A possible association between ionizing radiation and pituitary adenoma: a descriptive study

Area of Science:

• Endocrinology
• Oncology
• Radiation Oncology

Background:

• Ionizing radiation is a known risk factor for various solid tumors, including brain tumors.
• However, a direct association between radiation exposure and pituitary adenoma (PA) has not been established.
• Pituitary gland's susceptibility to radiation-induced tumors is questioned.

Purpose of the Study:

• To investigate a potential association between past radiation exposure and the development of pituitary adenoma (PA).
• To evaluate the risk of PA in individuals treated with radiotherapy in childhood.

Main Methods:

• Retrospective review of approximately 4900 medical records of patients irradiated in childhood for tinea capitis.
• Utilized the Israel Cancer Registry for additional patient identification.
• Estimated average pituitary gland radiation dose at 0.56 grays with meticulous irradiation validation.

Main Results:

• Identified 16 patients who developed symptomatic PA after childhood radiotherapy.
• Observed a notably high rate of second primary tumors (25%) within the irradiated field among these patients.
• Clinical and demographic profiles of identified PA patients were consistent with existing literature.

Conclusions:

• The pituitary gland's immunity to radiation-induced tumors is unlikely given evidence for other intracranial and endocrine tumors.
• This preliminary observation supports the role of ionizing radiation in the pathogenesis of pituitary adenoma.
• Further research is warranted to confirm the association and understand the underlying mechanisms.