Incidental pheo (?) found by DOTATATE PET

Whenever a new imaging method is used widely, incidental findings from it are encountered. The new Ga-68 DOTATATE PET is no exception. It is well known that DOTATATE signals are normally found in the pituitary, salivary glands, thyroid, liver, spleen, and adrenal glands. Some people may also have signals in the pancreas.
      Although the adrenal glands are known to be lit up by DOTATATE PET, the signal from normal adrenal glands is usually low. A technical jargon called the standard uptake value (SUV) quantitatively describes the intensity of PET signals. Unfortunately, different machines give out different SUVs on the same organ of the same patient. The SUV thus has relative importance only in the same patient using the same machine.
      I saw a patient recently. She had another kind of neuroendocrine tumor and did a DOTATATE PET. The PET showed she had strong signal on one adrenal gland (SUV ~8) while the other adrenal gland had normal signal (SUV ~2). CT showed a tiny nodule in the adrenal gland with strong PET signal. Is this a metastatic lesion of the other neuroendocrine tumor? Or is it a tiny pheo that is incidentally found by the DOATATE PET? Either adrenal metastasis from neuroendocrine tumor or pheo is rare. Based on a variety of factors, I favor she has a tiny pheo. There are no convincing ways to prove either diagnosis. Only time will tell.

Dr. Pheo