After all, in other studies that used octreotide doses higher than 8 mg/day and lanreotide doses higher than 10 mg/day [71], no improvement of the SST analogue antitumour effect was observed. No study on the tumour response monitored plasma levels of an SST analogue up to

now, in order to assess that optimal drug therapeutic levels are reached but not exceeded [72]. Clonflicting results have given with regard to tumour regression. Tumour shrinkage was demonstrated in less than 10% of the patients. However, a stabilisation of tumour growth occurs in up to 50% of the patients with neuroendocrine tumours of various locations. Stable disease was observed in 37-45% of the patients with documented tumour progression before SSA therapy (Table 4). The median duration BVD-523 of stabilisation was 26.5 months [26, 73–76]. In a study on a select group of patients with progressive disease, in the 47% of cases was demonstrated www.selleckchem.com/products/bay-57-1293.html a stable disease when treated with a high dose of lanreotide (3-5 g/day) [77]. This result has been confirmed in patients with advanced midgut carcinoids, who had a stabilisation of the disease for 6-24 months in the 75% of cases [78]. One patient with a pancreatic primary tumour, and distant extrahepatic metastases, showed a poor response to treatment in multivariate analysis.

Age, size of the primary tumour, and Ki67 did not influence the response rate to SSA therapy [76]. A stabilisation of the disease was maintain throughout

long-term follow-up in patients who (-)-p-Bromotetramisole Oxalate achieve it after 6 months of treatment; these patients live longer than those unresponsive to therapy [76, 79]. Table 4 Antiproliferative effect of somatostatin analogues in patients with progressive disease. SSA Dosage N CR PR SD PD References Lanreotide 3000 mg/day 22 0 1 7 14 [97] Lanreotide 30 mg/2 weeks 35 0 1 20 14 [90] Octreotide 600 and 1500 mg/day 52 0 0 19 33 [74] Octreotide 1500 and 3000 mg/day 58 0 2 27 29 [26] Lanreotide 15000 mg/day 24 1 1 11 11 [97] Octreotide 600 mg/day 10 0 0 5 5 [73] Octreotide median dose of 250 μg three times daily 34 0 1 17 0 [75] Octreotide LAR 30/ Lanreotide SR 60 mg/28 days 31 0 0 14 4 [76] Total   256 1 6 115 105   Percentage (%)   0.3 2 45 41   SSA, somatostatina analogues; CR, complete remission; PR, partial remission; SD, stable disease; PD, progressive disease. Very recently Rinke et al performed for the first time a placebo-controlled, double-blind, phase IIIB study in 85 patients with well-differentiated metastatic midgut NETs using octreotide LAR 30 mg intramuscularly in monthly intervals. Median time to tumour progression in the octreotide LAR and placebo groups was 14.3 and 6 months, respectively. After 6 months of treatment, stable disease was observed in 66.7% of patients in the octreotide LAR group and 37.2% of patients in the placebo group.