The Challenges of Treating Cancer in Older Patients – How Effective Are Clinical Trials in Developing Unique Treatments?

European Oncology, 2008;4(1):94-6

Abstract:

Demographic changes in developing countries are leading to a rapid increase in the absolute number of the elderly population.1 The management of elderly patients with cancer currently represents a major challenge for the medical community.2 An elderly patient is arbitrarily defined as someone aged 65 years and over. It has been suggested that those aged over 65 should be divided into younger-old (age 65–74 years), mid-old (age 75–84 years) and old-old (age exceeding 85 years). The age of 75 years and older is usually set as the cut-off point for more vigilant attention, because the incidence of age-related physical changes increases sharply between 70 and 75 years.3

Citation European Oncology, 2008;4(1):94-6

In industrialised countries, the fastest growing segment of the population is composed of individuals aged 65 years or over,4 and this demographic group is predicted to increase by 13.3% by 2010 and by 53.2% by 2020.5 The over-75-year-old group will triple by 2030, and the over-85-year-old group will double in the same period.6 By 2050, 21% of the older population is expected to be aged 80 years or older.3

Over the last century, life expectancy has been steadily rising. In 2003, the US Vital Statistics estimated median life expectancy for 65-year-old men to be 17 years; for 70-year-olds it was 13 years, for 75-year-olds it was nine years and for 80-year-olds it was seven years.7 This expansion in life expectancy, coupled with increased incidence of cancer, is having a profound effect on the prevalence of cancer.

The risk of developing cancer increases with ageing.1 Over 50% of all new cancer cases are diagnosed in people aged 65 years or older, and over 60% of all cancer deaths occur in this group of the population.8 Despite this, cancer diagnosis and treatment in the elderly has been under-researched, with elderly patients frequently being excluded from clinical trials.5 Only a small subset of geriatric patients are being entered into clinical trials. Thus, elderly patients are still managed on the basis of assumptions based on a younger population group.1 Elderly patients with cancer should be assessed and treated differently from younger patients, as age-related physical changes affect the biology of cancer but also the physiology of elderly patients. These should be factored in while planning treatment.1,9,10 Hence, older patients cannot be managed in the same way as their younger counterparts due to concomitant and possibly multiple medical problems.11

Ageing is a complex, heterogeneous and highly individualised process. A person’s age alone does not always predict his or her physiological decline. This is due in part to the effect of co-morbidity on ageing.12 Patients of the same chronological age can differ greatly in physiological age and other aspects of ageing.9 Time of onset is affected by multiple factors including diet, race, sex, physical activity, habits and hormonal effect.1,26 The hallmark of senescence is decreased functional reserve of individual organs and the reduced ability of these organs to cope with the challenge.1 Ageing is associated with a decrease in gastrointestinal motility, splanchnic blood flow, secretion of digestive enzymes and mucosal atrophy, which can result in a reduced drug absorption rate.12–14

References:
  1. Ramesh HSJ, Pope D, Gennari D, Audisio RAA, Optimising surgical management of elderly cancer patients, World J Surg Oncol, 2005;3:17.
  2. Terret C, Management and geriatric assessment of cancer in the elderly, Expert Rev Anticancer Ther, 2004;4:469–75.
  3. Surbone A, Kagawa-Singer M, Terret C, Baider L, on behalf of the SIOG Task Force on Cultural Competence in the Elderly, Ann Oncol, 2007;18:633–8.
  4. Townsley C, Pond GR, Peloza B, et al., Analysis of treatment practices for elderly cancer patients in Ontario, Canada, J Clin Oncol, 2005;23:3802–10.
  5. Pope D, Ramesh H, Gennari R, et al., Pre-operative Assessment of Cancer in the Elderly (PACE): a comprehensive assessment of underlying characteristics of elderly cancer patients prior to elective surgery, Surgical Oncology, 2007;15:189–97.
  6. Lichtman M, Guidelines for the treatment of elderly cancer patients, Journal of the Moffitt Cancer Center, 2003;10:445–53.
  7. Scardino PT, Surgery in elderly cancer patients, Nat Clin Pract Neurol, 2006;3:397.
  8. Wedding U, Pientka L, Hoffken K, Quality-of-life in elderly patients with cancer: a short review, Eur J Cancer, 2007;43: 2203.
  9. Ershler WB, Cancer: a disease of the elderly, J Support Oncol, 2003;1(Suppl. 2):5–10.
  10. Balducci L, Beghè C, Cancer and age in the USA, Crit Rev Oncol Hematol, 2001;37:137–45.
  11. Terret C, A challenge for the future, European Oncology Review, 2005.
  12. Lichtman SM, Treating elderly cancer patients: what you need to know about their physiology and specific medical needs, Community Oncology, 2006;3:730–34.
  13. Yuen GJ, Altered pharmacokinetics in the elderly, Clin Geriatr Med, 1990;6:257–67.
  14. Baker SD, Grochow LB, Pharmacology of cancer chemotherapy in the older person, Clin Geriatr Med, 1997;13:169–83.
  15. Boggs DR, Patrene KR, Hematopoiesis and aging III: anemia and a blunted erythropoietic response to hemorrhage in aged mice, Am J Hematol, 1985;19:327–38.
  16. Baraldi-Junkins CA, Beck AC, Rothstein G, Hematopoiesis and cytokines: relevance to cancer and aging, Hematol Oncol Clin North Am, 2000;14:45–61, viii.
  17. Balducci L, Geriatric oncology, Crit Rev Oncol Hematol, 2003;46:211–20.
  18. Jörgensen T, Johansson S, Kennerfalk A, et al., Prescription drug use diagnoses and healthcare utilization among the elderly, Ann Pharmacother, 2001;35:1004–9.
  19. Hanlon JT, Fillenbaum GG, Ruby C, et al., Epidemiology of over-the counter drug use in community dwelling elderly: United States perspective, Drugs Aging 2001;18:123–31 (Rieseman C, Antidepressant drug interactions and the cytochrome P450 system:a critical appraisal, Pharmacotherapy, 1995;15:84–99).
  20. Repetto L, Audisio RA, Elderly patients have become the leading drug consumers: it’s high time to properly evaluate new drugs within the real targeted population, JCO, 2006;24:e62–3.
  21. Chalaire D, Participation of elderly patients in clinical trials: looking beyond age, Oncolog, 2004;49.
  22. Food and Drug Administration, Guideline for the study of drugs likely to be used in the elderly. Available at: www.fda.gov/cder/guidance/old040fn.pdf
  23. Kaluzny A, Brawley O, Garson-Angert D, et al., Assuring access to state-of-the-art care for U.S. minority populations: the first 2 years of Minority-Based Community Clinical Oncology Program, J Natl Cancer Inst, 1993;85:1945–50.
  24. Tejeda HA, Green SB, Trimble EL, et al., Representation of African-Americans, Hispanics, and whites in National Cancer Institute treatment trials, J Natl Cancer Inst,1996;88:812–16.
  25. Joseph R, Viewpoints and concerns of a clinical trial participant, Cancer, 1994;74:2692–3.
  26. Hutchins LF, Unger JM, Crowley JJ, et al., Underrepresentation of patients 65 years of age or older in cancer-treatment trials, N Engl J Med, 1999;341: 2061–7.
  27. Townsley CA, Selby R, Siu LL, Systematic review of barriers to the recruitment of older patients with cancer onto clinical trials, J Clin Oncol, 2005;23:3112–124.
  28. Audisio RA, Pope D, Ramesh HS, et al., Shall we operate? Preoperative assessment in elderly cancer patients (PACE) can help, A SIOG surgical task force prospective study, Crit Rev Oncol Hematol, 2008;65:156–63.
  29. Bayer A, Tadd W, Unjustified exclusion of elderly people from studies submitted to research ethics committee for approval: descriptive study, BMJ, 2000;321:992–3.
  30. Bugeja G, Kumar A, Banerjee AK, Exclusion of elderly people from clinical research: a descriptive study of published reports, BMJ, 1997;315:1059.
  31. Repetto L, Venturino A, Vercelli M, et al., Performance status and comorbidity in elderly cancer patients compared with young patients with neoplasia and elderly patients without neoplastic conditions, Cancer, 1998;82:760–65.
  32. Fennessy M, Bates T, MacRae K, et al., Late follow-up of a randomized trial of surgery plus tamoxifen versus tamoxifen alone in women aged over 70 years with operable breast cancer, Br J Surg, 2004;91:699–704.
  33. O’Connell JB, Maggard MA, Ko CY, Cancer-directed surgery for localized disease: decreased use in the elderly, Ann Surg Oncol, 2004;11:962–9.
  34. Tournoux C, Katashian S, Chevret S, et al., Factors influencing inclusion of patients with malignancies in clinical trials: a review, Cancer, 2006;106:258–70.
  35. Lara PN, Paterniti DA, Chiechi C, et al., Evaluation of factors affecting awareness of and willingness to participate in cancer clinical trials, J Clin Oncol, 2005; 23:9282–9.
  36. Terret C, Zulian GB, Naiem A, et al., Multidisciplinary approach to the geriatric oncology patient, J Clin Oncol, 2007;25:1876–81.
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