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Copyright 2008 Multimed Inc. Chemotherapy- and cancer-related nausea and vomiting Correspondence to: David Warr, Department of Medicine, Room 5-204, Princess Margaret Hospital, 610 University Avenue, Toronto, Ontario M5G 2M9. E-mail: david.warr/at/uhn.on.ca This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Approximately one half of cancer patients will experience nausea or vomiting during the course of their disease either because of the cancer itself or because of their treatment. Emesis attributable to cancer warrants a careful investigation to determine whether a treatable underlying cause is responsible. Interventions using dexamethasone and octreotide may reduce vomiting attributable to bowel obstruction. In the absence of a bowel obstruction or a correctable cause, the usual approach is a sequential trial of antiemetics guided by considerations of cost and side effects. Major progress in managing chemotherapy-induced emesis followed from the use of a combination of a corticosteroid and 5-hydroxytryptamine3 (5-HT3) receptor antagonist for moderately to highly emetogenic chemotherapy. Nevertheless, vomiting still occurred in approximately 40% of women receiving chemotherapy containing an anthracycline plus cyclophosphamide and in approximately 50% of patients receiving high-dose cisplatin. The addition of aprepitant, a neurokinin 1 receptor antagonist, improved control of emesis by a further 15%–20%, and that agent is now recommended as part of standard antiemetic therapy for patients at high risk of emesis. Based largely on anecdotal experience, cannabinoids and olanzapine are sometimes also recommended in patients with refractory emesis. Phase iii trials are required to confirm their efficacy as add-ons to a corticosteroid, a 5-HT3 receptor antagonist, and possibly aprepitant. Keywords: Nausea, vomiting, emesis, chemotherapy, 5-hydroxy-tryptamine3, aprepitant, neurokinin 1. INTRODUCTION Nausea and vomiting are common problems in cancer patients throughout the trajectory of their illness. Whether these patients are receiving high-dose cisplatin 1 with the best available antiemetic therapy or are experiencing the advanced stages of cancer 2, approximately one half will experience nausea or vomiting, or both. The causes of these distressing symptoms are diverse, and they include medication, radiation therapy, and the effect of the cancer itself. Table I lists some examples. The present article reviews the approach to emesis attributable to cancer or chemotherapy.
2. DISCUSSION Although nausea and vomiting are closely related, some patients experience one symptom without the other. For example, mild-to-moderate nausea is often not accompanied by retching or vomiting. On the other hand, some patients with brain metastases or esophageal obstruction report vomiting without prior nausea. The physiology of nausea is not well understood 3. In choosing a pharmacologic approach, no distinction is usually made between vomiting and nausea; however, the literature suggests that it is easier to eliminate vomiting than nausea 4,5. 2.1 Cancer-Induced Emesis The first step in the approach to cancer-induced emesis is to establish whether a remediable cause is present. A careful history, physical examination, laboratory tests, and (sometimes) imaging are required (Table II). How often a diagnosis can be made of the underlying cause for emesis is unclear.
A prospective study of 121 patients determined that 50% were experiencing nausea or vomiting or both on admission to a hospice5. The causes were diagnosed as “chemical” (metabolic, drug-related, infectious) in 33%, impaired gastric emptying (tumour, hepatomegaly, drug-related, ascites, other) in 44%, visceral or serosal (bowel obstruction, other) in 31%, intracranial in 8%, and anxiety in 7%. For each cause, the authors had defined, in advance, a pharmacologic approach that included one or more of haloperidol, metoclopramide, cyclizine, dexamethasone, or a benzodiazepine. Indeterminate causes were treated with levomepromazine. Although this prospective study reported control of vomiting in 89% of patients, several problems arise in applying the results to practise. The criteria for diagnosing the causes are not listed, and no “gold standard” exists to determine the accuracy of the diagnoses. Of the study patients, 50% were already on an “appropriate” antiemetic at the time of admission, raising questions about whether the recommended pharmacologic approach was actually responsible for the improvement. After 1 week, 48% of patients had dropped out of the study. The article also did not state how often a correctable underlying cause—for example, hypercalcemia—was found. A valid pharmacologic approach to the problem of nausea and vomiting requires a good evidence base. Unfortunately, very few controlled trials on this subject have been conducted. A systematic review of the efficacy of antiemetics in treating nausea in advanced cancer was able to find only seven randomized clinical trials: two for bowel obstruction, one for opioid-related nausea, and three in which several causes (such as bowel obstruction, brain metastases, metabolic disturbances, and medications) had been excluded6. The authors concluded that
These conclusions were weakened by small sample sizes and lack of a double-blind design in some of the analyzed trials. The approach to cancer-induced nausea and vomiting therefore remains largely empirical:
For other causes of emesis, empiric trials of antiemetics (Table III) remain the only source of guidance. Antiemetics are typically chosen based on considerations of past practice, cost, and adverse effects. Phenothiazines or a butyrophenone, substituted benzamides, and possibly antihistamines are tried before 5-HT3 receptor antagonists or cannabinoids. The use of aprepitant in this setting has not been reported.
2.2 Chemotherapy-Induced Nausea and Vomiting Before the 1980s, chemotherapy-induced vomiting occurred in a preponderance of patients who received cisplatin or doxorubicin. In the 1990s, an antiemetic combination of a corticosteroid and a 5-HT3 receptor antagonist became common practice for many cyto-toxic regimens. By the early part of that decade, that antiemetic combination had had a noticeable impact on admissions to hospital for control of emesis, leading to cost savings 9. But despite that progress, substantial problems with nausea and vomiting remained. In two large randomized trials, 50% of patients receiving high-dose cisplatin still experienced vomiting and 58% experienced nausea in the face of standard antiemetic therapy 1. Although traditionally regarded as “moderately emetogenic,” anthracycline and cyclophosphamide chemotherapy for breast cancer evoked vomiting in 41% of patients and nausea in 67% following ondansetron and dexamethasone 10. Those outcomes were vastly better than the outcomes seen in the 1980s, but considerable room for improvement remained. Several large comparative studies showed no difference in efficacy between ondansetron, granisetron, and dolasetron 11,12. The prevailing belief was that all 5-HT3 receptor antagonists were equivalent in efficacy and in side effects when delivered in the recommended doses. That paradigm was challenged by palonosetron, an intravenous 5-HT3 receptor antagonist with a sufficiently long half life that a single administration was sufficient 13. In patients who received moderately emetogenic chemotherapy, two large randomized trials showed superiority for palonosetron over ondansetron 14 and dolasetron 15. In contrast, palonosetron appeared to be equivalent to ondansetron in patients who received high-dose cisplatin 16. Despite those results, the American Society of Clinical Oncology (asco) guide- lines do not recognize palonosetron as the 5-HT3 receptor antagonist of choice, because the therapies used in the study comparator arms were not regarded as best standard therapy 17. The true role for palonosetron will be confidently established only by randomized trials in which the standard therapy conforms to recommended practice. Also in the 1990s, a new of class of antiemetics was discovered: the neurokinin 1 (NK1) receptor antagonists 18 . The NK1 receptor has substance P as its natural ligand and is present both peripherally and centrally. Aprepitant is the only example of the NK1 antagonist class that has proceeded through phase iii testing. Aprepitant is commercially available in many countries around the world. Its efficacy has been evaluated in four phase iii double-blind randomized studies—three with high-dose cisplatin 19–21 and one with chemotherapy containing an anthracycline plus cyclophosphamide for breast cancer 10. The standard therapy arms contained ondansetron and dexamethasone; in the experimental arm, aprepitant in the currently approved dose and schedule was added to ondansetron and dexamethasone. All trials reported primary endpoints that were statistically significantly superior in the group receiving aprepitant (Table IV). A complete response was defined as an absence of retching or vomiting and no use of an “as-needed” antiemetic.
The cisplatin studies showed a 14%–20% absolute difference in complete response when aprepitant was added; in moderately emetogenic chemotherapy, the difference was only 9%. The apparently lesser improvement with the addition of an NK1 receptor antagonist to chemotherapy containing anthracycline plus cyclophosphamide was further explored by looking at nausea separately from vomiting or retching. Aprepitant had no detectable effect on nausea attributable to moderately emetogenic chemotherapy 10, but a statistically significant improvement was observed in the pivotal cisplatin studies 1. In contrast, for vomiting or retching alone, the superiority in the aprepitant groups was similar across the phase iii studies: a 17% difference in the moderately emetogenic trial and a 14.3%-to-22.7% difference in the cisplatin trials (Table IV). Thus, the improved control of vomiting provided by aprepitant was approximately the same whether the chemotherapy was high-dose cisplatin or cyclophosphamide and doxorubicin; however, the beneficial effect of aprepitant on nausea seemed to be limited to settings involving high-dose cisplatin. The reason for the difference is not known. Because aprepitant is a moderate inhibitor of the cytochrome P450 enzyme (CYP3A4), concern initially arose about whether aprepitant might affect the clearance of taxanes and vinca alkaloids that are metabolized by that enzyme. Adverse effects in the aprepitant-containing arms of the phase iii trials appeared very similar to those seen in standard therapy, with no trends across the studies even though patients commonly received concomitant taxanes, vinorelbine, or etoposide 1,10. Subsequent pharmacokinetic studies that showed no effect of aprepitant on the clearance of docetaxel 22 or vinorelbine 23 were consistent with the foregoing observations. Although no interaction with intravenous medications has thus far been demonstrated, aprepitant may have clinically relevant interactions with oral agents that have an extensive first-pass metabolism connected with CYP3A4 in the bowel wall. For example, dexamethasone is metabolized by CYP3A4, and co-administration with aprepitant results in a doubling of the area under the curve of the corticosteroid24. For that reason, the phase iii clinical trials were designed to deliver approximately one half the dose of dexamethasone in the group that received aprepitant. Aprepitant would also be expected to temporarily increase the blood levels of other oral agents metabolized by CYP3A4—as do ketoconazole, erythromycin, diltiazem, and a number of other commonly prescribed medications. Through induction of enzymes, aprepitant reduces warfarin levels by approximately one third 25, and the aprepitant product monograph indicates that aprepitant may reduce the efficacy of the birth control pill. Because aprepitant itself is metabolized by CYP3A4, strong inducers of that enzyme such as rifampin and phenytoin may lower blood levels of the drug sufficiently to make it ineffective. Aprepitant is an oral medication. It supplied as a 3-day pack: 125 mg on day 1, and 80 mg on each of days 2 and 3. Approval is being sought for a single intravenous dose of a prodrug that yields an area under the curve similar to that seen with oral aprepitant. Standard antiemetic therapy recommended by asco 17 and the Multinational Association for Supportive Care in Cancer 26 now includes aprepitant for chemotherapy with cisplatin and with anthracycline plus cyclophosphamide. Still, several questions remain about aprepitant use:
Aprepitant is an important step forward, but some patients still vomit or experience substantial nausea despite its use. In addition, aprepitant is not available in some countries, and like the 5-HT3 receptor antagonists, it is relatively expensive and may therefore not be an option for some patients. Other agents that might be added include a dopamine receptor antagonist (for example, prochlorperazine), a cannabinoid (nabilone or dronabinol), and the atypical antipsychotic olanzapine. Prochlorperazine appears to have very modest effects on chemotherapy-induced nausea and vomiting 27. Cannabinoids have some anecdotal support, but the data from clinical trials antedate the introduction of 5-HT3 receptor antagonists, and in recommended doses, significant problems with sedation and dysphoria arise. Olanzapine blocks multiple receptors, including dopamine receptors 28. Anecdotal accounts and phase ii studies suggest an important antiemetic effect 29,30, but phase iii data are not yet available. Tables V and VI outline a reasonable approach to antiemetic therapy that is consistent with the available evidence.
3. SUMMARY Cancer-related nausea results from a wide variety of causes, some of which cannot be clearly established by any investigation. Although therapy that aims to correct the underlying cause is rational, for many patients, such an approach is not possible. Few randomized trials have been conducted in this setting, and the sample sizes in the trials that have been conducted are small. The use of a corticosteroid or octreotide for bowel obstruction is supported by randomized trials. The 5-HT3 receptor antagonists have not been established to be efficacious for nausea resulting from opioid administration, but they may be helpful for nausea of uncertain origin in patients with advanced cancer. Given the limited data from clinical trials, a sequential pharmacologic approach based largely on past practise and considerations of costs and adverse effects is reasonable. Chemotherapy-related nausea and vomiting remains a problem in many patients despite the use of 5-HT3 receptor antagonists and dexamethasone. As an add-on to standard therapy, the NK1 receptor antagonist aprepitant reduces the likelihood of vomiting or retching in association with cisplatin or anthracycline-plus-cyclophosphamide chemotherapy by an absolute 15%–20%. Add-on aprepitant is recommended as first-line therapy by several prominent guidelines groups. Olanzapine and cannabinoids have been suggested as potentially useful interventions, but data from phase iii clinical trials are lacking. 4. REFERENCES 1. Warr DG, Grunberg SM, Gralla RJ, et al. The oral NK1 antagonist aprepitant for the prevention of acute and delayed chemotherapy-induced nausea and vomiting: pooled data from 2 randomised, double-blind, placebo controlled trials. Eur J Cancer. 2005;41:1278–85. [PubMed] 2. Wood GJ, Shega JW, Lynch B, Von Roenn JH. Management of intractable nausea and vomiting in patients at the end of life: “I was feeling nauseous all of the time ... nothing was working. JAMA. 2007;298:1196–207. [PubMed] 3. Sanger GJ, Andrews PL. Treatment of nausea and vomiting: gaps in our knowledge. Auton Neurosci. 2006;129:3–16. [PubMed] 4. Hickok JT, Roscoe JA, Morrow GR, King DK, Atkins JN, Fitch TR. Nausea and emesis remain significant problems of chemotherapy despite prophylaxis with 5-hydroxytryptamine-3 antiemetics: a University of Rochester James P. Wilmot Cancer Center Community Clinical Oncology Program Study of 360 cancer patients treated in the community. Cancer. 2003;97:2880–6. [PubMed] 5. Stephenson J, Davies A. An assessment of aetiology-based guidelines for the management of nausea and vomiting in patients with advanced cancer. Support Care Cancer. 2006;14:348–53. [PubMed] 6. Glare P, Pereira G, Kristjanson LJ, Stockler M, Tattersall M. Systematic review of the efficacy of antiemetics in the treatment of nausea in patients with far-advanced cancer. Support Care Cancer. 2004;12:432–40. [PubMed] 7. Laval G, Girardier J, Lassauniere JM, Leduc B, Haond C, Schaerer R. The use of steroids in the management of inoperable intestinal obstruction in terminal cancer patients: do they remove the obstruction? Palliat Med. 2000;14:3–10. [PubMed] 8. Mystakidou K, Tsilika E, Kalaidopoulou O, Chondros K, Georgaki S, Papadimitriou L. Comparison of octreotide administration vs conservative treatment in the management of inoperable bowel obstruction in patients with far advanced cancer: a randomized, double-blind, controlled clinical trial. Anticancer Res. 2002;22:1187–92. [PubMed] 9. Stewart DJ, Dahrouge S, Coyle D, Evans WK. Costs of treating and preventing nausea and vomiting in patients receiving chemotherapy. J Clin Oncol. 1999;17:344–51. [PubMed] 10. Warr DG, Hesketh PJ, Gralla RJ, et al. 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Gralla R, Lichinitser M, Van Der Vegt S, et al. Palonosetron improves prevention of chemotherapy-induced nausea and vomiting following moderately emetogenic chemotherapy: results of a double-blind randomized phase iii trial comparing single doses of palonosetron with ondansetron. Ann Oncol. 2003;14:1570–7. [PubMed] 15. Eisenberg P, Figueroa–Vadillo J, Zamora R, et al. Improved prevention of moderately emetogenic chemotherapy-induced nausea and vomiting with palonosetron, a pharmacologically novel 5-HT3 receptor antagonist: results of a phase iii, single-dose trial versus dolasetron. Cancer. 2003;98:2473–82. [PubMed] 16. Aapro MS, Grunberg SM, Manikhas GM, et al. A phase iii, double-blind, randomized trial of palonosetron compared with ondansetron in preventing chemotherapy-induced nausea and vomiting following highly emetogenic chemotherapy. Ann Oncol. 2006;17:1441–9. [PubMed] 17. Kris MG, Hesketh PJ, Somerfield MR, et al. American Society of Clinical Oncology guideline for antiemetics in oncology: update 2006. J Clin Oncol. 2006;24:2932–47. [PubMed] 18. Bountra C, Bunce K, Dale T, et al. Anti-emetic profile of a non-peptide neurokinin NK1 receptor antagonist, CP-99,994, in ferrets. Eur J Pharmacol. 1993;249:R3–4. [PubMed] 19. Hesketh PJ, Grunberg SM, Gralla RJ, et al. The oral neurokinin-1 antagonist aprepitant for the prevention of chemotherapy-induced nausea and vomiting: a multinational, randomized, double-blind, placebo-controlled trial in patients receiving high-dose cisplatin—the Aprepitant Protocol 052 Study Group. J Clin Oncol. 2003;21:4112–19. [PubMed] 20. Poli–Bigelli S, Rodrigues–Pereira J, Carides AD, et al. Addition of the neurokinin 1 receptor antagonist aprepitant to standard antiemetic therapy improves control of chemotherapy-induced nausea and vomiting. Results from a randomized, double-blind, placebo-controlled trial in Latin America. Cancer. 2003;97:3090–8. [PubMed] 21. Schmoll HJ, Aapro MS, Poli–Bigelli S, et al. Comparison of an aprepitant regimen with a multiple-day ondansetron regimen, both with dexamethasone, for antiemetic efficacy in high-dose cisplatin treatment. Ann Oncol. 2006;17:1000–6. [PubMed] 22. Nygren P, Hande K, Petty KJ, et al. Lack of effect of aprepitant on the pharmacokinetics of docetaxel in cancer patients. Cancer Chemother Pharmacol. 2005;55:609–16. [PubMed] 23. Loos WJ, de Wit R, Freedman SJ, et al. Aprepitant when added to a standard antiemetic regimen consisting of ondansetron and dexamethasone does not affect vinorelbine pharmacokinetics in cancer patients. Cancer Chemother Pharmacol. 2007;59:407–12. [PubMed] 24. McCrea JB, Majumdar AK, Goldberg MR, et al. Effects of the neurokinin1 receptor antagonist aprepitant on the pharmacokinetics of dexamethasone and methylprednisolone. Clin Pharmacol Ther. 2003;74:17–24. [PubMed] 25. Depre M, Van Hecken A, Oeyen M, et al. Effect of aprepitant on the pharmacokinetics and pharmacodynamics of warfarin. Eur J Clin Pharmacol. 2005;61:341–6. [PubMed] 26. Roila F, Hesketh PJ, Herrstedt J. Prevention of chemotherapy-and radiotherapy-induced emesis: results of the 2004 Perugia International Antiemetic Consensus Conference. Ann Oncol. 2006;17:20–8. [PubMed] 27. Hickok JT, Roscoe JA, Morrow GR, et al. 5-Hydroxy-tryptamine-receptor antagonists versus prochlorperazine for control of delayed nausea caused by doxorubicin: a urcc ccop randomised controlled trial. Lancet Oncol. 2005;6:765–72. [PubMed] 28. Srivastava M, Brito–Dellan N, Davis MP, Leach M, Lagman R. Olanzapine as an antiemetic in refractory nausea and vomiting in advanced cancer. J Pain Symptom Manage. 2003;25:578–82. [PubMed] 29. Navari RM, Einhorn LH, Passik SD, et al. A phase ii trial of olanzapine for the prevention of chemotherapy-induced nausea and vomiting: a Hoosier Oncology Group study. Support Care Cancer. 2005;13:529–34. [PubMed] 30. 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Eur J Cancer. 2005 Jun; 41(9):1278-85.
[Eur J Cancer. 2005]JAMA. 2007 Sep 12; 298(10):1196-207.
[JAMA. 2007]Auton Neurosci. 2006 Oct 30; 129(1-2):3-16.
[Auton Neurosci. 2006]Cancer. 2003 Jun 1; 97(11):2880-6.
[Cancer. 2003]Support Care Cancer. 2006 Apr; 14(4):348-53.
[Support Care Cancer. 2006]Support Care Cancer. 2006 Apr; 14(4):348-53.
[Support Care Cancer. 2006]Support Care Cancer. 2004 Jun; 12(6):432-40.
[Support Care Cancer. 2004]Palliat Med. 2000 Jan; 14(1):3-10.
[Palliat Med. 2000]Anticancer Res. 2002 Mar-Apr; 22(2B):1187-92.
[Anticancer Res. 2002]J Clin Oncol. 1999 Jan; 17(1):344-51.
[J Clin Oncol. 1999]Eur J Cancer. 2005 Jun; 41(9):1278-85.
[Eur J Cancer. 2005]J Clin Oncol. 2005 Apr 20; 23(12):2822-30.
[J Clin Oncol. 2005]Cancer. 2000 Dec 1; 89(11):2301-8.
[Cancer. 2000]J Clin Oncol. 1996 Aug; 14(8):2242-9.
[J Clin Oncol. 1996]Expert Opin Drug Metab Toxicol. 2005 Jun; 1(1):143-9.
[Expert Opin Drug Metab Toxicol. 2005]Ann Oncol. 2003 Oct; 14(10):1570-7.
[Ann Oncol. 2003]Cancer. 2003 Dec 1; 98(11):2473-82.
[Cancer. 2003]Ann Oncol. 2006 Sep; 17(9):1441-9.
[Ann Oncol. 2006]J Clin Oncol. 2006 Jun 20; 24(18):2932-47.
[J Clin Oncol. 2006]Eur J Pharmacol. 1993 Nov 2; 249(1):R3-4.
[Eur J Pharmacol. 1993]J Clin Oncol. 2003 Nov 15; 21(22):4112-9.
[J Clin Oncol. 2003]Ann Oncol. 2006 Jun; 17(6):1000-6.
[Ann Oncol. 2006]J Clin Oncol. 2005 Apr 20; 23(12):2822-30.
[J Clin Oncol. 2005]J Clin Oncol. 2005 Apr 20; 23(12):2822-30.
[J Clin Oncol. 2005]Eur J Cancer. 2005 Jun; 41(9):1278-85.
[Eur J Cancer. 2005]Eur J Cancer. 2005 Jun; 41(9):1278-85.
[Eur J Cancer. 2005]J Clin Oncol. 2005 Apr 20; 23(12):2822-30.
[J Clin Oncol. 2005]Cancer Chemother Pharmacol. 2005 Jun; 55(6):609-16.
[Cancer Chemother Pharmacol. 2005]Cancer Chemother Pharmacol. 2007 Feb; 59(3):407-12.
[Cancer Chemother Pharmacol. 2007]Eur J Clin Pharmacol. 2005 Jul; 61(5-6):341-6.
[Eur J Clin Pharmacol. 2005]J Clin Oncol. 2006 Jun 20; 24(18):2932-47.
[J Clin Oncol. 2006]Ann Oncol. 2006 Jan; 17(1):20-8.
[Ann Oncol. 2006]Lancet Oncol. 2005 Oct; 6(10):765-72.
[Lancet Oncol. 2005]J Pain Symptom Manage. 2003 Jun; 25(6):578-82.
[J Pain Symptom Manage. 2003]Support Care Cancer. 2005 Jul; 13(7):529-34.
[Support Care Cancer. 2005]Support Care Cancer. 2007 Nov; 15(11):1285-91.
[Support Care Cancer. 2007]