Sellar germinoma mimicking IgG4-related hypophysitis: a case report.

Abstract

BACKGROUND:

The differential diagnosis of IgG4-related hypophysitis and other inflammatory diseases or tumors involving sellar region is challenging even after sellar biopsy. Sellar germinoma is usually infiltrated by lymphocytes or plasma cells, and may be confused with hypophysitis.

CASE PRESENTATION:

A 36-year-old man with diabetes insipidus, elevated serum IgG4 level (336 mg/dl), and sellar mass was suspected to have IgG4-related hypophysitis, and no other lesion of IgG4-related disease was detected. After treated by prednisone and mycophenolate mofetil, the serum IgG4 decreased to 214 mg/dl. However, after withdrawal of the drugs, the IgG4 level increased to 308 mg/dl. Endocrine assessments revealed panhypopituitarism, and the sellar mass enlarged. Transsphenoidal sellar exploration and biopsy was conducted. Pathological examination showed that the lesion was germinoma with lymphocytes and plasma cells infiltration, and IgG4-staining was positive (70/HPF, IgG4/IgG ratio = 10%). The patient was then treated by cisplatin and etoposide. After four cycles of chemotherapy, the serum IgG4 was 201 mg/dl, and the sellar mass was invisible.

CONCLUSION:

Sellar germinoma can mimic the clinical characteristics of IgG4-related hypophysitis. Poor response to glucocorticoids can be used as an exclusion criterion in the clinical diagnosis of IgG4-related hypophysitis.

• Authors: Kang Chen, Yong Yao, Xinxin Mao, Hui You, Linjie Wang, Lian Duan, Kan Deng, Wen Zhang, Xin Lian, Huijuan Zhu
• Journal: BMC endocrine disorders (BMC Endocr Disord) Vol. 22 Issue 1 Pg. 23 (Jan 15 2022) ISSN: 1472-6823 [Electronic] England
• PMID: 35033046 (Publication Type: Case Reports, Journal Article)
• Copyright: © 2022. The Author(s).

Chemical References

• Immunoglobulin G
• Etoposide
• Cisplatin

Topics

• Adult
• Antineoplastic Combined Chemotherapy Protocols (therapeutic use)
• Autoimmune Hypophysitis (diagnosis)
• Brain Neoplasms (diagnosis, drug therapy)
• Cisplatin (administration & dosage)
• Diagnosis, Differential
• Etoposide (administration & dosage)
• Germinoma (diagnosis, drug therapy)
• Humans
• Immunoglobulin G (blood)
• Male
• Sella Turcica