Radiation Exposure from GEP NET Surveillance

Area of Science:

• Oncology
• Radiology
• Medical Physics

Background:

• Neuroendocrine tumors (NET) are neoplasms with peptide/neuroamine secretion.
• Surgical resection is the only curative treatment for gastroenteropancreatic (GEP) NET.
• Long surveillance is recommended for GEP NET due to late recurrence.

Purpose of the Study:

• To evaluate radiation exposure from surveillance practices in completely resected GEP NET.
• To analyze imaging modalities and duration of follow-up in GEP NET surveillance.
• To assess cumulative effective radiation doses during GEP NET follow-up.

Main Methods:

• Retrospective cohort study of well-differentiated GEP NET cases (2005-2020).
• Data collected on primary tumor location, imaging modality, and follow-up duration.
• Dosimetry data used to calculate effective radiation doses.

Main Results:

• 62 cases and 422 surveillance scans were analyzed.
• Cross-sectional imaging dominated surveillance (82%).
• Mean total effective dose over 10 years was estimated at 106 mSv, with annual mean of 10.62 mSv.

Conclusions:

• Post-resection surveillance of GEP NET results in substantial cumulative radiation doses.
• These doses are within the range associated with secondary malignancy risk.
• Future guidelines should incorporate strategies to minimize radiation exposure during surveillance.