Primary Pulmonary Diffuse Large B Cell Lymphoma Mimicking Metastasis: A Case Report and Literature Review

Primary pulmonary lymphoma in Peru

Objective

To describe the clinical features, imaging, pathology and management of patients with primary pulmonary lymphoma (PPL).

Methodology

This is a case series study involving a retrospective analysis of 24 patients diagnosed with PPL between the years 2000-2019 at Instituto Nacional de Enfermedades Neoplásicas in Lima, Perú.

Results

73.9% of patients were male. Cough (78.3%) and weight loss (56.5%) were the most frequent clinical features. Dyspnoea and elevated values of DHL and B2 microglobulin were frequently altered in advanced stages. Diffuse large B cell lymphoma (DLBCL) represented 47.8% of the cases and the most common radiologic alterations were a mass (60%) and consolidation with air bronchogram (60%). The most utilised treatment was chemotherapy alone (60%). Three patients received only surgery. Median survival was 30 months. Five overall survival was 45%, and up to 60% in the case of mucosa-associated lymphoid tissue lymphoma.

Conclusion

PPL is infrequent. Clinical features are unspecific and the principal finding is a mass, nodule or consolidation with air bronchogram. Definitive diagnosis needs biopsy and immunohistochemistry. There is no standard treatment, it depends on histology type and stage.

Primary pulmonary diffuse large B-cell lymphoma presenting multiple nodules mimicking metastasis: A case report

Primary pulmonary diffuse large B-cell lymphoma is a rare entity. We describe a case of pulmonary lymphoma with multiple nodules mimicking metastases in a treated patient with rheumatoid arthritis. A 73-year-old man was diagnosed with rheumatoid arthritis at the age of 30. He was treated with leflunomide. He was followed up for a nontuberculous mycobacterial infection. He underwent percutaneous coronary intervention for acute myocardial infarction at the age of 70. In April 2022, routine follow-up revealed new-onset multiple nodules on chest computed tomography (CT). A position emission tomography/CT scan with 18F-fluorodeoxyglucose showed a low-high maximum standardized uptake value by multiple nodules. Pathologic examination of a video-assisted thoracic surgical biopsy revealed pulmonary diffuse large B-cell lymphoma. Systemic chemotherapy with rituximab, cyclophosphamide, vincristine, and prednisolone reduced and eliminated multiple nodules. Pulmonary lymphoma should be considered as a differential diagnosis in the case of multiple nodules on a chest CT.

LAG3 and PD1 Regulate CD8+ T Cell in Diffuse Large B-cell Lymphoma Patients

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a clinically and genetically heterogeneous lymphoid malignancy. The unsatisfactory outcome for refractory patients has prompted efforts to explore new therapeutic approaches for DLBCL. However, the mechanisms involved in treatment associated with immune checkpoints remain unclear. This study is aimed at investigating the potential roles of programmed cell death protein 1 (PD1) and lymphocyte activation gene 3 (LAG3) in CD8+ T cells for treatment in DLBCL.

METHODS

Utilizing flow cytometry, we examined the content of T cells, the levels of cytokines, and the expression of PD1 and LAG3 in patients with DLBCL as well as in healthy controls. Levels of cytokines in CD8+ T cells from DLBCL patients before and after treatment were compared by blocking of PD1 and LAG3 in magnetic bead-sorted CD8+ T cells.

RESULTS

We found that the proportion of CD4+ T cells and CD8+ T cells was increased in DLBCL patients after treatment. The levels of cytokines trended toward those of healthy controls in treatment. PD1 (+), LAG3 (+), or PD1 (+) LAG3 (+) were all expressed in lower amounts in CD4+ T cells and CD8+ T cells after treatment than in untreated DLBCL patients. In addition, blockade of PD1 and LAG3 in sorted CD8+ T cells markedly inhibited cytokine production in response to treatment.

CONCLUSION

PD1 and LAG3 in CD8+ T cells may be important targets of therapy and play therapeutic role in patients with DLBCL.