paraganglima. and pheochromocytoma

1. Pheochromocytomas and
paragangliomas
Prof. Ahmed M Badheeb, MD,

2. Pheochromocytomas and
paragangliomas
• are catecholamine-secreting neuroendocrine
tumors that arise from:
• chromaffin cells of the adrenal medulla (in
the case of pheochromocytomas)
• and
• the extra-adrenal autonomic paraganglia (in
the case of paragangliomas).

3. Paragangliomas
• can arise in the skull base and neck (where the
majority are nonsecretory), or below the neck
in the thorax or abdomen (where the majority
are secretory).

4. Metastasis Potential
• Most pheochromocytomas/paragangliomas ar
e benign.
• Approximately 10 % of pheochromocytomas
are malignant (as defined by the presence of
metastases)
• 20 to 25 % of extra-adrenal abdominal and
mediastinal secretory paragangliomas.

5. malignant skull base and neck
paragangliomas
• In the skull base and neck, malignancy is least common for
jugulotympanic tumors (2 to 4 %), slightly higher for carotid
body tumors (4 to 6 %), and highest for vagal tumors (10 to
19 %).
• Among patients with malignant skull base and neck
paragangliomas, metastases are most frequently limited to
the regional lymph nodes. In contrast, patients with
paragangliomas below the skull base and neck most
frequently have distant metastases, most commonly to the
bone, liver, and lung.
•

6. Surgery with mets
• While the presence of distant metastatic
disease has an adverse effect on prognosis,
metastases do not necessarily represent a
contraindication to resection of the primary
tumor, particularly if the metastases are
surgically resectable.

7. The prognosis with mets
• variable.
• Long-term survival is possible even in the
presence of distant metastatic disease, but
five-year survival rates are ≤50 percent.

8. Symptoms of catecholamine excess
• should be controlled using combined alpha-
and beta-adrenergic blockade.

9. Surgery with mets
• We suggest resection of both the primary and metastatic
lesions, if possible (Grade 2C).
• Even if complete eradication is not achievable, a
cytoreductive incomplete resection can improve symptoms,
reduce hormone secretion, prevent complications related
to tumor in a critical anatomic location, and improve the
response to subsequent therapies.
• However, there is no evidence that surgical debulking
prolongs survival in patients with metastatic disease.

10. Preoperative control
• Preoperative control of the effects of excessive
adrenergic stimulation is necessary using
combined alpha- and beta-blockade.
• In addition, preoperative and intraoperative
treatment with volume expansion is required
to prevent intraoperative hypotension.

11. If not candidates for resection,
• For patients who are local control of bulky
symptomatic disease, particularly painful
bone metastases, can be achieved with
external beam radiation therapy (EBRT).

12. Percutaneous ablation of mets
• radiofrequency ablation
• cryoablation
• ethanol injection

13. If multiple liver-isolated mets
• transarterial chemoembolization

14. preprocedure medical preparation
• •Any form of local therapy can induce massive
catecholamine secretion and a hypertensive
crisis; preprocedure medical preparation is
needed.

15. MIBG-positive tumors
• 60 % of pheochromocytomas/paragangliomas take up meta-
iodobenzylguanidine (MIBG) as determined by 123I-MIBG scintigraphy.
• For patients with MIBG-positive tumors who have unresectable,
symptomatic progressive disease that is not amenable to locoregional
methods of control, or those with a high tumor burden who have a
low number of bone metastases, we suggest 131I-MIBG rather than
systemic chemotherapy as a first-line approach (Grade 2C).
• There is no consensus as to the relative efficacy of high-dose versus
fractionated medium doses of 131I-MIBG, and specific
recommendations as to the best dose and treatment schedule cannot
be made.

16. Role of chemotherapy
• For patients with rapidly progressive tumors
or disease that is predominantly localized to
the skeleton, chemotherapy is preferred even
if 123I-MIBG scintigraphy is positive. Although
the optimal regimen is not established, we
suggest combination chemotherapy
with cyclophosphamide, vincristine,
and dacarbazine (Grade 2C).

17. sunitinib
• ●Preliminary reports suggest
that sunitinib may be an active agent, and
further ongoing studies should provide more
information on its utility; hypertension is a
prominent side effect. Sunitinib can be safely
used, even for patients with symptoms of
catecholamine excess, as long as strict follow-
up and aggressive antihypertensive dosage
adjustments are performed