The adrenal gland is a pair of hormone producing organs above the kidneys. It is composed of an inner medulla and an outer layer called the cortex. Like other tissues in the body it can be subject to the development of tumors. A tumor is an abnormal overgrowth of tissue that does not serve a physiological function. They may be benign or malignant. The main difference between benign and malignant tumors is that benign tumors grow in place and malignant tumors migrate through the body, a process termed metastasis. Adrenal tumors may be benign or malignant and are found in the cortex or medulla.
Benign Cortical Tumors
The most common type of benign adrenal tumor is located in the outer cortex and is called an adrenocortical adenoma. These tumors are often found incidentally on imaging scans such as CT or MRI or during autopsy. According to Pathology Outlines.com, they are thought to be present in about 5% of the population, and two-thirds of those found are in women. They are generally asymptomatic, but they may produce hormones such as estrogen, testosterone, aldosterone or cortisol, which can have effects on the body. Symptomatic benign cortical tumors may be surgically removed. According to "Rubin's Pathology" by Rubin and Strayer, other benign tumors include those associated with other syndromes, myxoid, or mucus-like, tumors, cysts, and tumors of various other tissues such as fat, blood vessels, connective tissue and smooth muscle.
Cancerous Cortical Tumors
The most common cancerous tumor in the cortex is the adrenocortical carcinoma. Half of these produce hormones that cause symptoms, such as virilization of women, which imparts masculine features such as hair growth and deepening of the voice if the hormone is testosterone. They tend to spread to the nearby blood vessels, liver, lungs and nearby lymph nodes. Similar to benign tumors, other types of cancerous tumors in the cortex include those of other tissue and cell types.
Medullary Tumors
According to "BRS Pathology" by Schneider and Szanto, medullary tumors are generally of two types: pheochromocytoma or neuroblastoma. Pheochromocytomas are tumors of the cells in the medulla that produce epinephrine and norepinephrine, the fight or flight hormones known commonly as adrenalin and noradrenalin. These tumors follow a "rule of tens" in that very roughly 10% are cancerous, 10% are found in both adrenals, 10% are found outside the adrenal glands and 10% appear to be part of inherited conditions. Symptoms are generally from excessive fight or flight hormones, including high blood pressure, sudden severe headaches, fear, anxiety and weight loss.rnrnNeuroblastomas also produce fight or flight hormones, but unlike pheochromocytomas, these are always aggressive cancers. They are derived from nerve cells in the adrenal medulla and tend to occur in children. The cancer generally causes a large abdominal mass which may even fill the abdomen or chest; it may also cause weight loss and fever.
