Spindle-cell hibernoma: a very rare mediastinal tumor


Hippokratia 2017, 21(4):205

Erşen E, Kılıç B, Alizade N
Department of Thoracic Surgery, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey

Key words: Mediastinum, hibernoma, spindle-cell, thoracoscopy

Corresponding author: Ezel Erşen, Istanbul University Cerrahpasa Medical Faculty, Department of Thoracic Surgery, Kocamustafapasa/Fatih Istanbul, 34303 Turkey, tel: +00902124143590, fax: +00902126328474, e-mail: drezelersen@gmail.com

Dear Editor,

A 42-year-old female was admitted to our clinic with persistent cough and dyspnea. Her chest x-ray showed considerable enlargement of the mediastinum (Figure 1A), involving mainly the right side of the chest. Computed tomography (CT) revealed a homogeneous mass with dimensions 5.1 x 5.3 x 5.9 cm at the right paratracheal region (Figure 1B). The exact nature of the mass – i.e. whether it was cystic or solid – could not be determined. As the patient had claustrophobia, she refused performing magnetic resonance imaging (MRI). Transbronchial biopsy was non-contributory. Since it was not possible to complete the resection with mediastinoscopy, we decided to perform videothoracoscopy. An encapsulated brownish white mass was removed from the mediastinum. The postoperative course was uneventful, and the patient was discharged on the second postoperative day. Histologic examination of the specimen revealed “hibernoma” with proliferation of small bland spindle-cells. Immunohistochemically, cells were positive for the CD34 and S-100 proteins.

Figure 1: A) Chest x-ray of the 42-yearold woman showing an enlargement of the mediastinum. B) Axial computed tomography scan of her chest reveals a homogeneous mass at the right paratracheal region, extending towards the mediastinum.

Hibernoma was first described by Merkl in 1906 and was named as “hibernoma” by Gery due to its morphologic similarity with hibernating glands of the animals1. Most of the patients are asymptomatic, but symptoms such as cough, dyspnea, and hoarseness may be observed2. Hibernomas appear on CT and MRI similarly with other fibrous and lipomatous tumors. Even with the advanced imaging techniques, malignancy cannot be excluded in most cases. There are also reports that yield positive positron-emission tomography (PET)-CT scans3. Review of the literature reveals only nine reported cases of mediastinal hibernomas – including our case4. It is difficult to distinguish spindle-cell tumors from myxoid liposarcoma5. Our case is the first case including mediastinal hibernoma with a spindle-cell component. Resection of the tumor relieved the patient’s symptoms, and there has been no recurrence for the last three years.

Conflict of interest

Authors declare no conflict of interest.


1. Beals C, Rogers A, Wakely P, Mayerson JL, Scharschmidt TJ. Hibernomas: a single-institution experience and review of literature. Med Oncol. 2014; 31: 769.
2. Barbetakis N, Asteriou C, Stefanidis A, Kynigou M. Mediastinal hibernoma presenting with hoarseness. Interact Cardiovasc Thorac Surg. 2011; 12: 845-846.
3. Burdick MJ, Jolles PR, Grimes MM, Henry DA. Mediastinal hibernoma simulates a malignant lesion on dual time point FDG imaging. Lung Cancer. 2008; 59: 391-394.
4. Moretti VM, Brooks JS, Lackman RD. Spindle-cell hibernoma: a clinicopathologic comparison of this new variant. Orthopedics. 2010; 33: 52-55.
5. La Mantia E, Franco R, Rocco R, Rocco G. Spindle cell lipoma: a rare tumor of the mediastinum. J Thorac Dis. 2013; 5: 152-154.