[Malignant thymoma with polymorphic exanthema and erosive mucous membrane changes].

Area of Science:

• Immunology
• Oncology
• Dermatology

Background:

• Polymorphous exanthema and mucosal erosions can be challenging to treat.
• Malignant thymoma is a rare tumor of the thymus gland.

Observation:

• A 30-year-old female presented with therapy-refractory polymorphous exanthema and severe oral and genital erosions.
• Skin and mucosal lesions were associated with a malignant thymoma with metastases.
• Extensive autoantibodies were detected without clear clinical correlation.

Findings:

• The patient's condition was interpreted as a paraneoplastic syndrome secondary to malignant thymoma.
• Examination revealed immune dysregulation, specifically between cellular and humoral immunity.
• An uncontrolled, extraordinary antibody production against self and non-self structures was observed.

Implications:

• This case highlights a rare presentation of thymoma-associated paraneoplastic syndrome.
• Understanding the immune dysregulation is crucial for managing such complex cases.
• Further research into thymoma-related autoimmunity may improve patient outcomes.