Page 193 - Risk quantification and modification in older patients with colorectal cancer

This thesis has aimed to investigate which older patients with colorectal cancer (CRC) are at risk of poor surgical outcomes by exploring existing prediction tools and study patient characteristics that could quantify risk and identify patients at a high risk of adverse outcomes (Part I). In addition, interventions were studied designed to modify surgical risk in older patients with CRC and elderly specific outcomes were studied. Finally, the impact of Geriatric Assessment (GA) on treatment decisions in CRC was studied (Part II).
Part I. Risk quantification
Risk prediction models have been developed to provide prognostic information and support treatment decisions. In Chapter 2, existing risk prediction models for adverse outcomes of CRC surgery were systematically reviewed and usefulness and accuracy were assessed to enable preoperative prediction in older patients. A relatively large number of prediction models have been developed, the oldest dating back to 2004. Of 26 models identified, ten predicted mortality and seven anastomotic leakage. None of the models was developed to estimate outcomes for the highly heterogeneous older population nor did these models address outcomes such as quality of life or functional decline. The inclusion of peri-operative predictors limits the use of several models for preoperative decision making. Some models needed further validation because they carried a relatively high risk of bias. Others needed updates because operative risk factors and quality of care may have changed over time, thus affecting a model’s accuracy.
In Chapter 3, we assessed the Identification of Seniors at Risk for Hospitalised Patients (ISAR-HP) and Geriatric 8 (G8) screening tools for their prognostic value for postoperative complications and mortality in a real-life CRC population over the age of 70 years. Patients screened “at risk of frailty” with the ISAR-HP were at increased risk for 30-day complications including cardiopulmonary complications, readmission and six-month mortality. In contrast, patients identified as “at risk of frailty” with the G8 screening tool, did not have a higher risk of poor surgical outcomes However, patients that were at risk of frailty with both screening tools had the highest risk of complications. Therefore, ISAR-HP and G8 combined had the strongest predictive value for complications and mortality.
In Chapter 4, functional dependency, previous falls, undernutrition and risk of delirium were investigated for their prognostic value for 30-day morbidity and
Summary
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