Age and Comorbidity Considerations Related to Radiotherapy and Chemotherapy Administration

Sixty percent of incident cancer cases and 70% of mortality occurs in individuals over the age of 65 years, this increase may correlate with increased comorbidity burden making treatment decisions more difficult to call. age is a known risk factor for the development of cancer. “Comorbidity in cancer patients refers to other concurrent patient illnesses”. Elderly patients and/or patients with significant comorbidity burden are routinely excluded from randomized controlled trials in order not to potentially affect any postitive results of whatever is being tested. Therefore, clinical trial results may still have limited external validity for many elderly patients. Janssen-Heijnen et al (cited in article) observed survival decrements related to age and comorbidities, with comorbidity having a minimal role in patients with highly aggressive tumors. Other important relevant relationships have been described in the medical literature: 1 Age, comorbidity, functional impairment, and cancer site are all independent contributors to survival time. 2 Comorbidity burden can have a differential impact on survival in cancer populations with different baseline survival rates. 3 Comorbidity and functional status are separate entities within the context of elderly patients and need to be measured individually. 4 Type/intensity of cancer treatment and their related complication patterns can be impacted by both age and comorbidity status. 5 Observed population-based treatment adaptations owing to age and/or comorbidity considerations depend on the cancer site involved. 6 Frequently observed adaptive therapies include less use of surgery when alternative approaches are available (chemoradiation, radiation alone, chemotherapy alone, hormonal therapy), less use of adjuvant radiation and/or chemotherapy after surgery, and increased use of observation strategies where available. 7 Age and comorbidity burden have impacts on both health-related quality of life13 and symptom burden.27 In a population of cancer survivors, younger age was associated with higher symptom burden than older patients. Radiothearpy- the long duration of radical radiation therapy (>5 weeks) and geographic considerations (patient travel time away from home) can play a critical role in patient selection of palliative or best supportive care treatment where a more radical course would be generally indicated. radical or palliative radiotherapy can be a tolerable treatment for elderly patients when comorbidities functional status is assessed and integrated into the treatment plan. Chemo- factors affecting pharmacokinetics/dynamics in increasing age can have important effects on chemotherapy dosing and tolerance include decreased renal function, decreased volume of distribution, decreased liver cytochrome P450 function, decreased gastrointestinal absorption, and decreased bone marrow reserve. A complete patient assessment should include documentation of the patients' chronologic age, estimated physiological age, presence and severity of comorbidities, contraindications to radiotherapy (and chemotherapy), and performance/functional status. “medical optimization of baseline comorbidities before treatment should be considered to optimize patient treatment tolerability and to reduce comorbidity impact and mortality.” Ref- http://www.sciencedirect.com/science/article/pii/S1053429612000471