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Intraosseous Lipoma of the Rib
IMAGES
FIGURE 1.
IN THE
MEDICAL SCIENCES
FIGURE 2.
Intraosseous Lipoma of the Rib
A
49-year-old woman complained of intermittent chest pain for 6 months. On physical examination, there was local swelling and a fixed tumor at the lateral right hemithorax. Laboratory tests were noncontributory. Chest computed tomography revealed a low-density expansile mass overlying the right seventh and eighth ribs (Figure 1) and a lipomatous lesion (5 ⫻ 5 cm) within the seventh rib (Figure 2). Differential diagnosis included giant cell tumor, plasmacytoma, fibrous dysplasia, and enchondroma. Under general anesthesia, the patient underwent en bloc surgical resection of the right seventh and eighth ribs and intercostal muscles, revealing a cystic, lobulated tumor (7 ⫻ 8 cm) on the costal surface. Histopathological analysis showed mature fat cells without signs of calcification. Recovery was satisfactory, and there has been no recurrence. Intraosseous lipomas represent less than 0.1% of all primary bone tumors,1 and to the authors’ knowledge only 6 cases have been published in the literature.1,2 Nearly every bone can be affected, although favored sites are the calcaneus and the metaphysis of long bones.3 The occurrence of the tumor inside the bone trabecula suggests the origin from the bone marrow adipose tissue. Tumors most commonly arise in the fourth age decade with a slight male preponderance. About half of the patients present without symptoms.3 Diagnosis is usually made with classic radiographic features. In asymptomatic cases, a regular clinical and radiographic follow-up is the best option. Although intraosseous lipomas are generally considered benign, malignant transformation has been described in 5 cases and recurrence in 2 cases.3 When symptoms are present, treatment should consist of surgical excision. REFERENCES 1. Solak O, Esme H, Sahin DA, et al. Giant intraosseous lipoma of the rib. Thorac Cardiovasc Surg 2007;55:273– 4. 2. Mardi K, Sharma J. Intraosseous angiolipoma of the rib. Indian J Pathol Microbiol 2007;50:606 –7. 3. Radl R, Leithner A, Machacek F, et al. Intraosseous lipoma: retrospective analysis of 29 patients. Int Orthop 2004;28:374 – 8.
Ozgur Katrancioglu, Feride Sapmaz, Tanseli E. Gonlugur, Sahande Elagoz, Corresponding Author: Ugur Gonlugur,
MD MD MD MD MD
Canakkale Onsekiz Mart University Medical School Canakkale, Turkey E-mail: [email protected]
The American Journal of the Medical Sciences • Volume 337, Number 2, February 2009
131
FIGURE 1.
IN THE
MEDICAL SCIENCES
FIGURE 2.
Intraosseous Lipoma of the Rib
A
49-year-old woman complained of intermittent chest pain for 6 months. On physical examination, there was local swelling and a fixed tumor at the lateral right hemithorax. Laboratory tests were noncontributory. Chest computed tomography revealed a low-density expansile mass overlying the right seventh and eighth ribs (Figure 1) and a lipomatous lesion (5 ⫻ 5 cm) within the seventh rib (Figure 2). Differential diagnosis included giant cell tumor, plasmacytoma, fibrous dysplasia, and enchondroma. Under general anesthesia, the patient underwent en bloc surgical resection of the right seventh and eighth ribs and intercostal muscles, revealing a cystic, lobulated tumor (7 ⫻ 8 cm) on the costal surface. Histopathological analysis showed mature fat cells without signs of calcification. Recovery was satisfactory, and there has been no recurrence. Intraosseous lipomas represent less than 0.1% of all primary bone tumors,1 and to the authors’ knowledge only 6 cases have been published in the literature.1,2 Nearly every bone can be affected, although favored sites are the calcaneus and the metaphysis of long bones.3 The occurrence of the tumor inside the bone trabecula suggests the origin from the bone marrow adipose tissue. Tumors most commonly arise in the fourth age decade with a slight male preponderance. About half of the patients present without symptoms.3 Diagnosis is usually made with classic radiographic features. In asymptomatic cases, a regular clinical and radiographic follow-up is the best option. Although intraosseous lipomas are generally considered benign, malignant transformation has been described in 5 cases and recurrence in 2 cases.3 When symptoms are present, treatment should consist of surgical excision. REFERENCES 1. Solak O, Esme H, Sahin DA, et al. Giant intraosseous lipoma of the rib. Thorac Cardiovasc Surg 2007;55:273– 4. 2. Mardi K, Sharma J. Intraosseous angiolipoma of the rib. Indian J Pathol Microbiol 2007;50:606 –7. 3. Radl R, Leithner A, Machacek F, et al. Intraosseous lipoma: retrospective analysis of 29 patients. Int Orthop 2004;28:374 – 8.
Ozgur Katrancioglu, Feride Sapmaz, Tanseli E. Gonlugur, Sahande Elagoz, Corresponding Author: Ugur Gonlugur,
MD MD MD MD MD
Canakkale Onsekiz Mart University Medical School Canakkale, Turkey E-mail: [email protected]
The American Journal of the Medical Sciences • Volume 337, Number 2, February 2009
131