Pulmonary marginal zone lymphoma: a single centre experience and review of the SEER database

The prognosis of patients with primary pulmonary mucosa-associated lymphoid tissue lymphoma: Treated with surgery or chemotherapy?

OBJECTIVES

The goal of this project was to evaluate the effect of surgical treatment and the long-term survival of patients with staged IE/IIE pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma.

METHODS

From January 2004 to December 2018, we retrospectively analysed 96 patients diagnosed with low-stage primary pulmonary MALT lymphoma according to the modified Ann Arbor staging system (IE/IIE). We compared the outcomes of different treatment modalities for staged IE/IIE MALT lymphoma. Progression-free survival (PFS) and overall survival were estimated using Kaplan-Meier curves, and the differences were compared using the log-rank test. The Cox proportional hazards model was used in this study.

RESULTS

The median PFS time of low-staged MALT lymphomas was 118 months. The overall survival and PFS of the radical surgery group and the biopsy + chemotherapy group suggested no significant difference (P = 0.63, P = 0.65). Patients positive for Blc-2 and Ki-67 suffered from a compromised PFS (P = 0.023, P = 0.006). The Cox adjusted proportional hazards model analysis suggested that surgical procedures were not protective factors for patients with low-staged (IE/IIE) pulmonary MALT lymphoma, whereas being positive for Blc-2 and Ki-67 was a risk factor for patients with low-staged pulmonary MALT lymphoma (hazard ratio: 9.567; P = 0.044; hazard ratio: 6.042, P = 0.049).

CONCLUSIONS

Our findings suggested that for staged IE/IIE pulmonary MALT lymphoma, radical surgical resection did not provide a survival benefit compared with chemotherapy after biopsy. Thus, radical surgery may be avoided unless biopsy is necessary for a diagnosis that requires sublobar resection. For those lesions that were Blc-2- or Ki-67-positive, compromised survival may be suggested.

Very low-dose radiotherapy for extranodal marginal zone lymphoma of bronchus-associated lymphoid tissue

Extranodal marginal zone lymphoma of bronchus-associated lymphoid tissue (BALT) is a rare cancer for which optimal treatment strategies are undefined. Retrospective analyses suggest excellent outcomes with surgical resection for localized BALT lymphoma; however, the role of radiotherapy remains underexplored. We report the largest-to-date single-center analysis of 13 primary BALT lymphoma patients treated with radiotherapy. Of 15 treated lesions, we report a 100% response rate with complete response (CR) achieved in 67% of lesions. Among 10 lesions treated with very low-dose radiotherapy (VLDRT; 4 Gray [Gy]), 6 (60%) achieved a CR; among 5 lesions treated with full-dose radiotherapy (24-36 Gy), 4 (80%) achieved a CR. There were no local recurrences. Only one patient, treated with 30 Gy, developed an acute grade 3/4 toxic effect. There were no events of radiation-induced secondary malignancies. Our institutional experience indicates that radiotherapy, including VLDRT, is a safe and effective treatment for primary BALT lymphoma.

Development and validation of a CT-based radiomics model for differentiating pneumonia-like primary pulmonary lymphoma from infectious pneumonia: A multicenter study

BACKGROUND

Pneumonia-like primary pulmonary lymphoma (PPL) was commonly misdiagnosed as infectious pneumonia, leading to delayed treatment. The purpose of this study was to establish a computed tomography (CT)-based radiomics model to differentiate pneumonia-like PPL from infectious pneumonia.

METHODS

In this retrospective study, 79 patients with pneumonia-like PPL and 176 patients with infectious pneumonia from 12 medical centers were enrolled. Patients from center 1 to center 7 were assigned to the training or validation cohort, and the remaining patients from other centers were used as the external test cohort. Radiomics features were extracted from CT images. A three-step procedure was applied for radiomics feature selection and radiomics signature building, including the inter- and intra-class correlation coefficients (ICCs), a one-way analysis of variance (ANOVA), and least absolute shrinkage and selection operator (LASSO). Univariate and multivariate analyses were used to identify the significant clinicoradiological variables and construct a clinical factor model. Two radiologists reviewed the CT images for the external test set. Performance of the radiomics model, clinical factor model, and each radiologist were assessed by receiver operating characteristic, and area under the curve (AUC) was compared.

RESULTS

A total of 144 patients (44 with pneumonia-like PPL and 100 infectious pneumonia) were in the training cohort, 38 patients (12 with pneumonia-like PPL and 26 infectious pneumonia) were in the validation cohort, and 73 patients (23 with pneumonia-like PPL and 50 infectious pneumonia) were in the external test cohort. Twenty-three radiomics features were selected to build the radiomics model, which yielded AUCs of 0.95 (95% confidence interval [CI]: 0.94-0.99), 0.93 (95% CI: 0.85-0.98), and 0.94 (95% CI: 0.87-0.99) in the training, validation, and external test cohort, respectively. The AUCs for the two readers and clinical factor model were 0.74 (95% CI: 0.63-0.83), 0.72 (95% CI: 0.62-0.82), and 0.73 (95% CI: 0.62-0.84) in the external test cohort, respectively. The radiomics model outperformed both the readers' interpretation and clinical factor model ( P <0.05).

CONCLUSIONS

The CT-based radiomics model may provide an effective and non-invasive tool to differentiate pneumonia-like PPL from infectious pneumonia, which might provide assistance for clinicians in tailoring precise therapy.

Management of Extranodal Marginal Zone Lymphoma: Present and Upcoming Perspectives

Simple Summary

Extranodal marginal zone lymphoma distinguishes itself from other indolent lymphomas due to its unique pathophysiology and natural history. This is reflected in its management, where next to traditional treatment strategies such as observation, radiotherapy or chemotherapy, eradication of the causal agent and even surgery represent important aspects of therapy. This review focuses on the particular aspects of this indolent lymphoma that affect management and summarizes the current evidence and different guidelines.

Abstract

Extranodal marginal zone lymphoma (EMZL) encompasses a subgroup of non-Hodgkin lymphomas that often present with localized involvement and may manifest in a diversity of organs and tissues. EMZL pathogenesis is in some cases linked to chronic inflammation/infection, which may impose additional diagnostic and clinical challenges. The most studied and established connection is the presence of Helicobacter pylori in gastric EMZL. Due to its heterogeneity of presentation and intricate pathological features, treatment can be complex, and staging systems are decisive for the choice of therapy. Nevertheless, there is no consensus regarding the most suitable staging system, and recommendations vary among different countries. As a rule of thumb, in limited stages, a local therapy with surgery or radiation is the preferred option, and it is potentially curative. Of note, eradicating the causal agent may be an important step of treatment, especially in gastric EMZL, in which Helicobacter pylori eradication remains the first-line therapy for the majority of patients. In patients with more advanced stages, watch-and-wait is a valuable option, especially amongst those without clear indications for systemic therapy, and it may be carried on for several years. If watch-and-wait is not an option, systemic therapy may be needed. Even though several agents have been tested as monotherapy or in combination in recent years, there is no consensus regarding the first-line therapy, and decisions can vary depending on individual factors, such as age, clinical performance and stage. This review aims to discuss the several aspects of EMZL, including genetic milieu, pathogenesis and staging systems, that may influence the choice of therapy. In addition, we present a summary of evidence of several systemic therapies, compare different recommendations worldwide and discuss future perspectives and novelties in its therapy.

Clinical Features and Surgical Treatment of Primary Pulmonary Lymphoma: A Retrospective Study

Background

Primary pulmonary lymphoma (PPL) is a rare clonal lymphoproliferative lung disease. The present study analyzes the clinical features, imaging data, pathologic characteristics, treatment, and prognosis of PPL patients, with the aim to discuss the appropriate diagnosis and therapy of PPL patients in thoracic surgery.

Methods

We performed a retrospective analysis on 36 patients with PPL confirmed by postoperative pathology between 2006 and 2020. We divided the patients into low-stage (IE) and high-stage (IIE) groups using modified Ann Arbor staging. The clinical manifestations, imaging findings, treatment modalities, and outcomes were evaluated.

Results

The female to male ratio was 1.57:1 and the median age was 55 (31–69) years old. The majority of the patients had stage IE disease (75%; 27 of 36) and 9 patients had stage IIE disease. Patients with advancing stage were more likely to have respiratory symptoms. The imaging findings presented solid nodule or mass, pneumonia-like consolidative pattern, ground-glass opacity, and mixed pattern. There were 31 cases of mucosa-associated lymphoid tissue lymphoma (MALT), 2 diffuse large B-cell lymphoma (DLBCL), 2 nodular sclerosing Hodgkin’s lymphoma, and 1 marginal zone B-cell lymphoma. Two patients were diagnosed with PPL and non-small cell lung cancer (NSCLC) synchronously (one AIS and MIS and one lung adenocarcinoma). All the patients received surgery. Nine patients received adjuvant therapy after surgery (five radiotherapy, two chemotherapy, and two chemoradiotherapy). Thirty-four patients had a median follow-up time of 31 months (follow-up range: 7–152 months). Of the 34 patients, 1 patient died of liver metastases and 1 patient died of intestinal metastases.

Conclusions

Our retrospective analysis suggested that most PPLs were indolent and had favorable prognosis, but the discrimination of PPL with other lung diseases was difficult. Preoperative biopsy and intraoperative frozen section examination might help in the surgical choice. Limited lung resection was enough for peripherally localized PPL.

Two rare cases of bronchus-associated lymphoid tissue lymphoma successfully treated with rituximab-bendamustine

BALT lymphoma is a rare B-NHL with a favorable prognosis. We here report on two patients with nonspecific symptoms: one showed as major symptom severe thrombocytopenia and the other dyspnea and dry cough, thereby suggesting an inflammatory focus in the lungs. There is no standard of care established yet. Both patients were successfully treated with rituximab and bendamustine. Thus, combined immunochemotherapy should be considered as first-line therapy as in other MALT lymphomas, if the treatment/eradication of an underlying chronic inflammatory disorder/trigger factor can be excluded.

Decision-making in diagnosis of bronchus-associated lymphoid tissue lymphoma

Bronchus-associated lymphoid tissue (BALT) lymphomas of the lung are uncommon, and diagnosis is often delayed due to the indolent clinical course. Often, adequate samples are difficult to obtain by bronchoscopy with transbronchial biopsy alone. This retrospective study reviewed the diagnosis and treatment of BALT lymphoma cases at our institution over the course of 19 years. Most patients were white, women, and >50 years old; the mean Charlson Comorbidity Index at the time of diagnosis was 6. Seven of 12 patients presented with solitary nodules or multiple nodules. For six cases, initial modalities were nondiagnostic; four subsequently underwent surgical biopsy, one underwent computed tomography-guided biopsy, and one underwent navigational bronchoscopy for final diagnosis of BALT lymphoma. Ultimately, 55% of cases were diagnosed with nonsurgical biopsy. One patient suffered a pneumothorax related to the initial diagnostic attempt. Ten patients received chemotherapy, radiation, and/or surgery, and 11 of the 12 are still alive. Our data confirm the previously described indolent behavior of BALT lymphomas and the challenges related to diagnosis. While previous studies have suggested surgical biopsy as the primary modality for obtaining histopathology, navigational bronchoscopy could serve as a safer alternative.

Clinical and radiological characteristics of patients with pulmonary marginal zone lymphoma: A single center analysis

Pulmonary marginal zone lymphoma (PMZL) is the most common non‐Hodgkin lymphoma affecting the lung. PMZL is usually an indolent disease. Clinical and radiological variables associated with shorter survival are largely unknown and no consensus exists on preferred treatment strategy in PMZL. Herein we aimed to identify clinical and radiological features associated with shorter survival and inferior treatment outcomes. Forty patients with PMZL were analyzed. FDG‐avid disease was evident in most patients (93%) with staging PET/CT (n = 15). With a median follow‐up in treated patients (n = 38) of 8.4 years (range 0.07‐18.44), the median progression‐free survival (PFS) and overall survival (OS) were 7.5 years (95% CI 1.8‐9.5) and 15.7 years (95% CI 9.3‐NE) respectively. Shorter PFS was observed in patients who presented at diagnosis with elevated LDH, B symptoms, advanced stage and failed to achieve complete response (CR) after initial treatment. Patients with multifocal lung disease, extrapulmonary MZL and cavitary lesions on CT scans exhibited shorter PFS. Nevertheless, no clinical or radiologic findings were associated with shorter OS. All patients treated with surgery (n = 4) and radiation therapy (n = 3) achieved and remained in CR. No higher grade transformations occurred during the follow‐up period. PMZL exhibited excellent outcomes with a 15‐year PMZL‐related OS of 94.9% (95% CI: 81.25%‐98.7%). Radiation therapy and surgery are potentially curative strategies in localized PMZL.

Primary Pulmonary Diffuse Large B-Cell Lymphoma Presenting as an Endobronchial Lesion: The Youngest Adult Patient in the Literature

A 20-year-old female patient was admitted to hospital with complaints of chest and back pain in September 2018. There was a cavitary lesion in the upper zone of the left lung in the chest X-ray. Thorax CT revealed an irregular contoured and shaped mass with 87x67x79 mm sizes, in the upper lobe of the left lung lying to paramediastinal area. Since there was a doubt about malignancy, positron emission tomography (PET) was performed; there was a cavitary lesion in the left upper lobe with high FDG uptake (SUVmax: 23.2). Bronchoscopic examination revealed an endobronchial lesion with nearly complete occlusion in the apicoposterior segment of the left upper lobe. Bronchoalveolar lavage (BAL) performed in this session for acid-fast bacilli (AFB) was negative. The patient was diagnosed as primary pulmonary diffuse large B-cell lymphoma (DLBCL) by histopathological and immunohistochemical evaluation of endobronchial biopsy specimens. Following the final diagnosis of Bronchus-Associated Lymphoid Tissue Lymphoma (BALTOMA), the patient was referred to the department of haematology, and chemotherapy was planned for therapy. Since DLBCL is extremely rare, and uncommonly presenting with an endobronchial lesion, we want to present this patient as the youngest adult case of primary endobronchial BALT lymphoma in the literature.

Treatment outcomes in patients with extranodal marginal zone B-cell lymphoma of the lung

OBJECTIVES

To evaluate clinical presentations, treatment modalities, and outcomes of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma by stage strata.

METHODS

We retrospectively reviewed 51 patients diagnosed with pulmonary MALT lymphoma between January 2003 and December 2015. To compare treatment modalities and outcomes, we stratified the patients into low-stage (IE/IIE) and high-stage (IIIE/IVE) groups using modified Ann Arbor staging. Progression-free survival was estimated using Kaplan-Meier curves, and differences were compared using the log-rank test. A hazard ratio of progression by stage strata, adjusted for other clinical variables, was determined using a Cox adjusted proportional hazards model.

RESULTS

The majority of patients had stage IE disease (76.5%; 39 of 51). With advancing stage, patients were more likely to have respiratory and B symptoms and higher International Prognostic Index scores. The most common treatment modality was surgical resection in low-stage patients (33 of 43) and chemotherapy in high-stage patients (7 of 8). At a median follow-up of 40.7 months, progression-free survival was longer for low-stage patients (median, 40.7 months vs 24.9 months; P < .001), and high-stage patients were 9.2 times more likely to progress (hazard ratio, 9.24; 95% confidence interval, 1.93-44.36). Among 30 patients with surgically resected stage IE disease, 8 with central lesions were treated via lobectomy and 22 with peripheral lesions were treated via lobectomy (n = 8) or limited resection (n = 14). One of these patients, with a central lesion, experienced disease recurrence.

CONCLUSIONS

Our findings suggest that the clinical course of low-stage pulmonary MALT lymphoma, for which the mainstay of treatment is surgical resection, might be indolent.

Bronchus Associated Lymphoid Tissue Lymphoma Presenting with Immunodeficiency and Multiple Pulmonary Nodules

Bronchus Associated Lymphoid Tissue Lymphoma (BALTOMA) is a rare subgroup of pulmonary non-Hodgkin's lymphomas (NHLs) comprising less than 1% of all cases. It constitutes 3.6% of all extranodal lymphomas and only 0.5–1% of primary pulmonary malignancies. They are usually low grade B-cell lymphomas and are considered to originate from the mucosa associated lymphoid tissue (MALT) of the bronchi. Here, we represent a rare case of BALTOMA presenting with immunodeficiency and multiple pulmonary nodules.

Pulmonary mucosa-associated lymphoid tissue lymphoma revisited

This general review sought to clarify the pathophysiological, diagnostic, prognostic, and therapeutic features of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma.MALT lymphoma is the most common pulmonary B-cell lymphoma, which usually occurs in the context of acquired MALT. The disease is slow-growing with an asymptomatic chronic alveolar opacity visible on radiography. Diagnosis requires tissue samples that should be retrieved using minimally invasive techniques, such as bronchoscopy or computed tomography-guided biopsies. The pathophysiology includes cytogenetic abnormalities and autoimmune diseases, whereas an association with a chronic pulmonary infection is still suspected but not yet demonstrated. Disease prognosis is typically excellent and the current available treatments are discussed in this review, including the decision not to treat, surgery, and single- or double-agent chemotherapy.

Is there role of additional chemotherapy after definitive local treatment for stage I/II marginal zone lymphoma?: Consortium for Improving Survival of Lymphoma (CISL) study

Even though local stage (Ann Arbor stage I/II) marginal zone lymphoma (MZL) is well controlled with local treatment-based therapy, no data exist on the role of additional chemotherapy after local treatment for stage I/II MZL. Patients with biopsy-confirmed Ann Arbor stage I/II MZL (n = 210) were included for analysis in this study. Of these, 180 patients (85.7 %) were stage I and 30 (14.3 %) were stage II. Most patients (n = 182, 86.7 %) were treated with a local modality including radiation therapy or surgery and 28 (13.3 %) received additional systemic chemotherapy after local treatment. The overall response rate was 98.3 % (95 % CI 96-100 %), with 187 complete responses and 20 partial responses. In the local treatment group, the mean progression-free survival (PFS) was 147.4 months (95 % CI 126.7-168.1 months) and the overall survival (OS) was 188.2 months (95 % CI 178.8-197.7 months). In the additional chemotherapy group, the mean PFS was 103.4 months (95 % CI 84.9-121.9 months) and the OS was 137.3 months (95 % CI 127.9-146.7 months). There was no difference between the two groups in OS (p = 0.836) and PFS (p = 0.695). Local stage MZL has a good clinical course and is well controlled with a local treatment modality without additional chemotherapy.

Radical surgery may be not an optimal treatment approach for pulmonary MALT lymphoma

Primary pulmonary MALT lymphoma is a rare disease, and no standard treatments have been defined yet. In this study, 38 consecutive patients from single center were reviewed. Among 25 patients with localized disease, radical surgery were performed in 12 patients, and the other 13 patients had chemotherapy combined with (7 patients) or without (6 patients) radiotherapy. No significant difference in overall survival (OS) was found between patients who received surgery or not; however, patients treated with chemotherapy had superior progression-free survival (PFS) than those treated with upfront surgery (P = 0.032). Among the 12 patients who received radical surgery, 7 were given adjuvant chemotherapy and 1 patient had consolidation radiotherapy. No significant differences in PFS and OS exist between those who received adjuvant treatment or not (P > 0.05). For patients who received chemotherapy, PFS and OS were significantly better for those treated with cyclophosphamide-based therapy than fludarabine-based therapy. At a median follow-up time of 61.1 months, 5- and 10-year PFS rate was 70.0 and 43.0 %, respectively, and 5- and 10-year OS rate was both 81.0 %. In conclusion, we confirmed the indolent behavior and favorable outcome of this disease. In order to preserve lung function and reduce the risks associated with surgery, radiotherapy or rituximab in combination with alkylating drug-based chemotherapy should be considered as first-line option for pulmonary MALT lymphoma.

A Rare Case of Anaplastic Variant of Diffuse Large B-Cell Lymphoma Presenting as a Lung Primary

Primary pulmonary lymphoma is an uncommon neoplastic disorder representing approximately 0.5% to 1% of primary pulmonary malignancies. The vast majority are of low-grade, mucosa-associated lymphoid tissue type. Primary diffuse large B-cell lymphoma of the lung is rare, though cases of the centroblastic and immunoblastic variants have been described. We present herein an interesting case of an 80-year-old man who presented with both respiratory and constitutional symptoms and was found to have a 4.5 cm left hilar mass with bilateral hilar and mediastinal lymphadenopathy on imaging. Endobronchial biopsy revealed an aggressive large cell lymphoma, with scattered large, bizarre-shaped nuclei resembling Reed–Sternberg cells, positive for CD20, PAX5, CD30, and MUM-1, consistent with an anaplastic variant of diffuse large B-cell lymphoma. Imaging showed no evidence of extrathoracic disease. Standard treatment with cyclophosphamide/vincristine/prednisone and rituximab resulted in significant clinical and radiological response and the patient remains in remission 21 months later. To the best of our knowledge, this modified Ann Arbor stage II2E primary pulmonary lymphoma, is the first description in the English literature of anaplastic variant of diffuse large B-cell lymphoma presenting as a lung primary.

Lymphoproliferative neoplasms of the lung: a review

CONTEXT

Diagnosis and classification of lymphomas are based on the morphologic, immunologic, and genetic features that the lesional cells share with their normal B and T lymphocyte counterparts. Primary pulmonary lymphomas account for 0.3% of primary lung neoplasms and less than 0.5% of all lymphomas.

OBJECTIVE

To describe and summarize the clinical and histopathologic features of the primary pulmonary lymphoma and secondary involvement of the lung by lymphoma.

DATA SOURCES

Peer-reviewed published literature and personal experience.

CONCLUSIONS

Diagnosis of clonal lymphoid proliferations in the lung has evolved owing to the greater utility of molecular and flow cytometric analysis of tissue. Further studies are needed to best define the clinical and prognostic features, as well as search for targeted therapy for these patients with rare neoplasms.

Low-dose radiation treatment in pulmonary mucosa-associated lymphoid tissue lymphoma: a plausible approach? A single-institution experience in 10 patients

PURPOSE

To propose an alternative approach for treatment of pulmonary marginal zone lymphoma, using a very small radiation dose (2 × 2 Gy) delivered exclusively to tumor sites.

METHODS AND MATERIALS

Patients had localized pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma according to the World Health Organization classification. The 6-MV radiation treatments were delivered using tumor-limited fields, except in cases of diffuse bilateral involvement. Two daily fractions of 2 Gy were delivered to tumor-limited fields using a 6-MV linear accelerator.

RESULTS

Ten patients with pulmonary MALT lymphoma entered the study. All but 1 had localized tumor masses. The median follow-up was 56 months (range, 2-103 months). Complete remission or an unconfirmed complete remission was obtained in 60% of patients within the first 2 months, and two additional partial responses were converted into a long-term unconfirmed complete remission. All patients are well and alive, no local progression was observed, and the 5-year progression-free survival rate was 87.5% (95% confidence interval 49%-97%).

CONCLUSIONS

Our results suggest that extremely low radiation doses delivered exclusively to tumor sites might be a treatment option in pulmonary MALT lymphoma.

Bronchus-associated lymphoid tissue lymphoma stage IV with subsequent histologic transformation to an aggressive lymphoma: A case report

Introduction

Extranodal marginal B-cell lymphoma of bronchus-associated lymphoid tissue is a rare entity accounting for less than 1% of all lymphomas. We report a case of a low-grade bronchus-associated lymphoid tissue lymphoma stage IV with transformation to an aggressive large B-cell lymphoma.

Case presentation

A 59-year-old African-American man was incidentally found to have a bronchus-associated lymphoid tissue lymphoma involving the bilateral lower lobes of his lungs. In addition, bone marrow involvement was discovered. His course was indolent with only some mild respiratory symptoms. He received single agent treatment with rituximab. No evidence of progression was seen at the end of receiving this regimen. Two years after treatment our patient presented with B symptoms. Imaging now showed significant increase in the size of the lung masses with cavitation of the right lower lobe mass. A repeat transbronchial biopsy suggested transformation to an aggressive diffuse large B-cell lymphoma.

Conclusion

This case illustrates a rare bronchus-associated lymphoid tissue lymphoma stage IV with histologic transformation to an aggressive lymphoma. In addition, this rare case of transformation presented as a cavitary lesion.

[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.

[Six cases of pulmonary MALT lymphoma: a heterogeneous therapeutic management]

Pulmonary mucosa-associated lymphoid tissue lymphomas (PMALT) account for around 1% of lymphomas. Clinical and radiological presentations, and the treatment of six PMALT were collected from 1993 to 2008. All patients received chemotherapy before disease progression. Two patients had a lobectomy and one received thoracic radiotherapy. In 2008, all the patients were alive and three were in remission. A "watch and wait" strategy is widely accepted for stable, asymptomatic patients and patients with low tumour mass. Surgery may be proposed for symptomatic patients who have localised PMALT. When a chemotherapy treatment is to be suggested, chlorambucil-based chemotherapy is preferred. There may be room for rituximab alone or in combination, but this remains to be precisely defined. Several larger studies are currently ongoing to assess the role of monoclonal antibodies and chemotherapy in MALT lymphomas. Subgroup analysis should help us to define the optimal treatment for PMALT.

Pulmonary BALT lymphoma successfully treated with eight cycles weekly rituximab: report of first case and F-18 FDG PET/CT images

Extra marginal-zone lymphomas of the lung is a very rare tumor and it originates from bronchial-associated lymphoid tissue. A 68-yr-old woman presented with productive cough and dyspnea. A thorax computed tomography scan showed a 9 × 10 cm in size mass in the left lung and pleural effusion in the lower lobe of left lung. Positron emission tomography/computed tomography (PET/CT) revealed intense uptake foci at the upper and middle sites of left lung and slight uptake foci at the mediastinal lymph nodes which showed malignant involvement. After bronchoscopic biopsy, the diagnosis of pulmonary bronchial-associated lymphoid tissue (BALT) lymphoma was confirmed. At the end of the eight cycles weekly rituximab treatment, complete response was obtained by PET/CT findings. It is concluded that extended rituximab schedule is more effective and it would be beneficial to investigate the use of PET/CT in the diagnosis and evaluating of the treatment response of pulmonary BALT lymphoma.

Bronchus-associated lymphoid tissue (BALT) structure and function

Bronchus-associated lymphoid tissue (BALT) is a constitutive mucosal lymphoid tissue adjacent to major airways in some mammalian species, including rats and rabbits, but not humans or mice. A related tissue, inducible BALT (iBALT), is an ectopic lymphoid tissue that is formed upon inflammation or infection in both mice and humans and can be found throughout the lung. Both BALT and iBALT acquire antigens from the airways and initiate local immune responses and maintain memory cells in the lungs. Here, we discuss the development and function of BALT and iBALT in the context of pulmonary immunity to infectious agents, tumors, and allergens as well as autoimmunity and inflammatory diseases of the lung.

Non-gastric marginal zone B-cell lymphoma in Korea: clinical features, treatment, and prognostic factors

Marginal zone B-cell lymphoma (MZL) is the second most common subtype of non-Hodgkin's lymphoma in Korea (17.3%). Mucosa-associated lymphoid tissue (MALT) can develop in almost any organ as a result of exposure to a persistent stimulus, such as chronic infection or certain autoimmune processes. Under conditions of prolonged lymphoid proliferation, a malignant clone may emerge, which is followed by the development of a MALT lymphoma. Whereas MALT lymphoma of the stomach is the most common and the most extensively studied, we focus on non-gastric MZL studies conducted in Korea that highlight the most recent advances with respect to MZL definition, etiology, clinical characteristics, natural history, treatment approaches, outcomes, and prognostic factors. Moreover, we discuss current organ-specific considerations and controversies, and identify areas for future research.