary, non-quantitative and subjective measures such as the NCI-CTC neuropathy grading scale. Among these interventions, the efficacy of only vitamin E was evaluated using quantitative nerve conduction studies; the results were negative and did not support the positive findings based on the qualitative measures. In summary, the present studies are limited by the small number of participants receiving any particular agent, a lack of objective measures of neuropathy, and differing results among similar trials, which make it impossible to conclude that any of the neuroprotective agents tested prevent or limit the neurotoxicity of platinum drugs.

Chemotherapy-induced peripheral neuropathy in adults: a comprehensive update of the literature

Commonly used chemotherapeutic agents in oncology/hematology practice, causing toxic peripheral neuropathy, include taxanes, platinum compounds, vinca alkaloids, proteasome inhibitors, and antiangiogenic/immunomodulatory agents. This review paper intends to put together and discuss the spectrum of chemotherapy-induced peripheral neuropathy (CIPN) characteristics so as to highlight areas of future research to pursue on the topic. Current knowledge shows that the pathogenesis of CIPN still remains elusive, mostly because there are several sites of involvement in the peripheral nervous system. In any case, it is acknowledged that the dorsal root ganglia of the primary sensory neurons are the most common neural targets of CIPN. Both the incidence and severity of CIPN are clinically under- and misreported, and it has been demonstrated that scoring CIPN with common toxicity scales is associated with significant inter-observer variability. Only a proportion of chemotherapy-treated patients develop treatment-emergent and persistent CIPN, and to date it has been impossible to predict high-and low-risk subjects even within groups who receive the same drug regimen. This issue has recently been investigated in the context of pharmacogenetic analyses, but these studies have not implemented a proper methodological approach and their results are inconsistent and not really clinically relevant. As such, a stringent approach has to be implemented to validate that information. Another open issue is that, at present, there is insufficient evidence to support the use of any of the already tested chemoprotective agents to prevent or limit CIPN. The results of comprehensive interventions, including clinical, neurophysiological, and pharmacogenetic approaches, are expected to produce a consistent advantage for both doctors and patients and thus allow the registration and analysis of reliable data on the true characteristics of CIPN, eventually leading to potential preventive and therapeutic interventions.

Improved time to treatment failure with an intermittent oxaliplatin strategy: results of CONcePT

BACKGROUND

Oxaliplatin is an integral component of colorectal cancer treatment, but its use is limited by neurotoxicity. The Combined Oxaliplatin Neurotoxicity Prevention Trial (CONcePT) tested intermittent oxaliplatin (IO) administration and the use of concurrent calcium and magnesium salts (Ca/Mg), two modifications intended to reduce neurotoxicity and extend the duration of treatment.

PATIENTS AND METHODS

In this trial involving double randomization, 140 patients were randomized to receive modified FOLFOX7 plus bevacizumab with IO (eight-cycle blocks of oxaliplatin treatment) versus continuous oxaliplatin (CO); and Ca/Mg versus placebo (pre- and postoxaliplatin infusion). The primary end point was time-to-treatment failure (TTF).

RESULTS

One hundred thirty-nine patients were entered and treated up to the point of early study termination due to concerns by the data-monitoring committee (DMC) that Ca/Mg adversely affected tumor response. Tumor response was not a study end point. Given DMC concerns, an additional independent, blinded radiology review of all images showed no adverse effect of treatment schedule or Ca/Mg on response by Response Evaluation Criteria In Solid Tumors. The IO schedule was superior to CO [hazard ratio (HR) = 0.581, P = 0.0026] for both TTF and time-to-tumor progression (TTP) (HR = 0.533, P = 0.047).

CONCLUSIONS

An IO dosing schedule had a significant benefit on both TTF and TTP versus CO dosing in this trial despite the very attenuated sample. There was no effect of Ca/Mg on response.

Oxaliplatin-induced neuropathy in colorectal cancer: many questions with few answers

Oxaliplatin is a chemotherapeutic agent effective against advanced colorectal cancer. Unlike with other platinum-based agents, the main side effect of oxaliplatin is polyneuropathy. Oxaliplatin-induced polyneuropathy (OIPN) has a unique profile, which can be divided into acute and chronic neurotoxicity. Early identification of the neurotoxicity and alterations in dose or schedule for the medication could prevent the development of chronic symptoms, which, once established, may take many months or years to resolve or even persist throughout life with a substantial effect on quality of life. There is no doubt that the use of pharmacogenomic methods to identify genetic bases of interindividual differences in drug response has led to what is called tailoring treatment. Yet there are some challenges regarding the application of these differences. Many efforts have been made to prevent or treat OIPN. Better understanding of the mechanisms underlying the acute and chronic forms of OIPN will be a key component of future advances in the prevention and treatment of OIPN. The aim of this review is to highlight the clinical presentation, assessment, and management of OIPN, as well as the underlying pathophysiologic and pharmacogenomic background.

A TRPA1 antagonist reverts oxaliplatin-induced neuropathic pain

Neuropathic pain (NeP) is generally considered an intractable problem, which becomes compelling in clinical practice when caused by highly effective chemotherapeutics, such as in the treatment of cancer with oxaliplatin (OXA) and related drugs. In the present work we describe a structurally new compound, ADM_09, which proved to effectively revert OXA-induced NeP in vivo in rats without eliciting the commonly observed negative side-effects. ADM_09 does not modify normal behavior in rats, does not show any toxicity toward astrocyte cell cultures, nor any significant cardiotoxicity. Patch-clamp recordings demonstrated that ADM_09 is an effective antagonist of the nociceptive sensor channel TRPA1, which persistently blocks mouse as well as human variants of TRPA1. A dual-binding mode of action has been proposed for ADM_09, in which a synergic combination of calcium-mediated binding of the carnosine residue and disulphide-bridge-forming of the lipoic acid residue accounts for the observed persistent blocking activity toward the TRPA1 channel.

Predicting acute and persistent neuropathy associated with oxaliplatin

OBJECTIVES

We sought to predict oxaliplatin-associated peripheral neuropathy during modified FOLFOX6 (mFOLFOX6) therapy.

METHODS

Equal numbers of male and female patients with previously untreated, primary or recurrent colorectal cancer were followed through a first course of mFOLFOX6 with 85 mg/m² oxaliplatin every 2 weeks. Accounting for correlation among a subject's cycle, logistic regression estimated per cycle risk of acute (under 14 d) and persistent (14 d or more) neuropathy. Proportional hazards regression predicted time to persistent neuropathy.

RESULTS

Among mFOLFOX6 recipients (n = 50, age 58.9 ± 10.1 y), 36% received concomitant bevacizumab. Of the total number of cycles, 94.2% (422/448) were evaluable. Most (84%) subjects reported neuropathy at least once; 74% reported acute and 48% reported persistent symptoms. On multivariate analysis, risk factors shared by acute and persistent neuropathy were body surface area >2.0, acute neuropathy in a past cycle, and lower body weight. In addition, risk of acute neuropathy decreased with age (adjusted for renal function and winter season), whereas risk of persistent neuropathy increased with cumulative dose of oxaliplatin and persistent neuropathy in a past cycle. Concomitant bevacizumab was not a risk factor when administered in stage IV disease but was associated with persistent neuropathy when administered experimentally in stage III. Females had no increased risk of either form of neuropathy. After 3 cycles, weight, body surface area, and prior acute neuropathy predicted time to persistent neuropathy.

CONCLUSIONS

Routinely available clinical factors predict acute and persistent neuropathy associated with oxaliplatin. When validated, the proposed prognostic score for persistent neuropathy can help clinicians counsel patients about chemotherapy.

The effect of curcumin on oxaliplatin and cisplatin neurotoxicity in rats: some behavioral, biochemical, and histopathological studies

Cisplatin is commonly used against several solid tumors, and oxaliplatin is an effective cytotoxic drug used in colorectal cancer. A major clinical issue affecting 10-40 % of patients treated with cisplatin or oxaliplatin is severe peripheral neuropathy causing sensory, motor, and autonomic dysfunction, with symptoms including cold sensitivity and neuropathic pain. The biochemical basis of the neurotoxicity is uncertain, but is associated with oxidative stress. Curcumin (a natural phenolic yellow pigment) has strong antioxidant, anticancer, and anti-inflammatory actions. Here we report the possible protective effect of curcumin on some cisplatin- and oxaliplatin-induced behavioral, biochemical, and histopathological alterations in rats. Twenty-four hours after the end of treatments some motor and behavioral tests (motor activity, thermal and mechanical nociception, and neuromuscular coordination) were conducted, followed by measuring plasma neurotensin platinum concentration in the sciatic nerve, and studying the histopathology of the sciatic nerve. Oxaliplatin (4 mg/kg) and cisplatin (2 mg/kg) [each given twice weekly, in a total of nine intraperitoneal injections over 4.5 weeks] significantly increased plasma neurotensin concentration, caused specific damage in the histology of the sciatic nerve and produced variable effects in the motor and behavioral tests. Oral curcumin (10 mg/kg, 4 days before the platinum drug, and thereafter, concomitantly with it for 4.5 weeks) reversed the alterations in the plasma neurotensin and sciatic nerve platinum concentrations, and markedly improved sciatic nerve histology in the platinum-treated rats. Larger experiments using a wider dose range of oxaliplatin, cisplatin, and curcumin are required to fully elucidate the possible protective role of curcumin in platinum-induced neurotoxicity.

Can medical herbs stimulate regeneration or neuroprotection and treat neuropathic pain in chemotherapy-induced peripheral neuropathy?

Chemotherapy-induced neuropathy (CIPN) has a relevant impact on the quality of life of cancer patients. There are no curative conventional treatments, so further options have to be investigated. We conducted a systematic review in English and Chinese language databases to illuminate the role of medical herbs. 26 relevant studies on 5 single herbs, one extract, one receptor-agonist, and 8 combinations of herbs were identified focusing on the single herbs Acorus calamus rhizoma, Cannabis sativa fructus, Chamomilla matricaria, Ginkgo biloba, Salvia officinalis, Sweet bee venom, Fritillaria cirrhosae bulbus, and the herbal combinations Bu Yang Huan Wu, modified Bu Yang Huan Wu plus Liuwei Di Huang, modified Chai Hu Long Gu Mu Li Wan, Geranii herba plus Aconiti lateralis praeparata radix , Niu Che Sen Qi Wan (Goshajinkigan), Gui Zhi Jia Shu Fu Tang (Keishikajutsubuto), Huang Qi Wu Wu Tang (Ogikeishigomotsuto), and Shao Yao Gan Cao Tang (Shakuyakukanzoto). The knowledge of mechanism of action is still limited, the quality of clinical trials needs further improvement, and studies have not yielded enough evidence to establish a standard practice, but a lot of promising substances have been identified. While CIPN has multiple mechanisms of neuronal degeneration, a combination of herbs or substances might deal with multiple targets for the aim of neuroprotection or neuroregeneration in CIPN.

Safety and efficacy of calcium and magnesium infusions in the chemoprevention of oxaliplatin-induced sensory neuropathy in gastrointestinal cancers

OBJECTIVE

To derive a more precise estimation on the safety and efficacy of calcium and magnesium (Ca and Mg) infusions in the prevention of oxaliplatin-induced sensory neuropathy.

METHODS

A total of 16 studies including 1765 individuals were involved in this meta-analysis. Odds ratio (OR) and its 95% confidence interval (CI) were calculated.

RESULTS

The difference in the incidence of oxaliplatin-induced neuropathy grade ≥ 1 was statistically significant between the Ca and Mg infusions treatment group and the untreated group (National Cancer Institute common toxicity criteria [NCI CTC]: OR 0.44, 95% CI 0.31-0.62, P = 0.000; oxaliplatin-specific scale [OSS]: OR 0.30, 95% CI 0.20-0.45, P = 0.000). Similar results were found in the incidences of oxaliplatin-induced neuropathy grade ≥ 2 (NCI CTC: OR 0.60, 95% CI 0.46-0.77, P = 0.000; OSS: OR 0.45, 95% CI 0.30-0.67, P = 0.000). However, we did not detect a trend of fewer oxaliplatin-induced neuropathy grade ≥ 3 incidences in the Ca and Mg infusions treatment group than the untreated group (NCI CTC: OR 0.67, 95% CI 0.44-1.01, P = 0.054; OSS: OR 0.66, 95% CI 0.34-1.29, P = 0.224). There was no difference in the response rate between the Ca and Mg treated group and the untreated group (OR 0.89, 95% CI 0.67-1.17, P = 0.391).

CONCLUSION

Ca and Mg infusions do not alter the efficacy of oxaliplatin-based chemotherapy in gastrointestinal cancers, which may be reasonable to add them to lessen the incidence of neuropathy.

Association between GSTP1 Ile105Val polymorphism and oxaliplatin-induced neuropathy: a systematic review and meta-analysis

BACKGROUND AND AIMS

The association between glutathione-S-transferase P1 (GSTP1) Ile105Val polymorphism and oxaliplatin-induced neuropathy has been investigated in a number of published studies. However, most of these studies were based on small sample sizes and the results remained inconsistent. To assess the relationship between GSTP1 gene Ile105Val polymorphism and its susceptibility to oxaliplatin-induced neuropathy, a meta-analysis of previous studies was conducted.

METHODS

Two investigators independently searched studies published up to December 2012 from the databases of PubMed, EMBASE and The Cochrane Library. The pooled effect was calculated as odds ratio (OR) and corresponding 95 % confidence intervals (CIs) using fixed-effect or random-effect model.

RESULTS

Twelve prospective trials and two retrospective clinical trials involving 2,191 participants met the inclusion criteria. Combined analyses of these studies showed no significant associations between GSTP1 Ile105Val polymorphism and oxaliplatin-induced neuropathy, yielding OR of 1.08 (95 %CI 0.67-1.74, P = 0.754) in dominant model. Similar results were also obtained in recessive model (OR = 1.67, 95 %CI 0.56-4.93, P = 0.357) and allelic analysis (OR = 1.22, 95 %CI 0.67-2.24, P = 0.513). Since significant heterogeneity across studies, the pooled effects were calculated by random-effect model. No evidence of publication biases was identified in this meta-analysis.

CONCLUSION

This meta-analysis did not support the hypothesis that GSTP1 Ile105Val polymorphism was related to the occurrence of neurotoxicity in oxaliplatin-treated patients. Given the limited number of studies and potential bias, large-scale and well-designed clinical trials should be needed to confirm these hypotheses.

Vitamin E for prevention of oxaliplatin-induced peripheral neuropathy: a pilot randomized clinical trial

CONTEXT AND OBJECTIVE Oxaliplatin is one of the chemotherapy regimens most used for treating colorectal cancer. One of the main limitations to its use is induction of peripheral neuropathy. Previous studies have shown that vitamin E can reduce the incidence of peripheral neuropathy by 50%. This study aimed to assess the effectiveness of vitamin E for prevention of oxaliplatin-induced peripheral neuropathy. DESIGN AND SETTING Prospective, phase II, randomized pilot study developed at a university hospital in the Greater ABC region. METHODS Patients were randomized five days before starting oxaliplatin treatment, to receive either vitamin E or placebo until the end of the chemotherapy regimen. The outcome was evaluated using the Common Terminology Criteria for Adverse Events (CTCAE), version 3, and specific gradation scales for oxaliplatin-induced peripheral neuropathy. Patients with colorectal and gastric cancer who had been scheduled to receive oxaliplatin-based chemotherapy were included. Both groups received calcium and magnesium supplementation before and after oxaliplatin infusions. RESULTS Eighteen patients were randomized to the vitamin E group and 16 to the placebo group. Cumulative incidence of 83% with peripheral neuropathy grades 1/2 was observed in the vitamin E group, versus 68% in the placebo group (P = 0.45). A trend towards more diarrhea was observed among patients who received vitamin E (55.6% vs. 18.8%; P = 0.06). There were no other significant differences in toxicity between the groups. CONCLUSIONS No significant decrease in the incidence of acute oxaliplatin-induced peripheral neuropathy was demonstrated through vitamin E use.

Membrane transporters as mediators of Cisplatin effects and side effects

Transporters are important mediators of specific cellular uptake and thus, not only for effects, but also for side effects, metabolism, and excretion of many drugs such as cisplatin. Cisplatin is a potent cytostatic drug, whose use is limited by its severe acute and chronic nephro-, oto-, and peripheral neurotoxicity. For this reason, other platinum derivatives, such as carboplatin and oxaliplatin, with less toxicity but still with antitumoral action have been developed. Several transporters, which are expressed on the cell membranes, have been associated with cisplatin transport across the plasma membrane and across the cell: the copper transporter 1 (Ctr1), the copper transporter 2 (Ctr2), the P-type copper-transporting ATPases ATP7A and ATP7B, the organic cation transporter 2 (OCT2), and the multidrug extrusion transporter 1 (MATE1). Some of these transporters are also able to accept other platinum derivatives as substrate. Since membrane transporters display a specific tissue distribution, they can be important molecules that mediate the entry of platinum derivatives in target and also nontarget cells possibly mediating specific effects and side effects of the chemotherapeutic drug. This paper summarizes the literature on toxicities of cisplatin compared to that of carboplatin and oxaliplatin and the interaction of these platinum derivatives with membrane transporters.

Calcium channel blockers reduce oxaliplatin-induced acute neuropathy: a retrospective study of 69 male patients receiving modified FOLFOX6 therapy

Oxaliplatin-based chemotherapy has been widely used for colorectal cancer. However, it causes severe acute and chronic peripheral neuropathies. Recently, we reported that calcium channel blockers prevent the oxaliplatin-induced cold hyperalgesia in rats. The purpose of this study was to determine whether the treatment with calcium channel blockers prevents the peripheral neuropathy during oxaliplatin therapy. The electronic medical charts for patients who received modified FOLFOX6 regimen from January 2008 to December 2010 were evaluated. Of the 200 patients who received modified FOLFOX6 therapy, 84 patients were excluded due to the exclusion criteria. Calcium channel blockers had been taken by 26 of 69 male patients, but only three of 47 female patients. Therefore, in the present analysis, the male data of the groups with and without calcium channel blockers (n=26 and 43, respectively) were compared. The cumulative incidence curve of acute neuropathy was significantly lower in the group with calcium channel blockers (P=0.0438, log-rank test), whereas there was no difference between these groups in the cumulative incidence curve of chronic neuropathy (P=0.4919, log-rank test). The present study indicated that calcium channel blockers inhibit the development of acute peripheral neuropathy in patients receiving modified FOLFOX6 therapy.

Effect of green tea extracts on oxaliplatin-induced peripheral neuropathy in rats

BACKGROUND

A common side effect of oxaliplatin is peripheral neurotoxicity. Oxidative stress to dorsal root ganglion (DRG) may be one of important pathogenic mechanisms. Green tea contains four polyphenol catechins, which are known to be potent antioxidants. The present work is aimed to determine whether green tea extracts have neuroproective or palliative effects on neurotoxicity symptoms induced by oxaliplatin.

METHODS

We conducted behavioral tests including sensory and thermal thresholds, an electrophysiological study, and TUNEL staining to assess neurotoxicity during the experimental period using animal models.

RESULTS

A total of 14 adult rats were randomly allocated into two groups. Oxaliplatin (4 mg/kg) with or without green tea (300 mg/kg orally once daily) was administered intraperitoneally twice per week for 6 weeks. At 4 and 6 weeks after oxaliplatin administration, sensory threshold values were significantly decreased and at 6 weeks after oxaliplatin administration, thermal threshold values were significantly increased in oxaliplatin-treated rats compared with those in rat treated with oxaliplatin and green tea extracts. The electrophysiological assessment, including sensory nerve conduction and H-reflex-related sensory nerve conduction velocity, revealed no significant changes in the two groups. TUNEL staining showed no significant difference in the number of apoptotic-featured cells between the two experimental groups in the DRG or peripheral nerves, but the number of apoptotic-featured cells in DRG was higher than that in sciatic nerves within each group.

CONCLUSIONS

Green tea extracts may be a useful adjuvant to alleviate sensory symptoms after oxaliplatin administration, such as allodynia, but did not prevent morphometric or electrophysiological alterations induced by oxaliplatin.

Co-delivery of daunomycin and oxaliplatin by biodegradable polymers for safer and more efficacious combination therapy

An oxaliplatin pro-drug (Oxa(IV)-COOH) with an axial carboxyl group was synthesized and conjugated to biodegradable polymers with pendant hydroxyl groups to prepare polymer-Oxa(IV) conjugates. A hydrophobic anthracycline-based drug, daunorubicin (DRB) was conjugated to similar biodegradable polymers with carboxyl groups to synthesize polymer-DRB conjugates. The two drug conjugates have the similar polymer backbone and are amphiphilic; thus, they can co-assemble into composite micelles. In the composite micelles, the polymer-Oxa(IV) conjugates can release clinically widely used water soluble anticancer drug oxaliplatin (Oxa(II)) upon reduction, while polymer-DRB conjugate is thought to release DRB via acid hydrolysis in the cancer cells. In this way, combination of the hydrophilic platinum drug Oxa(II) and hydrophobic drug DRB can be realized by delivering them in one platform. Moreover, the composite micelles showed reduced systematic toxicity and greater synergistic effect than combination of small molecules of the two anticancer drugs both in vitro and in vivo; thus, this polymer based combination therapy can be useful in future clinic application.

Oxaliplatin-induced neuropathy in colorectal cancer

Oxaliplatin use in palliative and adjuvant treatment of colon cancer is frequently limited by cumulative neurotoxicity, leading to reduced quality of life and decreased dose. The mechanism of this neurotoxicity is unclear, but may relate to neuronal voltage-gated sodium channels involving calcium chelation by a metabolite of the drug. Various preventative measures have been tested to reduce the incidence of neurotoxicity, including calcium and magnesium infusions, dose interruption of the drug, and prophylactic neuromodulatory agents. Despite the promising efficacy of these measures, they are not universally accepted. Less is known about the best way to treat established neurotoxicity, which is permanent in some patients, although venlafaxine has shown promise in small clinical trials. This paper analyzes the extent, cause and risk factors for neuropathy, and the potential preventative and therapeutic treatments for oxaliplatin-induced neuropathy.

Assessing the impact of chemotherapy-induced peripheral neurotoxicity on the quality of life of cancer patients: the introduction of a new measure

Purpose

To investigate the impact of chemotherapy-induced neurotoxicity on daily activities and quality of life (QoL) of cancer patients.

Methods

QoL of all patients visiting the oncological outpatient ward of the Maxima Medical Centre in the Netherlands from October 2006 until March 2007 treated with taxanes, vinca-alkaloids and/or platinum compounds (n = 88) was compared with the QoL of patients that did not receive these treatments yet (n = 43). Patient-reported neuropathy symptoms were evaluated with the newly developed Chemotherapy Induced Neurotoxicity Questionnaire (CINQ) and the Functional Assessment of Cancer Therapy/Gynaecologic Oncology Group/Neurotoxicity (FACT/GOG-Ntx) questionnaire.

Results

Patients treated with chemotherapy reported significantly more complaints of neuropathy (p < 0.001) and more paresthesias and dysesthesias in the upper (p < 0.001; p < 0.01) and lower extremities (p < 0.001) compared to those not treated with chemotherapy. They additionally experienced problems with fine motor function (e.g., getting (un)dressed, writing, and picking up small objects). Moreover, cold-induced paresthesias were frequently reported. Overall, patients indicated that their neuropathy had a negative effect on QoL.

Conclusions

The newly developed CINQ and the FACT/GOG-Ntx results suggest a considerable negative impact of patient-reported neuropathy symptoms on daily activities and QoL in cancer patients treated with chemotherapy. However, further validation of the CINQ is needed.

Chemotherapy-induced peripheral neuropathy: a literature review

ABSTRACT Peripheral neuropathy is a common side effect in patients undergoing cancer treatment with chemotherapy. This condition can affect patients in several different ways, interfering in their activities of daily living and autonomy. The present study aimed to review the literature on chemotherapy-induced peripheral neuropathy and its treatment or other possible interventions. The findings reveal that chemotherapy-induced peripheral neuropathy is a common condition that affects patients undergoing treatment with some specific drugs. Besides, several different substances have been used to treat or control this condition, although no significant evidence could be found in these studies.

Polymorphic markers associated with severe oxaliplatin-induced, chronic peripheral neuropathy in colon cancer patients

BACKGROUND

To identify potential genetic markers for severe oxaliplatin-induced chronic peripheral neuropathy (OXCPN), the authors performed a genome-wide association analysis of patients with colon cancer who received oxaliplatin-based chemotherapy.

METHODS

This was a prospective study in which DNA was purified in peripheral blood from patients with colon cancer who received oxaliplatin. The primary endpoint was the development of severe (grade 2 lasting for >7 days or grade 3) OXCPN. For the discovery set, genotyping was done for 96 patients who received adjuvant fluorouracil and oxaliplatin using the a genome-wide human single-nucleotide polymorphism (SNP) array. An association between polymorphisms and severe OXCPN was investigated. At the same time, 247 patients who received oxaliplatin-based, first-line chemotherapy for advanced disease were enrolled as a validation set.

RESULTS

Among the 32 genotyped candidate SNPs selected from the discovery set, 9 SNPs in 8 genes (tachykinin, precursor 1[TAC1]; forkhead box C1 [FOXC1]; integrin, alpha 1 [ITGA1]; acylphosphatase 2, muscle type [ACYP2]; deleted in lymphocytic leukemia, 7 [DLEU7]; B-cell translocation gene 4 [BTG4]; calcium/calmodulin-dependent protein kinase II inhibitor 1 [CAMK2N1]; and phenylalanyl-tRNA synthase 2 [FARS2]) had nominal replication (P < .05). The most significant association was observed at reference SNP number (rs)10486003 in TAC1 (P = 4.84 × 10(-7)) in combined data from 2 sets. Five SNPs (rs10486003, rs2338, rs830884, rs843748, and rs797519) were significant in a multiple regression analysis (P < .05). Overall prediction accuracy calculated by the regression model was 72.8% (95% confidence interval, 65.8%-79.9%) in the model development and 75.9% (95% confidence interval, 66.9%-84.9%) in the model evaluation.

CONCLUSIONS

The current results indicated that a genome-wide pharmacogenomic approach is useful for identifying novel polymorphism predictors of severe OXCPN that may be used in personalized chemotherapy.

Discrepancy between the NCI-CTCAE and DEB-NTC scales in the evaluation of oxaliplatin-related neurotoxicity in patients with metastatic colorectal cancer

BACKGROUND

Several oxaliplatin-specific scales have been proposed in clinical practice to evaluate oxaliplatin-related neurotoxicity. We investigated whether there might be a discrepancy between the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) and the Neurotoxicity Criteria of Debiopharm (DEB-NTC), the commonly used oxaliplatin-specific scales, in the evaluation of peripheral neurotoxicity.

PATIENTS AND METHODS

The subjects were 42 patients with metastatic colorectal cancer who received more than 6 cycles of first-line therapy with modified FOLFOX6 and more than 6 cycles of second-line therapy with FOLFIRI. The median number and cumulative dose of oxaliplatin administrations were 10.5 (range 6-22) and 889.4 mg/m(2) (range 484.5-1875.0 mg/m(2)), respectively. The peripheral neurotoxicity was evaluated during mFOLFOX6 therapy and after its discontinuation using NCI-CTCAE ver. 3.0 and DEB-NTC. Data were collected prospectively and analyzed retrospectively.

RESULTS

The concordance rate of the peripheral neurotoxicity grade determined by these criteria was low: 48.8% during mFOLFOX6 and 47.3% after discontinuation of therapy. The cumulative dose of oxaliplatin-related peripheral neurotoxicity in 50% of the patients was lower when evaluated by DEB-NTC for both grades 1 (P = 0.09) and 2 (P < 0.001). The cumulative rate of improvement from grade 2 to 1 (P < 0.001) and from grade 2 to 0 (P < 0.05) after discontinuation of mFOLFOX6 therapy was higher when NCI-CTCAE was used for the evaluation.

CONCLUSION

We found a discrepancy between the NCI-CTCAE and DEB-NTC scales in the evaluation of oxaliplatin-related neurotoxicity and suggest that the concomitant use of NCI-CTCAE and DEB-NTC would be useful to maintain oxaliplatin-based chemotherapy at higher quality.

Breast and colorectal cancer survivors' knowledge about their diagnosis and treatment

INTRODUCTION

Aspects of a personal cancer history can have implications for future decisions regarding screening, diagnosis, and treatment. Clinicians must sometimes rely on patients' self-report of their medical history. This study assessed knowledge of details of cancer diagnosis and treatment among breast and colorectal cancer survivors.

METHODS

Written surveys were completed by 480 breast cancer survivors and 366 colorectal cancer survivors diagnosed between 1999 and 2008 at a large cancer center in the Minneapolis, MN, area (81% response rate). Responses were compared with cancer registry and medical records.

RESULTS

Forty percent of breast cancer survivors and 65% of colorectal cancer survivors were unable to identify their stage of disease. Seven percent of breast cancer survivors and 21% of colorectal cancer survivors in whom regional nodes were examined did not know whether they had positive nodes. Accuracy of knowledge of estrogen and progesterone status among breast cancer survivors was 58% and 39%, respectively. Of breast cancer survivors treated with doxorubicin, 43% correctly identified it as a drug they had received. Their accuracy of identification of receipt of tamoxifen or specific aromatase inhibitors was >90%. Of colorectal cancer survivors treated with oxaliplatin, 52% correctly identified it as a drug they had received. Accuracy on many items decreased with patient age.

CONCLUSIONS

This study identifies several gaps in adult cancer survivors' knowledge of details of their diagnosis and treatment that have implications for follow-up care.

IMPLICATIONS FOR CANCER SURVIVORS

Provision of written treatment summaries to cancer survivors could help them obtain appropriate patient-centered long-term follow-up care.

Neurotoxicity caused by the treatment with platinum analogues

Platinum agents (cisplatin, carboplatin, and oxaliplatin) are a class of chemotherapy agents that have a broad spectrum of activity against several solid tumors. Toxicity to the peripheral nervous system is the major dose-limiting toxicity of at least some of the platinum drugs of clinical interest. Among the platinum compounds in clinical use, cisplatin is the most neurotoxic, inducing mainly sensory neuropathy of the upper and lower extremities. Carboplatin is generally considered to be less neurotoxic than cisplatin, but it is associated with a higher risk of neurological dysfunction if administered at high dose or in combination with agents considered to be neurotoxic. Oxaliplatin induces two types of peripheral neuropathy, acute and chronic. The incidence of oxaliplatin-induced neuropathy is related to various risk factors such as treatment schedule, cumulative dose, and time of infusion. To date, several neuroprotective agents including thiol compounds, vitamin E, various anticonvulsants, calcium-magnesium infusions, and other nonpharmacological strategies have been tested for their ability to prevent platinum-induced neurotoxicity with controversial results. Further studies on the prevention and treatment of neurotoxicity of platinum analogues are warranted.

Phase II study of FOLFOX4 with "wait and go" strategy as first-line treatment for metastatic colorectal cancer

PURPOSE

To evaluate the efficacy and safety of FOLFOX4 using "wait and go" strategy in treating metastatic colorectal cancer.

METHODS

The conventional FOLFOX4 was repeated every 2 weeks. We waited until the recovery of symptoms from persistent neurotoxicity within an added period of 2 weeks, before performing the next cycle ("wait and go" strategy).

RESULTS

We enrolled 58 patients, in whom a total of 481 cycles were administered (median 8 per patient; range 1-16). Toxicity was evaluated in 58 patients and response in 55. The major toxic effect was grade 3/4 neutropenia (33%). Painful paresthesia or persistent functional impairment was observed in 4 patients (7%). The response rate was 40% (95% confidence interval; 27.1-52.9%). The median progression-free survival time was 10.2 months, the 1-year survival rate was 89%, and the median overall survival time was 27.6 months.

CONCLUSIONS

These findings indicate that this "wait and go" strategy reduces the frequency of persistent neuropathy while maintaining efficacy against metastatic colorectal cancer.