Pheochromocytoma

Is pheochromocytoma curable? All the information about its causes, symptoms, and treatments.

Symptoms and CausesDiagnosisTreatmentHospitalsMedical directory

Symptoms and Causes

Pheochromocytoma is a type of neuroendocrine tumor located in the adrenal glands, which sit atop the kidneys. It originates from chromaffin cells, which are responsible for synthesizing catecholamines (adrenaline, noradrenaline, and dopamine), hormones that play a role in the stress response. As a result, pheochromocytoma causes an increased and dysregulated secretion of catecholamines. Although this is a rare condition, it can have severe consequences.

Pheochromocytoma generally forms in the adrenal medulla, the inner part of the gland, but it can also develop in chromaffin cells located outside this area (in which case it is referred to as an extra-adrenal pheochromocytoma or paraganglioma).

Although pheochromocytomas are usually benign, in rare cases, they can be cancerous, with extra-adrenal pheochromocytomas being more prone to malignancy and metastasis.

Symptoms

The symptoms of pheochromocytoma result from the excessive production of catecholamines, leading to high blood pressure:

  • Tachycardia
  • Palpitations
  • Excessive sweating
  • Cold, clammy, and sticky skin
  • Pallor
  • Severe headache
  • Orthostatic hypotension: dizziness upon standing up
  • Increased respiratory rate
  • Chest and abdominal pain
  • Nausea and vomiting
  • Constipation
  • Vision disturbances
  • Tingling in the fingers
  • Anxiety, a sense of impending doom, intense and sudden fear

Pheochromocytoma symptoms typically present as paroxysmal hypertensive crises (sudden, intense, and usually brief episodes). Often, these crises have specific triggers, such as:

  • Pressure applied to the tumor
  • Postural changes
  • Abdominal massage
  • Use of beta-blockers or anesthetic drugs
  • Emotional trauma
  • Urination, if the pheochromocytoma is located in the bladder

In many cases, pheochromocytoma is asymptomatic and is only discovered incidentally during a medical test performed for another reason.

Causes

The development of pheochromocytomas is linked to mutations in certain predisposing genes: RET, VHL, NF1, SDHA, SDHB, SDHC, SDHD, SDHAF2, MDH2, IDH1, PHD1/PHD2, HIF2A/EPAS1/2, TMEM127, MAX, HRAS, MAML3, and CSDE1. These mutations can occur spontaneously or be inherited. In the case of inherited mutations, most are associated with one of the following genetic neoplastic syndromes:

  • Multiple endocrine neoplasia type 2A and 2B
  • Von Hippel-Lindau syndrome
  • Neurofibromatosis type 1
  • Hereditary paraganglioma syndrome
  • Carney-Stratakis syndrome
  • Carney syndrome

Risk Factors

Factors that increase the risk of developing pheochromocytomas include:

  • Age: It usually occurs in individuals aged 20 to 50.
  • Presence of one of the associated genetic syndromes.

Complications

Pheochromocytoma can have severe consequences, as hypertension can cause significant damage to vital organs, making it a major risk factor for strokes and cardiovascular diseases such as heart failure or myocardial infarction. Likewise, increased blood pressure can affect the renal arteries, interrupting blood flow and causing irreversible kidney damage. Vision loss can also occur if hypertension leads to bleeding in the eye, or hemorrhages and brain infarctions may develop if cerebral blood flow is interrupted.

In rare cases where pheochromocytoma is cancerous, it can spread through the lymphatic system and the rest of the body, affecting organs such as the bones, liver, or lungs, significantly reducing life expectancy.

Prevention

No preventive measures have been identified for pheochromocytoma.

Which Specialist Treats Pheochromocytoma?

Pheochromocytoma is diagnosed and treated by specialists in endocrinology and oncology.

Diagnosis

Pheochromocytoma can be difficult to detect because, in many cases, persistent hypertension is the only symptom. It is only suspected when frequent hypertensive crises occur or when persistent hypertension does not respond to medication. To confirm the diagnosis, the following tests are performed:

  • Blood and urine tests: These measure catecholamine levels and their metabolites (metanephrines). Elevated levels indicate pheochromocytoma.
  • Imaging tests: If laboratory tests are positive, the tumor’s location is identified through magnetic resonance imaging (MRI) or computed tomography (CT) scans.
  • Genetic studies: DNA from a blood, saliva, or mucosal sample is analyzed to identify the genetic mutation causing pheochromocytoma and to confirm the presence of an associated genetic syndrome.

Treatment

Once identified, pheochromocytomas must be treated promptly. The primary approach is surgical tumor removal:

  • Preoperative pharmacological treatment: To control blood pressure before surgery, alpha-blockers are administered for one to two weeks to stop catecholamine secretion. Once secretion is halted, beta-blockers are introduced to dilate blood vessels, increase blood flow, and lower blood pressure. This treatment must be administered continuously when the pheochromocytoma is cancerous and cannot be removed.
  • Adrenalectomy: The affected adrenal gland and tumor are removed. If tumors are present in both glands or if one has already been removed, only the tumor and minimal surrounding healthy tissue are excised. Surgery can be performed using laparoscopy for small tumors or open abdominal surgery for larger pheochromocytomas. Additionally, if the pheochromocytoma is malignant and has spread, tumor resection surgery remains the first-line treatment.
  • Chemotherapy or targeted therapy: If the entire malignant tumor cannot be removed, different medications, such as temozolomide or sunitinib, are administered to attack the tumor tissue and slow its growth.