Endocrine Abstracts

Background and aims: Immediate release somatostatin analogues (SAs) have routinely been administered to test tolerability prior to commencing long-acting SAs, though there is limited evidence to support this process. We aim to examine this practice at our centre.

Methods: Patients who received SA therapy for a neuro endocrine tumours (NET) between December 2012 and December 2014 were identified. Records were used to identify; start date, duration of test-dosing and side effects experienced during test dosing. Data was collected on the initial long-acting SA dose and subsequent side effects experienced during treatment.

Results: Sixty-nine patients, 40 male and 29 female, were identified during the defined period. 29 had functional tumours, 40 non-functional. 24 received in-patient test-doses with three immediate release octreotide doses over 24 hours; centre practice from 2012 to early 2013. 45 received test-dosing as a day-case, with a single immediate release dose of octreotide; centre practice from late 2013 onwards. Eight patients, 4 as inpatient and 4 as day-case, experienced side effects during test dosing, including nausea (3), steatorrhea (3) and possible bradycardia (1). No patients had symptoms severe enough to prevent starting a long acting SA. 42 (61%) patients experienced side effects from the long-acting SA. Only 4 (9.5%) of these experienced side effects during test dosing, 2 as in-patient and 2 as a day-case. There was a low correlation between test-dosing and overall side-effect profile.

Conclusions: There is lack of evidence to support ongoing test dosing for patients commencing long-acting SA. There is also a lack of correlation between side-effects from test dosing and overall side-effects on long-acting SA. We have now changed practice at our centre, commencing our patients on long-acting SA without a test-dose of immediate release octreotide. Further collaborative work is planned to review this approach in a cross-centre audit.