Ectopic Hormones-Secreting Pheochromocytoma: A Francophone Observational Study

Background Ectopic hormone-secreting pheochromocytomas
<br />are rare; only case reports exist in the literature. This
<br />condition has been linked with increased malignancy,
<br />familial syndromes, and ACTH secretion. We wanted to
<br />test these hypotheses and shed light on the nature of ectopic
<br />hormone-secreting pheochromocytomas.
<br />Methods This is a multicenter (francophone) observational
<br />study. Inclusion was based upon abnormal preoperative
<br />hormone tests in patients with pheochromocytoma
<br />that normalized after removal of the tumor. Where
<br />possible, immunohistochemistry was performed to confirm
<br />that ectopic secretion came from the tumor.
<br />Results Sixteen cases were found: nine female and seven
<br />male patients. Median age was 50.5 (range 31–89) years.
<br />Most presented with hypertension, diabetes, or cushingoid
<br />features. Ten patients had specific symptoms from the
<br />ectopic hormone secretion. Two had a familial syndrome.
<br />Of eight patients with excess cortisol secretion, three died
<br />as a result of the tumor resection: two had pheochromocytomas[
<br />15 cm and their associated cortisol hypersecretion
<br />complicated their postoperative course. The other died
<br />from a torn subhepatic vein. The 13 survivors did not
<br />develop any evidence of malignancy during follow-up
<br />(median 50 months). Symptoms from the ectopic secretion
<br />resolved after removal of the tumor. Immunohistochemistry
<br />was performed and was positive in eight tumors: five
<br />ACTH, three calcitonins, and one VIP.
<br />Conclusions Most pheochromocytomas with ectopic
<br />secretion are neither malignant nor familial. Most ectopic
<br />hormone-secreting pheochromocytoma cause hypercortisolemia.
<br />Patients with a pheochromocytoma should be
<br />worked up for ectopic hormones, because removal of the
<br />pheochromocytoma resolves those symptoms. Associated
<br />cortisol secretion needs careful attention.