Appendiceal Goblet Cell Carcinoids: Management Considerations from a Reference Peritoneal Tumour Service Centre and ENETS Centre of Excellence

BACKGROUND: Appendix goblet cell carcinoids (GCCs) are known to share histological features of adenocarcinoma and neuroendocrine tumours. Due to their low incidence, quality evidence is lacking for management of these patients. METHODS: We performed a single-centre retrospective study of patients with confirmed diagnosis of appendiceal GCC (1996-2014). Patients were divided into curative intent (CI) and palliative intent (PI) cohorts. Our primary end-point was overall survival (OS). RESULTS: Seventy-four patients were eligible; 76% were treated with CI (surgery only (36%), Cytoreductive Surgery (CRS) and Hyperthermic Intra-peritoneal Chemotherapy (HIPEC) (36%), adjuvant chemotherapy (20%) and combination of CRS and HIPEC followed by adjuvant chemotherapy (9%)); 23% had advanced stage-disease amenable to palliative treatment (chemotherapy or supportive care) only. Completion right hemicolectomy, performed in 64% of the CI cohort, did not impact on relapse rate or disease-free survival. FOLFOX chemotherapy was used in both adjuvant and palliative settings; safety was as expected and we observed a high rate (60%) of disease control in the palliative cohort. The estimated median OS (all patients), disease-free (CI patients) and progression-free survivals (PI patients) were 52.1 (95% CI 29.4-90.3), 75.9 (26.6-not reached) and 5.3 (0.6-5.7) months, respectively. Age and stage were independent factors associated with OS in the multivariable analysis. Tang classification showed a trend for impact on OS. No benefit from specific adjuvant approach was identified; however selection bias for treatment approach was observed. CONCLUSION: Prospective trials are needed to define optimal approaches in GCC. All GCC patients should be managed by specialized centres due to their esoteric behaviour; we provide management considerations based on our experience and conclusions.