대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Kaposi Sarcoma

Radiologic Findings

Fig. 1. Chest posteroanterior radiograph showing reticulonodular opacities in both lungs.
Figs. 2 and 3. Computed tomography (CT) scans showing tiny (< 5 mm) ill-defined nodules along the bronchovascular bundle with interstitial infiltration in both lungs without zonal predominance.
Figs. 4–6. CT scans after 9 months showing increased extent of ill-defined nodules with aggravation of shaggy interstitial thickening in both lungs.

Brief Review

The patient underwent bronchoscopic biopsy of the right lower lobe, and the histopathologic evaluation showed a spindle cell lesion with human herpesvirus 8 (HHV-8) positivity, suggesting Kaposi sarcoma (KS). The patient also had cutaneous involvement of KS in the eyelid, appearing as a nodular, red-purple elevated skin lesion.
KS is a low-grade vascular tumor that typically manifests as one of four variants: classic KS, endemic (African) KS, iatrogenic (organ transplant-related) KS, or acquired immunodeficiency syndrome (AIDS)-related KS. Classic KS and endemic KS rarely require radiologic evaluation because of the usually chronic course and stable skin compromise. However, iatrogenic KS and AIDS-related KS, the most common forms of the disease, are frequently disseminated or symptomatic and may require imaging studies for both diagnosis and staging. HHV-8 (or KS-associated herpesvirus) and other cofactors (e.g., cytokine-induced growth) have been linked to the development of KS. In a study of 8724 de novo malignancies in recipients of organ allografts, iatrogenic KS had a prevalence of 5.7%, with a mean development time of 21 months. Approximately 60% of patients developed nonvisceral KS confined to the skin, conjunctiva, or oropharyngeal mucosa, whereas 40% had visceral disease (i.e., involvement of the gastrointestinal tract, lungs, lymph nodes, and other visceral organs). In pulmonary KS, a characteristic finding on computed tomography is the presence of bilateral and symmetric ill-defined nodules in a peribronchovascular distribution, some of which can exhibit coalescence and progress to consolidation. Ground-glass opacities may be seen surrounding the nodules (“halo sign”). Further, axial interstitial/interlobular septal thickening, fissural nodularities, and mediastinal lymphadenopathy pleural abnormalities are also common.

Please refer to

Case 461,

KSTR Imaging Conference 2015 Spring  Case 8,

References

1. Restrepo CS, Martínez S, Lemos JA et al. Imaging manifestations of Kaposi sarcoma. Radiographics. 2006;(4): 1169-85.
2. Penn I. Sarcomas in organ allograft recipients. Transplantation 1995;60:1485–1491.
3. Hartman TE, Primack SL, Muller NL, Staples CA. Diagnosis of thoracic complications in AIDS: accuracy of CT. AJR Am J Roentgenol 1994;162:547–553.

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