Successful induction therapy with sequential CVD followed by high-dose lanreotide in for metastatic SDHB paraganglioma: Case report

Objective Pheochromocytomas (PHEOs) and paragangliomas (PGLs) arise from adrenal extra-adrenal paraganglia. They often secrete catecholamine and approximately 1/3 are hereditary. Almost 50% of metastatic PGLs are caused by mutations in the succinate dehydrogenase gene, particularly in subunits B and D (SDHB/D). These tumors remain a diagnostic and therapeutic challenge due to a limited number of effective treatment options. To our best knowledge, we present the first report that uses induction therapy to elicit a significant response in both primary and metastatic lesions, followed by complete surgical resection of a primary SDHB-related PGL. Case description A 45-year-old female presented with an 8.5 cm unresectable primary SDHB-related PGL with multiple bone metastases. She had an initial blood pressure of 210/130 mmHg and a heart rate of 150 bpm. Initially, she was treated with cisplatin, vinblastine, and dacarbazine (CVD) chemotherapy and lanreotide (120 mg/sc/28d), which resulted in tumor shrinkage. The patient later progressed, and monotherapy with a shortened interval of lanreotide (120 mg/sc/14d) was initiated. Following 2.5 months at this interval, the patient nearly achieved complete control of her clinical symptoms, and experienced a 30% reduction in ¹⁸F-flurodeoxyglucose uptake in her primary and metastatic lesions. Following the surgical resection of her primary PGL, all prior antihypertensive medications were stopped. Conclusions CVD, together with a 14-day regimen of high dose lanreotide, may be an effective treatment option for SDHB-related metastatic PGLs. Therefore, further evaluation of somatostatin analogues, preferably lanreotide, in the treatment of metastatic SDHB-related PGLs is warranted. We believe that ours is the first report detailing the successful use of lanreotide treatment prior to a surgical rescue after systemic treatment.