Reduced uptake pattern on ⁶⁸Ga‐DOTATATE‐scan may indicate necrosis predicting aggressive behavior in pheochromocytoma and paragangliomas (PPGLs)

Abstract

BackgroundPredicting malignancy among pheochromocytoma paragangliomas (PPGLs) remains a challenge, with only limited understanding of the clinical and molecular characteristics. It has been suggested that reduced avidity of a PPGL on 68Ga‐DOTATATE PET/CT could be a sign of not only altered metabolic activity, but also of increased biologic aggressiveness, possibly due to loss of SSTR‐expression.DesignRetrospective cohort review.Patients and MeasurementsThirty‐seven patients who underwent treatment for PPGL at a tertiary institution over the period 2010−2022, had their biochemical, radiological, and clinicopathological variables collected.ResultsFive of 37 (13%) patients (5 males) with a mean age of 42 years were found to have malignant PPGLs. The mean size of the tumors were 5.4 cm, with 4 located in the paraaortic area and 1 in right adrenal. Functional imaging with 68Ga‐DOTATATE PET/CT showed a mean SUVmax of 4.5. Four of 5 patients underwent open resection of the tumors under general anesthesia following preoperative alpha blockade with oral phenoxybenzamine. The mean PASS score of the excised tumors was 5.5 in keeping with biologically aggressive tumors, with evidence of necrosis. All but 1 patient had germline SDHB‐mutation (Deletion Exon 1). Postintervention after a mean follow‐up of 31 months, 2 of 5 (40%) patient developed spinal metastasis and 1 patients (25%) died of cardiac complications.ConclusionA non‐highly avid PPGL on DOTATE scan should be considered as possibly having necrosis of tumors indicating a more aggressive tumor‐biology. There might be a subgroup of patients in whom FDG‐PET scan should be considered to gain additional information.

Enhancing precision: A predictive model for 177Lu-DOTATATE treatment response in neuroendocrine tumors using quantitative 68Ga-DOTATATE PET and clinicopathological biomarkers

“…This implies, unlike surgical procedures, that disease burden is a critical factor representing preserved healthy tissue, and that in PRRT, the percentage of liver involvement is not a significant predictor, given that PRRT is well-tolerated and does not cause serious hepatic toxicity. Also, necrotic volumes of liver tumors identified in 68 Ga-PET, present in 18 (20%) cases, demonstrated a poor prognostic value, suggesting that tumor necrosis may indicate a more aggressive tumor biology 24 .…”

Endocrinology application of molecular imaging: current role of PET/CT

“…In addition, other PET tracers like [ 18 F]F-Fluorodopamine, [ 11 C]hydroxy-ephedrine and [ 11 C]epinephrine are currently undergoing clinical validation [69]. SSA PET tracers and other nuclear medicine techniques are used in certain cases, particularly when there are specific genetic mutations or tumor recurrence [70,71].…”