A 60-yr-old woman presented with osteoporosis and atraumatic fractures of the spine and ribs in our neurological hospital in Linz, Upper Austria. She had a clinical history of bipolar affective disorder and cognitive decline, but the actual medical problem was lumbar pain. Treatment for osteoporosis already included bisphosphonates, vitamin D, and calcium. Endocrine evaluation for secondary osteoporosis revealed low TSH (0.17 U/ml) under prophylactic levothyroxine treatment (75 g/d) for multinodular goiter and ACTH-dependent hypercortisolism. Clinical evaluation presented obesity (weight, 75 kg, for 150 cm height), arterial hypertension, and diabetes mellitus. ACTH was elevated at 106 pg/ml, whereas morning serum cortisol (22 g/dl) was still in the normal range. Cortisol measured in 24-h urine was highly elevated at 502 g/d (normal range, 40–158 g/d). Dexamethasone suppression test with 1, 4, and 8 mg failed to suppress either plasma ACTH or cortisol in serum and/or 24-h urine (ACTH, 45 pg/ml; and cortisol, 20 g/dl and 400 g/d in all tests). Brain magnetic resonance imaging showed mild cortical atrophy and did not present any alterations of the pituitary. Because petrosal sinus catheterization cannot be practiced in the federal state of Upper Austria, it was postponed. Whole body fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) was done in May 2009 for tumor screening to detect a possible ectopic source of ACTH. A single nodule of the right thyroid lobe proved to be FDG avid (Fig. 1). Additionally, CT detected a lesion of the right kidney with a diameter of 2 cm that did not accumulate FDG. Because a former thyroid evaluation in March 2009— practiced in a regional institute in the “Salzkammergut” in Upper Austria—had evaluated this FDG-avid lesion as a cold nodule by Technetium-scintiscan and fine-needle-aspiration had shown oncocytic transformation of thyrocytes, we recommended thyroid surgery as the next step. Calcitonin screening had been negative in the patient. Near-total resection of the thyroid took place in June 2009, histology revealed regressive goiter, and a malignant lesion was not detected. The suspicious nodule was