STANDARD TREATMENT OPTIONS: [1,2,3,4,5,6]

Pheochromocytoma with regional lymphatic metastasis or local extension should be treated by aggressive surgical resection with an attempt to remove all gross evidence of disease. If this is accomplished, and confirmed by biochemical determinations, long-term survival may be achieved. These patients, however, will require careful monitoring indefinitely for recurrent disease. If regional disease remains, the hypertension and symptoms caused by catecholamine excess should be treated by adrenergic blockade and catecholamine synthesis inhibition as necessary.

Radiation therapy or combination chemotherapy may be palliative for symptoms or morbidity resulting from local invasion by tumor. Treatment with targeted radiation therapy using I¹³¹ meta-iodobenzylguanidine (I¹³¹ MIBG) has met with limited success. In approximately 35% of the patients screened, the tumor has sufficient uptake of the radioisotope to allow for a therapeutic dose.[7,8] In a group of 28 patients shown to have sufficient uptake of I¹³¹ MIBG, objective partial responses were observed in 29% of the patients, and biochemical improvement was noted in 43% of the patients.[9]

Several single agents and drug combinations have been evaluated in a limited number of patients with variable results.[7] The most active chemotherapy regimen appears to be the combination of cyclophosphamide, vincristine, and dacarbazine (CVD).[10] CVD has been shown to produce partial remissions of moderate duration in symptomatic patients. Analysis of 23 patients treated with CVD showed 61% of the patients had objective evidence of tumor regression, and 74% of the patients had evidence of biochemical response. In addition, improved control of hypertension, reduced need for antihypertensive medications, and improvement in overall performance status was observed. Since hypertensive episodes have been reported following chemotherapy, patients need to be prepared with adrenergic blockers prior to treatment. No evidence exists that chemotherapy contributes to improved patient survival. Chemotherapy should be used only for palliation in symptomatic patients.[7,11]

References:

1. Manger WM, Gifford RW: Pheochromocytoma. New York: Springer-Verlag, 1977.
2. Norton JA: Adrenal tumors. In: DeVita VT Jr, Hellman S, Rosenberg SA, eds.: Cancer: Principles and Practice of Oncology. 7th ed. Philadelphia, Pa: Lippincott Williams & Wilkins, 2005, pp 1528-39.
3. Young JB, Landsberg L: Catecholamines and the adrenal medulla: pheochromocytoma. In: Wilson JD, Foster DW, Kronenberg HM, et al., eds.: Williams Textbook of Endocrinology. 9th ed. Philadelphia, Pa: W.B. Saunders Company, 1998, pp 705-716.
4. Remine WH, Chong GC, Van Heerden JA, et al.: Current management of pheochromocytoma. Ann Surg 179 (5): 740-8, 1974.
5. McEwan AJ, Shapiro B, Sisson JC, et al.: Radio-iodobenzylguanidine for the scintigraphic location and therapy of adrenergic tumors. Semin Nucl Med 15 (2): 132-53, 1985.
6. Drasin H: Treatment of malignant pheochromocytoma. West J Med 128 (2): 106-11, 1978.
7. Kvols LK, Perry RR, Vinik AI, et al.: Neoplasms of the neuroendocrine system and neoplasms of the gastroenteropancreatic endocrine system. In: Holland JC, Frei E, eds.: Cancer Medicine e.5. 5th ed. Hamilton, Ontario: B.C. Decker Inc, 2000, pp 1121-1172.
8. Shapiro B, Fig LM: Management of pheochromocytoma. Endocrinol Metab Clin North Am 18 (2): 443-81, 1989.
9. Shapiro B, Sisson JC, Wieland DM, et al.: Radiopharmaceutical therapy of malignant pheochromocytoma with [131I]metaiodobenzylguanidine: results from ten years of experience. J Nucl Biol Med 35 (4): 269-76, 1991 Oct-Dec.
10. Averbuch SD, Steakley CS, Young RC, et al.: Malignant pheochromocytoma: effective treatment with a combination of cyclophosphamide, vincristine, and dacarbazine. Ann Intern Med 109 (4): 267-73, 1988.
11. Brennan MF, Keiser HR: Persistent and recurrent pheochromocytoma: the role of surgery. World J Surg 6 (4): 397-402, 1982.