Mediastinal myelolipoma showing gradual enlargement over 9 years: a case report.
BACKGROUND
Myelolipoma is a rare benign tumor composed of mature adipose tissue and normal hematopoietic tissue. Although surgical resection has been recommended due to the potential of progressive enlargement, the natural history of mediastinal myelolipoma has not yet been described. Herein we report a surgically resected mediastinal myelolipoma showing gradual enlargement over a period of 9 years.


METHODS
A 70-year-old woman presented with a posterior mediastinal mass shadow detected by computed tomography (CT) examination. She had a medical history of sigmoidectomy for colon cancer 13 years previously. A CT scan showed a smooth, well-demarcated 2.8 × 2.1-cm paravertebral mass shadow, composed of a fat density area and a soft tissue density area, which showed gradual enlargement from a 1.6 × 1.0-cm nodule 9 years previously. This was not accompanied by chronic anemia or hematologic disease including thalassemia, and no abnormal accumulation was observed on bone marrow scintigraphy or fluoro-2-deoxyglucose positron emission tomography. With a clinical diagnosis of mediastinal myelolipoma, surgical resection was performed, and pathological examination confirmed the diagnosis.


CONCLUSIONS
We experienced a rare case with mediastinal myelolipoma showing gradual enlargement, with a tumor doubling time of 1,212 days.
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Tatsuaki
T
Hosaka
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Yoshinobu
Y
Hata
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Takashi
T
Makino
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Hajime
H
Otsuka
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Satoshi
S
Koezuka
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan.
Takashi
T
Azumi
Department of Surgical Pathology, Toho University School of Medicine, Tokyo, Japan.
Kozue
K
Ejima
Department of Surgical Pathology, Toho University School of Medicine, Tokyo, Japan.
Naobumi
N
Tochigi
Department of Surgical Pathology, Toho University School of Medicine, Tokyo, Japan.
Kazutoshi
K
Shibuya
Division of Chest Surgery, Toho University School of Medicine, Tokyo, Japan. aiyoda@med.toho-u.ac.jp.
Akira
A
Iyoda
D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008479:Mediastinal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D018209:Myelolipoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D049268:Positron-Emission Tomography; D020775:Thoracic Surgery, Video-Assisted; D014057:Tomography, X-Ray Computed
Case report; Mediastinal tumor; Myelolipoma; Video-assisted thoracoscopic surgery