Lipofibroadenoma with B1 thymoma: A case report of a rare thymic tumor

Thymic lipofibroadenoma: A case report

Lipofibroadenoma (LFA) is an epithelial tumor. It has been seen rarely in the thymus, and only a handful of cases have been reported. LFA is usually seen in the anterior mediastinum and is defined as a coalescence of epithelial thymic, adipose, and fibrotic tissue. We present a 30-year-old female who presented due to an unrelated traffic accident. An incidental mass was found in her left anterior superior mediastinum. After performing a complete excision, a histologic examination of the excised mass revealed it to be LFA of the thymus, which is extremely rare. The follow-up period was uneventful. LFA is a slow-growing benign tumor and is very similar to fibroadenoma of the breast. The etiology and clinical findings are yet to be well-defined. It was only seen in men in the prior cases. But recent cases, including this one, have also reported female patients. The tumor is mainly observed in the anterior mediastinum, which was also the case in our patient. The gold standard of diagnosis is pathologic examination. Our examination showed strands and nests of thymic parenchyma, including Hassall corpuscles, which separated fibro adipose tissue. Thymectomy is the treatment of choice. It can be performed by either video-assisted thoracic surgery or open surgery. We performed open surgery. The most important prognostic factor for this tumor is staging.

Thymic epithelial tumours: histopathological classification and differential diagnosis

The epithelial and lymphoid compartments of the thymus can give rise to a wide variety of tumours, including thymomas, thymic carcinomas, lymphoreticular proliferations, germ cell tumours, and sarcomas. While some of these have close similarity to their counterparts in other organs, both in terms of histology and immunohistochemistry, as well as molecular features, others are unique to the thymus. The epithelial tumours, which can develop in the thymus, will be discussed in this review, with a particular emphasis on resolving differential diagnosis by means of morphology, immunohistochemical profiles, and molecular diagnostics.

Thymic lipofibroadenomas: Three case reports

BACKGROUND

Thymic lipofibroadenomas are extremely rare. In this study, we investigated the clinicopathological characteristics of thymic lipofibroadenomas.

CASE SUMMARY

This study included three patients with thymic lipofibroadenomas. We retrospectively analyzed the patient data to determine the clinicopathological characteristics of thymic lipofibroadenomas. The study included one man and two women [mean age, 43 (33-59) years]. All patients were non-smokers and presented with well-defined anterior mediastinal tumors. The cut surfaces of the tumors were solid, with a mixture of yellow and white areas. Microscopic evaluation of resected specimens showed scattered cord-like structures of epithelial cells embedded within abundant fibrotic and hyaline stroma admixed with variable quantities of adipose tissue. One patient showed hyperplastic thymic tissue in a part of the tumor.

CONCLUSION

Thymic lipofibroadenomas are an extremely rare type of benign thymic tumor. Surgical removal of lipofibroadenomas is usually curative.

Thymic lipofibroadenoma of the anterior mediastinum: A rare case report

BACKGROUND

Lipofibroadenoma is an extremely rare thymic tumor, and the anterior mediastinum is the most common site.

CASE SUMMARY

A 21-year-old male was admitted with fever without obvious cause for 2 months. After admission, the patient's highest temperature was 38.3°C, accompanied by diarrhea. Physical examination showed coarse breath sounds in both lungs. Chest enhanced computed tomography (CT) showed a mass of mixed density shadow on the left side of the anterior mediastinum with a size of approximately 9.2 cm × 5 cm × 2.1 cm and a clear boundary mixed with a low fat density shadow. Mediastinal tumors were removed under general anesthesia by video-assisted thoracoscopic surgery. Macroscopically, a clear boundary was shown between the tumor and the remaining thymus. Microscopically, the tumor contained a large amount of mature adipose and fibrous tissue with scattered cord-like epithelial tissue and a small number of lymphocytes scattered in the stroma. The tumor lacked thymic bodies. The neoplastic epithelial cells were oval or polygonal and arranged in fissures, the nuclei were uniform in size and mild in shape, and mitosis was rare. Epithelial cells were positive for AE1/AE3 and CK19, lymphocytes were positive for CD3 and CD20, and fat and fibrous tissue were positive for S-100 and vimentin, respectively. The Ki67 labeling index was less than 5%. Based on histological features and immunophenotype, thymic lipofibroadenoma was diagnosed. The patient was followed up 1 year after the operation, and no recurrence or residual lesions were found on the X-ray re-examination.

CONCLUSION

Lipofibroadenoma is a benign thymic tumor, and thymectomy is regarded as the best treatment. The biological behavior of thymic lipofibroadenoma is good, and the recurrence rate is low.

Thymofibrolipoma: a case report and review of the literature

Background

Thymofibrolipoma has been described as a variant of thymolipoma. To date, 3 cases have been reported, and the lesion have been described to consist of extensive areas of collagenous tissue interspersed with islands of mature adipose tissue and strands of thymic tissue.

Case presentation

A 43-year-old woman had an anterior mediastinal tumor. Macroscopically, the cut surface of the tumor was composed of a yellowish lipomatous component and a uniform whitish fibrous component with elastic stiffness. Microscopically, the tumor was composed of collagenous fibrous tissue with sparse spindle cells, mature adipocytes and strands or islands of thymic tissue. The spindle cells in the fibrous tissue had monoallelic deletion of the 13q14 region and corresponding loss of RB1 and FOXO1A protein expression.

Conclusions

This case report may strengthen the hypothesis that thymofibrolipoma is a neoplastic lesion and a variant of thymolipoma and that thymofibrolipoma and lipofibroadenoma are different names for the same lesion. The name “lipofibroadenoma” was given to the lesion because of its histological resemblance to fibroadenoma of the mammary gland. However, this name does not reflect the pathogenesis of this lesion, and the name “thymofibrolipoma” would be preferable. It will be necessary to discuss whether lipofibroadenoma should be listed as an independent entity in the WHO classification.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-022-01260-1.

Giant Intrathoracic Mass in a Young Woman With Acute Kidney Injury

CASE PRESENTATION

A 35-year-old woman without past medical history sought treatment for fatigue and dry cough of 3 weeks' duration. Basic laboratory tests revealed severe anemia. She had no history of bleeding, hemoptysis, dyspnea, or fever. The patient was admitted for RBC transfusion and more extensive diagnostics.

Thymic lipofibroadenoma accompanied with largish calcifications

Thymic lipofibroadenomas are extremely rare; their radiological features have never been reported. We report the first case of a lipofibroadenoma with some largish calcifications mimicking a teratoma. A 28-year-old man had an anterior mediastinal tumor with some calcifications on preoperative computed tomography, which was suspected to be a mature teratoma and resected through robot-assisted thoracic surgery. This tumor had strands of epithelial cells separated by abundant fibrous stroma containing fat cells and was thus diagnosed as a lipofibroadenoma. He was well without any recurrence 6 months postoperatively. Largish calcifications on preoperative computed tomography make distinguishing between teratomas and lipfibroadenomas difficult.