Improved Prognosis in Midgut Carcinoid patients by treating raised circulating Neurokinin A (NKA)
JES Ardill1, BJ Johnston1, GB Turner1, A McGinty2 & DR McCance1
Midgut Carcinoid disease (MGC) is uncommon, occurring in approximately 1.4 per 100,000 of the population per year. MGC has an unpredictable disease progression varying from rapid and aggressive to slow and indolent. For this reason it is not appropriate to treat all patients according to the same schedule. As some treatments are not without risk, it is important to identify those patients selected for these options at an appropriate stage of disease.
In a retrospective study (N=150) we have shown previously that circulating NKA is the best independent indicator of poor prognosis in MGC. Patients presenting with NKA >50 pmol/l showed a 3 year survival of 10% in contrast to 65% for those presenting with NKA <50 pmol/l. In addition the data from this study has shown that the most recent NKA is the most accurate prognostic indicator.
In the majority of MGC patients circulating NKA concentrations may be reduced by use of somatostatin analogue therapy or by intervention with more aggressive treatments.
We now report preliminary results from a prospective study of patients presenting at the regional centre for neuroendocrine tumours in Northern Ireland, where we have treated consecutive, newly diagnosed MGC patients. All have been treated to address disease bulk, symptom control and to maintain NKA concentrations <50 pmol/l. Thirty patients have been included in this study to date. Mean circulating NKA was 94.5 pmol/l at presentation and was reduced to 28.5 pmol/l at six months. Six of thirty patients (20%) required additional treatments to control a rising NKA concentration within one year of diagnosis.
Preliminary results indicate that MGC patients have a longer survival than expected from the previous study. Patients presenting with high NKA (>50 pmol/l) who are treated with a more aggressive regime to maintain circulating NKA, <50 pmol/l survive significantly longer than previously reported in our retrospective study.