18F-FDG PET/CT characteristics of pulmonary sclerosing hemangioma vs. pulmonary hamartoma

Abstract

The radiological features of pulmonary sclerosing hemangioma (PSH) and pulmonary hamartoma are poorly specified. Thus, the present study aimed to compare and analyze the characteristics of fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in PSH versus pulmonary hamartoma. ¹⁸F-FDG PET/CT characteristic findings of 12 patients with PSH and 14 patients with pulmonary hamartoma were retrospectively reviewed. A total of 12 lesions were detected from the 12 patients with PSH, of which 3 masses exhibited calcification. The mean diameter and standardized maximum uptake value (SUVmax) were 1.9±0.7 cm and 2.6±1.0, respectively, and there was no significant correlation between the lesion size and SUVmax (P>0.05). For the 14 patients with pulmonary hamartoma, 14 lesions were found, of which 4 exhibited calcification. The mean diameter and SUVmax were 1.7±0.8 cm and 1.5±0.6, respectively, and there was a significant correlation between the size and SUVmax (r=0.625, r²=0.391, P<0.05). Although there was no significant difference between the size of PSH and pulmonary hamartoma (P>0.05), the SUVmax of PSH was significantly higher than that of pulmonary hamartoma (P<0.05). Moreover, the SUVmax of 1.95 was applied as a cutoff for the diagnosis of PSH, and the resulting sensitivity and specificity for PET/CT to differentiate PSH from pulmonary hamartoma were 83.3 and 78.6%, respectively. Although the morphological features were not specific, PSH showed significantly higher FDG accumulation than pulmonary hamartoma on PET/CT imaging, which may aid the differential diagnosis. Further studies with larger populations are warranted to confirm these study results.

Keywords: fluorodeoxyglucose; positron emission tomography/computed tomography; pulmonary hamartoma; pulmonary sclerosing hemangioma.

Figure 1.

(A) Pearson's correlation and linear regression analysis showed no correlation between the tumor size and the SUVmax of PSH (P>0.05, r=0.560, r²=0.314). (B) Pearson's correlation and linear regression analysis determined a positive correlation between the tumor size and the SUVmax of pulmonary hamartoma (P<0.05, r=0.625, r²=0.391). PSH, pulmonary sclerosing hemangioma; SUVmax, maximum standardized uptake value.

Figure 2.

Representative case of a 47-year-old woman who underwent fluorodeoxyglucose PET/CT examination to evaluate a pulmonary nodule of the left lower lobe. (A) The maximum intensity projection image did not show the lesion, which was hidden behind the heart. On the axial images of the chest [(B) PET; (C) mediastinal window of CT; (D) fused PET/CT; (E) lung window of CT)], a round lesion (arrow) was present, with a maximum standardized uptake value of 4.4 and a size of ~2.5×2.4 cm. The pathology confirmed pulmonary sclerosing hemangioma. PET, positron emission tomography; CT, computed tomography.

Figure 3.

Representative case of a 55-year-old woman who underwent fluorodeoxyglucose PET/CT examination to evaluate a pulmonary nodule of the right lower lobe. (A) The lesion was covered by the liver on the maximum intensity projection image. On the axial images of the chest [(B) PET; (C) mediastinal window of CT; (D) fused PET/CT; (E) lung window of CT)], a similar round lesion (arrow) was found. The maximum standardized uptake value was 2.6 and the maximum diameter was 2.2 cm. Finally, the pathology of the nodule confirmed pulmonary sclerosing hemangioma. PET, positron emission tomography; CT, computed tomography.

Figure 4.

Representative case of a 57-year-old man admitted to hospital due to a cough. A lobular mass of the right middle lung was revealed, which was possibly malignant. The patient underwent fluorodeoxyglucose PET/CT to evaluate the disease extent. The maximum standardized uptake value of the mass (arrow) was 2.2 and the maximum diameter was 3.0 cm on the axial images of the chest [(A) PET; (B) mediastinal window of CT; (C) fused PET/CT]. (D) The lung window of CT revealed obstructive pneumonia at the distal end of the lesion. The pathology confirmed a pulmonary hamartoma. PET, positron emission tomography; CT, computed tomography.

Figure 5.

A significant difference was found between the SUVmax of the 12 pulmonary sclerosing hemangiomas and the 14 pulmonary hamartomas (P<0.05). SUVmax, maximum standardized uptake value.

Figure 6.

Receiver operating characteristic analysis for determining the cutoff value of the SUVmax in the differential diagnosis of pulmonary sclerosing hemangiomas and pulmonary hamartomas. When the SUVmax of 1.95 was used as the cutoff value, the sensitivity and specificity were 83.3 and 78.6%, respectively. The area under the curve was 0.836 (standard error, 0.082; P=0.004; 95% confidence interval, 0.676–0.996).