adenomas

Adenomas are benign tumors that arise from glandular epithelium or other gland-forming tissues. They typically form by organized, gland-like structures and may show cellular changes such as dysplasia. Although they are noninvasive, some adenomas carry a risk of progressing to malignant tumors if left untreated, particularly in the colon.

Adenomas can occur in many organs, including the colon, pituitary, thyroid, adrenal glands, liver, and kidneys. Colon adenomas, or polyps, are the most studied type and are classified histologically as tubular, villous, or tubulovillous; the latter two carry a higher risk of cancer. Functional adenomas produce hormones, leading to clinical effects depending on the gland involved.

Pathology and risk: Most adenomas are asymptomatic. They may cause symptoms by mass effect or hormone excess. In the colon, risk of malignant transformation increases with size and the presence of villous features or high-grade dysplasia.

Diagnosis: Depends on location. Colon adenomas are commonly found during colonoscopy and confirmed by biopsy after polypectomy. Other adenomas are identified through imaging, laboratory tests for hormone levels, or incidental findings on imaging studies.

Treatment and prognosis: Management depends on site, size, and functional status. Endoscopic or surgical removal is standard for many adenomas; nonfunctioning, small adenomas may be observed with surveillance. Complete excision generally yields an excellent prognosis, though recurrence and surveillance needs vary by organ and histology.