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Supplemental Figure: Mean plasma concentrations of vandetanib.

Supplemental Tables 1-3. Supplementary Table 1: Correlations in the vandetanib/RT/TMZ arm between best radiographic responses with pre-treatment and on-treatment changes in blood biomarkers. Supplementary Table 2: Correlations in the vandetanib/RT/TMZ arm between overall survival with pre-treatment and on-treatment changes in blood biomarkers. Supplementary Table 3: Comparison of PFS or OS by log-rank p-value based on tissue biomarker analysis

Purpose: Although antiangiogenic therapy for high-grade glioma (HGG) is promising, responses are not durable. Correlative clinical studies suggest that the SDF-1α/CXCR4 axis may mediate resistance to VEGFR inhibition. Preclinical data have demonstrated that plerixafor (a reversible CXCR4 inhibitor) could inhibit glioma progression after anti-VEGF pathway inhibition. We conducted a phase I study to determine the safety of plerixafor and bevacizumab in recurrent HGG. Patients and Methods: Part 1 enrolled 23 patients with a 3 × 3 dose escalation design to a maximum planned dose of plerixafor 320 μg/kg subcutaneously on days 1 to 21 and bevacizumab 10 mg/kg intravenously on days 1 and 15 of each 28-day cycle. Cerebrospinal fluid (CSF) and plasma samples were obtained for pharmacokinetic analyses. Plasma and cellular biomarkers were evaluated before and after treatment. Part 2 enrolled 3 patients and was a surgical study to determine plerixafor's penetration in tumor tissue. Results: In Part 1, no dose-limiting toxicities were seen at the maximum planned dose of plerixafor + bevacizumab. Treatment was well tolerated. After plerixafor 320 μg/kg treatment, the average CSF drug concentration was 26.8 ± 19.6 ng/mL. Plerixafor concentration in resected tumor tissue from patients pretreated with plerixafor was 10 to 12 μg/g. Circulating biomarker data indicated that plerixafor + bevacizumab induces rapid and persistent increases in plasma SDF-1α and placental growth factor. Progression-free survival correlated with pretreatment plasma soluble mesenchymal–epithelial transition receptor and sVEGFR1, and overall survival with the change during treatment in CD34+ progenitor/stem cells and CD8 T cells. Conclusions: Plerixafor + bevacizumab was well tolerated in HGG patients. Plerixafor distributed to both the CSF and brain tumor tissue, and treatment was associated with biomarker changes consistent with VEGF and CXCR4 inhibition. Clin Cancer Res; 24(19); 4643–9. ©2018 AACR.

BACKGROUND: Fatigue is a common symptom among glioma patients and affects quality of life. Armodafinil, a wakefulness-promoting medication, benefits patients with fatigue of various causes. This study evaluates the effects of armodafinil on fatigue in glioma patients undergoing radiation therapy (RT). METHODS: Eligibility criteria included age ≥ 18; KPS ≥ 60; grade 2-4 glioma undergoing RT to a total dose of 50-60 Gy with or without chemotherapy. Patients were randomized 1:1 to armodafinil or placebo. Fatigue assessments were made at baseline, Day 22, Day 43, and Day 56 with the FACIT-F Fatigue Scale, FACT-G, Brief Fatigue Inventory (BFI), and Cancer Fatigue Scale (CFS). The primary aim was to detect a difference in the 42-day change in FACIT-F fatigue subscale scores between the two groups using a 2-sample Wilcoxon statistic. Secondary outcomes include a 42-day change in FACT-G, CFS, and BFI. RESULTS: In the armodafinil arm, median age was 56 (25-79), median KPS was 90 (70-100), 58.5% with grade 4 glioma, 34.2% with grade 3 glioma, 2.4% with grade 2 glioma. In the placebo arm, median age was 54 (19-78), median KPS was 90 (70-100), 47.8% with grade 4 glioma, 30.8% with grade 3 glioma, 10.3% with grade 2 glioma. The median 42-day change in the FACIT-F fatigue subscale scores in the armodafinil arm was 1 (range -40 to 26) and in the placebo arm was -5.50 (range -65 to 28) with Wilcoxon p-value of 0.14. Toxicity was rare and similar between arms. CONCLUSIONS: Treatment with armodafinil is well tolerated in glioma patients undergoing RT. Preliminary results do not demonstrate statistically significant reduction in fatigue between groups. Updated results will be presented.

Purpose: Vandetanib, a tyrosine kinase inhibitor of KDR (VEGFR2), EGFR, and RET, may enhance sensitivity to chemotherapy and radiation. We conducted a randomized, noncomparative, phase II study of radiation (RT) and temozolomide with or without vandetanib in patients with newly diagnosed glioblastoma (GBM). Experimental Design: We planned to randomize a total of 114 newly diagnosed GBM patients in a ratio of 2:1 to standard RT and temozolomide with (76 patients) or without (38 patients) vandetanib 100 mg daily. Patients with age ≥ 18 years, Karnofsky performance status (KPS) ≥ 60, and not on enzyme-inducing antiepileptics were eligible. Primary endpoint was median overall survival (OS) from the date of randomization. Secondary endpoints included median progression-free survival (PFS), 12-month PFS, and safety. Correlative studies included pharmacokinetics as well as tissue and serum biomarker analysis. Results: The study was terminated early for futility based on the results of an interim analysis. We enrolled 106 patients (36 in the RT/temozolomide arm and 70 in the vandetanib/RT/temozolomide arm). Median OS was 15.9 months [95% confidence interval (CI), 11.0–22.5 months] in the RT/temozolomide arm and 16.6 months (95% CI, 14.9–20.1 months) in the vandetanib/RT/temozolomide (log-rank P = 0.75). Conclusions: The addition of vandetanib at a dose of 100 mg daily to standard chemoradiation in patients with newly diagnosed GBM or gliosarcoma was associated with potential pharmacodynamic biomarker changes and was reasonably well tolerated. However, the regimen did not significantly prolong OS compared with the parallel control arm, leading to early termination of the study. Clin Cancer Res; 21(16); 3610–8. ©2015 AACR.

Objective: A subset of meningiomas recur after surgery and radiation therapy, but no medical therapy for recurrent meningioma has proven effective. Methods: Pasireotide LAR is a long-acting somatostatin analog that may inhibit meningioma growth. This was a phase II trial in patients with histologically confirmed recurrent or progressive meningioma designed to evaluate whether pasireotide LAR prolongs progression-free survival at 6 months (PFS6). Patients were stratified by histology (atypical [World Health Organization grade 2] and malignant [grade 3] meningiomas in cohort A and benign [grade 3] in cohort B). Results: Eighteen patients were accrued in cohort A and 16 in cohort B. Cohort A had median age 59 years, median Karnofsky performance status 80, 17 (94%) had previous radiation therapy, and 11 (61%) showed high octreotide uptake. Cohort B had median age 52 years, median Karnofsky performance status 90, 11 (69%) had previous radiation therapy, and 12 (75%) showed high octreotide uptake. There were no radiographic responses to pasireotide LAR therapy in either cohort. Twelve patients (67%) in cohort A and 13 (81%) in cohort B achieved stable disease. In cohort A, PFS6 was 17% and median PFS 15 weeks (95% confidence interval: 8–20). In cohort B, PFS6 was 50% and median PFS 26 weeks (12–43). Treatment was well tolerated. Octreotide uptake and insulin-like growth factor–1 levels did not predict outcome. Expression of somatostatin receptor 3 predicted favorable PFS and overall survival. Conclusions: Pasireotide LAR has limited activity in recurrent meningiomas. The finding that somatostatin receptor 3 is associated with favorable outcomes warrants further investigation. Classification of evidence: This study provides Class IV evidence that in patients with recurrent or progressive meningioma, pasireotide LAR does not significantly increase the proportion of patients with PFS at 6 months.

High-grade gliomas, which include glioblastomas (GBMs) and anaplastic gliomas (AGs), are the most common malignant primary brain tumors in adults1 and are associated with poor survival despite maximal surgery, radiation, and chemotherapy.2–4 Bevacizumab, a humanized monoclonal antibody against vascular endothelial growth factor (VEGF), is frequently used to treat recurrent high-grade glioma (HGG). Bevacizumab monotherapy received accelerated approval for recurrent GBM by the United States Food and Drug Administration in 2009 on the basis of phase II clinical trials demonstrating response rates of 20%–26%, 6-month progression-free survival (PFS6) rates of 29%–42.6%, and median overall survival (OS) of 7.1–9.2 months.5,6 Phase II studies in recurrent AG suggest that bevacizumab plus irinotecan also has activity in this patient population with response rates of 55%–66% and PFS6 rates of 56%–61%.7,8 However, responses to bevacizumab are not durable, and some patients fail to benefit.9 Panobinostat is a potent, small-molecule inhibitor of classes I, II, and IV histone deacetylases (HDACs) with greater potency than vorinostat.10 HDAC inhibitors, including panobinostat, may inhibit angiogenesis by reducing VEGF secretion and modulating the expression of other VEGF family members via inhibition of HIF-1α.11–14 In addition, the SDF-1α/CXCR4 pathway has been implicated in bevacizumab resistance,15–17 and panobinostat depletes CXCR4 levels and signaling.18 A phase I study of panobinostat in combination with bevacizumab for recurrent HGG suggested that oral panobinostat 30 mg 3 times per week, every other week, can be safely combined with bevacizumab 10 mg/kg every other week.19 We conducted a multicenter, phase II trial of panobinostat in combination with bevacizumab in patients with recurrent GBM. We also examined the same combination of agents in patients with recurrent AG as an exploratory arm.

Although anti‐angiogenic therapy for high-grade glioma (HGG) is promising, responses are not durable. The SDF-1/CXCR4 axis may help mediate resistance to VEGFR inhibition. Plerixafor is a reversible CXCR4 inhibitor that has demonstrated growth inhibition in glioblastoma xenografts. We conducted a Phase I study to determine the safety and tolerability of plerixafor in combination with bevacizumab in recurrent HGG. Part 1 of the study enrolled 23 patients and was a 3 x 3 dose escalation design to a maximum planned dose level of plerixafor 320 µg/kg on Days 1–21 and bevacizumab 10 mg/kg on Days 1 and 15 of each 28 day cycle. Dose-limiting toxicities (DLTs) were determined during the initial 4 weeks of therapy. CSF and concomitant plasma samples were obtained to determine pharmacokinetic (PK) data. Part 2 of the study enrolled 3 patients and was a surgical study to determine if plerixafor penetrates tumor tissue. Patients were pre-treated with plerixafor 320 µg/kg for 5–9 days before surgery. For all 26 patients enrolled on study, the median age is 59 (23–72), median KPS 90 (70–100), 11 women (42.3%). In Part 1, no DLTs were seen at the maximum planned dose level of plerixafor + bevacizumb. Treatment was well tolerated with one grade 3 hypophosphatemia and one grade 3 rectal fistula. Serum PK data on plerixafor in this study compares well with historical PK data. At a plerixafor dose of 320 µg/kg, the average CSF concentration was 26.8 ng/mL (SD +/- 19.6). Circulating biomarker data suggests that plerixafor + bevacizumab induces rapid and persistent increases in plasma SDF1 and PlGF. Plerixafor concentration in resected tumor tissue from patients pre-treated with plerixafor was 1000–1200 ng/mL. Combination treatment with bevacizumab and plerixafor was well tolerated in HGG patients. Plerixafor distributes to both the CSF and brain tumor tissue.

Although anti-angiogenic therapy for high-grade glioma is promising, responses are not durable. The SDF-1/CXCR4 axis may help mediate resistance to VEGFR inhibition. Plerixafor is a reversible CXCR4 inhibitor that has demonstrated growth inhibition in glioblastoma xenografts. We conducted a Phase I study to determine the safety and tolerability of plerixafor in combination with bevacizumab in patients with recurrent HGG. A 3 x 3 dose escalation design to a maximum planned dose level of plerixafor 320 µg/kg on Days 1-21 and bevacizumab 10 mg/kg on Days 1 and 15 of each 28 day cycle was used. DLTs were determined during the initial 4 weeks of therapy and included drug-related Grade ≥ 3 non-hematologic toxicities and Grade ≥ 4 hematologic toxicities. Part 1 of the study has been completed with a total of 23 patients enrolled with the following characteristics: median age 58 (23-72), median KPS 90 (70-100), 11 women (47.8%). One DLT (grade 3 rectal fistula) was seen at a dose level of plerixafor 240 µg/kg + bevacizumab and the cohort was expanded. Because no further DLTs were seen at the 240 µg/kg dose level, the maximum planned dose level of plerixafor 320 µg/kg + bevacizumb opened and a total of 12 patients were treated with no DLTs. Treatment was well tolerated with one grade 3 hypophosphatemia and one grade 3 rectal fistula. Preliminary pharmacokinetic data on plerixafor from the first two cohorts compares well with historical PK data. Combination treatment with bevacizumab and plerixafor was well tolerated in the studied HGG patients. No DLTs were encountered at the maximum planned dose level. The study will now expand to a surgical cohort to examine tumor tissue penetration as well as a separate non-surgical cohort with patients treated with continuous daily dosing of plerixafor 320 µg/kg and bevacizumab. Updated results will be presented.

Bevacizumab is frequently used to treat recurrent high-grade gliomas, but responses are generally not durable. Panobinostat is a histone deacetylase inhibitor with anti-neoplastic and anti-angiogenic effects in glioma models and may work synergistically with bevacizumab. We conducted a multicenter phase II trial of panobinostat in combination with bevacizumab. Two cohorts were enrolled: one with recurrent glioblastoma (GBM) as the primary study and one with recurrent anaplastic glioma (AG) as the exploratory study. Patients received oral panobinostat 30 mg 3 x per week, every other week, in combination with bevacizumab 10 mg/kg every other week. The primary endpoint was PFS6 in the GBM cohort and the study was powered to discriminate between a 35% and 55% PFS6 rate (85% power at an alpha level of 0.07). At planned interim analysis, 13 of the first 21 patients accrued to the GBM cohort had progressed within 6 months of initiating study treatment. The GBM cohort did not meet criteria for continued accrual and was closed early. In the GBM cohort, PFS6 rate was 30.4%, median PFS 5 months, median OS 9 months. Accrual in the AG cohort continued to completion and a total of 15 patients were enrolled. In the AG cohort, PFS6 rate was 46.7%, median PFS 7 months, median OS 17 months. The most common grade 3 or 4 toxicities in the GBM arm were hypophosphatemia (12.5%), thrombocytopenia (12.5%), lymphopenia (8.3%), neutropenia (8.3%), and ALT elevation (8.3%). In the AG arm, the most common toxicities were thrombocytopenia (20.0%) and hypophosphatemia (13.3%). Although reasonably well-tolerated, this phase II study of panobinostat and bevacizumab in recurrent GBM did not meet criteria for continued accrual and the GBM cohort of the study was closed. In the recurrent AG cohort, the PFS6 rate was similar to historical controls. Updated data will be presented.

Bevacizumab is FDA-approved for patients with recurrent GBM. However, the median duration of response is only 4 months. Potential mechanisms of resistance include upregulated FGF signaling and increased PDGF-mediated pericyte coverage. Nintedanib is an oral, small-molecule tyrosine kinase inhibitor of PDGFR α/β, FGFR 1-3, and VEGFR 1-3 that may overcome resistance to anti-VEGF therapy. This was a two-stage phase II trial in adults with first or second recurrence of GBM, stratified by prior bevacizumab therapy (ClinicalTrials.gov number NCT01380782; 1199.94). The primary endpoint was PFS6 in the bevacizumab-naive arm (Arm A) and PFS3 in the post-bevacizumab arm (Arm B). Up to 10 anaplastic glioma (AG) patients were accrued to each arm in exploratory cohorts. Twenty-two patients enrolled in Arm A and 14 in Arm B. Arm A included 12 GBMs (55 %), 13 patients with one prior regimen (59 %), and median age 54 years (range 28-75). Arm B included 10 GBMs (71 %), one patient with one prior regimen (7 %), and median age 52 years (range 32-70). Median KPS overall was 90 (range 60-100). There were no responses. In Arm A (GBM only), PFS6 was 0 %, median PFS 28 days (95 % CI 27-83), and median OS 6.9 months (3.7-8.1). In Arm B (GBM only), PFS3 was 0 %, median PFS 28 days (22-28), and median OS 2.6 months (1.0-6.9). Among AG patients in each arm, PFS6 was 0 %. Treatment was well tolerated. In conclusion, nintedanib is not active against recurrent high-grade glioma, regardless of prior bevacizumab therapy.

Among patients with glioblastoma (GBM) who progress on standard temozolomide, the optimal therapy is unknown. Resistance to temozolomide is partially mediated by O(6)-methylguanine-DNA methyltransferase (MGMT). Because MGMT may be depleted by prolonged temozolomide administration, dose-intense schedules may overcome resistance.This was a multicenter, phase 2, single-arm study of temozolomide (75-100 mg/m(2)/day) for 21 days of each 28-day cycle. Patients had GBM in first recurrence after standard therapy. The primary end point was 6-month progression-free survival (PFS6).Fifty-eight participants were accrued, 3 of whom were ineligible for analysis; one withdrew before response assessment. There were 33 men (61%), with a median age of 57 years (range, 25-79 years) and a median Karnofsky performance score of 90 (range, 60-100). Of 47 patients with MGMT methylation results, 36 (65%) had methylated tumors. There were 7 (13%) partial responses, and PFS6 was only 11%. Response and PFS did not depend on MGMT status; MSH2, MLH1, or ERCC1 expression; the number of prior temozolomide cycles; or the time off temozolomide. Treatment was well tolerated, with limited grade 3 neutropenia (n = 2) or thrombocytopenia (n = 2).Dose-intense temozolomide on this schedule is safe in recurrent GBM. However, efficacy is marginal and predictive biomarkers are needed.

TPS2080 Background: Although anti-angiogenic therapy for high-grade glioma is promising, responses are not durable. The SDF-1/CXCR4 axis may help mediate resistance to VEGFR inhibition. Plerixafor ...

2020 Background: Bevacizumab is frequently used to treat recurrent high-grade gliomas, but responses are generally not durable. Panobinostat is a histone deacetylase inhibitor with anti-neoplastic ...

2027 Background: No medical therapy for recurrent meningioma has proven effective, yet a subset of these tumors recur after surgery and radiation. A pilot study of sustained-release somatostatin yi...

2053 Background: Bevacizumab is FDA-approved for patients with recurrent GBM. However, the median duration of response is only 4 months. Potential mechanisms of resistance include upregulated FGF s...

2013 Background: Bevacizumab is frequently used to treat recurrent GBM, but responses are generally not durable. Panobinostat is a histone deacetylase inhibitor with anti-neoplastic and anti-angiogenic effects in GBM and may work synergistically with bevacizumab. We conducted a multicenter phase I/II trial of panobinostat in combination with bevacizumab in patients with recurrent GBM. Methods: In the phase II trial, patients with recurrent GBM were treated with oral panobinostat 30 mg three times per week, every other week, in combination with bevacizumab 10 mg/kg every other week. The primary endpoint was 6-month progression-free survival (PFS6) and the study was powered to discriminate between a 35% and 55% PFS6 rate (85% power at an alpha level of 0.07). A planned interim analysis specified suspension of accrual and careful data review if 12 or more of the first 21 patients accrued to the study progress within 6 months of initiating treatment. Patients with recurrent GBM enrolled in the phase I study at the maximum tolerated dose (which is the phase II dose) were eligible for inclusion in the interim analysis. Results: Thirteen of the first 21 patients accrued to the GBM arm of the study had progressed within 6 months of initiating study treatment. The study was closed to further accrual and a planned interim analysis was performed. Median age was 53 (range 22-66) and median KPS was 80% (60%-100%). PFS6 rate was 33.9% [95% CI 12.8, 56.5), median was PFS 5 months [95% CI 3 months, NR], and median OS was 342 days [95% CI 203 days, NR]. Five patients (23.8%) achieved partial responses. Conclusions: Although reasonably well-tolerated, this phase I/II study of panobinostat and bevacizumab in recurrent GBM did not meet criteria for continued accrual and the study was closed. Updated outcome and safety data will be presented at the meeting. Study Supported by: Novartis and Genentech Clinical trial information: NCT00859222.

Objective: We conducted a randomized phase II study of vandetanib in patients with newly-diagnosed GBM in combination with radiation (RT) and temozolomide (TMZ). Background EGFR and VEGFR signaling have been implicated in the development and growth of GBM. In addition, angiogenesis inhibitors may enhance radiation sensitivity. Vandetanib is an inhibitor of VEGFR-2 and EGFR tyrosine kinase activities. Design/Methods: We planned to randomize a total of 114 newly-diagnosed GBM patients in a ratio of 1:2 to Arm A: RT/TMZ or Arm B: vandetanib 100 mg daily + RT/TMZ. All pts received RT (60 Gy) and concurrent TMZ 75 mg/m 2 daily, followed by adjuvant TMZ for up to 12 cycles (150-200 mg/m 2 on days 1-5 of each 28 day cycle). Pts with age ≥ 18, Karnofsky performance status (KPS) ≥ 60, and not on enzyme-inducing antiepileptics were eligible. Primary endpoint was overall survival (OS) from the date of randomization. Secondary endpoints included median progression-free survival (PFS) and safety. Results: We enrolled 106 pts (36 in Arm A, 70 in Arm B) with median age 59 yrs (range: 23-83) and median KPS 90 (range: 60-100). Most frequent Gr ≥ 3 AEs in the vandetanib arm were lymphopenia (20%), thrombosis (12.5%), transaminitis (8%) and leukopenia (5%). Preliminary median OS is 487 days with 95% CI (350, NR) in Arm A and 503 days with 95% CI (451, 634) in Arm B. Median PFS is 141 days with 95% CI (104. 252) in Arm A and 127 days with 95% CI (93. 165) in Arm B. Due to an unplanned interim analysis demonstrating no survival difference, enrollment was terminated early and the study was closed. Conclusions: Although reasonably well-tolerated, the addition of vandetanib to standard chemoradiation in newly-diagnosed GBM may not significantly prolong OS compared to the parallel control arm. Updated efficacy and toxicity data will be presented. Supported by: AstraZeneca. Disclosure: Dr. Lee has received personal compensation for activities with Norvartis and Genentech as an advisory board member.Dr. Lee has received personal compensation in an editorial capacity for UpToDate, Inc. Dr. Batchelor has received personal compensation for activities with Roche Diagnostics Corporation, Genentech, Inc., Merck & Co. Inc., and Millennium. Dr. Batchelor has received personal compensation in an editorial capacity for UpToDate Inc. Dr. Batchelor has received research support from Pfizer Inc, AstraZeneca Pharmaceuticals and Millennium. Dr. Kaley has nothing to disclose. Dr. Schiff has received personal compensation for activities with Novocure and Genentech. Dr. Schiff has received research support from Exelixis. Dr. Lassman has received personal compensation for activities with Schering-Plough Corp., ImClone Systems, Genentech, Inc., Eisai Inc., Cephalon, Inc., Physicians Education Resource, The Robert Michael Educational Institute, and Medical Communications Media.Dr. Lassman has received research support from Keryx Biopharmaceuticals, Genentech, and Schering Plough Corp. Dr. Wong has received research support from AstraZeneca Pharmaceuticals, Exelixis, Novartis and NovoCure as a researcher. Dr. Mikkelsen has received personal compensation for activities with Merck and Roche. Dr. Purow has nothing to disclose. Dr. Drappatz has nothing to disclose. Dr. Norden has nothing to disclose. Dr. Beroukhim has received personal compensation for activities with Novartis as a consultant. Dr. Beroukhim holds stock and/or stock options in AstraZeneca, which sponsored research in which Dr. Beroukhim was involved as an investigator. Dr. Beroukhim holds stock and/or stock options in Baxter, CareFusion, Edwards Lifesciences, and Cardinal Health. Dr. Beroukhim has received research support from Novartis. Dr. Weiss has received personal compensation for activities with a consulting firm as RT expert. Dr. Weiss has received research support from Aposence. Dr. Alexander has nothing to disclose. Dr. McCluskey has nothing to disclose. Dr. Gerard has nothing to disclose. Dr. Teulings has nothing to disclose. Dr. Smith has nothing to disclose. Dr. Muzikansky has nothing to disclose. Dr. Wen has received personal compensation for activities with Merck & Co., and Novartis as consutant and/or speaker. Dr. Wen has received personal compensation in an editorial capacity for UptoDate. Dr. Wen has received research support from Amgen Inc, AstraZeneca Pharmaceuticals, Eisai Inc, Exelixis, Genentech, Inc., Medimmune, Merck & Co., Novartis, Sanofi-Aventis Pharmaceuticals and Vascular Biogenics.

2069 Background: EGFR and VEGFR signaling have been implicated in the development and growth of GBM. Simultaneous inhibition of both pathways may be more effective than inhibiting a single pathway....

2040 Background: Patients with recurrent or progressive meningiomas who have exhausted surgical and radiation options have limited remaining treatment choices. Somatostatin receptors are expressed ...