Quality of life as subjective experience: Reframing of perception in patients with colon cancer undergoing radical resection with or without adjuvantchemotherapy

Purpose and background: We examined whether patients with colon cancer unde rgoing surgery with or without adjuvant chemotherapy change the internal st andards on which they base their quality-of-life (QL) estimation, and, if t hey do so, whether this reframing alters interpretation of QL findings. The se questions were addressed within a randomized clinical trial of the Swiss Group for Clinical Cancer Research (SAKK 40/93). Patients and methods: After radical resection of adenocarcinoma of the colo n (pT(1-4)pN>M-0(0) and pT(3-4)pN(0)M(0)) and perioperative chemotherapy, p atients were randomized to three treatment arms: observation only (A), 5-FU 450 mg/m(2) plus Levamisol (B), or 5-FU 600 mg/m(2) (C). QL was measured b y linear analogue self-assessment indicators. Patients estimated their pre- surgery QL both before surgery and retrospectively thereafter, and their pr e-adjuvant QL both at the beginning of randomly assigned chemotherapy or ob servation and retrospectively about two months later. Thereafter, current Q L was assessed. Paired t-tests were used to test the hypotheses of no chang e. Results: Overall, 187 patients with at least one pair of corresponding ques tionnaires were analyzed. Patients estimated their pre-surgery QL after sur gery significantly lower than before and their pre-adjuvant QL under treatm ent or observation also lower than at the beginning. In the adjuvant phase, in contradiction to our hypothesis, chemotherapy had almost no impact on t hese changes attributed to reframing. Conventionally assessed changes indic ated an improvement in QL. Patients with treatment C reported less improvem ent in functional performance than those with B or those under observation (P = 0.04). Patients with treatment B indicated a greater worsening in naus ea/vomiting than those with C, whereas patients with observation only showe d an improvement (P = 0.0009). After adjustment of current QL scores under treatment or observation to patients' retrospective estimation, the treatme nt effects were diluted but the overall improvement was substantially ampli fied in most QL indicators. Conclusions: Patients with colon cancer substantially reframe their percept ion in estimating QL both under radical resection and under adjuvant chemot herapy or observation. This effect is an integral part of patients' adaptat ion to disease and treatment. An understanding of this phenomenon is of par ticular relevance for patient care. Its role in evaluating QL endpoints in clinical trials needs further investigation.