How Do Doctors Know If an Adrenal Tumor Is Cancer?

Three things decide it. First, hormonal blood and urine tests show whether the tumour is producing hormones, which points to what it is. Second, imaging reveals its size, density and shape, small, smooth and stable usually means benign, while large, irregular and dense raises concern. Third, where doubt remains, the tumour is removed and examined under a microscope for the final answer. Most turn out benign.

According to Dr. Sandeep Nayak, Surgical Oncologist in India, “The reassuring part is that most adrenal tumours are benign, so this isn’t usually a cancer hunt, it’s a careful sorting process. I look at the hormones first, then the imaging, the size, the density on CT, how contrast washes out, the shape of the edges. Those tell me a great deal before any surgery. When the picture is genuinely unclear, removing it and examining it gives the definitive answer. Guesswork has no place here.”

The assessment follows a clear sequence, and each step narrows down the answer.

• Hormonal testing : Blood and urine tests show whether the tumour is functioning, pumping out hormones. This shapes both the diagnosis and how urgently it needs treating.
• Size : Size is one of the strongest clues. Small tumours are usually benign, while the risk of cancer climbs as a tumour gets larger.
• CT features : A CT scan looks at density and how contrast washes out. Benign adenomas are low density and wash out fast, cancers don’t.
• The margins : Smooth, well defined edges point to benign. Irregular borders, patchy internal texture and invasion into nearby tissue suggest something more serious.

This structured workup is the foundation of proper adrenal tumor treatment, where the evaluation before surgery matters as much as the surgery itself.

For most tumours a needle biopsy is the go to, but the adrenal gland is a different case.

• Biopsy is avoided : Sticking a needle into a suspected adrenal cancer risks spreading it, and it rarely helps. So doctors lean on imaging and hormones instead.
• The pheo trap : If the tumour is a pheochromocytoma, a biopsy can trigger a dangerous blood pressure crisis. Hormonal testing rules this out first.
• Surgery gives the answer : When a tumour looks suspicious, the safe route is removing it whole, then examining it. That confirms benign or malignant definitively.
• Whole is better : Taking the tumour out intact, rather than sampling it, both diagnoses and treats it in one step, without risking any spread.

Understanding what these growths are in the first place, covered in our guide on adrenal tumors, makes this evaluation much clearer.

Dr. Sandeep Nayak is a surgical oncologist with 24 years behind him and a fellowship in laparoscopic and robotic onco-surgery. He treats the full range of adrenal tumours, from benign functioning adenomas and pheochromocytomas to adrenocortical carcinoma, using robotic and laparoscopic adrenalectomy. The approach starts with thorough biochemical and imaging assessment, since with adrenal tumours the evaluation before surgery decides everything, including whether an operation is even needed.

Adrenal tumours reward careful, methodical assessment more than most. Rushing to surgery on a benign adenoma helps no one, while missing the features of a cancer costs precious time. Reading the hormones and imaging correctly, knowing when to watch and when to operate, and preparing properly for tumours like pheochromocytoma, that judgement is what separates safe adrenal care from risky guesswork. The evaluation is where the real expertise lies.

References

1. Differentiating benign from malignant adrenocortical tumors — National Library of Medicine
2. Diagnostic workup of adrenal incidentaloma — National Library of Medicine

Disclaimer: This blog is for informational and educational purposes only and is not a substitute for professional medical advice or diagnosis.