Endocrine Abstracts

Introduction: Pheochromocytomas are rare neuroendocrine tumors arising from chromaffin cells of the adrenal medulla. Approximately 10% of all pheochromocytomas are malignant. There is no effective therapy for malignant pheochromocytoma (MAL-PHEO) and the overall prognosis is poor.

Case report: We report 22-year survival with MAL-PHEO in a patient treated with several surgeries, ¹³¹I-metaiodobenzylguanidine and, subsequently, with long-acting formulation of octreotide (octreotide-LAR) for 10 years.

In 1990, a 43-year-old woman was diagnosed with pheochromocytoma. She underwent left radical nephrectomy and adrenalectomy in 1990. In 1993 and 1995, the patient underwent subsequent operations because of the tumor recurrence. In 2002, metastases in the thoracic vertebrae with a compression on the dural sac were found and the patient underwent surgical decompression in 2002 and 2004.

At referral to our Department in 2002, patient’s serum chromogranin A was 342 U/l (normal range: 2–18 U/l). Somatostatin receptors scintigraphy with ⁹⁹mTc-EDDA/HYNIC-TOC revealed multiple vertebral and lymph nodes metastases with high expression of somatostatin receptors. In February 2003, the therapy with octreotide-LAR (20 mg i.m. every 28 days) was started. In 2004/2005 the patient was treated with ¹³¹I-metaiodobenzylguanidine with a partial radiological and complete biochemical tumor response. The therapy with octreotide-LAR has been carried on from 2003 until the present time. Until 2010 radiological and biochemical stabilization of the disease had been observed. In 2010 the presence of lung metastases was revealed. Patient’s serum chromogranin A increased (286 U/l in September 2012), however 24-hour urinary excretion of metanephrines is within normal range. Currently, the patient is under consideration for the treatment with radiolabeled octreotide derivates.

Conclusions: This is the first report of long-term treatment with octreotide in a patient with MAL-PHEO. Our findings suggest that, as it has been recently shown in patients with metastatic midgut neuroendocrine tumors, the treatment with octreotide-LAR may prolong survival and time to tumor progression in patients with MAL-PHEO.