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Adrenal Cancer
Overview Adrenal cancer is a rare disease that originates in the adrenal glands. The adrenal glands are located on top of the kidneys and consist of two parts that function separately: the outer layer (cortex) and the inner area (medulla). The cortex produces three major hormones: cortisol (a glucocorticoid), aldosterone (a mineralocorticoid), and dehydroepiandrosterone (DHEA; an androgen). The medulla produces epinephrine (adrenaline), norepinephrine, and dopamine. Adrenal tumors can increase hormone production (called functioning tumors). Adrenal tumors that do not produce hormones are called nonfunctioning. Symptoms of adrenal cancer and treatment for the condition depend on whether the tumor is functioning or nonfunctioning, and on which hormone is being overproduced. Types The most common type of adrenal cancer develops in the adrenal cortex and is called adrenocortical carcinoma. Functioning adrenocortical carcinomas may produce symptoms related to increased hormone production. Nonfunctioning tumors may cause pain from pressure on abdominal organs and a mass in the abdomen that is able to be felt with the fingers (palpable). Cancers that develop in the adrenal medulla include neuroblastoma (originates in undeveloped nerve cells) and pheochromocytoma (originates in cells that produce epinephrine and norephinephrine). Neuroblastoma usually occurs in infants and children and pheochromocytoma more commonly occurs in people who are in their 30s and 40s. Other types of cancer (e.g., breast, lung) may spread (metastasize) to the adrenal glands. Incidence and Prevalence The cause of adrenal cancer is unknown and most cases do not have identifiable risk factors. In some cases, heredity plays a role in the development of the disease. Li-Fraumeni syndrome and type 1 multiple endocrine neoplasia (MEN1) are genetic mutations in tumor suppressor genes that increase the risk for several types of cancer, including adrenal cancer. Genetic testing may be recommended in families with a high incidence of suspected tumor suppressor gene mutation. Other familial syndromes associated with adrenal cancer include:
Signs and Symptoms Adrenal cancer does not always produce symptoms. Both nonfunctioning adrenocortical carcinomas and large functioning tumors may cause the following:
Additional symptoms of functioning adrenocortical carcinoma depend on which hormones are overproduced. Overproduction of androgens (e.g., dehydroepiandrosterone, estrogen) usually does not produce symptoms in men because the testicles produce testosterone, which is a more potent androgen. Rarely, abnormal breast enlargement (gynecomastia) occurs in men. Excess androgens may cause early puberty in children and masculinization (i.e., abnormal facial and body hair, deepening voice) in women and children. A functioning adrenocortical tumor that produces excess cortisol may result in Cushing’s syndrome. Approximately 30–40% of patients with Cushing's syndrome and an adrenal mass are diagnosed with adrenal cancer. Symptoms of Cushing's syndrome include the following:
Conn’s syndrome is caused by increased aldosterone production and may result from a functioning tumor in the adrenal cortex. Symptoms of Conn's syndrome include the following:
The hallmark of pheochromocytoma is sudden or sustained high blood pressure that is often resistant to treatment. Other symptoms include severe headaches, sweating, heart palpitations (rapid pulse), and nausea. Symptoms of neuroblastoma include abdominal pain and bone pain resulting from metastatic disease. Diagnosis of adrenal cancer involves taking a medical history and performing a physical examination, blood and urine tests, imaging tests, and a biopsy. Medical history includes family history of adrenal cancer, menstrual (in women) and sexual history, and the patient’s history of symptoms. Physical examination includes palpating (feeling with the fingers) the abdomen for evidence of an adrenal mass. Blood and Urine Tests Imaging Tests CT scan uses x-rays to produce detailed images of the adrenal glands, other abdominal organs, and lymph nodes. In some cases, a contrast agent (dye) is used to detect metastasis. MRI uses magnetic fields to produce a cross-sectional image that detects abnormal enlargement of the adrenal gland. This test may be used to help determine if adrenal tumors are benign or cancerous (malignant). Biopsy Treatment for adrenal cancer depends on the stage of the disease at diagnosis. Options include surgery, chemotherapy, and radiation. Treatment for patients with functioning tumors usually involves using medications to manage symptoms. Pheochromocytomas require treatment before surgery (neoadjuvant treatment) for high blood pressure, which often includes alpha-blockers (e.g., phenoxybenzamine, prazosin) followed by beta-blockers (e.g., propranolol), and metyrosine. Surgery Chemotherapy Mitotane (Lysodren®) suppresses adrenal gland function and is the drug of choice to treat inoperable adrenal cancer. Approximately 20% of adrenal cancer patients respond to treatment with mitotane. Side effects include gastrointestinal disturbances (e.g., loss of appetite, nausea, vomiting, diarrhea) and neurological disturbances (e.g., depression, lethargy, sleepiness). When mitotane therapy fails, cisplatin (Platinol®) may be tried, alone or combined with other agents. Drug combinations used include the following:
Side effects of chemotherapy are often severe and include gastrointestinal disturbances, low blood count (anemia), skin disorders, and neurological disorders. Radiation Therapy Medical Management of Functioning Tumors Increased cortisol production (Cushing's syndrome) is often treated with aminoglutethimide or ketoconazole (Nizoral®) to inhibit cortisol build-up (synthesis). They may be used alone, or in combination with chemotherapy. Side effects include nausea, vomiting, and abdominal pain. Excess aldosterone production (Conn’s syndrome) is usually treated using spironolactone (Aldactone®). Spironolactone is an aldosterone antagonist (i.e., counteracts the action of aldosterone). Side effects include ulcers, abnormal breast enlargement in men (gynecomastia), fever, and headache. Aromatase inhibitors such as anastrozole (Arimidex®) and anti-androgens such as bicalutamide (Casodex®) may be used to treat excessive androgen production. Prognosis The prognosis for adrenal cancer depends on the stage of the disease. Metastatic tumors have a poor prognosis. The 5-year survival rate when surgical removal of the cancer is achieved is approximately 40%. About 80% of cases recur within 10 years after treatment. Prevention Adrenal cancer cannot be prevented. Content © Copyright Urology
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