A Rare Thymic Tumor - Lipofibroadenoma - Always a Postoperative Surprise

Abstract

Background/aim: Thymic lipofibroadenoma is a benign growth of unknown etiology extremely rarely described in the literature, morphologically resembling lipofibroadenoma of the breast. The diagnosis is usually a postoperative surprise and is made by the anatomopathologist. Surgical resection is curative.

Case report: The presented case is the first reported in a woman, to date. The patient was successfully submitted to surgery and complete resection of the giant intrathoracic tumor was performed. The histopathological and immunohistochemical studies came to demonstrated the presence of a thymic lipofibroadenoma while the postoperative outcomes were favorable.

Conclusion: In cases presenting large intrathoracic tumors complete resection is able to provide a significant improvement of the general condition of the patient, as well as a chance for cure.

Keywords: Thymic lipofibroadenoma; resection; thymic rare tumor.

Figure 1. Thorax computer tomography (CT) scan, showing a huge lipomatous tumor occupying anterior mediastinum and the lower right hemithorax.

Figure 2. Resection specimen weighting 2.8 kg.

Figure 3. H&E staining (magnification ×4): Lipoma at the left field, fibroadenoma (arrowhead), residual thymus at the bottom right corner.

Figure 4. H&E staining (magnification ×10) of fibroadenoma: Strands of epithelium (arrowhead) embedded in a dense fibrotic stroma and scattered fat cells.

Figure 5. H&E staining (magnification ×40): Microscopic thymoma/nodular hyperplasia of thymic epithelium; a small nodule of epithelial cells is shown by the arrowhead.

Figure 6. Immunohistochemical studies demonstrating the presence of Cytokeratin AE1/AE3 at the level of epithelial cells (arrowhead), sustaining the diagnosis of lipofibroadenoma.