Pulmonary extranodal marginal zone B-cell lymphoma of mucosa-associated lymph tissue: A case report and literature review

Pulmonary mucosa-associated lymphoid tissue lymphoma with Sjögren's syndrome and literature review: A case report

INTRODUCTION

A 54-year-old woman was admitted to hospital with chest tightness, shortness of breath, and chest pain on exertion. Her chest computed tomography showed a space-occupying lesion in the right lower lobe of the lung.

CASE PRESENTATION

The ultrasound-guided right lung mass biopsy showed mucosa-associated lymphoid tissue (MALT), and the patient was diagnosed with Sjögren's syndrome (SS). The patient's symptoms were partially relieved with chemotherapy.

CONCLUSIONS

Autoimmune diseases like SS and systemic lupus erythematosus are recognized risk factors for pulmonary MALT. It is necessary to identify predictors of malignant transformation of SS to pulmonary MALT lymphoma.

Role of 18F-FDG PET/CT in patients affected by pulmonary primary lymphoma

Background

Primary pulmonary lymphoma (PPL) is defined as clonal abnormal hyperplasia of lung parenchyma or bronchial lymphoid tissue originating from bronchial mucosal tissue. However, PPL is rare, which accounts for approximately 3-4% of extraneurotic lymphomas and 0.5-1% of all primary tumors in the lung. Owing to the lack of any typical clinical symptoms and radiological features, it is challenging to accurately diagnose PPL, which affects its clinical management and prognosis. Considering this, herein, we aim to raise awareness of this disease and help physicians understand the role of 18F-FDG PET/CT in the diagnosis of PPL.

Method

A retrospective analysis was performed on the clinical and 18F-FDG PET/CT imaging data of 19 patients diagnosed with PPL by biopsy pathology at our hospital from April 2014 to December 2021.

Results

Of the 19 PPL patients, 15 patients showed clinical symptoms with the most common being fever and cough. In addition, there were 4 cases that had no clinical symptoms, and all of them were MALT lymphoma. In fact, 16 patients were misdiagnosed as lobar pneumonia, lung cancer, tuberculosis, and diffuse interstitial inflammation, representing a misdiagnosis rate of 84.2%. Also, 73.7% were MALT lymphomas, representing the most common pathological pattern, along with 3 DLBCL and 2 T-cell lymphomas. With reguard to CT signs, the air-bronchial sign was found to be the most common, followed by the halo sign and the collapsed leaf sign. On the basis of the predominant radiologic features, lesions were categorized as pneumonic consolidation, nodular/mass type, diffuse interstitial type, and mixed type. The average SUVmax of lesions was 7.23 ± 4.75, the ratio of SUVmax (lesion/liver) was 3.46 ± 2.25, and the ratio of SUVmax (lesion/mediastinal blood pool) was found to be 5.25 ± 3.27. Of interest, the different pathological types of PPL showed different values of 18F-FDG uptake. The 18F-FDG uptake of DLCBL was the most prominent with a SUVmax of 15.33 ± 6.30 and was higher than that of MALT lymphoma with a SUVmax of 5.74 ± 2.65. There appeared similarity in 18F-FDG uptake between MALT lymphoma and T-cell lymphoma. For the SUVmax of lesion, we found statistical significance between MALT lymphoma and DLCBL (P value<0.001). In addition, we also found statistical significance (P value < 0.05) in SUVmax of lesions between pneumonic consolidation type and nodal/mass type, I stage, and other stages.

Conclusions

On 18F-FDG PET/CT images, certain features of PPL morphology and metabolism can be identified that may contribute to a better understanding of this disease. In addition, 18F-FDG PET/CT whole-body imaging has the potential to refine the staging of PPL. Most importantly, functional 18F-FDG PET/CT imaging can readily reflect tumor cell activity, thus allowing for the selection of an optimal biopsy site.

Primary Pulmonary MALT Lymphoma: A Case Report and Literature Review

Background

Primary pulmonary MALT (mucosa-associated lymphoid tissue) lymphoma is a rare entity that imposes a rigorous and demanding diagnostic work-up.

Case Report

We present the case of a 74-year-old female non-smoker with a previous healed pulmonary tuberculosis and a history of arterial hypertension and fibromyalgia. She was referred to the pulmonology clinic to investigate a right inferior lobe (RIL) rounded pulmonary opacity (4 × 3.4 cm) identified on a previous thoracic CT scan performed for unrelated reasons. The remaining findings were non-specific and included small calcified mediastinal and hepatic adenopathies and multiple calcified hepatosplenic foci. The ¹⁸F-FDG-PET revealed high ¹⁸F-FDG uptake at the RIL lesion (SUV 4.7), suspicious for neoplastic involvement. Flexible bronchoscopy and CT-guided transthoracic needle biopsy were non-diagnostic and she was submitted to videothoracoscopy with surgical biopsy. The histological and immunohistochemical examination of the clear margin RIL segmentectomy were in keeping with a MALT lymphoma.

Conclusion

The authors present this case to highlight this rare entity, which is particularly challenging to diagnose due to non-specific multimodality imaging features, frequently implying more invasive procedures and surgical biopsy for a final diagnosis.

Retrospective Analysis of 9 Cases of Primary Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma and Literature Review

Background

Primary pulmonary mucosa-associated lymphoma tissue lymphoma is rare and is often misdiagnosed because of its diverse and nonspecific clinical features. The aim of this study was to raise awareness among clinicians and to share our experience of treating and managing such patients.

Material/Methods

This retrospective study was conducted between 1 January 2009 and 31 October 2017 at the First Affiliated Hospital of Guangxi Medical University. All cases were confirmed via pathology and immunohistochemistry. In addition, we reviewed all relevant literature.

Results

Altogether, 21 patients (7 female, 14 male) with a median age of 54 (range, 19–84) years were diagnosed with primary pulmonary mucosa-associated lymphoma. Expiratory dyspnea, repeated cough and expectoration, and weight loss were the most common symptoms. Pulmonary lesions were found via physical examination in 10 patients who had no obvious symptoms. Chest computed tomography showed nodules, pulmonary consolidation, bronchial bronchogram, ground-glass opacity, and mediastinal lymph node enlargement. Some patients were misdiagnosed with tuberculosis and pneumonia, while others were initially diagnosed with cancer. Tumor pathology and immunocytochemistry indicated primary pulmonary mucosa-associated lymphoma tissue lymphoma. Six patients underwent chemotherapy, 5 underwent surgery, 4 underwent surgery and chemotherapy, 3 were only observed, and 3 refused treatment.

Conclusions

The development of primary pulmonary mucosa-associated lymphoid tissue lymphoma is slow and insidious. Having no specific clinical symptoms and imaging findings, it is easily misdiagnosed. Final diagnosis is made via pathologic evaluation and immunohistochemistry. Surgery and chemotherapy are the primary treatment modalities and yield a good prognosis.