Ann Thorac Surg 2006;81:2287-2289
© 2006 The Society of Thoracic Surgeons
Case report
Rapidly Growing Endobronchial Hamartoma With Bone Marrow Tissue
Hisashi Oishi, MD
a
,
*
,
Toshiharu Tabata, MD
a
,
Yoshinori Okada, MD
a
,
Mareyuki Endo, MD
b
,
Satoshi Suzuki, MD
a
,
Yuji Matsumura, MD
a
,
Takashi Kondo, MD
a
a Department of Thoracic Surgery, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
b Department of Pathology, Tohoku University Hospital, Sendai, Japan
Accepted for publication July 25, 2005.
* Address correspondence to Dr Oishi, Department of Thoracic Surgery, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-machi, Aoba-ku Sendai, 980-8575 Japan (Email: bigstone{at}idac.tohoku.ac.jp).
 |
Abstract
|
|---|
A 29-year-old woman presented with a 4 x 3.5 cm circumscribed mass located in the left upper lobe, which had not been detected in a chest roentgenogram that was taken 3 years prior. Bone scintigraphy using technetium-99m methylene diphosphonate revealed an increased uptake of the isotope in the mass, indicating increased osteoplastic activity. She underwent surgical resection of the mass and the pathologic diagnosis was endobronchially located pulmonary hamartoma, which contained bone marrow tissue. An extremely rare case of pulmonary hamartoma showing rapid growth and involving bone marrow tissue is presented.
|
Introduction
|
|---|
Pulmonary hamartomas are common benign tumors; the majority of these grow slowly [1–3]. Pathologically the tumors are mainly composed of cartilage, fat, fibrous tissue, and bone [2, 3]. Here we describe a rare case with pulmonary hamartoma that showed rapid growth. Moreover the tumor contained bone marrow tissue, which is not usually observed in pulmonary hamartomas.
A 29-year-old woman with no symptoms was referred to us because of an abnormality on a chest roentgenogram examination. Her chest roentgenogram at a health examination 3 years prior had been normal, and no roentgenograms had been available thereafter until this time. A chest roentgenogram and a computed tomographic chest scan on admission demonstrated a 4 x 3.5 cm well circumscribed mass, including dense calcifications located in the left upper lobe (Fig 1). The tumor was primarily suspected to be a pulmonary hamartoma with a slight possibility of metastasis of a primary bone tumor, which led us to a systemic investigation. Positron emission tomography showed a slightly increased uptake in the pulmonary lesion with no other abnormalities. Bone scintigraphy using technetium-99m methylene diphosphonate revealed an increased uptake of the isotope in the pulmonary lesion (Fig 2). A bronchoscopic examination revealed a hard polypoidal mass with smooth surface in B1+2a; however, we could not obtain enough specimen for a histologic diagnosis due to its smooth and hard surface.
View larger version (55K):
[in this window]
[in a new window]
|
Fig 1. Chest computed tomographic scan shows a 4 x 3.5 cm circumscribed pulmonary mass (including dense focal calcification) located in the left upper lobe.
|
|
View larger version (68K):
[in this window]
[in a new window]
|
Fig 2. Bone scintigraphy (technetium-99m methylene diphosphonate bone scintigraphy) shows a strong accumulation in the lung (ie, in the right upper lobe).
|
|
Because of a relatively large tumor size with a marked growth within 3 years, and an anxiety with a potential of obstructive pneumonia in the future, the patient was offered surgery and underwent an upper divisionectomy through a left posterolateral thoracotomy. Macroscopically the tumor was well circumscribed and hard. Microscopically the tumor arose from a peripheral bronchus obstructing the lumen of more central bronchi and was mainly composed of hyaline cartilage, osteoid, and bone. It is noteworthy that the tumor also contained bone marrow tissue (Fig 3). Pathologic diagnosis was an endobronchially located pulmonary hamartoma. The patient's postoperative course was uneventful, and she was discharged on postoperative day 15. The patient is well with no evidence of recurrences at her 1-year follow-up.
View larger version (120K):
[in this window]
[in a new window]
|
Fig 3. (A) The tumor is mainly composed of hyaline cartilage and osteoid, partially included bone and bone marrow. (Hematoxylin and eosin; x 100.) (B) The myeloid elements are observed, such as true bone marrow. (Hematoxylin and eosin; x 400.)
|
|
|
Comment
|
|---|
Pulmonary hamartoma is a benign tumor of the lung that grows very slowly [1–3]. In one study, tumors increased in size by an average of 3.2 mm per year [1]. On marked contrast, the tumor in the present case had grown in size to 4 cm in diameter within as much as 3 years. The tumor showed dense calcifications in the computed tomographic scan and a characteristic roentgenographic feature was a markedly increased uptake in the technetium-99m methylene diphosphonate bone scintigraphy. An osteoblastic activity is known to be the major factor determining the intensity of uptake of technetium-99m methylene diphosphonate in the bone scintigraphy [4], and marked ossification possibly due to an increased osteoblastic activity in the tumor might explain the rapid-growing nature of the tumor in the present case. However, unfortunately we were not able to ascertain this hypothesis because only few reports were available that describe the findings of bone scintigraphy in pulmonary hamartomas [4, 5].
In addition to the clinical characteristics previously mentioned, the tumor showed an unusual finding in the histologic examination (ie, it contained bone marrow tissue). In the spaces between the bone spicules, the myeloid elements of bone marrow, mature adipose tissue, and many hematopoietic cells were observed as in usual bone marrow. In the bone spicules, many osteoblasts are observed indicating increased osteoblastic activity. Reports of bone marrow involvement in pulmonary hamartoma are extremely rare [2], although pulmonary hamartomas are now generally believed to be benign neoplasms that are probably derived from bronchial wall mesenchymal cells that have a potential to differentiate to hematopoietic cells.
In summary, we report a rare case of pulmonary hamartoma that grew rapidly and contained bone marrow tissue. Therefore we caution colleagues to adequately follow-up patients with clinically diagnosed pulmonary hamartomas.
|
References
|
|---|
- Hansen CP, Holtveg H, Francis D, Rasch L, Bertelsen S. Pulmonary hamartoma J Thorac Cardiovasc Surg 1992;104:674-678.[Abstract]
- Cagle Philip T. Pathology of the lung tumors of the lungIn: Thurlbeck WM, Churg AM, editors. Pathology of the lung. 2nd ed.. New York, NY: Thieme Medical Publishers; 1995. pp. 437-551.
- Cosio BG, Villena V, Echave-Sustaeta J, et al. Endobronchial hamartoma Chest 2002;122:202-205.[Abstract/Free Full Text]
- Burke W, Rubens MB. Uptake of technetium-99m methylene diphosphonate by a pulmonary hamartoma/mesenchymoma Br J Radiol 1993;66:74-76.[Medline]
- Schechter LS. Tc-99m methylene diphosphonate accumulation by a pulmonary hamartoma Clin Nucl Med 1998;23:695-696.[Medline]
Top
Abstract
Introduction
