Sex-differences in [⁶⁸Ga]Ga-DOTANOC biodistribution

Area of Science:

• Nuclear Medicine
• Radiopharmaceutical Imaging
• Somatostatin Receptor Imaging

Background:

• Factors influencing organ uptake of somatostatin receptor (SSTR)-targeting radiopharmaceuticals are not well understood.
• Understanding these factors is crucial for accurate interpretation of PET/CT scans using agents like [68Ga]Ga-DOTANOC.

Purpose of the Study:

• To investigate the influence of gender on [68Ga]Ga-DOTANOC uptake in various organs.
• To assess the impact of other clinical factors, including diabetes, age, and medications (PPIs, OADs), on [68Ga]Ga-DOTANOC uptake.

Main Methods:

• Retrospective analysis of 118 [68Ga]Ga-DOTANOC PET/CT scans.
• Assessment of Standardized Uptake Values (SUVmax and SUVmean) in the stomach, liver, spleen, kidneys, adrenal glands, and pancreas.
• Collection of clinical data including gender, age, diabetes status, and medication history (PPIs, OADs, SSAs).

Main Results:

• Female patients exhibited significantly lower [68Ga]Ga-DOTANOC uptake in the stomach, liver, adrenal glands, and kidneys compared to males.
• Diabetes and younger age (<50 years) were associated with significantly higher stomach uptake (SUVmax and SUVmean).
• Proton pump inhibitors (PPIs) minimally affected liver uptake, while oral antidiabetics (OADs) increased uptake in the stomach, spleen, and adrenal glands.

Conclusions:

• Gender, diabetes, and age are significant determinants of [68Ga]Ga-DOTANOC organ uptake.
• The influence of ongoing medications like PPIs and OADs on radiopharmaceutical uptake is less pronounced.
• These findings are important for the accurate interpretation of [68Ga]Ga-DOTANOC PET/CT imaging.