How to Answer? Way Question May be Asked? Concept Endocrine—Pheochromocytoma

Endocrine—Pheochromocytoma

Concept

Tumor of adrenal medulla producing excess catecholamines.

10% extraadrenal, pediatric, malignant, bilateral, familial (MEN2a or 2b).

Way Question May be Asked?

“24 y/o female sent to you for evaluation of her frequent headaches, palpitations, and BP of 190/110. What do you want to do?” May be given a history including flushing, sweating, episodic attacks, or young patient with new onset hypertension.

How to Answer?

History

Frequent “attacks”

Anxiety

Sweating/flushing Headaches Palpitations

Family history (MENIIa—hyperparathyroid, pheo, medullary thyroid CA)

Other neuroectodermal diseases (von Hippel-Lindau, tuberous sclerosis, neurofibromatosis)

Physical Exam

Blood pressure

Gentle abdominal exam (don’t want to compress organ of Zuckerkandl)

Palpate thyroid

Data

24 h urine for VMA, metanephrine, normetanephrine (make sure not on MAO inhibitor)

Ca

and calcitonin levels (r/o MENIIa)

Localization Studies

(1) CT scan abd/pelvis Look at adrenals

Look for extraadrenal tumors Look for metastases

(2) I-131 MIBG scan

(3) Portosplenic vein sampling (be prepared for results of this test or to describe how it’s done!)

(4) MRI

Surgical Treatment

Need to adequately prepare pt preoperatively

(1) Start alpha blocker two weeks prior to surgery, phe- noxybenzamine 20 mg bid and increase by 20 mg/day until BP and symptoms controlled

(2) Add Beta blocker 3 days prior to surgery, inderal 10 mg tid

(3) IVF hydration starting 2 days prior to surgery (typ- ically pts are volume contracted)

In OR, have rapid acting agents ready:

Neosynephrine Lidocaine Propranolol

Phentolamine (alpha-blocker) Have CVP (or SGC) and A-line

Do not use MSO

/Demerol (stimulates catechol release), or atropine (increases tachycardia)

Be prepared to describe right and left adrenalectomy and anatomy of adrenal vein on both sides!

Surgery

Midline incision

Full exploration of both adrenal glands, aortic bifurca- tion, bladder, kidney hilum

Control venous drainage first!

Excise tumor with minimal manipulation

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Debulk malignant tumors to help reduce symptoms Bilateral adrenalectomy for bilateral disease, MENII After tumor resected, give 1 mg glucagons to check

for occult tumor (tachycardia/inc. BP signs of resid- ual tumor).

Follow-Up

Urinary studies every 3 months, then yearly

Screen all family members yearly for pheo, medullary thyroid cancer, hyperparathyroidism

Common Curveballs

Won’t be able to localize pre-op

Won’t be able to localize intra-op (consider intra-op U/S)

Won’t have facilities to do rapid venous sampling Will be multiple tumors

Will be malignant tumor

Will have recurrent symptoms post-op

Will be part of MENII syndrome (which operation is performed first?)

Pt will have fluctuations of BP and HR intra-op

Strikeouts

Failing to ask about family history

Not knowing pre-op work-up or pre-op preparation of pt

Describing laparoscopic operation in pt with evidence of metastases, prior operations, or large tumor (> 8 cm)

Not ligating adrenal vein early in your description of operation

Not placing invasive hemodynamic devices intra-op Not screening relatives (for RET proto-oncogene) if

suspect MENII syndrome

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