Background
Chemotherapy-induced peripheral neuropathy (CIPN) is the major treatment-limiting toxicity of many anticancer agents, including paclitaxel. CIPN affects up to 70% of paclitaxel-treated patients, and approximately 30% experience severe symptoms.1,2 CIPN can last for years after finishing chemotherapy,3,4 significantly diminishing patients’ long-term quality of life.5 Although duloxetine has proven to be effective for relieving CIPN pain, there are no established strategies to prevent or treat sensory or motor CIPN symptoms.6,7 Therefore, patients experiencing moderate or severe CIPN may require treatment alterations that reduce efficacy and survival.8,9
Prior research has identified nonmodifiable CIPN risk factors, such as age, race, and genetics, and potentially though not easily modifiable risk factors, such as diabetes, sedentary lifestyle, and high systemic paclitaxel exposure.10 Several retrospective studies suggested that patients with lower pretreatment vitamin D concentrations have higher CIPN risk11,12; however, this has yet to be validated in a well-conducted retrospective analysis of a prospective clinical trial, referred to as a prospective-retrospective study.13–15 Validation of vitamin D insufficiency as a CIPN risk factor is a critical first step toward developing interventional strategies to prevent CIPN, extend chemotherapy treatment, and improve clinical outcomes.
The objective of this study was to validate pretreatment vitamin D insufficiency as a risk factor for CIPN in patients with early-stage breast cancer receiving paclitaxel. We conducted a prospective-retrospective analysis using data and samples from the SWOG S0221 clinical trial (ClinicalTrials.gov identifier: NCT00070564). We also examined the incidence of CIPN and vitamin D insufficiency in Black patients to determine whether vitamin D insufficiency contributes to the racial disparity in CIPN risk. After validation in patients, we attempted to determine whether vitamin D deficiency causes mechanical sensitivity in mice and sensitizes mice to mechanical sensitivity caused by paclitaxel.
Methods
Study Patients and Clinical Data
This prospective-retrospective study was conducted using data and serum samples from SWOG S0221, a randomized phase III trial comparing 6 different dosing schedules of standard doxorubicin/cyclophosphamide-paclitaxel (AC-T) adjuvant chemotherapy in patients with early-stage breast cancer.16,17 In the initial protocol, patients were randomized in a 2 × 2 factorial design to AC once per week for 15 doses versus every 2 weeks (Q2W) for 6 doses, followed by paclitaxel 80 mg/m2 once per week for 12 doses versus 175 mg/m2 Q2W for 6 doses. A revised AC regimen (Q2W for 4 doses) was added later, bringing the total study arms to 6. Information on preexisting neuropathy was not collected or used as an exclusion criterion. Adverse events were evaluated every 4 weeks while the patient was receiving protocol therapy using the NCI Common Terminology Criteria for Adverse Events (CTCAE) version 3.0.18 The primary endpoint of this analysis was grade 3 or higher (grade ≥3) sensory CIPN that was possibly, probably, or definitely related to chemotherapy treatment.
Of the 2,849 eligible female participants receiving paclitaxel on the S0221 trial, 1,620 had at least 2 available serum samples and provided consent for further research. All these patients had received paclitaxel with the dose to body surface area within 5% of the target ratio of the assigned arm and continued paclitaxel for at least 45 days. A total of 1,191 (74%) were selected for this biomarker analysis due to budgetary limitations and power calculations, indicating that this sample size was sufficient. Patients were selected to maximize informativeness in this and future analyses. All patients who reported grade ≥3 sensory or motor CIPN (n=204) or completed the DELCaP substudy baseline questionnaires (additional n=572) were selected for vitamin D analysis. The DELCaP substudy collected additional patient-reported lifestyle information and treatment toxicity.17,19 The remaining patients (n=415) were selected randomly from the available remaining eligible patients (n=844) to achieve the target number (supplemental eFigure 1, available with this article at JNCCN.org). Demographics were compared between patients with and without grade ≥3 sensory CIPN using t tests for continuous variables and chi-square tests for categorical variables.
Pretreatment Vitamin D Measurement
Blood samples were collected from study participants at enrollment, and serum was stored at −80°C. At the time of assay, samples were randomized, and 25-hydroxy vitamin D2 and D3 were quantified in a blinded manner using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay by Heartland Assays, which has been validated for use with archived specimens.20–23 Vitamin D2 or D3 concentrations below the limit of quantification (1.5 ng/mL) were imputed with half the limit of quantification. One patient inadvertently had 2 samples analyzed, so the average of the 2 concentrations was used. The primary independent variable, vitamin D insufficiency, was defined as total vitamin D concentration (D2 + D3) ≤20 ng/mL.24
Regression Analysis Between CIPN and Vitamin D
The primary analysis was conducted following an a priori analysis plan agreed upon by the study team and the SWOG Statistical Data Management Center. The analysis plan specified patient inclusion and exclusion criteria, definitions of the primary independent (total vitamin D insufficiency) and dependent (grade ≥3 sensory CIPN) variables, covariates, statistical tests, and a 2-sided α level of .05. Secondary analyses that were not defined a priori were considered exploratory and hypothesis-generating. Regression analyses were performed using R version 4.2.1 (R Foundation for Statistical Computing).
In the primary analysis, unadjusted logistic regression was used to assess the relationship between pretreatment vitamin D insufficiency and grade ≥3 sensory CIPN. The association was then adjusted for the following covariates that have been reported to be associated with CIPN risk: age (in years), self-reported race (White vs Black vs other), body mass index, and paclitaxel treatment assignment (weekly [QW] or Q2W) via multivariable logistic regression. An exploratory model including all the covariates except race was conducted to explore the possible confounding effect of race. The interaction terms were tested between any covariates and vitamin D insufficiency.
Secondary analyses were conducted similarly to the primary analysis using slight variations of the independent and dependent variables. The combination of grade ≥3 sensory and motor CIPN was used as a secondary dependent variable. Alternative independent variables included vitamin D3 insufficiency (≤20 ng/mL), total vitamin D deficiency (≤12 ng/mL), and total vitamin D concentration as a continuous variable. The optimal total vitamin D threshold was determined based on the area under the curve (AUC) of the receiver operating characteristic curve.
Exploratory analysis of the association was examined within the strata of each covariate using simple logistic regression. Multivariable logistic regression with covariate adjustment was also conducted in each self-reported racial group (Black, White, and other). The prevalence of pretreatment vitamin D insufficiency was compared between self-reported racial groups via simple logistic regression with a 2-sided α level of .05.
Vitamin D Deficiency Mouse Experiments
Adult (50% male and 50% female) C57BL/6J (JAX mice; The Jackson Laboratory) were acclimated and housed in a temperature-, light-, and humidity-controlled facility at Virginia Commonwealth University. Mice were randomly assigned 1:1 to a regular diet (RD) or vitamin D–deficient diet (VDD) by withdrawing vitamin D from the diet (Research Diets Inc.) for 2 months, which has been demonstrated to cause 25-hydroxy vitamin D3 deficiency in C57BL/6J mice.25 Mice were then randomly assigned 1:1 to intraperitoneal administration of 2 mg/kg paclitaxel or vehicle (1:1:18 mixture of 200-proof ethanol, Kolliphor, and distilled water) every other day for 4 doses. Mechanical sensitivity threshold, a commonly used mouse phenotype of sensory neurotoxicity, was tested using von Frey filaments by a study team member blinded to treatment assignments.26,27 The mechanical threshold is expressed as the grams of force required to elicit hind paw withdrawal in 50% of the animals. Mechanical sensitivity was tested before and after 4 and 8 weeks of RD or VDD and before and at 3, 7, 14, and 21 days after paclitaxel or vehicle administration. Mechanical hypersensitivity data in mice were expressed as the mean ± SEM and analyzed using 3-way ANOVA via GraphPad Prism 9.3.0 software with an α level of .05.
Results
Study Patient Characteristics
Of the 1,191 female patients included in the analysis, the mean age of the analysis cohort was 51.1 years (SEM, 9.9 years). Patients were mostly White (83.7% vs 9.2% Black), and 52.5% received Q2W paclitaxel treatment (Table 1). The demographics were similar to the overall S0221 parent trial cohort, but the analysis cohort was purposefully enriched for patients who experienced CIPN. In all, 397 (33.3%) patients had pretreatment vitamin D insufficiency, 195 (16.4%) developed grade ≥3 sensory CIPN, and 204 (17.1%) developed grade ≥3 sensory or motor CIPN.
Clinical Data for Analyzed Cohort
Vitamin D Insufficiency as a Risk Factor for CIPN
Patients who were older (odds ratio [OR], 1.02; 95% CI, 1.01–1.04; P=.005), self-reported as Black (OR, 2.48; 95% CI, 1.57–3.86; P<.001) or other race (OR, 1.84; 95% CI, 1.06–3.07; P=.025), or were randomized to Q2W paclitaxel (OR, 2.37; 95% CI, 1.73–3.29; P<.001) had a higher incidence of CIPN. In the primary univariate analysis, patients with pretreatment vitamin D insufficiency had a higher incidence of grade ≥3 sensory CIPN than those who were vitamin D sufficient (20.7% vs 14.2%; OR, 1.57; 95% CI, 1.14–2.15; P=.005) (Table 2, Figure 1). The association retained significance after adjusting for age and paclitaxel schedule (adjusted OR [aOR], 1.65; 95% CI, 1.18–2.30; P=.003) but did not retain significance after additionally adjusting for self-reported race (aOR, 1.39; 95% CI, 0.98–1.97; P=.066) (Table 2). In subgroup analyses, CIPN incidence was higher in vitamin D–insufficient patients in the middle age tertile, top body mass index tertile, and paclitaxel Q2W subgroups (Figure 2), but there was no significant interaction between any covariates and vitamin D insufficiency (data not shown).
ORs of Unadjusted and Multivariable Models of Sensory Peripheral Neuropathy Predicted by Vitamin D Insufficiency
In secondary analyses, when using the combination of grade ≥3 sensory and motor CIPN as the dependent variable, pretreatment vitamin D insufficiency was significantly associated with CIPN, including when adjusting for self-reported race (supplemental eTable 1). The results were not meaningfully different when using vitamin D3 insufficiency, vitamin D deficiency, or vitamin D concentrations as the independent variable (supplemental eTable 2). The optimal vitamin D threshold was 17 ng/mL, but the prediction performance was not meaningfully different (17 ng/mL AUC, 55.9% vs 20 ng/mL AUC, 55.2%; supplemental eFigure 2).
Racial Disparity in Vitamin D Insufficiency and CIPN
Compared with White patients, Black patients had a higher prevalence of vitamin D insufficiency (28.2% White vs 77.1% Black vs 37.6% other; Black vs White OR, 8.56; 95% CI, 5.44–13.92; P<.001) and a higher incidence of sensory CIPN (14.3% White vs 29.4% Black vs 23.5% other; Black vs White OR, 2.48; 95% CI, 1.57–3.86; P<.001) (Table 2). The association of vitamin D insufficiency with sensory CIPN was not statistically significant in any self-reported racial subgroup but was nominally similar in the White (OR, 1.40; 95% CI, 0.95–2.27) and Black cohorts (OR, 1.42; 95% CI, 0.53–4.27) (Figure 2, supplemental eTable 3).
Vitamin D Deficiency Causes Mechanical Sensitivity in Mice
Mice receiving VDD displayed a significant and progressive decline in the mechanical sensitivity threshold and had greater mechanical sensitivity than mice receiving RD at weeks 4 (P=.037) and 8 (P=.016) (Figure 3A). Following the 8-week VDD, mice receiving 4 doses of paclitaxel (VDD-PAC) displayed a significant and progressive decline in mechanical sensitivity compared with vehicle-treated mice receiving RD (RD-VEH) (Figure 3B). VDD-PAC mice had significantly greater mechanical sensitivity compared with paclitaxel-treated mice receiving RD (RD-PAC) on day 14 (P=.044) (Figure 3B).
Discussion
Our prospective-retrospective analysis of the SWOG S0221 clinical trial confirms that patients with pretreatment vitamin D insufficiency have a higher incidence of CIPN and suggests that this may partially explain the higher incidence of CIPN in Black patients. The mouse experiment indicates that vitamin D deficiency directly causes neurotoxicity and sensitization to paclitaxel.
Prior studies have reported that patients with vitamin D insufficiency have a higher risk of CIPN from paclitaxel.11,12 In our prior pilot study, patients with vitamin D insufficiency reported more severe sensory CIPN on the CIPN20 questionnaire (36 vs 16 [0 to 100 scale]).12 Another group also found lower pretreatment vitamin D concentrations (10.3 vs 15.4 ng/mL) in paclitaxel-treated patients who developed CIPN.11 Our analysis of data from S0221 confirms the association between vitamin D insufficiency and higher CIPN incidence and satisfies the 3 requirements of a confirmatory prospective-retrospective study: (1) enough patients from a prospective trial to have adequate statistical power and be representative of the parent trial, (2) an analytically validated test, and (3) a prespecified statistical analysis plan.15
Vitamin D insufficiency has also been suggested to be a risk factor for CIPN caused by other neurotoxic anticancer agents, including oxaliplatin,28 bortezomib, and thalidomide,29–32 and in other disease states, including diabetic neuropathy33 and autoimmune-mediated CIPN.34,35 Although this correlative association could be due to confounding from an unrelated variable such as diet or lifestyle, our animal study suggests that vitamin D deficiency directly causes mechanical hypersensitivity and sensitizes mice to paclitaxel. A recent mouse study reported that vitamin D deficiency induces mechanical hypersensitivity through microglial activation in the brain and spinal cord,36 similar to the effects of paclitaxel,37–43 which provides a plausible mechanistic explanation for our finding. Vitamin D supplementation may ameliorate these effects by increasing axon regeneration and myelination, possibly via stimulation of nerve growth factor44 or inhibition of proinflammatory cytokines,45,46 which we are testing in ongoing murine studies.25,47,48
It is unclear why Black patients have a higher incidence of CIPN49,50 and neuropathy from other etiologies.51,52 Our analysis suggests this may be due to the higher incidence of vitamin D insufficiency,53 which has been previously suggested.52 An alternative possibility is that the apparent association with vitamin D and CIPN is due to racial confounding; however, our mouse study demonstrates a direct causal effect of vitamin D insufficiency on neurotoxicity, strengthening the hypotheses that vitamin D insufficiency increases CIPN risk and may be partially responsible for the higher CIPN incidence in Black patients.
Validation of vitamin D insufficiency as a CIPN risk factor justifies testing vitamin D supplementation to prevent CIPN in vitamin D–insufficient patients receiving paclitaxel. A previous analysis in S0221 found that use of vitamin d–containing multivitamins was preventive of CIPN,17 and there is a case report of vitamin D supplementation improving CIPN in a patient receiving bortezomib.31 However, the effect of vitamin D supplementation on CIPN is not evaluable in existing prospective clinical trials that did not report CIPN,54 did not have a no-supplement comparator arm,55 or used different taxane doses between the supplement and no-supplement arms.56 Prospective clinical trials of vitamin D supplementation to prevent paclitaxel-induced peripheral neuropathy are needed57,58; such a phase II trial is ongoing (ClinicalTrials.gov identifier: NCT05259527). Outside of CIPN, vitamin D supplements have been suggested to improve diabetic neuropathy in vitamin D–insufficient patients.59 Considering the minimal cost and toxicity of vitamin D supplementation and the use of vitamin D to prevent bone loss in patients with breast cancer who are receiving aromatase inhibitors,60 vitamin D supplementation may be a reasonable intervention to prevent CIPN during paclitaxel treatment in some high-risk patients, even in the absence of confirmatory clinical trial evidence.
This prospective-retrospective analysis was conducted in a large prospective clinical trial cohort using a validated assay and prespecified analysis plan.15 Despite these strengths, this study has several limitations that should be acknowledged. First, S0221 did not collect grade 2 CIPN or document detailed paclitaxel dosing information. It is possible that some patients who would have experienced grade ≥3 CIPN were misclassified as no-CIPN controls because of paclitaxel treatment alteration.61 Second, the CTCAE is considered less sensitive than patient-reported outcome (PRO) questionnaires for detecting subjective toxicities, including CIPN.1 We chose to use CTCAE data as the primary CIPN endpoint because they were available in all trial participants, whereas PRO data62 were available only in the subset of patients that participated in the DELCaP substudy17 and because of our concerns regarding the use of PRO data in CIPN biomarker analyses.63 Third, S0221 did not collect data on other CIPN risk factors, including preexisting peripheral neuropathy and diabetes status.52 Fourth, there was a limited number of non-White participants in this analysis, and larger numbers are needed to further elucidate the interplay between race, vitamin D, and CIPN, which perhaps can be achieved in the EAZ171 (NCT04001829) study. Finally, we plan to investigate whether this association also applies to paclitaxel and docetaxel used in other tumor types by using data and samples collected within the prospective observational SWOG S1714 study (NCT03939481). Confirmation of the association in a second prospective-retrospective analysis would satisfy the fourth and final criteria for prospective-retrospective biomarker validation.15
Conclusions
Pretreatment vitamin D insufficiency is associated with a higher risk of CIPN from paclitaxel. Prospective trials are needed to investigate the potential effectiveness of vitamin D supplementation for CIPN prevention. Vitamin D insufficiency may be a clinically useful biomarker to inform personalized supplementation to reduce CIPN occurrence, improve long-term quality of life, and perhaps enable patients to remain on effective paclitaxel treatment and improve survival.
Acknowledgments
We want to thank Susan E. McCann for her insights and contribution to the analysis and the manuscript before she died. She will be greatly missed.
References
- 1.↑
Molassiotis A, Cheng HL, Lopez V, et al. Are we mis-estimating chemotherapy-induced peripheral neuropathy? Analysis of assessment methodologies from a prospective, multinational, longitudinal cohort study of patients receiving neurotoxic chemotherapy. BMC Cancer 2019;19:132.
- 2.↑
Seidman AD, Berry D, Cirrincione C, et al. Randomized phase III trial of weekly compared with every-3-weeks paclitaxel for metastatic breast cancer, with trastuzumab for all HER-2 overexpressors and random assignment to trastuzumab or not in HER-2 nonoverexpressors: final results of Cancer and Leukemia Group B protocol 9840. J Clin Oncol 2008;26:1642–1649.
- 3.↑
Rivera DR, Ganz PA, Weyrich MS, et al. Chemotherapy-associated peripheral neuropathy in patients with early-stage breast cancer: a systematic review. J Natl Cancer Inst 2018;110:djx140.
- 4.↑
Hershman DL, Unger JM, Crew KD, et al. Two-year trends of taxane-induced neuropathy in women enrolled in a randomized trial of acetyl-l-carnitine (SWOG S0715). J Natl Cancer Inst 2018;110:669–676.
- 5.↑
Simon NB, Danso MA, Alberico TA, et al. The prevalence and pattern of chemotherapy-induced peripheral neuropathy among women with breast cancer receiving care in a large community oncology practice. Qual Life Res 2017;26:2763–2772.
- 6.↑
Loprinzi CL, Lacchetti C, Bleeker J, et al. Prevention and management of chemotherapy-induced peripheral neuropathy in survivors of adult cancers: ASCO guideline update. J Clin Oncol 2020;38:3325–3348.
- 7.↑
Smith EM, Pang H, Cirrincione C, et al. Effect of duloxetine on pain, function, and quality of life among patients with chemotherapy-induced painful peripheral neuropathy: a randomized clinical trial. JAMA 2013;309:1359–1367.
- 8.↑
Loibl S, Skacel T, Nekljudova V, et al. Evaluating the impact of relative total dose intensity (RTDI) on patients’ short and long-term outcome in taxane- and anthracycline-based chemotherapy of metastatic breast cancer- a pooled analysis. BMC Cancer 2011;11:131.
- 9.↑
Cespedes Feliciano EM, Chen WY, Lee V, et al. Body composition, adherence to anthracycline and taxane-based chemotherapy, and survival after nonmetastatic breast cancer. JAMA Oncol 2020;6:264–270.
- 10.↑
Lustberg M, Loprinzi C, eds. Diagnosis, Management and Emerging Strategies for Chemotherapy-Induced Neuropathy. Springer Cham; 2021.
- 11.↑
Grim J, Ticha A, Hyspler R, et al. Selected risk nutritional factors for chemotherapy-induced polyneuropathy. Nutrients 2017;9:535.
- 12.↑
Jennaro TS, Fang F, Kidwell KM, et al. Vitamin D deficiency increases severity of paclitaxel-induced peripheral neuropathy. Breast Cancer Res Treat 2020;180:707–714.
- 13.↑
Omenn GS, Deangelis CD, Demets DL, et al. Evolution of Translational Omics: Lessons Learned and the Path Forward. National Academies Press; 2012.
- 14.↑
Patterson SD, Cohen N, Karnoub M, et al. Prospective-retrospective biomarker analysis for regulatory consideration: white paper from the industry pharmacogenomics working group. Pharmacogenomics 2011;12:939–951.
- 15.↑
Simon RM, Paik S, Hayes DF. Use of archived specimens in evaluation of prognostic and predictive biomarkers. J Natl Cancer Inst 2009;101:1446–1452.
- 16.↑
Budd GT, Barlow WE, Moore HC, et al. SWOG S0221: a phase III trial comparing chemotherapy schedules in high-risk early-stage breast cancer. J Clin Oncol 2015;33:58–64.
- 17.↑
Zirpoli GR, McCann SE, Sucheston-Campbell LE, et al. Supplement use and chemotherapy-induced peripheral neuropathy in a cooperative group trial (S0221): the DELCaP study. J Natl Cancer Inst 2017;109:djx098.
- 18.↑
Trotti A, Colevas AD, Setser A, et al. CTCAE v3.0: development of a comprehensive grading system for the adverse effects of cancer treatment. Semin Radiat Oncol 2003;13:176–181.
- 19.↑
Mongiovi JM, Zirpoli GR, Cannioto R, et al. Associations between self-reported diet during treatment and chemotherapy-induced peripheral neuropathy in a cooperative group trial (S0221). Breast Cancer Res 2018;20:146.
- 20.↑
Binkley N, Dawson-Hughes B, Durazo-Arvizu R, et al. Vitamin D measurement standardization: the way out of the chaos. J Steroid Biochem Mol Biol 2017;173:117–121.
- 21.↑
Makowski AJ, Rathmacher JA, Horst RL, et al. Simplified 25-hydroxyvitamin D standardization and optimization in dried blood spots by LC-MS/MS. J AOAC Int 2017;100:1328–1336.
- 22.↑
McCullough ML, Zoltick ES, Weinstein SJ, et al. Circulating vitamin D and colorectal cancer risk: an international pooling project of 17 cohorts. J Natl Cancer Inst 2019;111:158–169.
- 23.↑
Weinstein SJ, Purdue MP, Smith-Warner SA, et al. Serum 25-hydroxyvitamin D, vitamin D binding protein and risk of colorectal cancer in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Int J Cancer 2015;136:E654–664.
- 24.↑
Giustina A, Adler RA, Binkley N, et al. Controversies in vitamin D: summary statement from an international conference. J Clin Endocrinol Metab 2019;104:234–240.
- 25.↑
Kemény LV, Robinson KC, Hermann AL, et al. Vitamin D deficiency exacerbates UV/endorphin and opioid addiction. Sci Adv 2021;7:eabe4577.
- 26.↑
Bagdas D, AlSharari SD, Freitas K, et al. The role of alpha5 nicotinic acetylcholine receptors in mouse models of chronic inflammatory and neuropathic pain. Biochem Pharmacol 2015;97:590–600.
- 27.↑
Chaplan SR, Bach FW, Pogrel JW, et al. Quantitative assessment of tactile allodynia in the rat paw. J Neurosci Methods 1994;53:55–63.
- 28.↑
Yildirim N, Cengiz M. Predictive clinical factors of chronic peripheral neuropathy induced by oxaliplatin. Support Care Cancer 2020;28:4781–4788.
- 29.↑
Oortgiesen BE, Kroes JA, Scholtens P, et al. High prevalence of peripheral neuropathy in multiple myeloma patients and the impact of vitamin D levels, a cross-sectional study. Support Care Cancer 2022;30:271–278.
- 30.↑
Wang J, Udd KA, Vidisheva A, et al. Low serum vitamin D occurs commonly among multiple myeloma patients treated with bortezomib and/or thalidomide and is associated with severe neuropathy. Support Care Cancer 2016;24:3105–3110.
- 31.↑
Clement Z, Ashford M, Sivakumaran S. Vitamin D deficiency in a man with multiple myeloma. N Am J Med Sci 2011;3:469–471.
- 32.↑
Nath K, Ganeshalingam V, Ewart B, et al. A retrospective analysis of the prevalence and clinical outcomes of vitamin D deficiency in myeloma patients in tropical Australia. Support Care Cancer 2020;28:1249–1254.
- 33.↑
Zhang B, Zhao W, Tu J, et al. The relationship between serum 25-hydroxyvitamin D concentration and type 2 diabetic peripheral neuropathy: a systematic review and a meta-analysis. Medicine (Baltimore) 2019;98:e18118.
- 34.↑
Yesil H, Sungur U, Akdeniz S, et al. Association between serum vitamin D levels and neuropathic pain in rheumatoid arthritis patients: a cross-sectional study. Int J Rheum Dis 2018;21:431–439.
- 35.↑
Garcia-Carrasco M, Jiménez-Herrera EA, Gálvez-Romero JL, et al. Vitamin D and Sjögren syndrome. Autoimmun Rev 2017;16:587–593.
- 36.↑
Alessio N, Belardo C, Trotta MC, et al. Vitamin D deficiency induces chronic pain and microglial phenotypic changes in mice. Int J Mol Sci 2021;22:3604.
- 37.↑
Liu CC, Lu N, Cui Y, et al. Prevention of paclitaxel-induced allodynia by minocycline: effect on loss of peripheral nerve fibers and infiltration of macrophages in rats. Mol Pain 2010;6:76.
- 38.↑
Perera PY, Qureshi N, Vogel SN. Paclitaxel (taxol)-induced NF-kappaB translocation in murine macrophages. Infect Immun 1996;64:878–884.
- 39.↑
Peters CM, Jimenez-Andrade JM, Jonas BM, et al. Intravenous paclitaxel administration in the rat induces a peripheral sensory neuropathy characterized by macrophage infiltration and injury to sensory neurons and their supporting cells. Exp Neurol 2007;203:42–54.
- 40.↑
Pevida M, Lastra A, Hidalgo A, et al. Spinal CCL2 and microglial activation are involved in paclitaxel-evoked cold hyperalgesia. Brain Res Bull 2013;95:21–27.
- 41.↑
Toma W, Kyte SL, Bagdas D, et al. The α7 nicotinic receptor silent agonist R-47 prevents and reverses paclitaxel-induced peripheral neuropathy in mice without tolerance or altering nicotine reward and withdrawal. Exp Neurol 2019;320:113010.
- 42.↑
Wanderley CW, Colón DF, Luiz JPM, et al. Paclitaxel reduces tumor growth by reprogramming tumor-associated macrophages to an M1 profile in a TLR4-dependent manner. Cancer Res 2018;78:5891–5900.
- 43.↑
Zhang H, Li Y, de Carvalho-Barbosa M, et al. Dorsal root ganglion infiltration by macrophages contributes to paclitaxel chemotherapy-induced peripheral neuropathy. J Pain 2016;17:775–786.
- 44.↑
Faye PA, Poumeaud F, Miressi F, et al. Focus on 1,25-dihydroxyvitamin D3 in the peripheral nervous system. Front Neurosci 2019;13:348.
- 45.↑
Plantone D, Primiano G, Manco C, et al. Vitamin D in neurological diseases. Int J Mol Sci 2022;24:87.
- 46.↑
Karonova T, Stepanova A, Bystrova A, et al. High-dose vitamin D supplementation improves microcirculation and reduces inflammation in diabetic neuropathy patients. Nutrients 2020;12:2518.
- 47.↑
Caillaud M, Patel NH, White A, et al. Targeting peroxisome proliferator-activated receptor-α (PPAR-α) to reduce paclitaxel-induced peripheral neuropathy. Brain Behav Immun 2021;93:172–185.
- 48.↑
Caillaud M, Patel NH, Toma W, et al. A fenofibrate diet prevents paclitaxel-induced peripheral neuropathy in mice. Cancers (Basel) 2020;13:69.
- 49.↑
Schneider BP, Shen F, Jiang G, et al. Impact of genetic ancestry on outcomes in ECOG-ACRIN-E5103. JCO Precis Oncol. Published online August 21, 2017. doi:10.1200/PO.17.00059
- 50.↑
Hertz DL, Roy S, Motsinger-Reif AA, et al. CYP2C8*3 increases risk of neuropathy in breast cancer patients treated with paclitaxel. Ann Oncol 2013;24:1472–1478.
- 51.↑
Anziska Y, Helzner EP, Crystal H, et al. The relationship between race and HIV-distal sensory polyneuropathy in a large cohort of US women. J Neurol Sci 2012;315:129–132.
- 52.↑
Soderstrom LH, Johnson SP, Diaz VA, et al. Association between vitamin D and diabetic neuropathy in a nationally representative sample: results from 2001-2004 NHANES. Diabet Med 2012;29:50–55.
- 53.↑
Liu X, Baylin A, Levy PD. Vitamin D deficiency and insufficiency among US adults: prevalence, predictors and clinical implications. Br J Nutr 2018;119:928–936.
- 54.↑
Beer TM, Ryan CW, Venner PM, et al. Double-blinded randomized study of high-dose calcitriol plus docetaxel compared with placebo plus docetaxel in androgen-independent prostate cancer: a report from the ASCENT investigators. J Clin Oncol 2007;25:669–674.
- 55.↑
Ng K, Nimeiri HS, McCleary NJ, et al. Effect of high-dose vs standard-dose vitamin D3 supplementation on progression-free survival among patients with advanced or metastatic colorectal cancer: the SUNSHINE randomized clinical trial. JAMA 2019;321:1370–1379.
- 56.↑
Scher HI, Jia X, Chi K, et al. Randomized, open-label phase III trial of docetaxel plus high-dose calcitriol versus docetaxel plus prednisone for patients with castration-resistant prostate cancer. J Clin Oncol 2011;29:2191–2198.
- 57.↑
Dorsey SG, Kleckner IR, Barton D, et al. The National Cancer Institute clinical trials planning meeting for prevention and treatment of chemotherapy-induced peripheral neuropathy. J Natl Cancer Inst 2019;111:531–537.
- 58.↑
Gewandter JS, Brell J, Cavaletti G, et al. Trial designs for chemotherapy-induced peripheral neuropathy prevention: ACTTION recommendations. Neurology 2018;91:403–413.
- 59.↑
Yammine K, Wehbe R, Assi C. A systematic review on the efficacy of vitamin D supplementation on diabetic peripheral neuropathy. Clin Nutr 2020;39:2970–2974.
- 60.↑
Shapiro CL, Van Poznak C, Lacchetti C, et al. Management of osteoporosis in survivors of adult cancers with nonmetastatic disease: ASCO clinical practice guideline. J Clin Oncol 2019;37:2916–2946.
- 61.↑
Speck RM, Sammel MD, Farrar JT, et al. Impact of chemotherapy-induced peripheral neuropathy on treatment delivery in nonmetastatic breast cancer. J Oncol Pract 2013;9:e234–240.
- 62.↑
Cella D, Peterman A, Hudgens S, et al. Measuring the side effects of taxane therapy in oncology: the functional assessment of cancer therapy-taxane (FACT-taxane). Cancer 2003;98:822–831.
- 63.↑
Hertz DL. Concerns regarding use of patient-reported outcomes in biomarker studies of chemotherapy-induced peripheral neuropathy. Pharmacogenomics J 2019;19:411–416.