NHL of the pleural cavity

Clinical History

74-years old male showing severe chest pain and dyspnoe, weight loss and low grade fever over the last month.

Imaging Findings

A 74-year-old male underwent therapeutic pneumothorax for right pulmonary tuberculosis 43 years ago. Few month ago the patient developed severe chest pain and dyspnoe, weight loss and low grade fever. The patient had quit smoking more than 25 years ago. Conventional X-ray showed a large mass in the right apex. The shape of the pleural interface was indeterminate in a.p. projection due to the overlaying pacemaker device. However, side projection showed clearly the pleural origin of the mass. Computed tomography revealed a large tumor in the posterior aspect of the right upper hemithorax measuring 9 x 6.5 x 7 cm. The tumor showed an extensive pleural involvement. Several coarse calcifications were seen, mostly lining the visceral pleura but also located more centrally in the tumor. Both dorsal upper as well as apical lower lobe of the right lung were affected. The fourth dorsal rib showed a periostal reaction without osteolysis which was interpreted as a sign of beginning chest wall invasion. No lymph node enlagement was seen.

Discussion

The patient had quit smoking more than 25 years ago, however, he was clinically diagnosed of peripheral lung cancer and scheduled for surgery. Diagnosis of a malignant process was made on surgical examination, where the whitish soft lesion presented with invasion of the parietal and visceral pleura. The Tumor was completely resected by upper right lobectomy. The tumor cells were positive for CD45, CD43, CD30 and EBV (EBER), but negative for B, T and NK markers(Figure 3). MIB-1 proliferation fraction was 50% (Figure 3). Sothern blot analysis of the IgH gene showed B-cell clonality and confirmed the diagnosis of pyothorax associated B-cell lymphoma. This type of lymphoma occurs in patients with normal immune system and is characterized by the presence of EBV infection. An EBV-mediated growth promotion together with genetic lesions (including p53 gene) and contribution of inflammatory cytokines are described as possible factors causing malignant transformation (1). A review of literature showed that malignant lymphomas arising in the lung or pleura constituted only about 0.3% of all non-Hodgkin’s lymphoma. A wide range of radiologic presentations of NHL of the lung has been described including ground glass pattern, reticulo-nodular pattern, pulmonary nodules with and without cavitation, pulmonary masses and widespread alveolar consolidations. Primary NHL of the lung can be divided into : 1. BALT lymphomas (B-cell), 2. malignant neoplastic endotheliosis (B-cell), 3. lymphomatoid granulomatosis (T-cell), 4. angioimmunoblastic lymphadenopathy (T-cell). Subpleural lymphomatoid tissue, located just beneath the visceral pleura, is a common presentation of NHL. Shuman et al found pleural and subpleural manifestations of lymphoma in 31% of patients with advanced or recurrent lymphoma (2). CT showed either subpleural nodules or pleural plaques. However, no histopathologic correlation was performed to clearly distinguish the pleural from supleural (pulmonary) form of disease. Pleural and subpleural lymphoma presented as solid lesions without calcifications and cystic changes at initial presentation. Calcifications and areas of necrosis may occur as a result of treatment. However, all this findings were made in patients with advanced disease and involvement of the pleura and subpleural lung was secondary to pulmonary lymphoma or lymphoma of the ribs. There was no case of primary pleural lymphoma in this large series. Primary NHL of the pleural cavity is very rare and has been described in association with a long-standing chronic tuberculous pyothorax. The cases were reported almost exclusively from Japan (3). Case-control studies however suggest that artificial pneumothorax for the treatment of pulmonary tuberculosis or tuberculous pleuritis leading to chronic non-healing inflammation in the pleural cavity may result in a significant increased risk for the development of pleural lymphoma (1, 4). Without these predisposing factors primary pleural lymphoma without other organ involvement is extremely rare. Additional pleural involvement in patients with NHL of the lung is much more common (2). Furthermore, cases of Aids-related primary lymphoma of the pleural cavity have been described(5). Our patient did not reveal any other manifestations of his lymphoma. Bone marrow was not infiltrated.

Differential Diagnosis List

Final Diagnosis

Non - Hodgkin lymphoma of the pleural cavity

URL:	https://www.eurorad.org/case/724
DOI:	10.1594/EURORAD/CASE.724
ISSN:	1563-4086