Figure 1
Chest AP
Plain chest radiograph shows complete opacifications of left lung, with contralateral shifting of mediastinal structure and trachea.
Anterior mediastinal mass consistent with primary mediastinal large B cell lymphoma
SectionChest imaging
Case TypeClinical Cases
AuthorsSuman Karki, MD
Connected authors
15 years, male
Clinical History
A 15-year-old male patient presented with a 3-months history of shortness of breath, decreased appetite, fatigue and fever. A chest radiograph revealed a massive left-sided pleural effusion. A chest tube was placed on the left hemithorax and the patient was sent to a referral centre.
Imaging Findings
A chest radiograph showed a complete opacification of the left hemithorax with a deviation of the trachea and the heart to the right.
Ultrasound of the left hemithorax showed a minimal loculated pleural effusion and an extensive heterogeneous mass within the left chest cavity.
Thoracic and abdominal computed tomography with and without IV contrast demonstrated a 16 x 13 x 10 cm heterogeneous enhancing anterior mediastinal mass lesion without fat or calcifications but areas of necrosis. The mediastinal structures and heart were displaced towards the right side. There was a compression atelectasis of the left lung, a minimal pleural effusion on the left side and a moderate pericardial effusion.
CT guided needle biopsy of the mass revealed a large B-cell lymphoma.
Ultrasound of the left hemithorax showed a minimal loculated pleural effusion and an extensive heterogeneous mass within the left chest cavity.
Thoracic and abdominal computed tomography with and without IV contrast demonstrated a 16 x 13 x 10 cm heterogeneous enhancing anterior mediastinal mass lesion without fat or calcifications but areas of necrosis. The mediastinal structures and heart were displaced towards the right side. There was a compression atelectasis of the left lung, a minimal pleural effusion on the left side and a moderate pericardial effusion.
CT guided needle biopsy of the mass revealed a large B-cell lymphoma.
Discussion
For anterior mediastinal masses, the classic differential diagnosis is the “4 Ts”; namely thymoma, thyroid, teratoma and terrible lymphoma.
Germ cell tumours are common in young adults and constitute 15% of all anterior mediastinal masses in adults. Histologically they are divided into benign teratomas, seminomas and embryonal tumours which are also known as malignant teratoma or non-seminomatous tumour [5].
75% of all mediastinal germ cell tumours are mature teratomas. Calcification, teeth, bone and/or fat in a lesion are indicative of a teratoma. Serum tumour markers, AFP, beta HCG are also helpful for the diagnosis of a germ cell tumour [4, 5]
Mediastinal lymphomas are common, either as part of a disseminated disease or less commonly as the site of primary origin. The mediastinum is commonly affected by systemic lymphomas. Only 10% of lymphomas which involve the mediastinum are primary and the majority are Hodgkin lymphomas, accounting for 50-70%, while non-Hodgkin lymphoma make up 15-25% [3].
Primary mediastinal lymphomas are most frequently of three histologic varieties:
Nodular sclerosing Hodgkin lymphoma
Primary mediastinal large B-cell lymphoma
Lymphoblastic lymphoma
Primary mediastinal large B-cell lymphoma is a sub-type of diffuse large B-cell lymphoma derived from the thymus [1, 3]. It represents less than 3 % of all non-Hodgkin lymphomas [2]. It is an aggressive neoplasm affecting a younger age group with female predilection. CT demonstrates a smooth, lobulated soft tissue attenuating bulky mass, with areas of necrosis. Other features include parenchymal invasion, pleural effusion, pericardial effusion, chest wall invasion, tracheal, oesophageal and vascular compression. However, it is difficult to differentiate primary mediastinal large B-cell lymphoma from Hodgkin lymphoma and lyphoblastic lymphoma on the basis of imaging findings alone [1]. Histopathology and immunohistochemistry are necessary to distinguish these entities [2].
In our case the age of the patient, clinical features, radiological appearance, laboratory findings and histopathology along with immunohistochemistry helped to establish the final diagnosis of an anterior mediastinal large B cell lymphoma.
Germ cell tumours are common in young adults and constitute 15% of all anterior mediastinal masses in adults. Histologically they are divided into benign teratomas, seminomas and embryonal tumours which are also known as malignant teratoma or non-seminomatous tumour [5].
75% of all mediastinal germ cell tumours are mature teratomas. Calcification, teeth, bone and/or fat in a lesion are indicative of a teratoma. Serum tumour markers, AFP, beta HCG are also helpful for the diagnosis of a germ cell tumour [4, 5]
Mediastinal lymphomas are common, either as part of a disseminated disease or less commonly as the site of primary origin. The mediastinum is commonly affected by systemic lymphomas. Only 10% of lymphomas which involve the mediastinum are primary and the majority are Hodgkin lymphomas, accounting for 50-70%, while non-Hodgkin lymphoma make up 15-25% [3].
Primary mediastinal lymphomas are most frequently of three histologic varieties:
Nodular sclerosing Hodgkin lymphoma
Primary mediastinal large B-cell lymphoma
Lymphoblastic lymphoma
Primary mediastinal large B-cell lymphoma is a sub-type of diffuse large B-cell lymphoma derived from the thymus [1, 3]. It represents less than 3 % of all non-Hodgkin lymphomas [2]. It is an aggressive neoplasm affecting a younger age group with female predilection. CT demonstrates a smooth, lobulated soft tissue attenuating bulky mass, with areas of necrosis. Other features include parenchymal invasion, pleural effusion, pericardial effusion, chest wall invasion, tracheal, oesophageal and vascular compression. However, it is difficult to differentiate primary mediastinal large B-cell lymphoma from Hodgkin lymphoma and lyphoblastic lymphoma on the basis of imaging findings alone [1]. Histopathology and immunohistochemistry are necessary to distinguish these entities [2].
In our case the age of the patient, clinical features, radiological appearance, laboratory findings and histopathology along with immunohistochemistry helped to establish the final diagnosis of an anterior mediastinal large B cell lymphoma.
Differential Diagnosis List
Primary mediastinal large B-cell lymphoma
Thymoma
Germ cell tumour teratoma
Mediastinal thyroid
Mediastinal tuberculosis
Final Diagnosis
Primary mediastinal large B-cell lymphoma
References
[1] K Shaffer, D Smith, D Kirn, W Kaplan, G Canellos, P Mauch and L N Shulman (1996) Primary mediastinal large-B-cell lymphoma: radiologic findings at presentation. AJR 167; 425-430 (PMID: 8686620)
[2] Johnson PW1, Davies AJ (2008) Primary mediastinal B-cell lymphoma. American society of hematology 2008.no 1;349-358
[3] Duwe BV1, Sterman DH, Musani AI (2005) Tumors of the mediastinum. chest 128(4):2893-2909 (PMID: 16236967)
[4] Brown LR1, Aughenbaugh GL (1991) Masses of the anterior mediastinum: CT and MR imaging. AJR Am J Roentgenol 157(6):1171-80. (PMID: 1950860)
[5] Kumar N, Gera C, Philip N. (2013) Isolated mediastinal tuberculosis: a rare entity. J Assoc Physicians India 61(3):202-3 (PMID: 24475683)
Case information
| URL: | https://eurorad.org/case/12895 |
| DOI: | 10.1594/EURORAD/CASE.12895 |
| ISSN: | 1563-4086 |
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Figure 2
Utrasound of the chest
Ultrasound of the left hemithorax shows minimal loculated pleural effusion.
Figure 3
Ultrasound of the chest
Ultrasound of the left hemithorax shows a heterogeneous intrathoracic mass.
Figure 4
Plain Chest CT, axial view
Plain chest axial CT shows a large left anterior mediastinal mass lesion without fat, without calcification, displacing the heart towards the right.
Plain chest coronal CT shows a large left anterior mediastinal mass lesion without fat, without calcification, displacing the heart towards the right.
Plain chest axial CT in the superior mediastinal region showing a large left anterior mediastinal mass displacing the trachea towards the right.
Figure 5
Chest CT, enhanced phase
Axial chest CT shows an enhancing left anterior mediastinal mass compressing the aortic arch.
Axial chest CT shows an enhancing left anterior mediastinal mass compressing the left pulmonary trunk and left main bronchus.
Axial chest CT, compressive atelectatic left lower lung with minimal left-sided pleural effusion. A left-sided thoracostomy tube is also seen in place.
Axial chest CT, showing a mass on the left with pericardial effusion.
Coronal chest CT shows an enlarged left anterior mediastinal mass with prominent left axilliary lymph nodes.
Chest AP
Plain chest radiograph shows complete opacifications of left lung, with contralateral shifting of mediastinal structure and trachea.
Department of Imiging, Manila Med, MCM Manila, Philippines
Department of Imiging, Manila Med, MCM Manila, Philippines
Utrasound of the chest
Ultrasound of the left hemithorax shows minimal loculated pleural effusion.
Division of Imaging, Manila Med, MCM, Manila, Philippines
Division of Imaging, Manila Med, MCM, Manila, Philippines
Ultrasound of the chest
Ultrasound of the left hemithorax shows a heterogeneous intrathoracic mass.
Department of imaging, Manila Med, MCM, Manila, Philippines
Department of imaging, Manila Med, MCM, Manila, Philippines
Plain Chest CT, axial view
Plain chest axial CT shows a large left anterior mediastinal mass lesion without fat, without calcification, displacing the heart towards the right.
Division of Imaging , Manila Med, MCM, Manila Philippines
Division of Imaging , Manila Med, MCM, Manila Philippines
Plain chest coronal CT shows a large left anterior mediastinal mass lesion without fat, without calcification, displacing the heart towards the right.
Division of Imaging , Manila Med, MCM, Manila Philippine
Division of Imaging , Manila Med, MCM, Manila Philippine
Plain chest axial CT in the superior mediastinal region showing a large left anterior mediastinal mass displacing the trachea towards the right.
Division of Imaging , Manila Med, MCM, Manila Philippin
Division of Imaging , Manila Med, MCM, Manila Philippin
Chest CT, enhanced phase
Axial chest CT shows an enhancing left anterior mediastinal mass compressing the aortic arch.
Division of Imaging , Manila Med, MCM, Manila, Philippines
Division of Imaging , Manila Med, MCM, Manila, Philippines
Axial chest CT shows an enhancing left anterior mediastinal mass compressing the left pulmonary trunk and left main bronchus.
Division of Imaging , Manila Med, MCM, Manila, Philippines
Division of Imaging , Manila Med, MCM, Manila, Philippines
Axial chest CT, compressive atelectatic left lower lung with minimal left-sided pleural effusion. A left-sided thoracostomy tube is also seen in place.
Division of Imaging , Manila Med, MCM, Manila, Philippines
Division of Imaging , Manila Med, MCM, Manila, Philippines
Axial chest CT, showing a mass on the left with pericardial effusion.
Division of Imaging , Manila Med, MCM, Manila, Philippines
Division of Imaging , Manila Med, MCM, Manila, Philippines
Coronal chest CT shows an enlarged left anterior mediastinal mass with prominent left axilliary lymph nodes.
Division of Imaging , Manila Med, MCM, Manila, Philippines
Division of Imaging , Manila Med, MCM, Manila, Philippines