Arterial embolization for ruptured adrenal pheochromocytoma

Adrenal pheochromocytomas are uncommon catecholamine-secreting tumours. In general outpatient clinics, the prevalence of pheochromocytoma in patients with hypertension is 0.1%–0.6% 1–3. The classic triad of pheochromocytoma presentation is episodic headache, sweating, and palpitations. Pheochromocytoma is typically found with a diverse set of symptoms, which may include anxiety, chest and abdominal pain, visual blurring, papilloedema, nausea and vomiting, orthostatic hypotension, and transient electrocardiographic changes 4. Spontaneous rupture of adrenal pheochromocytoma is extremely rare, with only about 50 cases reported in the literature to the date of writing 5. The mechanism of pheochromocytoma rupture is unknown, but high intracapsular pressure may tear the capsule and cause necrosis of the tumour 6. Here, we describe a patient with ruptured right adrenal pheochromocytoma presenting with hypertension and abdominal pain, and we review the literature for similar cases. To best of our knowledge, this case is the first to be reported showing ruptured adrenal tumour with large retroperitoneal and subcapsular hematoma of the right kidney and with safe coil embolization for the adrenal and renal arteries.


INTRODUCTION
Ad renal pheoch romocy tomas are uncom mon catecholamine-secreting tumours.In general outpatient clinics, the prevalence of pheochromocytoma in patients with hypertension is 0.1%-0.6% 1-3.The classic triad of pheochromocytoma presentation is episodic headache, sweating, and palpitations.Pheochromocytoma is typically found with a diverse set of symptoms, which may include anxiety, chest and abdominal pain, visual blurring, papilloedema, nausea and vomiting, orthostatic hypotension, and transient electrocardiographic changes 4 .Spontaneous rupture of adrenal pheochromocytoma is extremely rare, with only about 50 cases reported in the literature to the date of writing 5 .The mechanism of pheochromocytoma rupture is unknown, but high intracapsular pressure may tear the capsule and cause necrosis of the tumour 6 .
Here, we describe a patient with ruptured right adrenal pheochromocytoma presenting with hypertension and abdominal pain, and we review the literature for similar cases.To best of our knowledge, this case is the first to be reported showing ruptured adrenal tumour with large retroperitoneal and subcapsular hematoma of the right kidney and with safe coil embolization for the adrenal and renal arteries.

CASE DESCRIPTION
A 42-year-old Palestinian man referred to the European Gaza Hospital emergency room presented with sudden onset of right-side upper abdominal pain radiating to the right flank and accompanied by sweating and palpitations for the preceding 24 hours.
In the 2 weeks before this presentation, the patient had recurrently experienced similar symptoms.He had been admitted to another hospital, where he

Background
Spontaneous rupture of adrenal pheochromocytoma is an extremely rare condition that can be lethal.Optimal treatment in these cases is still unclear.

Methods
We conducted a comprehensive review of medline articles on ruptured pheochromocytomas to locate all research done on this topic.Based on the literature review and one additional case at European Gaza Hospital, we analyzed clinical presentations, hemorrhage site, tumour side, mortality rate, and treatment options.

Results
In addition to our case, we identified 53 cases of ruptured pheochromocytoma.A review of all 53 cases revealed that 17 (32%) of the patients died, and that no mortality occurred among the 12 patients who received an alpha-blocker (to control high blood pressure) and fluid infusion therapy before surgery.Only 3 patients, including our case, underwent elective surgery after transcatheter arterial embolization (tae).

Conclusions
Surgical treatment should be considered for ruptured pheochromocytoma.Surgical approaches involve either emergency or elective surgery.It has been reported that emergency surgery is commonly associated with a high mortality rate; no deaths were reported in patients who underwent elective surgery.We therefore consider that, if a patient has hemodynamic instability, tae can be an effective and a safe procedure for achieving hemostasis and maintaining the patient in good condition until surgery can be performed.underwent an urgent abdominal computed tomography (ct) scan with contrast, which demonstrated a large tissue mass in the right adrenal gland region with intracapsular bleeding and a large hematoma in the right retroperitoneal space (Figure 1) and subcapsular hematoma in the right kidney (Figure 2).At that time, he was urgently referred to Egypt, but unfortunately, he was denied entry.
We performed abdominal aortography using a right femoral approach.Selective angiograms of the celiac, superior mesenteric, and right renal artery were obtained, with subsequent selective cannulation of the right renal and adrenal arteries using a Judkins right 6 French catheter (Figure 3).
Because of the subcapsular hematoma in the right kidney, urinary protein 2+, urinary occult blood 3+, an arterial supply of the right suprarenal gland was performed from the right renal and medial and lateral suprarenal arteries.With back and abdominal pain and hypertension continuing despite medical treatment, the patient was at high risk for surgery.We therefore suggested transcatheter arterial embolization (tae) for the renal and suprarenal arteries.
A tae using coils was then performed on the medial and lateral branches of the right adrenal and renal artery using 3 French microcatheters.Subsequent dye injection demonstrated complete obliteration of the tumour's vascular supply.Immediately after embolization, the patient's vital signs stabilized, and his blood pressure normalized to 130/90 mmHg.After 48 hours, his abdominal and flank pain had completely resolved.
A follow-up abdominal ct examination 2 weeks post tae showed significant resolution of the retroperitoneal hematoma.In addition, the tumour was also better delineated than it had been in the imaging done before the tae procedure (Figure 4).
One month after the coil tae, the patient underwent elective right adrenalectomy and nephrectomy.Pathology findings confirmed the diagnosis of pheochromocytoma.The adrenal gland tumour was composed of cells possessing round nuclei and abundant eosinophilic cytoplasm, arranged in a Zellballen Current OnCOlOgy-VOlume 17, number 6 pattern.Hemosiderin pigmentation and coagulation necrosis were frequently seen.

LITERATURE REVIEW
Since the first description of ruptured pheochromocytoma by Cahill in 1944 7 , a total of 53 cases, including the present one, have been reported in the literature.No difference in frequency between men and women has been reported, and median age of the patients was 50.1 years.Table i summarizes the 53 cases 8-56 .

Presentation
Analysis of the literature shows that 79% of the patients presented with acute abdominal pain, 19% with chest pain, 24.5% with lumbar pain, and 57% with shock.One case presented with acute myocardial infarction 52 .

Treatment
Surgical excision was performed in 44 cases.In 12 patients, the surgery was elective after the patient had been stabilized with an alpha-blocker (to control high blood pressure) and fluid infusion therapy.In 3 patients, the surgery was elective after tae.In 29 cases, the surgery was emergent, and in 9 patients, surgery was not performed.

Outcome
The mortality rate was high: one third of the patients [17 (32%)] died.No mortality occurred among the 15 patients who received alpha-blocker and fluid infusion therapy, or who were treated by tae before elective surgery.All 17 who died were among the 38 patients (44.7%) who did not undergo elective surgery after appropriate medical preparation.

Transcatheter Arterial Embolization
The literature shows that only 3 patients (including our case) underwent elective surgery after tae (Table ii

):
Case 1 A 67-year-old man was admitted to the emergency department with a 1-day history of severe right abdominal and back pain associated with diaphoresis, nausea, and vomiting.Imaging by ct demonstrated a right adrenal mass with retroperitoneal hemorrhage.A tae using polyvinyl alcohol particles was done to the right adrenal artery, and 2 months later, the patient underwent elective right adrenalectomy 53 .

Case 2
A 32-year-old man presented with sudden right abdominal pain, and urgent ct imaging demonstrated a Multiple symptoms reported when applicable.tae = transcatheter arterial embolization.
a bilateral adrenal mass with hemorrhage in the right adrenal mass.Coil embolization was done to the right adrenal artery, and 21 days later, resection of the right adrenal gland was performed 54 .

Case 3 (present case)
A 42-year-old man with a large retroperitoneal hematoma, hemorrhage in the right adrenal mass, and hypertension underwent tae by coils to the right renal and the adrenal arteries to achieve hemostasis.Surgery was performed 1 month later.

DISCUSSION
Pheochromocytomas are uncommon catecholaminesecreting tumours.Rupture of an adrenal pheochromocytoma is extremely rare and can be lethal because of dramatic changes in the circulation.The exact mechanism of pheochromocytoma rupture is unknown, but high blood pressure attributable to a massive release of catecholamine into the circulation is probably associated with vasoconstriction in the tumour and subsequent necrosis, hemorrhage, and elevated intracapsular pressure.Additionally, rapid tumour growth may contribute to high intracapsular pressure.High pressure in the intracapsular region may also result in a tear in the capsule, causing retroperitoneal hemorrhage.
Abdominal pain may be related to stimulation of alpha-adrenergic receptors, constriction of intestinal vascular smooth muscle, and contraction of the ileocolic sphincter.High levels of circulating catecholamines will therefore result in a decrease of intestinal motility and tone 55 .
The application of tae allows for hemostasis, with consolidation of the hematoma; surgery can subsequently be performed easily and without complications 56 .

CONCLUSIONS
When adrenal pheochromocytoma has been diagnosed, surgical treatment should be considered.Surgical approaches for ruptured pheochromocytoma involve either emergent or elective surgery.Immediate surgery is associated with a high mortality rate (44.7%); no mortality has been reported in patients who undergo elective surgery after good blood pressure and total body water control has been achieved using alpha-adrenergic blocker and f luid infusion therapy, or after stabilization by ta e.
Phentolamine mesylate is a useful alpha-adrenergic blocker to control blood pressure in patients with pheochromocytoma.If initial conservative therapy can control retroperitoneal hemorrhage and blood pressure, a watch-and-wait approach is safe and less invasive for the patient, avoiding the risk of re-bleeding.If, despite medical treatment, the patient is unstable because of uncontrolled blood pressure or recurrent abdominal pain or persistent bleeding, we therefore conclude that tae should be the first treatment option in the attempt to achieve hemostasis before surgery-an approach that should reduce mortality and maintain the patient in good condition.

figure 1 3
figure 1 Right adrenal mass with retroperitoneal hematoma and intratumoral bleeding.

figure 4
figure4 Significant resolution of the retroperitoneal hematoma.

table i
Clinical characteristics of 53 patients with spontaneous ruptured pheochromocytoma 1. Anderson JH Jr, Blakeman N, Streeten DH.The effect of age on prevalence of secondary forms of hypertension in 4429 consecutively referred patients.J Hypertens 1994;12:609-15.2. Omura M, Saito J, Yamaguchi K, Kakuta Y, Nishikawa T. Prospective study on the prevalence of secondary hypertension among hypertensive patients visiting a general outpatient clinic in Japan.Hypertens Res 2004;27:193-202.

table ii
Summary of the 3 cases of ruptured pheochromocytoma treated with transcatheter arterial embolization (tae)