Marginal zone B-cell non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue type: imaging findings

Pulmonary mucosa-associated lymphoid tissue lymphoma: insights from a 15-year study at a single institution involving 14 clinical cases

OBJECTIVE

This study aims to delineate the clinical presentations, imaging features, pathological characteristics, therapeutic strategies, and outcomes of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma, thereby deducing the most efficacious treatment paradigm.

METHODS

We conducted a retrospective review of 14 patients diagnosed with pulmonary MALT lymphoma at the Second Xiangya Hospital, affiliated with Central South University, between September 2007 and September 2022, focusing on their clinical profiles, diagnostic pathways, treatment modalities, and prognostic outcomes.

RESULTS

The cohort's median age was 60 years (ranging from 44 to 81 years), with 64.29% being female and only 14.29% having a history of smoking. The incidence of immunodeficiency diseases among the patients was notably low. Imaging typically revealed pulmonary nodules and masses, with air bronchogram signs evident in 9 patients and pleural effusion in 2. CD20 expression was markedly positive across the board in all patients with pulmonary MALT lymphoma. Among the 12 patients who received intervention, 6 were treated with chemotherapy alone, 2 underwent surgical resection, and 4 benefitted from a combined approach of chemotherapy and surgery. Over the monitoring period, 2 patients succumbed to their disease. The estimated 5- and 10-year overall survival (OS) rates were 91.67% and 76.39%, respectively, with the median progression-free survival (PFS) reaching 7 years. Comparative analysis revealed no significant disparity in PFS between patients treated exclusively with chemotherapy and those receiving both chemotherapy and surgical intervention (P = 0.22).

CONCLUSION

Pulmonary MALT lymphoma typically exhibits a slow course, with gradual progression and a predominantly positive prognosis. Chemotherapy emerges as the preferred therapeutic option for managing this malignancy.

A CT-based radiomics nomogram for differentiation of lympho-associated benign and malignant lesions of the parotid gland

OBJECTIVES

Preoperative differentiation between benign lymphoepithelial lesion (BLEL) and mucosa-associated lymphoid tissue lymphoma (MALToma) in the parotid gland is important for treatment decisions. The purpose of this study was to develop and validate a CT-based radiomics nomogram combining radiomics signature and clinical factors for the preoperative differentiation of BLEL from MALToma in the parotid gland.

METHODS

A total of 101 patients with BLEL (n = 46) or MALToma (n = 55) were divided into a training set (n = 70) and validation set (n = 31). Radiomics features were extracted from non-contrast CT images, a radiomics signature was constructed, and a radiomics score (Rad-score) was calculated. Demographics and CT findings were assessed to build a clinical factor model. A radiomics nomogram combining the Rad-score and independent clinical factors was constructed using multivariate logistic regression analysis. The performance levels of the nomogram, radiomics signature, and clinical model were evaluated and validated on the training and validation datasets, and then compared among the three models.

RESULTS

Seven features were used to build the radiomics signature. The radiomics nomogram incorporating the clinical factors and radiomics signature showed favorable predictive value for differentiating parotid BLEL from MALToma, with AUCs of 0.983 and 0.950 for the training set and validation set, respectively. Decision curve analysis showed that the nomogram outperformed the clinical factor model in terms of clinical usefulness.

CONCLUSIONS

The CT-based radiomics nomogram incorporating the Rad-score and clinical factors showed favorable predictive efficacy for differentiating BLEL from MALToma in the parotid gland, and may help in the clinical decision-making process.

KEY POINTS

• Differential diagnosis between BLEL and MALToma in parotid gland is rather difficult by conventional imaging modalities. • A radiomics nomogram integrated with the radiomics signature, demographics, and CT findings facilitates differentiation of BLEL from MALToma with improved diagnostic efficacy.

Role of F-18 FDG PET/CT in non-conjunctival origin ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphomas

Background

Despite the widespread use of F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in the diagnosis and response assessment of patients with lymphoma, few studies have assessed its value in ocular adnexal lymphomas. The purpose of this study was to evaluate the role of FDG PET/CT in staging of non-conjunctival origin ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphomas (OAML). In addition, the diagnostic sensitivity of FDG PET/CT was compared with magnetic resonance imaging (MRI). FDG PET/CT of 123 consecutive patients with pathologically proven OAML between January 2009 and February 2016 were retrospectively reviewed. The patients with MALT lymphoma originating from conjunctiva were excluded. A total 50 patients with non-conjunctival origin OAML were assessed. Maximum standardized uptake value (SUVmax) and additional PET parameters were measured for all lesions. Sensitivity for primary tumor detection was compared with MRI.

Results

Ten patients had bilateral OAML and total 60 OAML lesions were analyzed. MRI was missing in one patient. The tumor locations were as follows: eyelid, 9; lacrimal gland, 18; orbit, 33. Fifty lesions (83.3%) were FDG-avid tumors with mean ± SD SUVmax 4.8 ± 2.4 (range 2.0~11.1). The mean SUVmax according to tumor location were as follows: eyelid, 3.7 ± 1.1 (2.8~5.3); lacrimal gland, 3.6 ± 1.4 (2.1~6.4); orbit, 5.7 ± 2.6 (2.0~11.1). Mean SUVmax among the 3 locations were statistically different (P = 0.010). The sensitivity was calculated as 83.1% (49/59) for FDG PET/CT and 89.8% (53/59) for MRI, which were statistically comparable (P = 0.219 by McNemar’s test). Seven of 50 patients (14%) were upstaged by detection of extraocular lesions by FDG PET/CT (1 kidney and lung, 1 tonsil, 4 cervical LNs, 1 sacral foramen).

Conclusion

83.3% of the non-conjunctival origin OAML were FDG-avid tumors, with FDG PET/CT showing comparable sensitivity to that of MRI. FDG PET/CT detected unsuspected extraocular lymphoma involvement in 14% of the patients. FDG PET/CT performed for staging of non-conjunctival origin OAML may thus guide therapeutic management.

Multimodality imaging of indolent B cell lymphoma from diagnosis to transformation: what every radiologist should know

Indolent B cell lymphomas are a group of lymphoid malignancies characterized by their potential to undergo histologic transformation to aggressive lymphomas. While different subtypes of indolent B cell lymphomas demonstrate specific clinical and imaging features, histologic transformation can be suspected on cross-sectional imaging when disproportionate lymph node enlargement or new focal lesions in extranodal organs are seen. On PET/CT, transformed indolent lymphoma may show new or increased nodal FDG avidity or new FDG-avid lesions in different organs. In this article, we will (1) review the imaging features of different subtypes of indolent B cell lymphomas, (2) discuss the imaging features of histologic transformation, and (3) propose a diagnostic algorithm for transformed indolent lymphoma. The purpose of this review is to familiarize radiologists with the spectrum of clinical and imaging features of indolent B cell lymphomas and to define the role of imaging in raising concern for transformation and in guiding biopsy for confirmation.

Non-Hodgkin lymphoma involving the parotid gland: CT and MR imaging findings

OBJECTIVES

As an uncommon neoplasm, parotid non-Hodgkin lymphoma (NHL) comprises mucosa-associated lymphoid tissue (MALT) and non-MALT lymphomas. Both types of lymphoma vary in prognosis and treatment. The aim of this study was to explore CT and MRI characteristics of these two types of lymphoma.

METHODS

61 cases of parotid NHL, 34 MALT and 27 non-MALT lymphomas with histopathological confirmation were examined with routine CT and MR scans prior to treatment, and retrospectively reviewed.

RESULTS

On CT and MRI, 34 MALT lymphomas presented with 11 solid and 23 solid-cystic forms, whereas 27 non-MALT lymphomas presented with 25 solid and 2 solid-cystic forms (p < 0.01).

CONCLUSIONS

Parotid MALT lymphoma is characterized mainly by the solid-cystic form, whereas non-MALT lymphoma is characterized mainly by the solid form. The differences on CT and MRI can offer helpful information for differentiation of both types of parotid NHL.

Slow-growing primary marginal zone B-cell lymphoma arising in the chest wall in a patient without a history of tuberculosis

A 57-year-old man with a 15-year history of a right chest wall mass lesion without follow-up for 5 years was admitted to our hospital without any symptoms or evidence of malignancy. On MRI, an additional small subcutaneous mass lesion was found. Histology of both lesions revealed marginal zone B-cell lymphomas. Primary chest wall marginal zone B-cell lymphomas are rare; this report discusses the case and the literature on chest wall lymphomas.

[clinicopathological analysis of pulmonary marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue]

BACKGROUND AND OBJECTIVE

As a rare disease, pulmonary marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (PMZL-MALT), is often misdiagnosed. The aim of this study is to summarize the clinical and pathological features of this disease and improve the awareness of doctors.

METHODS

Seven cases (female 5, male 2) diagnosed of PMZL-MALT in West China Hospital between November 2008 and November 2010, were analyzed retrospectively, including their symptoms, radiological findings, pathological examinations, treatment and prognosis.

RESULTS

The median age of the patients were 62 years old (range 34-79 years). Six patients suffered from cough and sputum. Pulmonary consolidation was the most frequent manifestation, leading a misdiagnosis of pneumonia with CT examinations. Pathological diagnosis was obtained via fiberoptic bronchoscopy in six patients and percutaneous pulmonary biopsy for the rest one. In the seven cases, immunohistochemical results showed CD20(+), CD79a(+), while CD3 epsilon(-), CD5(-), CyclinD1(-), CD10(-), Bcl-2(-) and CD30(-). Additionally, the expression of Ki-67 was below 10%. Further PCR analysis showed evidence of immunoglobulin heavy chain gene rearrangement in tissues from six subjects. Based on the disease location and patients' wishes, compared with two cases just receiving symptomatic treatments, the other five ones took in chemotherapies.

CONCLUSION

Since there were no specific clinical features for patients of PMZL-MALT, histopathological examination was the only effective means to confirm the diagnosis.