Primary Mucosa-associated Lymphoid Tissue Lymphoma Research Articles

Linfoma não Hodgkin da Zona Marginal Extranodal Tipo MALT com Acometimento da Coluna Torácica: revisão Sistemática da Literatura e Relato de Caso em um Hospital Universitário no Brasil

Background: Primary bone lymphomas are rare, accounting for less than 1% of non-Hodgkin's lymphomas (NHL). Extranodal marginal zone non-Hodgkin lymphoma of mucosa-associated lymphoid tissue (MALT) arising in the vertebral spine is extremely rare, with only seven cases reported. Methodology: A systematic literature review was conducted on cases from 2012 to 2022 of extranodal marginal zone MALT lymphoma involving the vertebral spine and associated with spinal cord compression. Additionally, a case report from a university hospital in Rio de Janeiro is described. The study was approved by the Research Ethics Committee (approval number: 5.818.416). Searches were performed in SciELO, PubMed, and LILACS databases, using the Health Sciences Descriptors: ("Vertebral Body" OR Spine) AND ("Lymphoma B-Cell Marginal Zone" OR "MALT Lymphoma" OR "Lymphoma of Mucosa Associated Lymphoid Tissue" OR "Mucosa Associated Lymphoid Tissue Lymphoma"). Articles with full texts available in English or Portuguese were selected. Case Description: A 56-year-old female presented with right-sided back pain, progressing to right flank irradiation, lower limb weakness (LLLL), and constitutional symptoms. MRI revealed a solid extradural mass occupying two-thirds of the vertebral canal's diameter, displacing and compressing the dorsal cord to the left. A bone marrow biopsy confirmed infiltration. Laminectomy was performed, and histopathology identified stage IVB extranodal marginal zone MALT lymphoma. Adjuvant chemotherapy led to complete remission. Results and Discussion: The literature review uncovered two relevant case reports. The thoracic spine was the most commonly affected region, and LLLL weakness was the most frequent symptom, with normal laboratory results. Treatment typically involved surgical tumor removal combined with radiotherapy or chemotherapy. Recurrence occurred in both cases, but follow-up showed no evidence of disease. The clinical presentation and exam findings of the current patient were similar to those in the literature, though with bone marrow infiltration. Treatment was consistent with cases in the review, with no recurrence to date. Conclusion: This case represents an uncommon manifestation of primary extranodal marginal zone MALT lymphoma with spinal cord compression, distinguished by bone marrow infiltration—a feature not previously reported in the two cases found in the literature. The case may be considered within the same group of cases reviewed.

Primary MALT lymphoma of the breast: pathological and radiological characteristics.

Primary Mucosa-associated lymphoid tissue (MALT) lymphoma is a rare diagnosis in the breast, and clinical diagnosis based on radiological features is often challenging. This study aimed to evaluate the clinicopathological, and radiological characteristics of the patients diagnosed with primary breast MALT lymphoma. This study examined 18 cases of primary MALT lymphoma of the breast diagnosed at a single tertiary center between January 2002 to December 2020. Medical charts, radiological imaging and original pathology slides were reviewed for each case. All cases were female (gender assigned at birth) and presented with a palpable mass or an incidental imaging finding. Imaging presentation ranged from mammographic asymmetries, circumscribed masses, and ultrasound masses lacking suspicious features. Seventeen cases were biopsied under ultrasound; one received a diagnostic excision biopsy. Microscopic examination of the breast specimens demonstrated atypical small lymphocyte infiltration with plasmacytoid differentiation and rare lymphoepithelial lesions. Immunohistochemistry was performed in all cases and established the diagnosis. Most patients were treated with radiotherapy, and only three were treated with chemotherapy. The median follow-up period was 4years and 7.5months, and all patients were alive at the last follow-up. Primary MALT breast lymphomas are usually indolent and non-systemic, and local radiotherapy may effectively alleviate local symptoms. Radiological findings show overlap with benign morphological features, which can delay the diagnosis of this unusual etiology. Although further studies involving a larger cohort could help establish the clinical and radiological characteristics of primary breast MALT lymphomas, pathology remains the primary method of diagnosis. University Health Network Ethics Committee (CAPCR/UHN REB number 19-5844), retrospectively registered.

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

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. 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. 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). 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.

CT radiomics analysis discriminates pulmonary lesions in patients with pulmonary MALT lymphoma and non-pulmonary MALT lymphoma

PurposeThe aim of this study is to create and validate a radiomics model based on CT scans, enabling the distinction between pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma and other pulmonary lesion causes. MethodsPatients diagnosed with primary pulmonary MALT lymphoma and lung infections at Fuzhou Pulmonary Hospital were randomly assigned to either a training group or a validation group. Meanwhile, individuals diagnosed with primary pulmonary MALT lymphoma and lung infections at Fujian Provincial Cancer Hospital were chosen as the external test group. We employed ITK-SNAP software for delineating the Region of Interest (ROI) within the images. Subsequently, we extracted radiomics features and convolutional neural networks using PyRadiomics, a component of the Onekey AI software suite. Relevant radiomic features were selected to build an intelligent diagnostic prediction model utilizing CT images, and the model's efficacy was assessed in both the validation group and the external test group. ResultsLeveraging radiomics, ten distinct features were carefully chosen for analysis. Subsequently, this study employed the machine learning techniques of Logistic Regression (LR), Support Vector Machine (SVM), and k-Nearest Neighbors (KNN) to construct models using these ten selected radiomics features within the training groups. Among these, SVM exhibited the highest performance, achieving an accuracy of 0.868, 0.870, and 0.90 on the training, validation, and external testing groups, respectively. For LR, the accuracy was 0.837, 0.863, and 0.90 on the training, validation, and external testing groups, respectively. For KNN, the accuracy was 0.884, 0.859, and 0.790 on the training, validation, and external testing groups, respectively. ConclusionWe established a noninvasive radiomics model utilizing CT imaging to diagnose pulmonary MALT lymphoma associated with pulmonary lesions. This model presents a promising adjunct tool to enhance diagnostic specificity for pulmonary MALT lymphoma, particularly in populations where pulmonary lesion changes may be attributed to other causes.

A primary mucosa-associated lymphoid tissue (MALT) lymphoma of the bladder: recognising the zebra among the horses

A primary mucosa-associated lymphoid tissue (MALT) lymphoma of the bladder: recognising the zebra among the horses

Stromal area differences with epithelial-mesenchymal transition gene changes in conjunctival and orbital mucosa-associated lymphoid tissue lymphoma.

To examine the molecular biological differences between conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma and orbital MALT lymphoma in ocular adnexa lymphoma. Observational case series. A total of 129 consecutive, randomized cases of ocular adnexa MALT lymphoma diagnosed histopathologically between 2008 and 2020.Total RNA was extracted from formalin-fixed paraffin-embedded tissue from ocular adnexa MALT lymphoma, and RNA-sequencing was performed. Orbital MALT lymphoma gene expression was compared with that of conjunctival MALT lymphoma. Gene set (GS) analysis detecting for gene set cluster was performed in RNA-sequence. Related proteins were further examined by immunohistochemical staining. In addition, artificial segmentation image used to count stromal area in HE images. GS analysis showed differences in expression in 29 GS types in primary orbital MALT lymphoma (N=5,5, FDR q-value <0.25). The GS with the greatest difference in expression was the GS of epithelial-mesenchymal transition (EMT). Based on this GS change, immunohistochemical staining was added using E-cadherin as an epithelial marker and vimentin as a mesenchymal marker for EMT. There was significant staining of vimentin in orbital lymphoma (P<0.01, N=129) and of E-cadherin in conjunctival lesions (P=0.023, N=129). Vimentin staining correlated with Ann Arbor staging (1 versus >1) independent of age and sex on multivariate analysis (P=0.004). Stroma area in tumor were significant difference(P<0.01). GS changes including EMT and stromal area in tumor were used to demonstrate the molecular biological differences between conjunctival MALT lymphoma and orbital MALT lymphoma in ocular adnexa lymphomas.

Malignant mimicking primary mucosa-associated lymphoid tissue (MALT) lymphoma of the gallbladder; case

Malignant mimicking primary mucosa-associated lymphoid tissue (MALT) lymphoma of the gallbladder; case

Thymic mucosa-associated lymphoid tissue lymphoma in a patient with Sjögren’s syndrome with cutaneous vasculitis

Introduction. The association between Sj?gren?s syndrome (SS) and the development of lymphoma is well known. The prevalence of lymphoma in patients with SS is 5%. Mucosa-associated lymphoid tissue (MALT) lymphoma is the most common lymphoma type in patients with SS. It is common for MALT lymphoma to develop in the stomach, while it is extremely rare in the thymus. Case report. We present a 61-year-old Caucasian male patient with primary SS, cutaneous vasculitis, and thymic MALT lymphoma. The patient had a two-year history of diffuse cutaneous palpable purpura on legs, intermittently enlarged left parotid gland, and dry mouth. The results of Schirmer?s test were positive, labial salivary glands biopsy revealed a focus score ? 1, serology testing showed positive anti-Ro/SS-A and anti- La/SS-B antibodies, while skin biopsy findings revealed leukocytoclastic vasculitis. Diagnosis of primary SS with extraglandular cutaneous manifestations was confirmed. Cryoglobulinemia (Cg) and monoclonal gammopathy (MG) were detected, which increased the suspicion of hematological malignancy, and additional diagnostic procedures were performed. Computed tomography of the chest revealed an enlarged, multicystically altered anterior mediastinal mass. A thymectomy was performed through video-assisted thoracic surgery. Histological findings of the tissue confirmed the presence of tumor tissue consistent with MALT lymphoma in the thymus. Induction therapy with pulse doses of glucocorticoids was applied for three days, which was continued with medium doses of the drug. The doses were gradually reduced, and hydroxychloroquine was introduced. This has shown to be an effective therapy against features of SS. Postoperative local radiotherapy was performed. Conclusion. In SS patients with CV and in the presence of Cg and MG, attention should also be paid to the eventual development of MALT lymphoma, including the rare localization in the thymus.

Primary Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of the Prostate: MRI and FDG-PET Imaging Findings

Background: Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the prostate is a rare condition, and there is no report on magnetic resonance imaging (MRI) and its relationship with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET). Objectives: The purpose of this article is to present the MRI and FDG-PET imaging findings of primary MALT lymphoma of the prostate and discuss the imaging findings’ importance in the diagnosis and management. Case summaries: A 73-year-old male patient underwent a prostate biopsy for lower urinary tract symptoms and an elevated serum prostate-specific antigen level. Histopathologic and immunohistochemical findings were consistent with MALT lymphoma. As the tumor was confined to the prostate and adjacent tissues and no lymph node metastases were detected on PET-CT, the diagnosis was primary MALT lymphoma of the prostate. The tumor of the transitional zone infiltrated along the obturator internus muscle and into the pubic bone, the levator ani muscle was almost intact on MRI. Conclusion: The absence of lymph node metastasis or gross muscle destruction but a high degree of invasiveness into surrounding tissues is an important imaging finding in the diagnosis of primary MALT lymphoma of the prostate. Keywords: Differential Diagnosis; MRI; Prostate Neoplasms

Primary Mucosa-Associated Lymphoid Tissue Lymphoma of the Parotid Gland in 32-Year-Old Male, a Case Report

Primary lymphomas of the salivary gland are rare. The most common subtype is MALT lymphoma. MALT lymphoma has an indolent clinical course, and patients often present with a prolonged history. Evaluations of parotid masses begin initially with radiological imaging, but pathological and histological examination remains the mainstay of definitive diagnosis. This case describes a primary non-Hodgkin’s lymphoma of the parotid gland in a healthy 32-year-old male. This case report will evaluate the prevalence of primary MALT lymphoma and discuss the possible presentation.

Helicobacter pylori-negative mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach: A clinicopathologic analysis.

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is historically associated with Helicobacter pylori (HP) infections in more than 80% of patients. However, the incidence of HP-negative MALT lymphoma has been increasing. The clinicopathologic features have not been well studied, and optimal management strategies remain unclear. The pathology database was searched for primary gastric MALT lymphomas diagnosed from 2000 to 2017. The clinical data and the slides were reviewed. The cases were divided for analysis into those with a background of chronic gastritis with HP, chronic gastritis without HP, and without either a background of chronic gastritis or HP. Of 70 gastric MALT lymphoma cases identified, 26 (37% of total) had chronic gastritis and were positive for HP histologically (n = 23) or were HP positive by additional laboratory testing (n = 3). The remaining 44 (63% of total) cases were HP negative by histology. Within the HP-negative cases, 5 (11% of HP-negative cases) showed histologic gastritis while 39 (89% of HP-negative cases) did not have sufficient evidence of gastritis through review of slides (n = 18) or based on available pathology reports (n = 21). The HP-negative cases without gastritis had higher propensities to show a mass lesion on endoscopy compared with HP-positive cases (37.5% vs 11.1%, P = .02) at the initial diagnosis. The immunophenotype and rate of positive B-cell gene rearrangement were not significantly different between the 2 groups. While all HP-positive patients received antibiotics for HP eradication, treatment in the HP-negative group varied among antibiotics, radiation, rituximab, or chemotherapy. Among HP-negative patients with available follow-up, 13 (39%) showed disease recurrence, similar to the recurrence rate in HP-positive patients; however, no individual from either group has died of the disease thus far. The incidence of HP-negative MALT lymphoma is increasing, and in our practice, it is currently more common than HP-associated MALT lymphomas. The pathophysiology of HP-negative MALT lymphoma without chronic gastritis remains unclear. Follow-up data in our study suggest that the prognosis of these cases is excellent despite varied management modalities.

Primary rectal mucosa-associated lymphoid tissue lymphoma treated with only endoscopic submucosal dissection: A case report

Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct subtype of non-Hodgkin B cell lymphoma that mostly involves the gastrointestinal tract. The stomach is the most commonly affected site whereas colorectal involvement occurs very rarely. Given its rarity, the management and clinical outcome of colorectal MALT lymphoma are not well established yet. From the superficial capillary bed in the lower rectum. Endoscopic ultrasonography showed homogenous hypoechoic lesions in the deep mucosal layer. Endoscopic submucosal dissection (ESD) was done for accurate histologic diagnosis and treatment and both the rectal lesions were completely removed en bloc and subsequently diagnosed as primary rectal MALT lymphoma. Herein, we report a case of primary rectal MALT lymphoma in a 68-year-old woman that was treated by only ESD, and the 12-month follow-up revealed no tumour recurrence. These results of our case and previous reports suggest that endoscopic resection alone may be a feasible and safe treatment for primary colorectal MALT lymphoma and allows organ preservation.

Multipurpose ultrasonographic characteristics of primary uveal MALT lymphoma.

To investigate the ultrasonographic features in patients with primary uveal mucosa-associated lymphoid tissue (MALT) lymphoma. Medical records of 12 patients (13 eyes) diagnosed with primary uveal MALT lymphoma between September 2014 and September 2021 were retrospectively reviewed. Ultrasonography, B-scan ultrasonography, color Doppler flow imaging, and ultrasound biomicroscopy findings were retrieved from the medical records. Mean age of the included patients was 59.4 ± 8.6years. Typical ultrasonographic features of the choroidal infiltrates were flat, diffuse, and thickened, with low and homogenous internal reflectivity and with rich arterial blood flow from posterior ciliary arterioles. The mean thickness of the choroidal infiltrates was 1.34 ± 0.68mm (n = 13). Most of the affected eyes had posterior episcleral extensions, with a mean thickness of 1.66 ± 1.21mm (n = 12). Typical crescent-like posterior episcleral extensions were detected in nine eyes (69.2%). In six eyes, the blood flow from the choroidal infiltrates communicated with the episcleral extensions. In the ciliary body, the mean thickness of the infiltrates was 1.08 ± 0.43mm (n = 9), and seven eyes (77.8%) had 360° ring-like infiltrations. The initial best-corrected visual acuity (BCVA) was significantly correlated with the final BCVA after treatment (p < 0.001). Multipurpose ultrasonographic imaging revealed the unique characteristics of the primary uveal MALT lymphoma and is helpful in the diagnosis of this rare disease.

Primary hepatic extranodal marginal zone B-cell mucosa-associated lymphoid tissue lymphoma treated by laparoscopic partial hepatectomy: a case report

BackgroundPrimary hepatic extranodal marginal zone B-cell mucosa-associated lymphoid tissue (MALT) lymphoma is very rare, so it is difficult to diagnose preoperatively. And there is no established treatment for hepatic MALT lymphoma. We report herein a case of primary hepatic MALT lymphoma treated by laparoscopic partial hepatectomy, and discuss the usefulness of laparoscopic hepatectomy for a rare liver tumor.Case presentationThis patient was a woman in her 60s, who was diagnosed preoperatively as having synchronous liver metastasis from sigmoid colon cancer; therefore, laparoscopic partial hepatectomy was performed. She had a good course after the operation and was discharged on postoperative day 12. However, she was diagnosed pathologically as having primary hepatic MALT lymphoma. A bone marrow biopsy was also performed, and then she was finally diagnosed as having limited-stage primary hepatic MALT lymphoma. She received no postoperative treatment and showed no recurrence for 4 years postoperatively.ConclusionsWe experienced the good result of the patient with limited-stage primary MALT lymphoma treated by laparoscopic partial hepatectomy. Liver tumors are sometimes misdiagnosed by imaging examinations alone. Laparoscopic hepatectomy has been widespread recently as a minimally invasive procedure, and it may be useful for both diagnosis and treatment.

Role of Surgery in Patients with Stage IE Primary Thyroid MALT Lymphoma Staged by a Modified Classification System: The Tokyo Classification.

To establish the appropriate staging system and assess the role of curative thyroidectomy alone (Surgery) vs. involved-site radiation therapy after open biopsy (OB-ISRT) in stage IE mucosa-associated lymphoid tissue (MALT) lymphoma. We examined the Tokyo Classification as a modified classification. This retrospective cohort study included 256 patients with thyroid MALT lymphoma; 137 underwent standard therapy (i.e., OB-ISRT) and were enrolled for the Tokyo classification. Sixty stage IE patients with the same diagnosis were examined to compare Surgery with OB-ISRT. Overall survival (p = 0.0092) and relapse-free survival (0.00113) were significantly better in stage IE vs. stage IIE under the Tokyo classification. No OB-ISRT and Surgery patients died, but three OB-ISRT patients relapsed. The incidence of permanent complications was 28% in OB-ISRT (mainly dry mouth) and 0% in Surgery (p = 0.027). The number of painkiller prescription days was significantly greater in OB-ISRT (p < 0.001). During follow-up, the rate of the new appearance/change of the low-density area in the thyroid gland was significantly higher in OB-ISRT (p = 0.031). The Tokyo classification allows an appropriate discrimination between stages IE and IIE MALT lymphoma. Surgery can provide a good prognosis in stage IE cases; it also avoids complications, shortens painful periods during treatment, and simplifies ultrasound follow-up.

A Rare Case of Hepatic MALT Lymphoma with Coexistence of Hepatitis B Virus and Echinococcus Infection

Primary hepatic extranodal mucosa-associated lymphoid tissue (MALT) lymphoma is seen extremely rare compromising 0,016% among non-Hodgkin lymphomas. Association of chronic inflammatory conditions or infectious processes mostly hepatitis B virus (HBV) infection has been reported by scarce number of case presentations. Whereas MALT lymphoma accompanied by echinococcus granulosus infection was described only in one primary pulmonary lymphoma case. We herein present a primary hepatic MALT lymphoma case with both HBV carrier state and liver hydatid cyst history. A 86 years old male patient referred to our clinic with a sole liver mass and was diagnosed with primary hepatic MALT lymphoma by core biopsy. Positron emission tomography detected increased uptake in the liver lesion without any other uptake site. He was successfully treated with rituximab-chemotherapy, tenofovir and albendazole. By adding one more case to the literature we aimed to emphasize the probable etiologic causative role of echinococcus infection in MALT lymphoma.

Mucosal associated Lymphoid Tissue Lymphoma of the uvea: an analysis of 3 cases

BackgroundOcular mucosa-associated lymphoid tissue (MALT) lymphoma involving orbit and conjunctiva usually has an indolent clinical course with “salmon patch” mass as typical presentation. This study is to report a series of rare cases and investigate the clinical and pathological features of ocular MALT lymphoma that involved uveal tissue primarily and presented as posterior scleritis.MethodsThis retrospective, observational study was conducted at Beijing Tongren Hospital. From 2018 to 2020, 3 cases of 3 eyes (2 female patients and 1 male patient) with ocular MALT lymphoma that involved uveal tissue primarily and presented as posterior scleritis were included in the study. All patients had complaints of red eyes with blurred vision. The average age was 56.33 ± 2.08 years old and the average time from initial diagnosis to pathological diagnosis was 3.00 ± 1.73 months. Ophthalmic examinations including best-corrected visual acuity (BCVA), intraocular pressure (IOP), slit lamp microscope examinations, fundus photography, B-scan ultrasonography, ultrasound biomicroscope (UBM), optical coherence tomography (OCT), fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were conducted. Systemic workups including orbital magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT) and blood autoimmune antibody tests were also conducted. Pathological tissue from patients were obtained through surgeries. Biopsy examinations were performed to accurately determine pathological diagnosis. All the information of clinical, imaging and pathological changes were collected and analyzed.ResultsAt the initial diagnosis, the BCVA of involved eyes decreased seriously while the IOP were normal. All involved eyeball showed extensive hyperemia and local thickening in the wall of eyeballs. B-scan ultrasonography showed mass with abundant blood and irregular cysts inside the eyeball wall and in the retrobulbar orbit, surrounding the ocular wall and optic nerve. UBM showed solid lesions with low and medium echo under the conjunctiva and inside the ciliary body of 2 cases. OCT showed posterior polar wavy rise of RPE and local neuroepithelial detachment in all cases. FFA and ICGA showed vascular abnormalities (patch-like strong fluorescence and fluorescence leakage) and local thickening in retina and choroid (Rectangle-like weak fluorescence below the macula). The posterior wall of the eyeball was thickened and enhanced in MRI. PET-CT also showed thickening of posterior wall of eyeballs and increased metabolic activity but there was no sign of autoimmune disease. All patients were diagnosed as MALT lymphoma through pathologic examinations of biopsy tissue.ConclusionsThe onset of primary ocular MALT lymphoma in uvea is hidden. The early clinical manifestations are lack of specificity and misleading. B-scan ultrasonography has characteristic manifestations and is valuable in diagnosis. However, pathological diagnosis through tissue biopsy is irreplaceable.

Thymic Extranodal Marginal-Zone Lymphoma of Mucosa-Associated Lymphoid Tissue: Pathological Features, 18F-FDG PET/CT Findings and Prognosis in 12 Cases.

PurposePrimary thymic extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a rare type of MALT lymphoma. We aim to investigate the clinicopathologic features, 18F-FDG PET/CT findings and outcomes for patients with primary thymic MALT lymphoma; to explore the correlation between metabolic parameters and immunohistochemical phenotypes.MethodsA retrospective single-center study enrolled 12 patients with primary thymic MALT lymphoma between 2010 and 2021. Nineteen 18F-FDG PET/CT scans were performed, and clinicopathologic and immunohistochemical characteristics, PET/CT imaging features, and outcomes were analyzed.ResultsThe male-to-female ratio was 1. The median age at diagnosis was 40 (range 31–68). The long diameter of the lesions ranged from 3.5 to 15.7. Histopathological examinations revealed that the normal thymic lobular architecture was effaced by a diffuse lymphoid infiltrate, but residual Hassall corpuscles could still be identified, mostly with CD20+, PAX5+, CD3-, CD23-, CD10-, BCL-6-, cyclin D1-, EBER- and low Ki-67. The gene rearrangement indicated that the IGH gene but not TCR gene was found in 7 patients. Six initial PET/CT scans showed a mean SUVmax of 6.8 (range, 3.1–12.4), a mean MTV = 40.0 (range, 6.7–81.4), and a mean TLG = 144.3 (range, 19.7–286.4). During the follow-up period, there was no death except for the patient with DLBCL who died 59 months after diagnosis of primary thymic MALT. No significant correlation between SUVmax and Ki-67 index was observed (r = 0.355, P > 0.05).ConclusionPrimary thymic MALT lymphoma should be considered in patients with multilocular cystic lesions with different degrees of 18F-FDG uptake in the anterior mediastinum. The results of this study showed no correlation between SUVmax and Ki-67 index.

Primary mucosa-associated lymphoid tissue lymphoma of the entire esophagus diagnosed by endoscopic ultrasound-guided fine needle aspiration.

Primary mucosa-associated lymphoid tissue lymphoma of the entire esophagus diagnosed by endoscopic ultrasound-guided fine needle aspiration.

Primary oral mucosa-associated lymphoid tissue (MALT) lymphoma in patient with monoclonale gammopathy: a rare case report

BackgroundMonoclonal gammopathy is a biological reality encountered in approximately 1% of the general population. In the absence of clinical and biological signs, it is considered of undetermined significance; however, it can be a biological signature of a monoclonal lymphocytic or plasma-cell proliferation. Their localisation to the oral mucosa remains rare and difficult to diagnose, particularly in indolent forms that escape imaging techniques.Case presentationHere, we report the case of a 73-year-old woman with a history of IgM kappa gammopathy followed for 13 years. The patient did not have a chronic infection or an autoimmune disease, and all the biological investigations and radiological explorations were unremarkable during this period. The discovery of a submucosal nodule in the cheek led to the diagnosis of MALT lymphoma and regression of half of the IgM kappa level after resection. The review of the literature shows the dominance of clinical signs (i.e., a mass or swelling) in the diagnosis of primary MALT lymphomas of the oral cavity after surgical resection.ConclusionsOur case illustrates the role of examination of the oral cavity in the context of a monoclonal gammopathy. The absence of clinical and radiological evidence in favor of lymphoplasmacytic proliferation, does not exclude a primary indolent MALT lymphoma of the oral mucosa.