dromlakhani Evaluate for Malignancy Using Imaging in Adrenal Adenoma Patients With CT Density Greater Than or Equal to 10 Hounsfield Units or Pathology Consistent With Possible Carcinoma
STEP 1 — Gather Information
Collect history of adrenal adenoma (including prior pathology), confirm post‑adrenalectomy Cushing’s syndrome status, obtain latest non‑contrast adrenal CT Hounsfield unit measurement, and review any available pathology report for atypia or possible carcinoma.
STEP 2 — Rule In / Rule Out
If CT density ≥10 HU OR pathology report indicates possible carcinoma → proceed to imaging malignancy workup; otherwise → routine surveillance per follow‑up schedule (no malignancy‑focused imaging needed).
STEP 3 — Classify or Stratify
For positive triggers, classify lesion as indeterminate risk (CT density 10‑20 HU) or high suspicion (>20 HU, irregular margins, necrosis, or pathology suggestive of carcinoma) to guide intensity of imaging evaluation.
STEP 4 — Decide
If high‑suspicion features on dedicated adrenal protocol CT (washout <60%, size >4 cm, invasive growth) or MRI (chemical‑shift negative, irregular enhancement) → refer to endocrine oncology/surgical oncology for possible adrenalectomy, biopsy, or further staging; if indeterminate/low‑suspicion features → continue routine imaging surveillance every 6‑12 months.
Clinical Guardrails / Mimics / Pitfalls
Do not rely solely on non‑contrast CT density; lipid‑poor adenomas can mimic malignancy and require washout or chemical‑shift MRI for clarification. Avoid percutaneous biopsy without correlative imaging features that suggest malignancy. Do not overlook subtle pathology atypia; when in doubt, pursue multidisciplinary review.
Concrete Clinical Example
A 48‑year‑old woman with prior left adrenalectomy for Cushing’s syndrome (benign adenoma) presents with a right adrenal nodule on non‑contrast CT measuring 13 HU. Pathology from the resected adenoma showed no atypia. The lesion undergoes adrenal protocol CT with washout of 38% (indeterminate). Subsequent MRI shows lipid‑poor adenoma (signal loss on opposed‑phase). Patient continues routine surveillance with imaging every 12 months.
Source: Treatment of Cushing’s Syndrome: An Endocrine Society Clinical Practice Guideline, Nieman et al., 2015, DOI:10.1210/jc.2015-1818
TODO: consider adding scripts/calc.py for the es-cushing-evaluate-for-malignancy-high-ct-density-or-possible-carcinoma-adrenal-adenoma calculator