**Question:** Incidental finding in CT scan, a 3cm adrenal mass, which of the following is not done

A. Adrenal venous sampling (AVS)
B. Adrenal venous catheterization
C. Adrenal biopsy
D. Adrenalectomy

**Core Concept:**
Adrenal masses can be detected incidentally during imaging studies, prompting a need to evaluate and manage them appropriately. Depending on the size and characteristics of the mass, a variety of diagnostic and therapeutic modalities are employed. In this case, we consider a 3cm adrenal mass.

**Why the Correct Answer is Right:**
In this scenario, adrenal venous sampling (AVS) is not the correct action to take with a 3cm adrenal mass detected incidentally in a CT scan. AVS is an invasive procedure involving the insertion of a catheter into the adrenal veins to measure hormone levels, typically used to differentiate between primary aldosteronism and Cushing's syndrome. Given the simplicity of CT scan, we prefer non-invasive methods for evaluation of adrenal masses.

**Why Each Wrong Option is Incorrect:**

B. Adrenal venous catheterization (like AVS) is an invasive procedure, and therefore not suitable for evaluating a 3cm adrenal mass incidentally found on CT scan.
C. Adrenal biopsy is also an invasive procedure with potential complications, and is generally not the first-line method for evaluating an adrenal mass on a CT scan. Instead, imaging studies and clinical evaluation are typically employed first.
D. Adrenalectomy (surgical removal of the adrenal gland) is a major procedure with significant risks, and is not the first-line management for a 3cm adrenal mass incidentally found on a CT scan. Imaging studies (e.g., CT, MRI, or ultrasound) and clinical evaluation are usually employed to determine the nature of the mass before considering such a major procedure.

**Clinical Pearl:**
In cases of adrenal masses incidentally detected on imaging studies, a stepwise approach is adopted to evaluate and manage the condition. This includes obtaining detailed clinical history, physical examination, imaging studies (e.g., CT, MRI, or ultrasound), and biochemical and hormonal evaluation. Only after thorough evaluation is a decision made regarding further management, such as adrenal biopsy, adrenal venous sampling, or adrenalectomy.

In this case, adrenal venous sampling and adrenal biopsy are invasive procedures that should be reserved for specific cases, while adrenalectomy is a major procedure with significant risks, and should only be considered following thorough imaging evaluation and biochemical/hormonal testing. As a 3cm adrenal mass is usually benign in nature, a stepwise approach is adopted to manage the condition.