Thymic and pulmonary mucosa-associated lymphoid tissue lymphomas in a patient with Sjögren’s syndrome and literature review

Thymus and lung mucosa-associated lymphoid tissue lymphoma with adenocarcinoma of the lung: a case report and literature review

BACKGROUND

Mucosa-associated lymphoid tissue (MALT) lymphoma is a common, low-grade, malignant B-cell lymphoma. However, simultaneous MALT lymphoma in the thymus and lung is extremely rare, and concomitant adenocarcinoma of the lung is even rarer. Herein, we report a rare case of a collision tumor in which MALT lymphoma was found in both the thymus and lung with Sjögren's syndrome (SS) and adenocarcinoma in the lung.

CASE PRESENTATION

A physical examination of a 32-year-old woman revealed an anterior superior mediastinal space-occupying lesion, and chest computed tomography (CT) indicated a nodular ground-glass opacity and irregular mixed-density focus in the right lung. All lung cancer-related tumor biomarkers were within normal ranges. The thymus and part of the lung tissue were surgically resected. The histopathology and molecular examinations confirmed MALT lymphoma of the thymus and lung with lung adenocarcinoma. SS was also diagnosed. No special postoperative treatment was performed for the MALT lymphoma, and the patient underwent immunosuppressive therapy for SS after 4 months of follow-up observation.

CONCLUSIONS

MALT lymphoma of the thymus and lung tissues has no specific presentation on imaging and is difficult to differentiate from common malignant tumors, and the definite diagnoses of these tumors are highly dependent on histopathological examination in combination with molecular testing and cytogenetics. SS may be an important potential condition for the occurrence of MALT lymphoma in the thymus and lung. Additional similar cases are needed to clarify the biological pathways and potential molecular mechanisms of rare lymphomas and collision tumors.

Mucosa-associated lymphoid tissue lymphoma in thymus: a SEER analysis

OBJECTIVES

The present study explores an extremely rare disease, thymic mucosa-associated lymphoid tissue (MALT) lymphoma, for its characteristics and prognostic factors by analyzing the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

From 2000 to 2018, cases with a diagnosed thymic MALT lymphoma were extracted. Clinical characteristics, treatments, and survival patterns of these cases were analyzed.

RESULTS

Thymic MALT lymphoma (n = 26) accounted for 0.09% of all MALT lymphomas. With a sex ratio of 0.53 (male/female), 68% white population was affected. Most cases were diagnosed with Ann Arbor stage I (50%), yet advanced-stage did not show worse prognosis (p = 0.236). Different treatment protocols did not influence the overall prognosis (p > 0.99). The 5- and 10- year overall survival rates were 83.1% and 78.2%, respectively. Older than 70 years may be an independent risk factor for overall survival (HR = 7.166 [95% CI 1.173-43.756], p = 0.033).

CONCLUSION

Thymic MALT lymphoma is a highly rare disease with a favorable prognosis. Ann Arbor staging might not be appropriate to classify severity of this disease or its treatment. Older people may have worse survival. A standardized treatment mode needs to be established, and surgery could remain as the mainstay.

Characterization of molecular genetics and clinicopathology in thymic MALT lymphoma

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a type of low-grade malignant B-cell lymphoma. The aim of this study was to investigate the clinicopathological characteristics of thymic MALT lymphoma. We analyzed the clinical, morphological, immunophenotypical, cytogenetic, and molecular characteristics of 11 cases of thymic MALT lymphoma. The relevant literature was also reviewed. The median age of the 11 patients was 50 (range: 33-60). There was a female predominance with a female-to-male ratio of 10:1. Three patients presented with Sjögren syndrome, autoimmune thrombocytopenia purpura, and type B1 thymoma, respectively. Microscopically, thymic MALT lymphoma was characterized by epithelium-lined cysts that were surrounded by small lymphocytes, centrocyte-like cells, and monocytoid B-cells. Plasmacytic differentiation was observed in two cases. The tumor cells expressed CD20, CD79α, and BCL2. Clonal immunoglobulin genes were detected in all 8 examined cases. Fluorescence in situ hybridization (FISH) for 18q21 was performed in 7 cases, and no translocations involving 18q21 were found. Targeted gene sequencing was performed in five cases with available DNA samples, and TNFAIP3, CARD11, IGLL5, and CCND3 mutations were identified. Thymic MALT lymphoma is a rare type of B cell malignancy with a female predominance and excellent clinical outcomes. Molecular aberrations involving the NF-κB pathway are frequent in thymic MALT lymphoma, suggesting that dysregulation of the NF-κB pathway is an important mechanism underlying the pathogenesis of thymic MALT lymphoma.

Pulmonary Involvement in Sjögren Syndrome

Sjögren syndrome (SS) is a progressive autoimmune disease characterized by dryness, predominantly of the eyes and mouth, caused by chronic lymphocytic infiltration of the lacrimal and salivary glands. Extraglandular inflammation can lead to systemic manifestations, many of which involve the lungs. Studies in which lung involvement is defined as requiring the presence of respiratory symptoms and either radiograph or pulmonary function test abnormalities quote prevalence estimates of 9% to 22%. The most common lung diseases that occur in relation to SS are airways disease and interstitial lung disease. Evidence-based guidelines to inform treatment recommendations for lung involvement are largely lacking.

Imaging manifestations of autoimmune disease-associated lymphoproliferative disorders of the lung

Lymphoproliferative disorders (LPDs) may involve intrathoracic organs in patients with autoimmune disease, but little is known about the radiologic manifestations of autoimmune disease-associated LPDs (ALPDs) of the lungs. The purpose of our work was to identify the radiologic characteristics of pulmonary involvement in ALPDs. A comprehensive search for PubMed database was conducted with the combination of MeSH words. All articles which had original images or description on radiologic findings were included in this analysis. Also, CT images of eight patients with biopsy-proven lymphoproliferative disorder observed from our institution were added. Overall, 44 cases of ALPD were identified, and consisted of 24 cases of bronchus-associated lymphoid tissue lymphoma (BALToma), eight cases of non-Hodgkin's lymphoma (NHL), six cases of lymphoid interstitial pneumonia (LIP), two cases of nodular lymphoid hyperplasia, two cases of unclassified lymphoproliferative disorder, and one case each of lymphomatoid granulomatosis and hyperblastic BALT. Multiple nodules (n = 14, 32 %) and single mass (n = 8, 18 %) were the predominant radiologic manifestations. The imaging findings conformed to previously described findings of BALToma, NHL, or LIP. Data suggest that BALToma, NHL, and LIP are the predominant ALPDs of the lung, and ALPD generally shared common radiologic features with sporadic LPDs. Familiarity with ALPDs and their imaging findings may enable radiologists or clinicians to include the disease as a potential differential diagnosis and thus, to prompt early biopsy followed by appropriate treatment.

An 11-year and 10-month-old girl with purpura and chest pain

Mucosa-associated lymphoid tissue lymphoma (MALToma) is a type of B-cell lymphoma. Case reports of childhood thymic MALToma and its association with vasculitis are rarely found in the related literature. Herein, we present a report of an 11-year and 10-month-old girl who was initially diagnosed with cutaneous vasculitis characterized by nonthrombocytopenic palpable purpura, positive antinuclear antibody and anti-SSA (Ro) antibody. Eight months later, a thymic mediastinal mass was found. Surgical excision was performed and results of pathological analysis revealed an extranodal marginal zone CD20(+) B-cell MALToma. Benign response to the chemotherapeutic regimen of Berlin-Frankfurt-Münster group NHL-BFM 90 R2 without relapse was noted in 2 years of follow-up. For the first time, our case demonstrated some clinical evidence of the association between vasculitis and childhood MALToma.

Primary MALT-type lymphoma of the thymus: a clinicopathological and immunohistochemical study of six cases

BACKGROUND

Six cases of primary extranodal marginal zone B-cell lymphoma of the thymus (MALT [mucosa-associated lymphoid tissue]) are described.

METHODS

The patients were all women between 48 and 59 years. Clinically, all patients, except for one, were Caucasians. Two patients had a history of autoimmune disease, while one was being investigated for such a possibility. The remaining three patients did not have a history of autoimmune disorders.

RESULTS

In those patients who had symptoms related to their anterior mediastinal masses, nonspecific symptoms, including shortness of breath and chest pain, predominated. Histologically, the tumors had the classical morphologic features of cystic and solid areas with an atypical monocytoid cellular proliferation. Immunohistochemical stains performed in all cases showed kappa monotypic expression and B-cell phenotype.

CONCLUSIONS

The current cases highlight that MALT lymphomas of the thymus can occur in a setting not related to autoimmune disease or in those not of Oriental ethnic background and that mediastinal cystic lesions require proper sampling in order to adequately evaluate the possibility of MALT lymphoma.

Thymic extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue: a clinicopathological and genetic analysis of six cases

We investigated six new cases of primary thymic extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) to further characterize the clinicopathological and genetic features. The male to female ratio was 1:1. One female patient had suffered from systemic lupus erythematosus. Another female patient was diagnosed with rheumatoid arthritis after thymectomy. One patient had a concurrent tumor in the eyelid. Radiologically, all tumors were located in the prevascular space and presented as asymmetric heterogeneously enhanced cystic and solid masses. MALT1, BCL10 or IGH translocations and trisomy 18 were not observed in any cases by fluorescence in situ hybridization (FISH) analysis. Trisomy 3 was detected in one patient and another showed a TNFAIP3/A20 deletion. Meta-analysis (n = 51) including the present and previously reported cases revealed that the prevalence of autoimmunity was much lower in males with thymic MALT lymphoma compared to females (33% vs. 87%, p = 0.001). Additionally, the average age of females or patients with autoimmunity was about 10 years younger than that of males or patients without autoimmunity (p = 0.003 and p = 0.008, respectively). In summary, thymic MALT lymphoma arising without underlying autoimmunity frequently involves males or older patients. Trisomy 3 and an A20 deletion might play a role in the pathogenesis of thymic MALT lymphoma.

Pulmonary involvement in Sjögren syndrome

Sjögren syndrome is a slowly progressing autoimmune disease. Pulmonary manifestations are frequent in primary Sjögren syndrome but often not clinically significant; the most common are xerotrachea, interstitial lung diseases, and small airway obstruction. Pulmonary manifestations in Sjögren syndrome have a slow progression and favorable prognosis, with the exception of primary pulmonary lymphoma and pulmonary hypertension.

[Association between thymic MALT lymphoma and Sjögren's syndrome]

INTRODUCTION

Thymic mucosa-associated lymphoid tissue (MALT) lymphoma is a rare pathology, often associated with autoimmune diseases. The authors report the case of an Asian woman with Sjögren's syndrome.

OBSERVATION

A 48-year-old Chinese woman, without past medical history and a non-smoker, presented an alteration in her overall condition, dyspnoea at exercise, inflammatory polyarthralgia, and a dry eye and mouth syndrome over the last few months. Thoracic tomodensitometry detected an anterior heterogenic cystic mediastinal mass. A mediastinotomy was performed. The diagnosis of the surgical biopsy was thymic MALT lymphoma. The authors also diagnosed Sjögren's syndrome with the presence of four diagnostic criteria. Chemotherapy by rituximab, cyclophosphamide, vincristine, prednisone induced major tumoral regression. The patient declined surgery and will be monitored.

CONCLUSION

Thymic MALT lymphoma is a rare pathology. There is a high correlation with autoimmune diseases, like Sjögren's syndrome. Its appearance is that of an anterior mediastinal mass with a cystic component. The treatment is not well codified and is most often based on surgical resection, eventually followed by chemotherapy or radiotherapy. As far as the authors know, this is the second case of thymic MALT lymphoma treated by exclusive chemotherapy.

Mucosa associated lymphoid tissue (MALT) lymphoma of the thymus with trisomy 18

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) of the thymus is rare and little is known about its karyotype abnormality. MALT lymphoma in general shows a good prognosis, but some reports suggest that the presence of trisomy 18 predicts recurrence. Here, we report a patient with MALT lymphoma of the thymus and the left parotid gland accompanied by Sjogren's syndrome. The karyotype analysis revealed that this is the first case of thymic MALT lymphoma with trisomy 18, which we believe is worth reporting. We also review cases with thymic MALT lymphoma previously reported in the literature.