Durable response to lenvatinib in progressive, therapy-refractory, metastatic paraganglioma

Metastatic pheochromocytomas and paragangliomas: where are we?

Pheochromocytomas and paragangliomas (PPGLs) can metastasize in approximately 15-20% of cases. This review discusses the available evidence on the biology and treatment of metastatic PPGLs. Chemotherapy is the first-line treatment option for this evolving and symptomatic disease. In patients with high MIBG uptake and positive PETGa-68, radiometabolic treatment may be considered. The efficacy of sunitinib has been shown in observational studies, and pembrolizumab has been evaluated in phase II clinical studies, while other agents investigated in this setting are anti-angiogenic drugs cabozantinib, dovitinib, axitinib and lenvatinib. As these agents' efficacy and safety data, alone or in combination, are scant and based on few treated patients, enrollment in clinical trials is mandatory. Future therapeutic options may be represented by DNA repair system inhibitors (such as olaparib), HIF2 inhibitors and immunotherapy.

Lenvatinib as a Therapeutic Option in Unresectable Metastatic Pheochromocytoma and Paragangliomas

Context

Metastatic pheochromocytomas and paragangliomas (mPPGL) are rare vascular neuroendocrine tumors that highly express vascular growth factors. Systemic treatment options in cases of unresectable multi-site disease are limited. Multikinase inhibitors, that inhibit angiogenesis, such as lenvatinib, have proven effective in several other malignancies, and may be a viable option for mPPGL.

Objective

To evaluate the efficacy of lenvatinib as salvage therapy in mPPGLs.

Design

Retrospective analysis of mPPGL patients who received lenvatinib from 2015-2020.

Setting

Tertiary referral center

Patients

Patients ≥ 18 years with mPPGL who were treated with lenvatinib were included.

Intervention

Patients were started on lenvatinib 20 mg daily and dose was adjusted according to tolerance or disease progression.

Results

11 patients were included. Median treatment duration was 14.7 months (95% CI: 2.3-NE). Treatment was discontinued due to disease progression, adverse events, or death. Overall survival at 12 months was 80.8% (95% CI: 42.3-94.9%) but its median was not reached. Median progression free survival was 14.7 months (CI 95%: 1.7-NE). Among the 8 patients with measurable disease, overall response rate was 63% as 5/8 experienced a partial response and 3/8 had stable disease. Worsening hypertension and anemia were the most common adverse events (AE).

Conclusions

Lenvatinib may be a viable treatment option for mPPGL, though at the potential risk of worsening hypertension. Larger, multi-center studies are needed to better characterize treatment efficacy.

Metastatic pheochromocytoma and paraganglioma: Management of endocrine manifestations, surgery and ablative procedures, and systemic therapies

Metastatic pheochromocytomas and paragangliomas (MPPGs) are rare neuroendocrine tumors. Most patients present with advanced disease that is associated with manifestations of catecholamine release. Surgical resection of the primary tumor and ablative therapies of metastases-whenever possible-may improve clinical outcomes and, perhaps, lengthen the patient's overall survival. Significant steps in understanding the genetic alterations linked to MPPGs and scientific progress made on cancers that share a similar pathogenesis are leading to the recognition of potential systemic therapeutic options. Data derived from clinical trials evaluating targeted therapies such as tyrosine kinase inhibitors, radiopharmaceuticals, immunotherapy, and combinations of these will likely improve the outcomes of patients with advanced and progressive MPPGs. Exemplary of this success is the recent approval in the United States of the high-specific-activity iodine¹³¹ meta-iodine-benzylguanidine (MIBG) for patients with unresectable and progressive MPPGs that express the noradrenaline transporter. This review will discuss the therapeutic approaches for patients with MPPGs.

Phase II trial of pazopanib in advanced/progressive malignant pheochromocytoma and paraganglioma

INTRODUCTION

Pheochromocytomas and paragangliomas (Pheo/PGL) are rare, vascular, sometimes malignant endocrine tumors. Case reports indicate the activity of vascular endothelium growth factor receptor-targeted kinase inhibitors in these cancers.

OBJECTIVES

To assess the antitumor activity and tolerability of pazopanib in progressive malignant Pheo/PGL.

PATIENTS AND METHODS

This multicenter Phase II trial (MC107C) enrolled individuals  ≥18 years old with disease progression ≤ 6 months prior to registration, Eastern Cooperative Oncology Group PS 0-2, and measurable disease (response evaluation criteria in solid tumors 1.0). Pazopanib was administered in 28-day cycles, with the regimen ultimately being as follows: cycle 1: 400 mg daily on days 1-14, cycle 2: 800 mg daily on days 1-14, and then cycle 2 + : 800 mg daily on all days.

RESULTS

The study was halted due to poor accrual. Seven patients were enrolled (05/2011-11/2014). One patient withdrew consent prior to treatment, leaving six evaluable patients. Treatment was discontinued, due to the following reasons: disease progression (4); withdrawal (1); and grade 4 (Takotsubo) cardiomyopathy (1). The median number of cycles administered was 4 (range: 2-29, total: 49). Four patients had >1 dose reduction due to the following reasons: fatigue (1), abnormal liver tests (2), hypertension and (Takotsubo) cardiomyopathy (1), and headaches (1). Common severe (Common Terminology Criteria for Adverse Events v3.0 grades 3-5) toxicities were as follows: hypertension (3/6), (Takotsubo) cardiomyopathy (2/6), diarrhea (1/6), fatigue (1/6), headache (1/6), and hematuria (1/6). One confirmed partial response was observed in PGL (17%, duration 2.4 years); median progression-free survival and overall survival were 6.5 and 14.8 months, respectively.

CONCLUSION

Pazopanib has activity in Pheo/PGL requiring more study; optimal alpha- and beta-blockade are imperative pre-therapy in patients with secretory tumors, as risk of hypertension and cardiomyopathy are potentially life threatening.