Quality of life in patients with gastroenteropancreatic tumours: A systematic literature review

Background Gastroenteropancreatic neuroendocrine tumours (GEP-NETs) are slow-growing cancers that arise from diffuse endocrine cells in the gastrointestinal tract (GI-NETs) or the pancreas (P-NETs). They are relatively uncommon, accounting for 2% of all gastrointestinal malignancies. The usual treatment options in advanced GEP-NET patients with metastatic disease include chemotherapy, biological therapies, and peptide receptor radionuclide therapy. Understanding the impact of treatment on GEP-NET patients is paramount given the nature of the disease. Health-related quality of life (HRQoL) is increasingly important as a concept reflecting the patients' perspective in conjunction with the disease presentation, severity and treatment. Aim To conduct a systematic literature review to identify literature reporting HRQoL data in patients with GEP-NETs between January 1985 and November 2019. Methods The PRISMA guiding principles were applied. MEDLINE, Embase and the Cochrane library were searched. Data extracted from the publications included type of study, patient population data (mid-gut/hind-gut/GI-NET/P-NET), sample size, intervention/comparators, HRQoL instruments, average and data spread of overall and sub-scores, and follow-up time for data collection. Results Forty-three publications met the inclusion criteria. The heterogeneous nature of the different study populations was evident; the percentage of female participants ranged between 30%-60%, whilst average age ranged from 53.8 to 67.0 years. Eight studies investigated GI-NET patients only, six studies focused exclusively on P-NET patients and the remaining studies involved both patient populations or did not report the location of the primary tumour. The most commonly used instrument was the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (n = 28) with consistent results across studies; the GI-NET-specific module Quality of Life Questionnaire-GINET21 was used in six of these studies. A number of randomised trials demonstrated no HRQoL changes between active treatment and placebo arms. The Phase III NETTER-1 study provides the best data available for advanced GEP-NET patients; it shows that peptide receptor radionuclide therapy can significantly improve GEP-NET patients' HRQoL. Conclusion HRQoL instruments offer a means to monitor patients' general disease condition, disease progression and their physical and mental well-being. Instruments including the commonly used European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30 and GINET21 lack, however, validation and a defined minimal clinical important difference specifically for GI-NET and P-NET patients.