Tumours of the Adrenal Gland

Abstract

Each adrenal gland is related to the upper pole of corresponding kidney and therefore is also called a suprarenal gland. The adrenal gland consists of cortex and medulla, which embryologically, structurally and functionally are two separate entities [ 1 ]. The bulk of the gland is formed by the adrenal cortex, derived from mesoderm. There are three zones in the cortex: zona glomerulosa (the outermost layer producing mineralocorticoids -aldosterone), zona fasciculata (the middle layerglucocorticoids) and zona reticularis (the innermost layer producing androgens mainly dihydroepiandrosterone and androstendione). The medulla on the other hand is derived from ectoderm (neural crest) and contains chromaffi n cells, which store noradrenaline (20 %) and adrenaline (80 %) as secretory vesicles also known as chromaffi n granules. Some of the precursor chromaffi n cells migrate to the sides of the aorta mainly found at the origin of inferior mesenteric artery and bifurcation of aorta (organ of Zuckerkandl) [ 1 ]. Surgical AnatomyKnowledge of adrenal anatomy is important, as adrenalectomy is one of most commonly used modalities of treatment for adrenal conditions. The venous drainage of adrenal gland does not correspond anatomically to the arterial supply. There are three sets of adrenal arteries: (a) superior-a group of 6-8 arteries from inferior phrenic arteries (b) middle adrenal from the aorta (c) inferior adrenal (1-2 arteries from the