Lenvatinib versus placebo in radioiodine-refractory thyroid cancer

BACKGROUND

Lenvatinib, an oral inhibitor of vascular endothelial growth factor receptors 1, 2, and 3, fibroblast growth factor receptors 1 through 4, platelet-derived growth factor receptor α, RET, and KIT, showed clinical activity in a phase 2 study involving patients with differentiated thyroid cancer that was refractory to radioiodine (iodine-131).

METHODS

In our phase 3, randomized, double-blind, multicenter study involving patients with progressive thyroid cancer that was refractory to iodine-131, we randomly assigned 261 patients to receive lenvatinib (at a daily dose of 24 mg per day in 28-day cycles) and 131 patients to receive placebo. At the time of disease progression, patients in the placebo group could receive open-label lenvatinib. The primary end point was progression-free survival. Secondary end points included the response rate, overall survival, and safety.

RESULTS

The median progression-free survival was 18.3 months in the lenvatinib group and 3.6 months in the placebo group (hazard ratio for progression or death, 0.21; 99% confidence interval, 0.14 to 0.31; P<0.001). A progression-free survival benefit associated with lenvatinib was observed in all prespecified subgroups. The response rate was 64.8% in the lenvatinib group (4 complete responses and 165 partial responses) and 1.5% in the placebo group (P<0.001). The median overall survival was not reached in either group. Treatment-related adverse effects of any grade, which occurred in more than 40% of patients in the lenvatinib group, were hypertension (in 67.8% of the patients), diarrhea (in 59.4%), fatigue or asthenia (in 59.0%), decreased appetite (in 50.2%), decreased weight (in 46.4%), and nausea (in 41.0%). Discontinuations of the study drug because of adverse effects occurred in 37 patients who received lenvatinib (14.2%) and 3 patients who received placebo (2.3%). In the lenvatinib group, 6 of 20 deaths that occurred during the treatment period were considered to be drug-related.

CONCLUSIONS

Lenvatinib, as compared with placebo, was associated with significant improvements in progression-free survival and the response rate among patients with iodine-131-refractory thyroid cancer. Patients who received lenvatinib had more adverse effects. (Funded by Eisai; SELECT ClinicalTrials.gov number, NCT01321554.).

The combination of insulin-like growth factor receptor 1 (IGF1R) antibody cixutumumab and mitotane as a first-line therapy for patients with recurrent/metastatic adrenocortical carcinoma: a multi-institutional NCI-sponsored trial

Adrenocortical carcinoma (ACC) is an aggressive malignancy, which lacks an effective systemic treatment. Abnormal activation of insulin-like growth factor receptor 1 (IGF1R) has been frequently observed. Preclinical studies demonstrated that pharmacological inhibition of IGF1R signaling in ACC has antiproliferative effects. A previous phase I trial with an IGF1R inhibitor has demonstrated biological activity against ACC. The objective of this study is to assess the efficacy of the combination of the IGF1R inhibitor cixutumumab (IMC-A12) in association with mitotane as a first-line treatment for advanced/metastatic ACC. We conducted a multicenter, randomized double-arm phase II trial in patients with irresectable recurrent/metastatic ACC. The original protocol included two treatment groups: IMC-A12 + mitotane and mitotane as a single agent, after an initial single-arm phase for safety evaluation with IMC-A12 + mitotane. IMC-A12 was dosed at 10 mg/kg intravenously every 2 weeks. The starting dose for mitotane was 2 g daily, subsequently adjusted according to serum levels/symptoms. The primary endpoint was progression-free survival (PFS) according to RECIST (Response Evaluation Criteria in Solid Tumors). This study was terminated before the randomization phase due to slow accrual and limited efficacy. Twenty patients (13 males, 7 females) with a median age of 50.2 years (range 21.9-79.6) were enrolled for the single-arm phase. Therapeutic effects were observed in 8/20 patients, including one partial response and seven stable diseases. The median PFS was 6 weeks (range 2.66-48). Toxic events included two grade 4 (hyperglycemia and hyponatremia) and one grade 5 (multiorgan failure). Although the regimen demonstrated activity in some patients, the relatively low therapeutic efficacy precluded further studies with this combination of drugs.

A phase 3, multicenter, double-blind, placebo-controlled trial of lenvatinib (E7080) in patients with 131I-refractory differentiated thyroid cancer (SELECT)

LBA6008

Background: Lenvatinib (LEN) is an oral tyrosine kinase inhibitor of the VEGFR1-3, FGFR1-4, PDGFRβ, RET, and KIT signaling networks. Based on efficacy results of the phase 2 study of patients (pts) with 131I-refractory differentiated thyroid cancer (RR-DTC), this phase 3 Study of (E7080) Lenvatinib in Differentiated Cancer of the Thyroid (SELECT) was developed. Methods: This randomized, double-blind, placebo (PBO)-controlled study enrolled pts with RR-DTC with documented disease progression within 13 months (mo). Pts were stratified by age (≤65, >65 years), region and ≤1 prior VEGFR-targeted therapies and randomized 2:1 to LEN or PBO (24mg/d, 28-d cycle). Upon progression, pts receiving PBO could crossover to open-label LEN. The primary endpoint was PFS assessed by Independent Radiologic Review; secondary endpoints included overall response rate (ORR; complete response [CR] + PR), overall survival (OS) and safety. Results: 392 pts (63.0 years median age; 51.0% male) were randomized. Pts on LEN had a significantly prolonged PFS vs PBO (hazard ratio 0.21, 95% confidence interval [CI] 0.14–0.31; P <.0001); median PFS was LEN: 18.3 mo (95% CI 15.1–not evaluable), PBO: 3.6 mo (95% CI 2.2–3.7). A LEN PFS benefit was observed in all predefined subgroups; median LEN PFS for pts with prior vs no prior VEGF-therapy was 15.1 mo (n=66) and 18.7 mo (n=195), respectively. Rates (n) of CRs were LEN: 1.5% (4), PBO: 0; PRs were LEN: 63.2% (165), PBO: 1.5% (2).Median exposure duration was LEN: 13.8 mo, PBO: 3.9 mo; median time to LEN response was 2.0 mo. Median OS has not been reached; deaths per arm were LEN: 71 (27.2%), PBO: 47 (35.9%). The 5 most common LEN treatment-related adverse events (TRAEs; any grade) were hypertension (68%), diarrhea (59%), appetite decreased (50%), weight loss (46%), nausea (41%). LEN grade ≥3 TRAEs (≥5%) were hypertension (42%), proteinuria (10%), weight loss (10%), diarrhea (8%), appetite decreased (5%). The dose was reduced in 78.5% of pts and discontinued due to adverse events (AEs) in 14.2% of pts. Conclusions: LEN significantly improved PFS compared with PBO in pts with progressive RR-DTC. There were no unexpected toxicities and AEs were manageable. Clinical trial information: NCT01321554.

Cabozantinib in progressive medullary thyroid cancer

PURPOSE

Cabozantinib, a tyrosine kinase inhibitor (TKI) of hepatocyte growth factor receptor (MET), vascular endothelial growth factor receptor 2, and rearranged during transfection (RET), demonstrated clinical activity in patients with medullary thyroid cancer (MTC) in phase I.

PATIENTS AND METHODS

We conducted a double-blind, phase III trial comparing cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomly assigned (2:1) to cabozantinib (140 mg per day) or placebo. The primary end point was progression-free survival (PFS). Additional outcome measures included tumor response rate, overall survival, and safety.

RESULTS

The estimated median PFS was 11.2 months for cabozantinib versus 4.0 months for placebo (hazard ratio, 0.28; 95% CI, 0.19 to 0.40; P < .001). Prolonged PFS with cabozantinib was observed across all subgroups including by age, prior TKI treatment, and RET mutation status (hereditary or sporadic). Response rate was 28% for cabozantinib and 0% for placebo; responses were seen regardless of RET mutation status. Kaplan-Meier estimates of patients alive and progression-free at 1 year are 47.3% for cabozantinib and 7.2% for placebo. Common cabozantinib-associated adverse events included diarrhea, palmar-plantar erythrodysesthesia, decreased weight and appetite, nausea, and fatigue and resulted in dose reductions in 79% and holds in 65% of patients. Adverse events led to treatment discontinuation in 16% of cabozantinib-treated patients and in 8% of placebo-treated patients.

CONCLUSION

Cabozantinib (140 mg per day) achieved a statistically significant improvement of PFS in patients with progressive metastatic MTC and represents an important new treatment option for patients with this rare disease. This dose of cabozantinib was associated with significant but manageable toxicity.

Efatutazone, an oral PPAR-γ agonist, in combination with paclitaxel in anaplastic thyroid cancer: results of a multicenter phase 1 trial

PURPOSE

A phase 1 study was initiated to determine the safety, potential effectiveness, and maximal tolerated dose and recommended phase 2 dose of efatutazone and paclitaxel in anaplastic thyroid cancer.

EXPERIMENTAL DESIGN

Patients received efatutazone (0.15, 0.3, or 0.5 mg) orally twice daily and then paclitaxel every 3 weeks. Patient tolerance and outcomes were assessed, as were serum efatutazone pharmacokinetics.

RESULTS

Ten of 15 patients were women. Median age was 59 years. Seven patients received 0.15 mg of efatutazone, 6 patients received 0.3 mg, and 2 patients received 0.5 mg. One patient receiving 0.3 mg of efatutazone had a partial response from day 69 to day 175; 7 patients attained stable disease. Median times to progression were 48 and 68 days in patients receiving 0.15 mg of efatutazone and 0.3 mg of efatutazone, respectively; corresponding median survival was 98 vs 138 days. The median peak efatutazone blood level was 8.6 ng/mL for 0.15-mg dosing vs 22.0 ng/mL for 0.3-mg twice daily dosing. Ten patients had grade 3 or greater adverse events (Common Terminology Criteria for Adverse Events), with 2 of these (anemia and edema) related to efatutazone. Thirteen events of edema were reported in 8 patients, with 2 of grade 3 or greater. Eight patients had ≥1 serious adverse event, with 1 of these (anemia) attributed to efatutazone and 1 (anaphylactic reaction) related to paclitaxel. The maximal tolerated dose was not achieved. Angiopoietin-like 4 was induced by efatutazone in tissue biopsy samples of 2 patients.

CONCLUSIONS

Efatutazone and paclitaxel in combination were safe and tolerated and had biologic activity.

Dosing patterns for octreotide LAR in neuroendocrine tumor (NET) patients: NCCN NET outcomes database

4142

Background: Among patients (pts) with neuroendocrine histology, 10 mg – 30 mg of octreotide-LAR administered intramuscularly every 4 weeks is FDA-approved for the long term treatment of severe diarrhea and flushing episodes associated with metastatic carcinoid tumors and pancreatic VIPomas. In clinical practice, higher doses and/or more frequent administration is often prescribed for pts who experience refractory symptoms (e.g., flushing and/or diarrhea) on the maximal labeled dose. Methods: National Comprehensive Cancer Network (NCCN) created a comprehensive longitudinal database to characterize pts treated for NETs. This database was queried to identify pts presenting to 7 NCCN institutions, from 2004 to 2010, with a confirmed carcinoid or pancreatic NET (pNET) diagnosis who received octreotide LAR. The primary aim of this analysis was to describe octreotide LAR dosing patterns when beyond label recommendations, clinical characteristics, reasons for dose increase, and maximal dose. Results: Among 1,886 pts in the database, 271 carcinoid and pNET pts received octreotide LAR. 40% of carcinoid pts (n=82) and 23% of pNET pts (n=15) received octreotide LAR above-label dosing, defined by dose and/or frequency greater than 30 mg every 4 weeks. The primary tumor sites among carcinoid pts receiving above label dosing were small bowel (n=40), colorectal (n=4), and unknown (n=34). Reasons for above label dosing among carcinoid pts included uncontrolled symptoms (n=53, 65%), tumor progression (n=21, 25%), high urine 5-HIAA (n=1, 1%) and unknown (n=7, 9%). The most common dose/frequency combinations for carcinoid pts were 40 mg every 4 weeks (32 pts, 39%), 40 mg every 3 weeks (15 pts, 18%), and 30 mg every 2 weeks (14 pts 17%). Among pNET pts, reasons for change included uncontrolled symptoms (n=5, 33%), tumor progression (n=9, 60%), and unknown (n=1, 7%). The most common maximal dose/frequency combinations among pNET pts were 40mg every 4 weeks (n=5, 33%), 30mg every 2 weeks (n=4, 27%), and 60 mg every 4 weeks (n=4, 27). Conclusions: Above label dosing of octreotide LAR is common in NCCN institutions. The primary indication is refractory carcinoid syndrome. Prospective studies are planned to validate this strategy.

Multicenter phase II trial of temsirolimus (TEM) and bevacizumab (BEV) in pancreatic neuroendocrine tumor (PNET)

4032

Background: PNET has long had few effective therapies other than chemotherapy. Placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co primary endpoints were RR and 6-month PFS. Planned enrollment was 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: 55 pts were eligible for response assessment. Confirmed PR was documented in 20 of 55 patients (37%). 44 of 55 (80%) patients were progression-free at 6 months. Of 49 pts evaluable for this endpoint, 12 month PFS is 49%. 15 patients remain on therapy. For evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (18%), hyperglycemia (13%), fatigue (11%). leukopenia (9%), headache (9%), proteinuria (7%), and hypokalemia (7%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 37%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 80% in a population of patients with RECIST criteria progression within 7 months of study entry. Phase III trials of combined VEGF/mTOR inhibition in PNET should be pursued. Clinical trial information: NCT01010126.

Treatment of liver metastases in patients with neuroendocrine tumors: A National Comprehensive Cancer Network analysis

4143

Background: The choice of therapy in patients with hepatic metastases from neuroendocrine tumors is controversial. The purpose of this study was to describe the utilization of liver resection and other locoregional therapies in the management of NET hepatic metastases in NCCN centers. Methods: The National Comprehensive Cancer Network (NCCN) Neuroendocrine Tumor Database tracks longitudinal care for patients treated at seven specialty cancer centers in the U.S. from 2004 to 2010. Patient and tumor characteristics, as well as the use of liver-directed therapy (LDT) in patients with neuroendocrine liver metastases (NELM) were evaluated. Results: Among 907 patients presenting with metastatic disease, 606 patients presenting with newly diagnosed disease or previously diagnosed disease with first distant recurrence of NELM were evaluated. LDT was used during some component of the patient care in only 43% of patients with NELM, the remainder received only systemic or no therapy. LDT varied by extent of disease (p=0.002) with a higher proportion of patients with liver-only disease receiving LDT (45%) compared to those with liver and extrahepatic disease (26%). There was a significant difference in LDT by functional tumor status (Χ2=6.84, p=0.03) and primary site of disease (Χ2=14.95, p=0.001) where a higher proportion of patients with hormonally functional tumors received LDT when compared to non-functional tumors (48% vs 42%) as well as those with primary small bowel carcinoid vs pancreatic NET (56% vs 39%). Among those treated with LDT, 39% underwent surgical resection, 57% intra-arterial therapy (IAT), and 4% ablation alone. Major hepatectomy was performed in 21%, multiple resections in 13%, and resection combined with ablation in 24% of patients receiving surgical therapy. Among the 147 patients treated with IAT, 52% received standard chemoembolization, 23% bland embolization, and 18% yttrium-90 therapy. Conclusions: Even at specialty centers less than half of patients received LDT, among which one-fifth had a hepatic resection. Future studies on this cohort will measure outcomes based on type of LDT.

Efficacy and safety of everolimus in patients with advanced low- or intermediate-grade pancreatic neuroendocrine tumors previously treated with chemotherapy: RADIANT-3 subgroup analysis

224

Background: In the phase 3 RADIANT-3 trial, everolimus (EVE) demonstrated significantly improved median progression-free survival (PFS) versus placebo (PBO) (11.0 vs 4.6 months; HR=0.35, p < 0.0001) in patients (pts) with pancreatic neuroendocrine tumors (pNET) (Yao et al, NEJM, 2011). Here we present a planned exploratory analysis by prior chemotherapy (chemo) use. Methods: Pts with progressive low- or intermediate-grade pNET were prospectively stratified by prior chemo use and randomized (1:1) to EVE 10 mg/d (n = 207) or PBO (n = 203) plus best supportive care. Results: Of the 410 pts, 206 (50%) had received prior chemo and 204 (50%) were chemo naive. Baseline characteristics (age, sex, race, tumor type, histologic grade) and baseline tumor biomarker levels were similar for pts with/without prior chemo. More chemo-naive pts were newly diagnosed (time since initial diagnosis ≤ 6 mo: 50 [25%] vs. 7 [3%] pts with prior chemo). A lower proportion of chemo-naive pts received prior somatostatin therapy (45% vs. 54% prior chemo). EVE significantly prolonged median PFS regardless of prior chemo use (with prior chemo: 11.0 vs. 3.2 months; HR = 0.35, 95% CI 0.25-0.49, p < 0.001; chemo naive: 11.4 vs. 5.4 months; HR = 0.42, 95% CI 0.29-0.60; p < 0.001). Stable disease was the best overall response in 73% of EVE-treated pts irrespective of prior chemo use. The benefit from EVE irrespective of prior chemo was further demonstrated by disease stabilization or minor tumor shrinkage and in the lower incidence of progressive disease in waterfall plots. Safety of EVE was consistent regardless of prior chemo use. The most common drug-related adverse events (chemo vs chemo naive) included rash (53% vs. 52%), stomatitis (52% vs. 56%), diarrhea (41% vs. 52%), and fatigue (37% vs. 51%). Conclusions: This planned subgroup analysis demonstrated the beneficial effects of EVE in pts with pNET regardless of prior chemo use. These findings support the possible first-line use of EVE for pts with pNET.

American Thyroid Association guidelines for management of patients with anaplastic thyroid cancer

BACKGROUND

Anaplastic thyroid cancer (ATC) is a rare but highly lethal form of thyroid cancer. Rapid evaluation and establishment of treatment goals are imperative for optimum patient management and require a multidisciplinary team approach. Here we present guidelines for the management of ATC. The development of these guidelines was supported by the American Thyroid Association (ATA), which requested the authors, members the ATA Taskforce for ATC, to independently develop guidelines for ATC.

METHODS

Relevant literature was reviewed, including serial PubMed searches supplemented with additional articles. The quality and strength of recommendations were adapted from the Clinical Guidelines Committee of the American College of Physicians, which in turn was developed by the Grading of Recommendations Assessment, Development and Evaluation workshop.

RESULTS

The guidelines include the diagnosis, initial evaluation, establishment of treatment goals, approaches to locoregional disease (surgery, radiotherapy, systemic therapy, supportive care during active therapy), approaches to advanced/metastatic disease, palliative care options, surveillance and long-term monitoring, and ethical issues including end of life. The guidelines include 65 recommendations.

CONCLUSIONS

These are the first comprehensive guidelines for ATC and provide recommendations for management of this extremely aggressive malignancy. Patients with stage IVA/IVB resectable disease have the best prognosis, particularly if a multimodal approach (surgery, radiation, systemic therapy) is used, and some stage IVB unresectable patients may respond to aggressive therapy. Patients with stage IVC disease should be considered for a clinical trial or hospice/palliative care, depending upon their preference.

Neuroendocrine tumors

Neuroendocrine tumors comprise a broad family of tumors, the most common of which are carcinoid and pancreatic neuroendocrine tumors. The NCCN Neuroendocrine Tumors Guidelines discuss the diagnosis and management of both sporadic and hereditary neuroendocrine tumors. Most of the recommendations pertain to well-differentiated, low- to intermediate-grade tumors. This updated version of the NCCN Guidelines includes a new section on pathology for diagnosis and reporting and revised recommendations for the surgical management of neuroendocrine tumors of the pancreas.

Radiation pneumonitis following yttrium-90 radioembolization: case report and literature review

Radiation-induced pneumonitis (RP) is a rare complication of radioembolization with yttrium-90 ((90)Y) microspheres. The present report describes a case of RP in a patient with liver metastases from a gastrointestinal stromal tumor after radioembolization with (90)Y glass microspheres. This patient developed clinical, functional, and radiographic findings consistent with RP, with near-complete pulmonary parenchymal recovery and no clinical evidence of relapse or progressive decline in pulmonary function over a 9-month period. As clinical use of radioembolization expands, rare adverse events such as RP may become more frequent. It is essential that interventional radiologists, radiation/medical oncologists, and nuclear medicine physicians recognize this potential complication.

Complete longitudinal analyses of the randomized, placebo-controlled, phase III trial of sunitinib in patients with gastrointestinal stromal tumor following imatinib failure

PURPOSE

To analyze final long-term survival and clinical outcomes from the randomized phase III study of sunitinib in gastrointestinal stromal tumor patients after imatinib failure; to assess correlative angiogenesis biomarkers with patient outcomes.

EXPERIMENTAL DESIGN

Blinded sunitinib or placebo was given daily on a 4-week-on/2-week-off treatment schedule. Placebo-assigned patients could cross over to sunitinib at disease progression/study unblinding. Overall survival (OS) was analyzed using conventional statistical methods and the rank-preserving structural failure time (RPSFT) method to explore cross-over impact. Circulating levels of angiogenesis biomarkers were analyzed.

RESULTS

In total, 243 patients were randomized to receive sunitinib and 118 to placebo, 103 of whom crossed over to open-label sunitinib. Conventional statistical analysis showed that OS converged in the sunitinib and placebo arms (median 72.7 vs. 64.9 weeks; HR, 0.876; P = 0.306) as expected, given the cross-over design. RPSFT analysis estimated median OS for placebo of 39.0 weeks (HR, 0.505, 95% CI, 0.262-1.134; P = 0.306). No new safety concerns emerged with extended sunitinib treatment. No consistent associations were found between the pharmacodynamics of angiogenesis-related plasma proteins during sunitinib treatment and clinical outcome.

CONCLUSIONS

The cross-over design provided evidence of sunitinib clinical benefit based on prolonged time to tumor progression during the double-blind phase of this trial. As expected, following cross-over, there was no statistical difference in OS. RPSFT analysis modeled the absence of cross-over, estimating a substantial sunitinib OS benefit relative to placebo. Long-term sunitinib treatment was tolerated without new adverse events.

Lenvatinib treatment of advanced RAI-refractory differentiated thyroid cancer (DTC): Cytokine and angiogenic factor (CAF) profiling in combination with tumor genetic analysis to identify markers associated with response

5518

Background: Lenvatinib is an oral tyrosine kinase inhibitor targeting VEGFR1-3, FGFR1-4, RET, KIT and PDGFRβ. In a phase II study of lenvatinib, 58 patients (pts) with DTC were enrolled and a response rate of 50% was observed (Sherman, ASCO 2011). Methods: Pts received lenvatinib at a starting dose of 24 mg oral once daily in 28-day cycles. Serum was collected at baseline (BL), on day 8 and on day 36 and concentrations of 47 CAFs were measured using multiplex bead arrays and enzyme-linked immunosorbent assay (ELISA). 33 genes (443 mutations) were examined in archival tumor tissues (n=25). Association of baseline CAF, changes in CAF levels upon treatment and gene mutation status with treatment outcomes was investigated. Results: Combination of low baseline VEGF and ANG-2 (p=0.02 and HR=0.386) correlated with longer PFS. Both baseline and changes in CAF levels demonstrated an association with gene mutation status. High baseline levels of VEGF were observed in pts with wild type RAS and BRAF (p=0.035) whereas high baseline sTIE-2 levels associated with RAS mutation (p=0.023). Supporting pre-clinical mouse xenograft tumor model developed using ANG2-overexpressing human thyroid cancer cell line FTC-286 demonstrated reduced sensitivity to lenvatinib treatment. Increased levels of IL-10 and FGF-2 8-day post-treatment (8d post-tx) significantly associated with RAS (N- or K-) and BRAF mutation. Combination of gene mutation status with baseline CAF levels provided better prediction of longer PFS compared to gene mutation alone. Hierarchical clustering modeling using changes in CAF levels 8d post-tx with tumor shrinkage identified a set of CAFs that could predict two categories of lenvatinib response: longer PFS and greater tumor shrinkage or longer PFS in the absence of significant tumor shrinkage. Conclusions: CAF profiling identified potential predictive biomarkers of lenvatinib treatment outcomes in DTC. Combination of RAS and BRAF mutation with baseline VEGF and ANG-2 or treatment-associated changes in FGF-2 and IL-10 level correlated with lenvatinib treatment response.

A phase II trial of the multitargeted kinase inhibitor lenvatinib (E7080) in advanced medullary thyroid cancer (MTC)

5591

Background: Lenvatinib is an oral tyrosine kinase inhibitor targeting VEGFR1-3, FGFR1-4, RET, KIT and PDGFRβ. In phase I studies of lenvatinib partial responses (PR) were observed in thyroid as well as melanoma, endometrial, and renal cancers. Methods: Patients (pts) with unresectable MTC and disease progression demonstrated by RECIST during the prior 12 months were enrolled. Pts may have received prior VEGFR targeted therapy. Pts were treated with a starting dose of lenvatinib 24 mg once daily in 28 day cycles until disease progression or development of unmanageable toxicities. Primary end point was Response Rate (RR) by RECIST. Tumor genetic analysis and circulating cytokine and angiogenic factors (CAF) analysis were performed. Results: 59 pts were enrolled (med age: 52; Male: 63%;) and are evaluable for response. 54% of pts required dose reduction for management of toxicity, and 22% were withdrawn from therapy due to toxicity. The most common treatment-related adverse events were proteinuria 58% (Gr3: 2%), diarrhea 56% (Gr3: 5%), hypertension 48% (Gr3: 7%), fatigue 44% (Gr3: 5%), decreased appetite 41% (Gr3: 5%), nausea 34% (Gr3: 0), and weight decreased 32% (Gr3: 3%). No Gr4 events were reported for these event categories. Confirmed PRs were observed in 21pts (RR: 36%, 95% CI: 24-49) based on independent imaging review (IIR) and 29 pts (RR: 49%, 95% CI: 36-62) based on investigator assessment. For pts who received prior VEGFR-directed treatment (n=26) RR=35% (IIR); with no prior VEGFR-directed treatment (n=33) RR=36 % (IIR). Median PFS by IRR is 9.0 mo (95% CI: 7.0-) (based on minimum 8 mo. f/u, 46% events observed). There was no clear difference in treatment response between RET-mutant (RET-mu) and RET-wild type (RET-wt) patients. Low baseline levels of ANG2, sTie-2, HGF and IL-8 were associated with greater tumor shrinkage and prolonged PFS whereas high baseline levels of VEGF and sVEGFR3 were associated with greater tumor shrinkage. Conclusions: Lenvatinib administered orally at a dose of 24 mg once daily to patients with MTC is associated with manageable toxicity and a RR of 36%, identifying lenvatinib as a promising new potential therapeutic agent for treating patients affected with this disease.

Baseline demographics of neuroendocrine tumor patients presenting to seven National Comprehensive Cancer Network (NCCN) institutions: Development of a multi-institutional outcomes database

e14551

Background: Diagnostic strategies, management paradigms, and clinical outcomes of patients with neuroendocrine tumors (NETs) are diverse and poorly characterized. The National Comprehensive Cancer Network (NCCN) created a comprehensive database to characterize patients treated for NETs at seven participating institutions. Preliminary results from the database are reported. Methods: Member IRB approval was obtained to identify patients at least 18 years of age presenting to each of seven NCCN institutions between 2004 and 2007 with pathologically confirmed newly or previously diagnosed NETs via hospital medical records. Eligible patients included those with carcinoid (any site); goblet cell or adenocarcinoid; composite carcinoid; poorly differentiated gastrointestinal small cell tumor; pancreatic NET; NET of unknown primary site; pheochromocytoma; and paraganglioma. Baseline demographic characteristics were summarized for this analysis. Results: Among the 2,798 patients identified with a NET diagnosis, patients most frequently presented with carcinoid tumor (53%), pancreatic NET (26%) and NET of unknown primary site (8%). Median age at diagnosis was 56 (SD=14). Fifty-three percent of patients were female. Most (86%) were Caucasian and 8% were African American. Thirty percent of patients were diagnosed with NET before presenting to the NCCN. Among these, the median time between initial NET diagnosis and presentation to the NCCN was 2 years (SD=6). Significant differences in provider specialty referral patterns were observed between institutions. The institutional point of entry for the majority of patients was medical oncology (institutional range: 17-93%) or surgery (institutional range: 3-62%). Conclusions: The baseline demographic characteristics of NET patients in this new database are consistent with those previously reported in population-based registries. The database will provide a valuable resource for further exploration of patterns of diagnosis, treatment, and consistency with established guidelines, as well as clinical outcomes in patients with this condition.

Description of initial treatment for newly diagnosed metastatic carcinoid (cNET) and pancreatic neuroendocrine (pNET) patients

e14542

Background: There is limited descriptive information regarding treatment (tx) patterns for NET from clinic practice data. The primary aim of this analysis was to describe initial tx among NET pts as a first step in understanding tx patterns for NET. Methods: The National Comprehensive Cancer Network (NCCN) Oncology Outcomes Database was queried to identify newly diagnosed pts presenting to 7 NCCN institutions with a confirmed metastatic cNET or pNET diagnosis in 2004 or 2005. Pts with a minimum of 5 years of follow up or confirmed death were included in the analysis. Pt demographics, clinical characteristics, initial tx, and 5-year survival were described. Results: Among 187 cNET pts, 52% were male, median age at diagnosis was 58, and 51% alive. Approximately 58% had a known primary tumor; 65% of which were in the small bowel. Most cNET pts (85%) presented with symptoms, 33% had carcinoid syndrome. Initial tx included surgical therapy in 43%, drug therapy in 41%, and other therapies in 16%. The majority (82%) had imaging prior to treatment, among which 79% had a CT scan and 35% had somatostatin receptor scintigraphy (SRS). The most frequent biomarker test was for CGA (performed in 64 pts, elevated in 53). Of 76 cNET pts receiving initial drug therapy, 82% were treated with a somatostatin analog (SA); others received chemotherapy or targeted therapy. Kaplan-Meier (K-M) curves indicated a 5-year survival of 62% and 56% among pts receiving surgery or drug therapy as initial tx, respectively. Among 104 pNET pts, 61% were male, median age at diagnosis was 54, and 41% alive. Approximately 82% presented with symptoms among which 25% were hormone related. Among the 84% of pts imaged prior to treatment, CT scan was most common (79%) and 38% had SRS. The most common initial tx among pNET pts was drug therapy (56%); 60% received a SA; 31% received chemotherapy. Only 25% underwent surgery as initial tx. K-M curves indicated a 5-year survival of 63% among surgical pts in contrast to 31% for pts whose initial tx was drug therapy. Conclusions: Initial tx among the majority of pts was either surgery or drug therapy. Among cNET and pNET pts receiving drug therapy, 82% (n=62) and 60% (n=35) respectively, received an SA.

Multicenter phase II trial of temsirolimus (TEM) and bevacizumab (BEV) in pancreatic neuroendocrine tumor (PNET): Results of a planned interim efficacy analysis

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Background: PNET has long had few effective therapies other than chemotherapy. Recent placebo-controlled phase III trials of the mTOR inhibitor everolimus and the VEGF/ PDGF receptor inhibitor sunitinib noted improved progression-free survival (PFS). However, objective response rates (RR) with these agents are still <10%. Preclinical studies suggest enhanced anti-tumor effects with combined mTOR and VEGF targeted therapy. Methods: We conducted a phase II trial of the mTOR inhibitor TEM (25 mg IV q week) and the VEGF-A monoclonal antibody BEV (10 mg/kg IV q 2 weeks) in patients (pts) with well or moderately differentiated PNET and progressive disease by RECIST within 7 months of study entry. Co-primary endpoints were RR and 6-month PFS. Planned enrollment is 50 patients, with interim analysis for futility after the first 25 evaluable pts. Pts had no prior mTOR or VEGF targeted agents, ECOG PS 0-1, and adequate hematologic and organ function. Continued octreotide was allowed, but not required. Prior interferon, embolization, and ≤ 2 chemotherapy regimens were allowed. Results: Confirmed PR was documented in 13 of the first 25 (52%) evaluable patients. 21 of 25 (84%) patients were progression-free at 6 months. Both endpoints exceeded the protocol-defined criteria to continue enrollment. For 36 evaluable patients, the most common grade 3-4 adverse events attributed to therapy were hypertension (14%), leukopenia (11%), lymphopenia (11%), hyperglycemia (11%), mucositis (8%), hypokalemia (8%), and fatigue (8%). Conclusions: The combination of TEM/BEV has substantial activity in a multi-center phase II trial with RR of 52%, well in excess of single targeted agents in PNET. 6-month PFS was a notable 84% in a population of patients with RECIST criteria progression within 7 months of study entry. Accrual is ongoing.

An international, double-blind, randomized, placebo-controlled phase III trial (EXAM) of cabozantinib (XL184) in medullary thyroid carcinoma (MTC) patients (pts) with documented RECIST progression at baseline

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Background: MTC arises from parafollicular cells of the thyroid gland, accounts for 5-8% of thyroid cancers and represents an unmet medical need. Cabozantinib (cabo) is an oral inhibitor of MET, VEGFR2, and RET. We conducted a phase III study of cabo vs placebo (P) in pts with progressive, unresectable, locally advanced or metastatic MTC. Methods: Eligible pts were required to have documented RECIST progression within 14 months of screening. The primary efficacy measure was progression-free survival (PFS) as assessed by an independent review facility (IRF) using RECIST. Secondary efficacy measures included objective response rate (ORR) and overall survival (OS). The study has 90% power to detect a 75% increase in PFS and 80% power to detect a 50% increase in OS. Tumor assessments occurred every 12 weeks. Crossover between treatment arms was not allowed. Results: Between Sept 2008 and Feb 2011, 330 pts (median age 55 yrs; 67% male; 96% measureable disease; RET mutation status: pos 48%; neg 12%; unknown 39%; prior TKI exposure: yes 21%, no 78%, unknown 2%) were randomized 2:1 to cabo (140 mg free base [175 mg salt form] qd; n=219) or P (n=111). The planned primary PFS analysis included events through the date of the 138th event. As of 15June2011, 44.7% of pts on cabo and 13.5% on P were still receiving study treatment. Statistically significant PFS prolongation of 7.2 mo was observed; median PFS for cabo was 11.2 mo vs 4.0 mo for P (HR 0.28, 95% CI 0.19-0.40, p<0.0001). PFS results favored the cabo group across subset analyses including RET status and prior TKI use. ORR was 28% for cabo vs 0% for P (p<0.0001). An interim analysis of OS (44% of the 217 required events) did not show a difference between cabo and P. The most frequent grade ≥3 adverse events (cabo vs P) were diarrhea (15.9 vs 1.8%), palmar-plantar erythrodysesthesia (12.6 vs 0%), fatigue (9.3 vs 2.8%), hypocalcemia (9.3 vs 0%), and hypertension (7.9 vs 0%). Conclusions: This phase III study met its primary objective of demonstrating substantial PFS prolongation with cabo vs. P in a patient population with MTC and documented progressive disease in need of therapeutic intervention.

Prevalence of functional tumors in neuroendocrine carcinoma: An analysis from the NCCN NET database

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Background: Neuroendocrine tumors (NETs) are increasing in incidence and prevalence. Identification and treatment of specific clinical NET syndromes are established, yet there is uncertainty regarding the prevalence of NET with hormone-related symptoms versus nonfunctional tumors. Methods: The National Comprehensive Cancer Network (NCCN) created a comprehensive database to characterize patients (pts) treated for NETs. This database was queried to identify pts presenting to 7 NCCN institutions with a confirmed NET diagnosis: including carcinoid (cNET), pancreatic NET (pNET), NET not otherwise specified (NOS), and pheochromocytoma (PCC) between 2004 and 2010. The primary aim of this analysis was to describe demographic and clinical characteristics of NET pts by functional (fxn) status at diagnosis (dx). Results: Among 1244 NET pts, 26% (n=327) had an fxn tumor. Carcinoid syndrome (CS) occurred in 28% of cNET pts. The most common primary tumor sites among CS pts were small bowel (69%) and unknown (15%). Prevalence of hormonal syndrome (HS) among pNET pts was 22%, 24% among NOS pts and 37% among PCC pts. The majority of CS pts (74%), pNET HS pts (67%), and NOS HS pts (91%) had distant disease at dx, in contrast to 31% of PCC HS patients. Among CS pts with a known histologic grade, 91% were well differentiated (G1). Similarly, 86% of pNET HS and 67% of NOS HS pts with a known histologic grade had G1 NETs. The most common symptoms at dx among pts with CS included abdominal cramping (53%), change in bowel habits (48%), and flushing (40%). Among those tested, 85% of CS pts had a positive 5-HIAA test at dx. Among pNET HS pts, the most common symptoms present at dx were abdominal cramping (39%) and change in bowel habits (46%). The most common symptoms present at dx among NOS HS pts were abdominal cramping (35%), change in bowel habits (47%) and flushing (38%). Conclusions: Prevalence of CS in this NCCN database (28%) was slightly higher than the 10% previously reported in the literature. In contrast, the prevalence of HS among pNET pts (22%) was lower than previously reported. Approximately one quarter of cNET pts without metastatic disease had CS, warranting further analysis as CS most often occurs in the presence of liver metastasis.