Occasional detection of thymic epithelial tumor 4 years after diagnosis of adult onset Still disease: A challenging case report and immuno-oncological considerations coming from pertinent literature review.
BACKGROUND
Thymoma is a T cell neoplasm arising from the thymic epithelium that due to its immunological role, frequently undercover derangements of immunity such a tumors and autoimmune diseases.


METHODS
Herein, we report, to the best of our knowledge, the first description of an association between thymoma and adult onset Still disease (AOSD) in a 47-year-old man. The first one was occasionally detected 4 years later the diagnosis of AOSD, and surgically removed via right lateral thoracotomy. Histology confirmed an encapsulated thymic tumor (type AB sec. WHO-classification).


RESULTS
The AOSD was particularly resistant to the therapy, requiring a combination of immunosuppressant followed by anti-IL1R, that was the only steroids-sparing treatment capable to induce and maintain the remission. The differential diagnosis was particularly challenging because of the severe myasthenic-like symptoms that, with normal laboratory tests, were initially misinterpreted as fibromyalgia. The pathogenic link of this association could be a thymus escape of autoreactive T lymphocytes causing autoimmunity.


CONCLUSIONS
Clinicians should be always include the possibility of a thymoma in the differential diagnosis of an unusual new onset of weakness and normal laboratories data, in particular once autoimmune disease is present in the medical history.
Unit of Thoracic Surgery, Arcispedale Santa Maria Nuova-IRCCS Rheumatology Unit, Arcispedale Santa Maria Nuova-IRCCS Unit of Pathology, Arcispedale Santa Maria Nuova-IRCCS, Reggio Emilia, Italy.
Filippo
F
Lococo
Gianluigi
G
Bajocchi
Andrea
A
Caruso
Riccardo
R
Valli
Tommaso
T
Ricchetti
Giorgio
G
Sgarbi
Carlo
C
Salvarani
D006801:Humans; D008297:Male; D008875:Middle Aged; D016706:Still's Disease, Adult-Onset / Q000150:complications*; D013945:Thymoma / Q000276:immunology*; D013953:Thymus Neoplasms / Q000276:immunology*