INTRODUCTION: The treatment of rectal cancer has improved, and survival rates today exceed those of colon cancer, but functional impairments and other adverse effects of treatment are common among patients. The impact of treatment on patients' quality of life (QoL) remains unclear. Many of the common QoL instruments are brief and not sufficiently detailed to provide a deeper understanding of the factors that determine QoL. The aim of this study was to explore patients' experiences and long-term QoL in an unselected cohort of patients with rectal cancer.

METHODS: This is a prospective international multicentre study based on a comprehensive, validated questionnaire on functional impairments and QoL administered to an unselected population of 1,500 patients with rectal cancer at diagnosis and after one, two and five years. The clinical characteristics are retrieved from the national quality registers. A total of 14 hospitals in Sweden and Denmark are currently involved in the study. Inclusion is ongoing, and new including hospitals are welcome to join. Full accrual is expected within two years.

CONCLUSION: This study will provide detailed knowledge about the challenges that patients face following diagnosis and treatment of rectal cancer. It will investigate the nature, severity and perceived significance of constraints and symptoms, as well as the impact of a variety of clinical and patient-related factors on QoL. The study will probably identify areas where changes in care routines may improve patients' QoL.

FUNDING: This study was supported by the Swedish Research Council, grant number 2012-1768; the Swedish Cancer Society CAN 2010/593 and CAN 2013/500; the Swedish Society of Medicine; the Gothenburg Medical Society; the Health & Medical Care Committee of the Regional Executive Board, Region Västra Götaland; ALF grant 138751 and 136151, "Agreement concerning research and education of doctors"; Anna-Lisa and Bror Björnsson Foundation; Assar Gabrielsson Foundation; Mary von Sydow Foundation; Ruth and Richard Julin's Foundation and Lion's Cancer Research Foundation of Western Sweden.

TRIAL REGISTRATION: ClinicalTrials.gov (NCT01477229).