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Updated: May 21, 2026
07:43
Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas
Published on: January 17, 2018
A 28 year old lady with a pituitary mass
Brain Pathology (Zurich, Switzerland)
|June 16, 2012
Summary
This study reports an atypical pituitary adenoma featuring lymphocyte infiltration and germinal centers, a novel finding. Accurate diagnosis requires correlating histology with immunohistochemistry to distinguish it from similar pituitary lesions.
Area of Science:
- Endocrinology
- Pathology
- Oncology
Background:
- Pituitary adenomas are common tumors, but atypical variants with significant immune cell infiltration are rare.
- Understanding the histological spectrum of pituitary adenomas is crucial for accurate diagnosis and patient management.
Observation:
- A case of atypical pituitary adenoma demonstrated unusual histological features, including prominent lymphocyte infiltration and germinal center formation.
- Tumor cells were large and pleomorphic with vesicular nuclei and eosinophilic cytoplasm.
- Immunohistochemistry confirmed the presence of both T lymphocytes (CD3+) and B-cells (CD20+), forming germinal centers.
Findings:
- The pituitary adenoma exhibited features distinct from typical adenomas, notably the presence of germinal centers.
- The Ki-67 proliferation index was 15%, with rare mitoses observed.
- The extensive lymphocytic infiltrate included both T and B lymphocytes.
Implications:
- The presence of germinal centers in pituitary adenomas is a previously unreported finding.
- Distinguishing this entity from other pituitary lesions like germinoma and lymphocytic hypophysitis is critical.
- Correlating histological findings with immunohistochemistry is essential for precise diagnosis of pituitary tumors.
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