Report on short-term side effects of treatments with 177Lu-octreotate in combination with capecitabine in seven patients with gastroenteropancreatic neuroendocrine tumours

Purpose Treatment with the radiolabelled somatostatin analogue ¹⁷⁷Lu-octreotate results in tumour remission in 47% of patients with gastroenteropancreatic neuroendocrine tumours. Adding capecitabine to ¹⁷⁷Lu-octreotate, as a radio-sensitiser, may enhance these anti-tumour effects. We now present the short-term toxicity profile of this novel combination. Methods Seven patients were treated with 7.4 GBq ¹⁷⁷Lu-octreotate and capecitabine (1650 mg/m² per day) for 2 weeks with an intended number of four cycles. Toxicity, and especially haematological and renal parameters, were monitored on a weekly basis for the first two cycles and 4 and 6 weeks after subsequent cycles. Results None of the patients had hand-foot syndrome. One patient had grade 1 stomatitis occurring after one of four cycles. Grade 3 or 4 leukopenia or neutropenia did not occur. One patient had grade 3 anaemia, but none had grade 4 anaemia. One patient had grade 2 thrombocytopenia after the fourth cycle, and one had grade 3 thrombocytopenia. Grade 4 thrombocytopenia did not occur. No significant changes in serum creatinine levels were observed. None of the patients had symptoms of cardiac ischaemia. Conclusions Treatment with the combination of ¹⁷⁷Lu-octreotate and capecitabine was feasible and safe considering acute and subacute side effects. We therefore started a randomised, controlled clinical trial to compare this combination with ¹⁷⁷Lu-octreotate as single agent with regard to anti-tumour effects and side effects.