Identification of Areas for Improvement in the Management of Bone Metastases in Patients with Neuroendocrine Neoplasms

Background:There is no global consensus on the optimal management of bone metastases (BMs) in neuroendocrine neoplasms (NENs).Objectives:To review current management and outcomes of patients with BMs in NENs, in order to identify areas for improvement.Methods:A retrospective study of all patients with NENs, except Grade 3 lung NENs (April 2002 to March 2018) was conducted. Baseline characteristics, nature of BMs, treatment received and overall survival (OS) were evaluated. Statistical analyses were performed using SPSS version 23.0/STATA v12.Results:Of 1,212 patients, 85 (7%) had BMs; median age 58 years. The majority had a gastro-entero-pancreatic primary (49%,n= 42) followed by lung (25%,n= 21), unknown primary (20%,n= 17), and "others" (6%,n= 5). Two-thirds (n= 57) had G1-2 neuroendocrine tumours, and 41% (n= 35) had functional tumours. Overall, 28% (n= 24) presented with synchronous BMs at first NEN diagnosis, and 55% (n= 47) developed BMs at the same time as other distant metastases. For the subpopulation of patients in whom BMs developed metachronously to other distant metastases (45%,n= 38), median time to development of BMs was 14.0 months. BMs were "widespread" in 61% (n= 52). Although only 22% (n= 19) reported symptoms at initial diagnosis of BMs, most (78%) developed symptoms at some time during the follow-up period (pain/hypercalcaemia 64%, skeletal-related events 20%). BMs were mainly managed with analgesia (44%,n= 37). Radiotherapy and bisphosphonates were used in 34% (n= 29) and 22% (n= 19) respectively. Surgery was rarely performed (2%,n= 2). Median OS from identification of BMs was 31.0, and 18.9 months from development of BMs-related symptoms.Conclusions:In this cohort study, most patients with BMs developed symptoms. The utility of radiotherapy and/or bisphosphonates should be prospectively and systematically explored further for its potential impact on patients' quality of life and survival outcomes.