E4785. Thoracic Extranodal Involvement of Lymphoma
Authors
SongA Seo;
No Affiliation
Soo-yeon Jeong;
No Affiliation
Youngsoo Soh;
No Affiliation
Hanlim Song;
No Affiliation
Soo yeon Kim;
No Affiliation
Mi Sook Lee;
No Affiliation
Background
While radiologists are familiar with lymphoma manifesting as nodal disease, extranodal lymphoma can present a diagnostic challenge due to considerable imaging overlap with other malignant and benign processes. Primary extranodal lymphoma is limited to an extranodal site and its adjacent lymph node group, but it often spreads more extensively. Secondary involvement is generally more prevalent than primary lymphoma. Thoracic extranodal lymphoma can affect the lung, pleura, chest wall, or breast, or manifest as primary effusion lymphoma. It is crucial to identify the presence of extranodal disease during the imaging of known lymphoma patients for accurate staging and treatment.
Educational Goals / Teaching Points
Lymphoma commonly exhibits secondary involvement beyond lymph nodes. Therefore, it is recommended to evaluate not only lymph nodes but also abnormalities in other thoracic organs for accurate staging of patients with known lymphoma.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
In our presentation of 11 cases of extranodal lymphoma with thoracic involvement, the imaging findings were as follows. In cases of secondary pulmonary lymphoma, the findings were similar to those of primary pulmonary lymphoma. Nodules, masses, masslike consolidation, ground-glass opacity are common and may cavitate. Pleural involvement was observed as pleural thickening or extrapleural soft tissue. In cases of chest wall involvement, large masses involving the sternum were observed. Breast involvement was observed as an ill-defined oval heterogeneous hypoechoic mass on ultrasound. Primary effusion lymphoma is a rare large B-cell non-Hodgkin lymphoma presenting as body cavity effusions without a detectable tumor mass. Infection of B-cells with human herpesvirus (HHV)-8 is the main pathogenesis and is required for a definitive diagnosis of primary effusion lymphoma.
Conclusion
Lymphoma commonly affects extranodal structures in the chest as secondary involvement. Extranodal lymphoma has considerable imaging overlap with other malignant and benign processes. Therefore, it is crucial to identify the presence of extranodal disease during the imaging of patients with known lymphoma for accurate staging and treatment.
