Impact on Clinical- and Patient-Reported Outcomes Measures of an Organ Preservation-Based Therapeutic Strategy in Locally Advanced Rectal Cancer: The FOREST Project

<b>Background</b>: Locally advanced rectal cancer is traditionally managed with neoadjuvant chemoradiotherapy followed by total mesorectal excision, but radical surgery entails substantial morbidity, including bowel, urinary, and sexual dysfunction as well as permanent stomas. Organ-preserving strategies such as total neoadjuvant therapy (TNT) followed by a watch-and-wait (WW) approach aim to reduce morbidity while maintaining oncologic safety. A recent study from the FOREST cohort confirmed favorable survival outcomes with WW but did not assess the patient-centered impact. <b>Methods</b>: This retrospective observational study included locally advanced rectal cancer patients treated at a tertiary hospital. Following TNT, patients who achieved a complete clinical response entered WW, while others underwent radical surgery (RS). Patient-reported outcomes were assessed using an 18-item questionnaire grouped into domains and transformed to a 0-100 scale according to EORTC scoring methodology. All patients underwent a shared decision-making process. Comparisons between groups used Pearson chi-square tests for clinical and demographics associations and Mann-Whitney U tests for ordinal outcomes. The protocol was integrated into Quirónsalud's value-based healthcare framework. <b>Results</b>: Clinical and demographics characteristics did not differ between WW and RS groups. PROMs favored WW in multiple domains: Symptoms/Complications (87 vs. 66; <i>p</i> < 0.001), Psychosocial adaptation (90 vs. 66; <i>p</i> < 0.001), Mental health (90 vs. 78; <i>p</i> = 0.006), and Global quality of life (80 vs. 67; <i>p</i> = 0.011). Bowel and sexual functions were similar between groups, and Care satisfaction was very high for both. <b>Conclusions</b>: TNT plus WW appears to be oncologically safe and confers significant quality-of-life benefits across several domains. These findings support the theory that WW is a value-based, patient-centered strategy for rectal cancer, and this warrants validation in larger, randomized cohorts.