Development of malignant lymphoma in myoepithelial sialadenitis (Sjögren's syndrome)

Regression of Mucosa-Associated Lymphoid Tissue Lymphoma Arising From the Nonampullary Descending Part of the Duodenum by Treatment With Antibiotics in a Helicobacter pylori-Negative Patient

We report a 63-year-old male, Helicobacter pylori-negative patient with mucosa-associated lymphoid tissue (MALT) lymphoma of the second part of the duodenum that regressed after antibiotic treatment. Esophagogastroduodenoscopy (EGD) showed flat elevation with shallow depression on the contralateral side of the ampulla of Vater. The lesion was limited to the duodenal second part. The patient had a history of Helicobacter pylori positivity, with successful eradication at 41 years of age. Twelve months after vonoprazan (VPZ)-based antibiotic treatment, the duodenal lesion had obviously regressed, and the pathological diagnosis was complete histological response (ChR). This case suggests that certain bacteria may promote the development of duodenal MALT lymphoma.

The Genetic Landscape of Ocular Adnexa MALT Lymphoma Reveals Frequent Aberrations in NFAT and MEF2B Signaling Pathways

A comprehensive constellation of somatic non-silent mutations and copy number (CN) variations in ocular adnexa marginal zone lymphoma (OAMZL) is unknown. By utilizing whole-exome sequencing in 69 tumors we define the genetic landscape of OAMZL. Mutations and CN changes in CABIN1 (30%), RHOA (26%), TBL1XR1 (22%), and CREBBP (17%) and inactivation of TNFAIP3 (26%) were among the most common aberrations. Candidate cancer driver genes cluster in the B-cell receptor (BCR), NFkB, NOTCH and NFAT signaling pathways. One of the most commonly altered genes is CABIN1, a calcineurin inhibitor acting as a negative regulator of the NFAT and MEF2B transcriptional activity. CABIN1 deletions enhance BCR-stimulated NFAT and MEF2B transcriptional activity, while CABIN1 mutations enhance only MEF2B transcriptional activity by impairing binding of mSin3a to CABIN1. Our data provide an unbiased identification of genetically altered genes that may play a role in the molecular pathogenesis of OAMZL and serve as therapeutic targets.

Indicators for Malignant Transformation in Patients With Lymphoepithelial Lesion

PURPOSE

Salivary lesion (LEL) represents a unique disease, and some patients have malignant transformations. The study aims were to estimate the frequency of malignant transformation and the subtype of the malignant component and to identify factors associated with malignant transformation and subtype of the malignant component in patients with LEL.

PATIENTS AND METHODS

This study was based on a retrospective cohort study between 2005 and 2017 from patients who were diagnosed as LEL. The predictor variable was composed of a set of variables grouped into demographic, clinical, and pathologic features. The outcome variables were malignant transformation status and subtype of the malignant components. All parameters between the predictor variables and outcome variables were analyzed using the χ² test and a logistic regression model.

RESULTS

The sample was composed of 252 cases of LEL (including with or without malignant transformation) with a mean age of 50.3 years; 58 (58 of 252; 23.0%) were males, 194 (194 of 252; 77.0%) were females. The parotid gland was the most common site of LEL (206 of 252; 81.7%), and 36.5% (92 of 252) of the patients had a history of Sjögren syndrome (SS). Masses greater than 2 cm in diameter had evidence of malignant transformation (P < .001). Factors associated with the subtype of malignant components were a history of SS (P < .001) and Epstein-Barr virus infection. The percentages of nonmalignant transformations, LEL with extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma), and LEL progressing to lymphoepithelial carcinoma were 44.8 (113 of 252), 47.6 (120 of 252), and 7.6% (19 of 252), respectively.

CONCLUSIONS

More than half of cases have a malignant transformation, and MALT lymphoma is the most common malignant subtype. A larger mass (>2 cm) is an independent indicator of malignant transformation in LEL patients. History of SS among LEL patients is considered a risk factor for MALT lymphoma.

A Novel Proposal of Salivary Lymphocyte Detection and Phenotyping in Patients Affected by Sjogren's Syndrome

A preliminary evaluation of the parotid secretion cellular composition in patients with Sjogren’s Syndrome (SS) and a diagnostic accuracy assessment of salivary lymphocyte detection and immunophenotyping in Sjogren’s Syndrome diagnosis and prognosis were performed. The study included 40 consecutive patients, aged 19–60 years, with parenchymal sialadenitis associated with Sjogren’s Syndrome, and 20 healthy donors. The exclusion criteria were exacerbation of sialadenitis, chronic infections, malignant neoplasms, and lymphoproliferative diseases. The standard diagnostic tests were minor salivary gland biopsy and parotid sialography. Immunophenotyping of parotid secretion lymphocytes was performed by multicolor flow cytometry. Lymphocytes were detectable in parotid secretion of patients affected by Sjogren’s Syndrome, both primary (pSS) and secondary (sSS) form, but not in that from healthy donors. Sensitivity, specificity, positive, and negative predictive values of lymphocytes detection in parotid saliva were 77.5%, 100%, 100%, and 69%, respectively. The mean numbers of the total T-cell population, T-helper cells, and T-cytotoxic cells were 71.7%, 41.6%, and 53%, respectively. The immunophenotype of lymphocytes obtained by patients’ parotid flow resembles the immunophenotypes of glandular biopsies currently known. Our preliminary data suggest the use of saliva as an alternative and non-invasive method for evaluating the prognosis of Sjogren’s Syndrome.

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in the oromaxillofacial head and neck region: A retrospective analysis of 105 patients

Background

Extranodal marginal zone B‐cell lymphoma of mucosa‐associated lymphoid tissue (MALT lymphoma) in the oromaxillofacial head and neck region is rare, with limited data available. This retrospective study explored the clinical features, stage, treatment, and prognosis of this disease.

Methods

Overall, 105 patients with MALT lymphomas in the oromaxillofacial head and neck region were included in this retrospective analysis. SPSS 22.0 software package was used for data analysis and a two‐tailed P value of ≤.05 was considered statistically significant. Primary endpoints of the study were the complete response (CR) rate, overall survival (OS), and progression‐free survival (PFS).

Results

About 52% of the patients had long‐term xerostomia, autoimmune diseases, or chronic parotitis and 81% had diseases involving the large salivary glands. Ann Arbor staging of the patients was as follows: stages I/II, 73 patients and stages III/IV, 32 patients. In the 97 patients followed up, CR rate after initial treatment was 80%. Tumor progression was observed in 12 patients and 14 patients died. There was a significant difference between the rate of CR in localized (87%) and disseminated (67%) lymphoma patients (P = .02). The 5‐ and 10‐year PFS of the localized lymphoma patients were both 91%, whereas those of the disseminated lymphoma patients were 83% and 65%, respectively (P = .03). The 5‐year PFS rates of the chemotherapy and non‐chemotherapy groups in the disseminated lymphoma patients were 85% and 73% (P = .04). Meanwhile, the 5‐year PFS rates of the rituximab and non‐rituximab groups in the disseminated lymphoma patients were 100% and 70% (P = .03). In multivariate analysis, MALT Lymphoma International Prognostic Index (MALT‐IPI) was an independent prognostic factor affecting OS, whereas Ann Arbor staging affected PFS.

Conclusions

This study suggests that the outcome after initial treatment of MALT lymphomas in the oromaxillofacial head and neck region is satisfactory and that this disease progresses slowly. The CR rate and PFS of localized lymphoma patients are better than those of disseminated lymphoma patients. Systemic treatment (chemotherapy or rituximab) may improve PFS in disseminated disease patients. MALT‐IPI and Ann Arbor staging are independent prognostic factors.

Multimodality fMRI with perfusion, diffusion-weighted MRI and 1 H-MRS in the diagnosis of lympho-associated benign and malignant lesions of the parotid gland

BACKGROUND

Differential diagnosis of the mucosa-associated lymphoid tissue lymphoma (MALToma) and tumor-like benign lymphoepithelial lesion (BLEL) in the parotid gland is difficult.

PURPOSE

To distinguish MALToma and BLEL with multimodality MRI including hydrogenproton magnetic resonance spectroscopy (¹ H-MRS), diffusion-weighted imaging (DWI-MR), and dynamic contrast-enhanced (DCE-MR), and evaluate each sequence.

STUDY TYPE

Retrospective.

POPULATION

Twenty-five patients with parotid tumor-like BLEL and 20 with parotid MALToma.

FIELD STRENGTH/SEQUENCE

1.5-T/T₁ WI, T₂ WI, single-voxel ¹ H-MRS, DWI-MR, and DCE-MR.

ASSESSMENT

All MR images were interpreted and agreed upon by two radiologists who were blinded to clinical information and histopathologic results. The imaging diagnoses were then compared to the histopathologic results.

STATISTICAL TESTS

Youden index was used to determine the optimized threshold value. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficiency of different functional (f)MRI methods.

RESULTS

Fisher's exact test indicated a significant difference between the ¹ H-MRS images of the two lesions (P < 0.001). The sensitivity, specificity, and accuracy of positive choline (Cho) peak in ¹ H-MRS of parotid MALToma were 80%, 76%, and 77.7%, respectively. The mean apparent diffusion coefficient (ADC) was 0.992 × 10^-3 mm² /s in patients with parotid tumor-like BLEL and 0.634 × 10^-3 mm² /s in patients with parotid MALToma, and the difference was statistically significant (t-test, P < 0.001). Choosing the Youden index as 0.669 × 10^-3 mm² /s, the sensitivity, specificity, and accuracy of the assay were 78.9%, 95.8%, and 88.4%, respectively. Assuming that time-intensity curve (TIC) type I indicated parotid MALToma (positive), and type II and type III indicated parotid tumor-like BLEL (negative), the sensitivity, specificity, and accuracy of time-to-peak (TTP) and initial slope of increase (ISI) in diagnosing MALToma were 94.1%, 95.2%, and 94.7%, respectively. Combining methods of TTP, ADC, and Cho peak reached the highest AUC (1.000).

DATA CONCLUSION

Combined use ¹ H-MRS, DWI-MR, and DCE-MR increased the accuracy of the differential diagnosis between these lesions to 100%. Cho peak in ¹ H-MRS, ADC less than 0.669 × 10^-3 mm² /s, TIC type I together indicated parotid MALToma.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:423-432.

Primary Malignant Lymphoma of the Salivary Glands

Five cases of primary malignant lymphomas of the salivary glands are reported. Four lymphomas arose in the parotid gland and one in the submandibular gland. All were non-Hodgkin lymphomas. In 4 cases the lymphomas were of low-grade malignancy, viz. 2 immunocytomas and 2 centroblastic/centrocytic malignant lymphomas, and 1 was a T-immunoblastic malignant lymphoma of high-grade malignancy. Four patients with localized disease were treated with radiotherapy and 1 patient with disseminated disease was treated with chemotherapy. One patient died from a disease unrelated to the malignant lymphoma, and 4 patients were alive at 66-136 months after treatment.

Prominent Plasmacytic Differentiation in the Recurrence of a Parotid Immunocytoma. A Morphologic and Immunohistochemical Study

We report and discuss a case consisting of 2 lesions that developed at different times in the same parotid gland. Although the first lesion showed morphologic features similar to those of the benign lymphoepithelial lesion, a monotoypic IgM/K pattern was also revealed by the immunoperoxidase method in its lymphoid infiltrates. Thus, on cytologic grounds, the first lesion was classified as lymphoplasmacytic immunocytoma (according to Kiel criteria). In the second lesion, which recurred 3 years later, the prominent feature was a marked predominance of plasma cells with the same monoclonal IgM/K as the preceding lymphoma. These findings suggests that a B-lymphomatous cell monoclone may undergo morphologic maturation along the lineage of its competence. Secondly, they indicate that every case of benign lymphoepithelial lesion of the salivary glands should undergo thorough immunologic evaluation to exclude the possibility of signs of precocious lymphomatous transformation.

Küttner’s Tumor of Salivary Glands Resembling Marginal Zone B-cell Lymphoma of the MALT Type: A Histopathologic and Immunohistochemical Study of 7 Cases

Küttner’s tumor is a benign inflammatory process of the submandibular gland that presents as a hard mass mimicking a malignant neoplasm clinically. The histologic feature varies according to stage of evolution and severity of inflammation. We report here 7 cases of Küttner’s tumor that morphologically resemble primary salivary gland marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type. Histologically, the lobular architecture was distorted and the septa showed sclerosis. There was a dense lymphoplasmacytoid infiltration with lymphoid follicle formation accompanied by loss of acini and ducts. In 4 cases, a few salivary gland ducts contained the lymphoid cells within the epithelium. However, a true lymphoepithelial lesion was observed in none of the 7 cases. Immunohistochemical study demonstrated a disrupted follicular dendritic cell network, which is a characteristic finding of follicular colonization of MALT-type lymphoma. In 6 cases, there were a few small foci of lymphocytes somewhat resembling centrocyte-like cells of MALT-type lymphoma. However, immunohistological study demonstrated the mixed nature of the cells resembling centrocyte-like cells. Moreover, the polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction.

Primary rectal mucosa-associated lymphoid tissue lymphoma in a patient with previously identified primary biliary cirrhosis and secondary Sjögren's syndrome

An 83-year-old female began treatment with prednisolone and ursodeoxycholic acid at 62 years of age, following a diagnosis of primary biliary cirrhosis (PBC) and secondary Sjögren’s syndrome (SjS). With persisting bloody stools, the patient underwent colonoscopy at 83 years of age. Histopathological evaluation revealed mucosa-associated lymphoid tissue (MALT) lymphoma. The elevated rectal lesion resolved with rituximab treatment. We report this case because although patients with SjS are at increased risk of malignant lymphoma, primary rectal MALT lymphoma is very uncommon in association with PBC and secondary SjS.

Extranodal Marginal Zone Lymphoma of the Parotid Gland

Non Hodgkin lymphomas correspond to 25 % of all head and neck cancers. These rare tumors only include less than 5 % of malign tumors in parotid region. Differential diagnosis of these tumors cover many malign and benign tumors of the parotid gland. Definite diagnosis depends on sufficient tissue material of parotidectomy specimen. Treatment modality is surgical removal of the lesion with or without additional radiation and chemotherapy depending on the stage of the tumor. Prognosis is better than other forms of the B-cell lymphoma. We present a 54 year old woman who suffered from progressively and slowly growing mass on parotid region, without any inflammatory disease or chronic infection, diagnosed with mucosa associated lymphoid tissue lymphoma of the parotid gland. Parotid gland was totally excised by superficial parotidectomy and there is no recurrence after 5 years postoperative period.

Dynamic contrast-enhanced MR in the diagnosis of lympho-associated benign and malignant lesions in the parotid gland

OBJECTIVE

The aim of this study was to determine if dynamic contrast-enhanced (DCE)-MRI can differentiate mucosa-associated lymphoid tissue (MALT) lymphoma from benign lymphoepithelial lesion (BLEL) in the parotid gland.

METHODS

25 patients with tumour-like BLEL and 20 patients with MALT lymphoma in the parotid gland confirmed by pathology were examined pre-operatively using routine MR series and DCE-MRI with a 1.5-T MR unit. The time to peak (TTP), time to start (TTS), SIstart, SImax and SIending were measured and the initial slope of increase (ISI) and relative washout ratio (RWO) were calculated separately from the time-intensity curve (TIC), and the types of TIC were analysed.

RESULTS

There were significant differences in the TTP and ISI between the two lesions (p < 0.001). The sensitivity, specificity and accuracy of TTP were all more than 90%. TICs were divided into three types according to the threshold of TTP and ISI: tumour-like BLEL: gradual type (Type II) and late increase type (Type III); MALT lymphoma: rapid increase and gradual type (Type I).

CONCLUSIONS

DCE-MRI contributed greatly to the differential diagnosis between tumour-like BLEL and MALT lymphoma in the parotid gland.

Molecular Pathogenesis of MALT Lymphoma

Approximately 8% of all non-Hodgkin lymphomas are extranodal marginal zone B cell lymphoma of mucosa associated lymphoid tissue (MALT), also known as MALT lymphoma, which was first described in 1983 by Isaacson and Wright. MALT lymphomas arise at a wide range of different extranodal sites, with the highest frequency in the stomach, followed by lung, ocular adnexa, and thyroid, and with a low percentage in the small intestine. Interestingly, at least 3 different, apparently site-specific, chromosomal translocations and missense and frameshift mutations, all pathway-related genes affecting the NF-κB signal, have been implicated in the development and progression of MALT lymphoma. However, these genetic abnormalities alone are not sufficient for malignant transformation. There is now increasing evidence suggesting that the oncogenic product of translocation cooperates with immunological stimulation in oncogenesis, that is, the association with chronic bacterial infection or autoaggressive process. This review mainly discusses MALT lymphomas in terms of their genetic aberration and association with chronic infections and summarizes recent advances in their molecular pathogenesis.

Thymic hyperplasia with lymphoepithelial sialadenitis (LESA)-like features: a clinicopathologic and immunohistochemical study of 4 cases

Four cases of an unusual type of thymic hyperplasia strongly resembling lymphoepithelial sialadenitis (LESA) of the salivary glands are described. The patients were 2 men and 2 women aged 37 to 53 years. On histologic examination, abundant lymphoid tissue with lymphoid follicles containing germinal centers and areas of plasma cell infiltration were seen. The epithelial component consisted of a proliferation of Hassall corpuscles and islands of thymic epithelial cells. Cystic changes and lymphoepithelial lesions were identified in all cases, but a monocytoid B-cell population was absent. On immunohistochemical examination, a mixed B- and T-cell population was identified, and polymerase chain reaction performed in 1 case showed polyclonality. Follow-up revealed that all patients were alive 5 months to 9 years after diagnosis. The cases in this series represent a distinct type of thymic hyperplasia that histologically strongly resembles LESA. The clinicopathologic and immunohistochemical features are presented, and a possible relationship with thymic mucosa-associated lymphoid tissue (MALT) lymphoma is discussed.

Biased use of the IGHV4 family and evidence for antigen selection in Chlamydophila psittaci-negative ocular adnexal extranodal marginal zone lymphomas

Extranodal marginal zone lymphomas (EMZL) are the most common lymphomas in the ocular adnexa. The etiology and potential role for antigenic stimulation in these lymphomas are still controversial. We have examined IGHV gene usage and mutations in 67 Chlamydophila psittaci-negative ocular adnexal EMZL. Clonal IGHV gene sequences were identified in 43 tumors originating from the orbit (19), conjunctivae (18) and lacrimal gland (6). Forty four potentially functional clonal IGHV gene sequences were detected with overrepresentation of the IGHV4 family and IGHV4-34 gene. All but 3 sequences were mutated with the average percent homology to the germ line of 93.5±6.1. Multinomial model and Focused binomial test demonstrated evidence for positive and/or negative antigen selection in 59% of the potentially functional IGHV genes. Intraclonal variation was detected in 8 of 11 tumor specimens. Overall our findings demonstrate that C. psittaci-negative ocular adnexal EMZL exhibit biased usage of IGHV families and genes with evidence for intraclonal heterogeneity and antigen selection in multiple tumors, implicating B-cell receptor-mediated antigen stimulation in the pathogenesis of these lymphomas.

Submandibular gland MALT lymphoma associated with Sjögren's syndrome: case report

Lymphoma is a common disease of the head and neck. Mucosal-associated lymphoid tissue (MALT) lymphoma constitutes a rare type of extranodal lymphoma. The Waldeyer's ring is one of the most common sites of occurrence, but MALT lymphoma may also arise in salivary glands, lung, stomach, or lacrimal glands. In the oral cavity, it may be confused with swellings from dental infection or sinus inflammation. Often, the patient will seek a dentist because of mobile teeth or because a denture no longer fits. We report a case of a female patient with salivary gland dysfunction and pain of several years' duration, who, after numerous tests and hospitalizations, was diagnosed with Sjögren's syndrome. She later developed mucosal-associated lymphoid tissue lymphoma. We discuss the diagnosis, treatment, and prognosis of this entity. MALT lymphoma is rare in salivary glands. In primary-Sjögren's syndrome, predisposition of the patient for development of malignant non-Hodgkin's lymphoma (4% to 10%) is well established. In this case, long-standing sialadenitis and Sjögren's syndrome seem to be the etiological factors. In cases of chronic infection of salivary glands and the presence of autoimmune syndromes, MALT lymphoma should be considered in the differential diagnosis. Consults should be called to ophthalmology, rheumatology, and head and neck oncologists for proper workup, staging, and treatment.

Küttner's tumor of the sub-mandibular gland associated with fibrosclerosis and follicular hyperplasia of regional lymph nodes: a case report

Introduction

Küttner's tumor is characterized through histology by peri-ductal fibrosis, dense lymphocytic infiltration with lymphoid follicles, loss of acini, and occasional marked sclerosis of the salivary gland. On occasion, Küttner's tumor can be difficult to distinguish from malignant neoplasm.

Case presentation

A 58-year-old Japanese man was referred to our hospital with a three-month history of a painless swollen mass in the right sub-mandibular region. Histological findings revealed both lymphoid follicles with reactive germinal centers and variously sized lymphoid follicle-like nodules without definitive germinal centers or mantle zones. B-cells of similar size and shape occupied the lymphoid follicle-like nodules and stained positive for B-cell lymphoma. These cells were detected in the polyclonal B-cells by flow cytometric analysis and tested negative for CD10. Unusual B-cell proliferation was observed, but as there was no definitive evidence of B-cell lymphoma, the lesion was diagnosed as Küttner's tumor.

Conclusion

We report on a rare case of Küttner's tumor associated with fibrosclerosis and atypical lymphoid hyperplasia in both the sub-mandibular gland and regional lymph nodes. Although more cases need to be investigated, our findings might be helpful to further studies seeking to clarify the etiology of idiopathic sclerosing lesions arising in the organs and regional lymph nodes.

Pulmonary Manifestations in Sjögren’s Syndrome: Correlation Analysis Between Chest Computed Tomographic Findings and Clinical Subsets with Poor Prognosis in 80 Patients

Objective.

Sjögren’s syndrome (SS) has a varied clinical spectrum and has been associated with various chest computed tomography (CT) findings. We sought to delineate the characteristic CT features in various subsets of SS, especially poor prognosis subsets.

Methods.

Retrospectively identified 80 never-smoker SS patients [56 primary SS (1-SS), 24 secondary SS (2-SS)] who underwent chest CT at our institution during a 3-year period from 2004 through 2007 were included in this study. Chest CT findings were qualitatively and semiquantitatively analyzed with comparison between 1-SS and 2-SS, and correlation with anti-SSB/La seropositivity and the presence of clonally derived lymphoproliferative disorder (cLPD), which are known to be pathognomonic and prognostic clinical features of SS patients.

Results.

All patients were women with median age of 60 years. Anti-SSB/La antibodies were found in 17 primary SS patients and 4 2-SS patients. Eleven patients with cLPD were identified and all of them had 1-SS. The most frequent CT finding in both types of patients was interlobular septal thickening. Secondary SS was associated with a significantly greater frequency and extent of honeycombing versus 1-SS. Univariate and multivariate analysis showed a significant association between honeycombing and 2-SS. In patients with 1-SS and in the SS group as a whole, we observed independent and significant associations between cysts and anti-SSB/La seropositivity or cLPD.

Conclusion.

Cysts are significantly associated with anti-SSB/La seropositivity and cLPD. The presence of lung cysts revealed by chest CT might be a prognostic clinical feature, a clue, or a predictor of cLPD in patients with SS.

Mucosa-associated lymphoid tissue lymphoma in Sjögren's syndrome: risks, management, and prognosis

Sjögren's syndrome is a chronic inflammatory disease primarily affecting the exocrine glands. Its association with lymphoma is well documented, with salivary extranodal marginal zone lymphomas of the mucosa-associated lymphoid tissue type being the most common and constituting a major disease complication. These neoplasms are antigen-stimulated B-cell lymphomas characterized by localized stage, indolent clinical course, and recurrence in other extranodal sites. This article presents a review of the literature and discusses the clinical, histopathologic, therapeutic, and prognostic aspects of these tumors in Sjögren's syndrome. In addition, it highlights the predictor markers of lymphoma development.

The influence of the NOD Nss1/Idd5 loci on sialadenitis and gene expression in salivary glands of congenic mice

The nonobese diabetic (NOD) Nss1 and Idd5 loci have been associated with sialadenitis development in mice. In this study the NOD Nss1 and Idd5 loci were backcrossed onto the healthy control strain B10.Q by using the speed congenic breeding strategy, resulting in three congenic strains: B10.Q.Nss1, B10.Q.Nss1/Idd5 heterozygous and B10.Q.Nss1/Idd5 homozygous. We investigated the effects of the Nss1 and Idd5 loci on sialadenitis and gene expression in NOD congenic mice. One submandibular salivary gland from each mouse was used for histological analysis of sialadenitis, whereas the contralateral salivary gland was used for gene expression profiling with the Applied Biosystems Mouse Genome Survey chip v.1.0. The results were validated using quantitative reverse transcriptase PCR. The NOD Nss1 and Idd5 loci had clear influence on the onset and progression of sialadenitis in congenic mice. Double congenic mice exhibited the most severe phenotype. We successfully identified several genes that are located in the NOD congenic regions to be differentially expressed between the congenic strains and the control strain. Several of these were found to be co-regulated, such as Stat1, complement component C1q genes and Tlr12. Also, a vast contingency of interferon-regulated genes (such as Ltb, Irf7 and Irf8) and cytokine and chemokine genes (such as Ccr7 and Ccl19) were differentially expressed between the congenic strains and the control strain. Over-representation of inflammatory signalling pathways was observed among the differentially expressed genes. We have found that the introgression of the NOD loci Nss1 and Idd5 on a healthy background caused sialadenitis in NOD congenic mouse strains, and we propose that genes within these loci are important factors in the pathogenesis. Furthermore, gene expression profiling has revealed several differentially expressed genes within and outside the NOD loci that are similar to genes found to be differentially expressed in patients with Sjögren's syndrome, and as such are interesting candidates for investigation to enhance our understanding of disease mechanisms and to develop future therapies.

Clinical, immunologic, and molecular factors predicting lymphoma development in Sjogren's syndrome patients

Among autoimmune diseases, Sjogren's syndrome (SS) displays the highest incidence of non-Hodgkin lymphoma (NHL) development with the salivary extranodal marginal zone B cell lymphomas being the most common type. The majority of SS-associated NHLs are characterized by localized stage, indolent clinical course, and recurrence in other extranodal sites. Although the transition from a chronic inflammatory condition to malignant lymphoma is a multistep process yet poorly understood, there is increasing evidence that chronic antigenic stimulation by an exoantigen or autoantigens plays an essential role in the development of SS associated lymphoproliferation. Additional molecular oncogenic events such as microsatellite instability, loss of the B cell cycle control, and the forced overproduction of specific B cell biologic stimulators seem to contribute to the emergence and progression of the malignant overgrowth. Among the clinical and serological parameters that have been associated with lymphoma development in SS patients, the presence of palpable purpura, low C4, and mixed monoclonal cryoglobulinemia constitute the main predictive markers, and patients displaying these risk factors should be monitored closely.

Do salivary antibodies reliably reflect both mucosal and systemic immunity?

Two major antibody classes operate in saliva: secretory IgA (SIgA) and IgG. The former is synthesized as dimeric IgA by plasma cells (PCs) in salivary glands and is exported by the polymeric Ig receptor (pIgR). Most IgG in saliva is derived from serum (mainly via gingival crevices), although some is locally produced. Gut-associated lymphoid tissue (GALT) and nasopharynx-associated lymphoid tissue (NALT) do not contribute equally to mucosal PCs throughout the body. Thus, enteric immunostimulation is an inadequate mode of stimulating salivary IgA antibodies, which are poorly associated with the intestinal SIgA response, for instance after enteric cholera vaccination. Nevertheless, the IgA response in submandibular/sublingual glands is better related to B cell induction in GALT than the parotid response. Such disparity is suggested by the elevated levels of IgA in submandibular secretions of AIDS patients, paralleling their highly upregulated intestinal IgA system. Moreover, in patients with active celiac disease, IgA antibodies to disease-precipitating gliadin are reliably represented in whole saliva but not in parotid secretion. Parotid SIgA may be more consistently linked to immune induction in palatine tonsils and adenoids (human NALT), as supported by the homing molecule profile of NALT-derived B cell blasts. Also several other variables influence the levels of antibodies in oral secretions. These include difficulties with reproducibility and standardization of immunoassays, the impact of flow rate, acute or chronic stress, protein loss during sample handling, and uncontrolled admixture of serum-derived IgG and monomeric IgA. Despite such problems, saliva remains an interesting biological fluid with great scientific and clinical potentials.

Distribution of intermediate filaments and actin microfilaments in parotid autoimmune sialoadenitis of Sjögren syndrome

In order to study the importance of myoepithelial cells in the formation of parotid epi-myoepithelial islands of the autoimmune sialoadenitis in Sjögren's syndrome, the distribution of cytoskeletal elements has been investigated by electron and immunofluorescence microscopy. Antibodies to intermediate filament proteins--prekeratins, desmin and vimentin--were used as well as a 'DNase I/anti-DNase I' immunohistochemical procedure to detect actin microfilaments for characterization of myoepithelial cells compared to the other types of parotid epithelial cells. Two types of prekeratin antibodies were raised. One of these reacted preferentially with myoepithelial cells. The same type of antiserum also showed a bright fluorescence in cells located peripherally in the epi-myoepithelial islands. These island cells, however, exhibited only a very low actin microfilament content and were thus not ordinary myoepithelial cells. The other type of prekeratin antibodies reacted with all types of parotid epithelia, except acinar secretory epithelium. They also stained all island epithelial cells, but the reactivity was less in cell regions with pronounced lymphocyte infiltration. The heterogeneity between the island epithelial cells, immunohistochemically as well as ultrastructurally, indicates different stages of island formation. Interepithelial lymphocytes showed less vimentin and actin filament content in comparison with lymphoid cells outside the islands. Conclusively, typical epi-myoepithelial islands are composed of metaplastic epithelial cells of intercalated duct origin and invaded lymphoid cells, and ordinary myoepithelial cells are lacking.

Lymphoma of the ocular adnexa: A study of 353 cases

We studied the cases of 353 patients with lymphoma involving the ocular adnexa diagnosed at the Massachusetts General Hospital between 1974 and 2005. The patients included 153 males and 200 females, aged 7 to 95 years, with a mean age of 64 years. In 277 cases, there was no known history of lymphoma. Seventy-six patients had a history of lymphoma, with the ocular adnexa being involved at relapse or with progression of the previously diagnosed lymphoma. The patients had marginal zone lymphoma (182 cases), follicular lymphoma (80 cases), mantle cell lymphoma (18 cases), small lymphocytic lymphoma/chronic lymphocytic leukemia (13 cases), lymphoplasmacytic lymphoma (4 cases), splenic marginal zone lymphoma (2 cases), low-grade B cell, not subclassified (19 cases), precursor B lymphoblastic lymphoma (3 cases), diffuse large B-cell lymphoma (26 cases), and 1 case each of high-grade B-cell lymphoma, not subclassified, peripheral T-cell lymphoma, unspecified type, extranodal NK/T-cell lymphoma, nasal type, and Hodgkin lymphoma, nodular sclerosis type. Almost all marginal zone lymphoma patients (168 of 182, 92%) had primary ocular adnexal lymphoma. Fourteen marginal zone lymphoma patients (8%) had a prior history of lymphoma, usually arising in another extranodal site. Twenty-five of 80 (31%) follicular lymphoma patients had a prior history of lymphoma, usually arising in lymph nodes. Patients with mantle cell lymphoma, chronic lymphocytic leukemia, lymphoplasmacytic lymphoma, and splenic marginal zone lymphoma almost always had a prior history of lymphoma or were known to have widespread disease at the time of diagnosis of ocular adnexal lymphoma. A subset of the diffuse large B-cell lymphomas were associated with large destructive masses involving adjacent structures such as paranasal sinuses, raising the possibility that they may have arisen from one of the adjacent structures and involved the ocular adnexa by direct extension. The relatively high proportion of low-grade lymphoma, not subclassified, highlights the difficulty that may arise in distinguishing different types of low-grade lymphoma, particularly when biopsies are small and artifactually distorted. Ocular adnexal lymphoma is primarily a disease of older adults, with a slight female preponderance. Most lymphomas are low-grade B-cell lymphomas, with marginal zone lymphoma being by far the most common type. Marginal zone lymphoma typically involves the ocular adnexa primarily, whereas other types of low-grade B-cell lymphoma often involve the ocular adnexa secondarily. High-grade B-cell lymphomas only occasionally involve the ocular adnexa, and T-cell lymphoma, NK-cell lymphoma, and Hodgkin lymphoma are only rarely encountered in this site.

Extranodal lymphomas of the head and neck

Malignant lymphomas represent approximately 5% of all malignant neoplasms of the head and neck and may involve nodal or extranodal sites. Nodal head and neck lymphomas are similar to other nodal sites and are not further reviewed here. The head and neck region is the second most frequent anatomical site of extranodal lymphomas (after the gastrointestinal tract). Most are non-Hodgkin's lymphomas of B-cell lineage, and overall diffuse large B-cell lymphoma is the most common type. Hodgkin's lymphoma rarely occurs in extranodal sites. Other hematologic neoplasms that commonly involve extranodal sites of the head and neck are also discussed. In this review, we begin by discussing lymphomas involving the head and neck according to anatomical site. Then we discuss specifically the pathological findings of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, plasmablastic lymphoma, extramedullary plasmacytoma, and extranodal natural killer/T-cell lymphoma of nasal type.

Küttner's tumor: unusual presentation with bilateral involvement of the lacrimal and submandibular glands

Chronic sclerosing sialadenitis, known as Küttner's tumor (KT), is a chronic inflammatory disease of the salivary gland characterized by progressive periductal fibrosis, dilated ducts with a dense lymphocyte infiltration and lymphoid follicle formation, and acinar atropy. We report a unique case of KT in a 30-year-old female who presented with time-serial involvement of the bilateral lacrimal and submandibular glands with reactive follicular hyperplasia of bilateral upper cervical lymph nodes. All tissue samples of the submandibular and lacrimal glands were typical of KT on pathologic examination. There was no evidence of lymphoepithelial lesions or intraepithelial lymphocytes. This is the first case of KT involving both lacrimal and submandibular glands, suggesting that KT is closely related to an active local immune process.

Lymphoproliferative disorders in Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic organ-specific autoimmune disease characterized by lymphocytic infiltration into the salivary and lacrimal glands. About half of primary SS patients develop systemic disorders. Primary SS can be divided into three stages according to the extent of organ damage and the course of the disease. In stage I, (approx. 45% of cases), patients have only sicca syndrome and do not experience any systemic involvement, even after 10 years. In stage II (approx. 50% of cases), patients experience lymphocytic organ damage, which may involve the pulmonary, renal, hepatic, hematologic, and/or dermatologic systems, among others. Finally, in stage III (approx. 5% of cases), patients develop malignant lymphomas. Lymphomas in salivary glands are thought to arise from lymphoepithelial lesions in which there are close interactions among epithelial cells, T cells, and B cells. The B cells in the lesions become activated through the interaction between CD40L and CD40. The progression from polyclonal lymphoproliferation to monoclonal lymphoproliferation, to mucosa-associated lymphoid tissue (MALT) lymphoma, and finally to high-grade malignant lymphoma is regarded as a multi-step process. Antigenic activation of B cells, together with oncogenic events, including p53 inactivation and bcl-2 activation, may play important roles in B cell monoclonal proliferation and malignant transformation. The rheumatoid factor clone is regarded as a candidate B cell clone that undergoes transformation.

Sclerosing variant of follicular lymphoma arising from submandibular glands and resembling "Küttner tumor": a report of 3 patients

We present 3 patients with a sclerosing variant of follicular lymphoma that arose from the submandibular gland and resembled "Küttner tumor." All 3 patients developed a painless unilateral tumor in the submandibular region. Histologically, all 3 lesions were categorized as follicular lymphoma grade 2. The neoplastic follicles were found to be separated by thick connective tissue, and periductal chronic inflammation with periductal fibrosis and duct ectasia was found in the residual atrophic gland. Immunohistochemistry revealed that all of the lesions contained a monoclonal tumor cell population. The immunophenotyopes of the lymphoma cells were CD 10+, CD 20+, CD 79a+, BCL-6+, CD 3-, CD 5-, CD 21-, CD 23-, CD 43-, CD 45RO-, BCL-2-, and Cyclin D1-. Two of the 3 patients exhibited clonal bands for the IgH gene by polymerase chain reaction assay. "Küttner tumor," which is a common fibrosing, chronic inflammatory lesion of the submandibular gland, is sometimes diagnosed as a malignant tumor. This study indicates that this sclerosing variant of follicular lymphoma should be added to the list of different diagnoses for "Küttner tumor."

Primary extranodal marginal zone B-cell lymphoma of the fallopian tube

BACKGROUND

Only 2% of all extranodal primary lymphomas affect the female genital tract. Involvement of the fallopian tubes by primary lymphoma is extremely rare.

CASE

A 34-year-old patient presented with the symptoms of salpingitis. Laparoscopy with salpingectomy was performed. Salpingitis caused by Acinetobacter species was diagnosed and antibiotic treatment was administered. Histologic examination of the fallopian tube revealed primary extranodal marginal zone B-cell lymphoma (MALT-type lymphoma) of the fallopian tube. After 12 months no tumoral recurrence occurred.

CONCLUSION

Although the female genital tract is rich in mucosa and the existence of mucosa-associated lymphoid tissue (MALT) has been demonstrated previously, extranodal marginal zone B-cell lymphoma of the fallopian tube is exceptional. To our knowledge only two cases with extranodal marginal zone B-cell lymphoma of the fallopian tube have been previously reported. Existence of inflammation close to the tumor is interesting to emphasize.

Marginal zone B-cell lymphoma of the salivary gland arising in chronic sclerosing sialadenitis (Küttner tumor)

We report a case of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type of the salivary gland arising in a background of chronic sclerosing sialadenitis. Chronic sclerosing sialadenitis is a common fibrosing chronic inflammatory lesion of the submandibular gland, which is thought to be the result of sialolithiasis, and is not associated with a systemic autoimmune disease. Salivary MALT lymphomas are typically associated with lymphoepithelial sialadenitis (LESA) in a patient with or without Sjögren's syndrome. Our case of salivary MALT lymphoma was neither preceded by Sjögren's syndrome nor accompanied by LESA. This case suggests that chronic inflammatory processes other than Sjögren's syndrome may provide a substrate for the development of MALT lymphoma.

Follicular lymphoma of the salivary gland: a clinicopathological and molecular study of six cases

To clarify the clinicopathologic, immunohistologic, and genotypic features of follicular lymphoma arising from the salivary glands, we examined 20 cases of operatively resected primary salivary gland lymphoma and identified 6 such cases. There were 4 women and 2 men with ages ranging from 38 to 64 years (median 50 years). The tumor arose from the parotid gland in 4 cases and the submandibular gland in the remaining 2. Four patients were stage IE and 2 were stage IIE-1. The median follow-up period was 49 months and all patients were alive and well at the time of going to press. Histologically, 5 patients were follicular lymphoma grade 2, and 1 was grade 3. In all specimens in noninfiltrating salivary gland tissue, there was periductal lymphocytic infiltration near the lymphoma. Moreover, myoepithelial sialoadenitis was noted in 2 lesions. An immunohistochemical study revealed all 6 cases were CD10+, CD79a+, bcl-6+, CD3-, CD5-, CD21-, CD23-, and CyclinD1-. The tumor cells expressed bcl-2 in 3 cases and p53 oncoprotein in 4 cases. Two cases revealed clonal bands with polymerase chain reaction (PCR) assay for the immunoglobulin heavy (IgH) gene. The bcl-2/IgH translocation at the major breakpoint region was detected in 1 case (16%). We found a relatively high incidence of follicular lymphomas (30%) in salivary gland lymphomas. Among the mucosa-associated lymphoid tissue (MALT) system, follicular lymphomas appeared to occur frequently in the salivary glands as well as the duodenum and skin. Moreover, follicular lymphoma arising from the salivary glands appeared to have some of the characteristics of MALT-type lymphoma including indolent prognosis, presence of myoepithelial sialoadenitis, and rarity of the BCL-2 gene rearrangement.

Inflammatory pseudotumor of the submandibular gland: report of a case presenting with autoimmune disease-like clinical manifestations

We report a rare case of inflammatory pseudotumor arising in the submandibular gland, which presented with autoimmune disease-like clinical manifestations. A 70-year-old Japanese man developed masses in both submandibular regions. Laboratory tests revealed polyclonal hypergammaglobulinemia, high titers of antinuclear antibody, and a positive thyroid test. Histologically, the lesion was composed of multiple nodules separated by thick fibrous bands and contained a few atrophic lymphoid follicles and residual ductal structures. At higher magnification, the nodules contained numerous mature plasma cells mixed with myofibroblasts, lymphocytes, and histiocytes. Occasionally, the myofibroblasts were arranged in poorly formed fascicles and in a storiform pattern. Polymerase chain reaction analysis failed to demonstrated the rearrangement of the immunoglobulin heavy-chain gene. The patient was free of disease after 72 months follow-up. Marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type arising from salivary glands occasionally showed prominent plasma cell differentiation. The present case indicates that inflammatory pseudotumor should be added to the list of different diagnoses for mucosa-associated lymphoid tissue-type lymphoma of the salivary glands.

Pathological features of lymphoid proliferations of the salivary glands: lymphoepithelial sialadenitis versus low-grade B-cell lymphoma of the malt type

Lymphoid proliferations of the salivary glands can be either reactive or neoplastic. Reactive lesions include the lymphoepithelial sialadenitis (LESA; also known as myoepithelial sialadenitis [MESA]) of Sjogren's syndrome. Lymphomas of the salivary glands are predominantly B-cell type and include extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type. The spectrum of histopathologic features of LESA/MESA includes 1) "fully benign lymphoid infiltrate," with or without an associated lymphoid follicular structure, without immunoglobulin (Ig) light chain restriction in B-cells, and without any features of aggressive behavior, and 2) "lymphoproliferative lesions," with or without areas of Ig light chain restriction in B-cells, with the usual presence of centrocyte-like cells. A more or less pronounced lymphoepithelial aggressiveness may be present without definite evidence of malignancy. B-cell clones are detected in over 50% of cases of LESA/MESA by molecular genetic methods, but this does not correlate with morphological or clinical evidence of overt lymphoma. On the other hand, "marginal zone B-cell lymphoma of the MALT type" of the salivary glands produces a dense lymphoid infiltrate diffusely involving the gland, with obliteration of acini. The centrocyte-like cells form broad "halos" around the epithelial cell nests and broad strands between lymphoepithelial lesions, often linking together several lymphoepithelial lesions. Further, lymphoma cells express monotypic surface Ig, and in the majority of the cases, the plasma cells are also monoclonal. In conclusion, the diagnosis of LESA/MESA versus marginal zone B-cell lymphoma of the MALT type still relies on the evaluation of morphological features. It seems that molecular genetic analysis has little or no practical role in the clinical diagnosis of salivary gland lymphoma in a setting of LESA/MESA and Sjögren's syndrome.

Fine-needle aspiration cytology of lymphoproliferative lesions involving the major salivary glands

Fine-needle aspiration biopsy (FNA) is an accurate and cost-effective procedure for evaluating salivary gland lesions. Lymphoproliferative lesions may manifest as salivary gland enlargement. We report our experience with 43 cases of reactive and neoplastic lymphoproliferative lesions of the salivary glands evaluated by FNA, including 23 cases of reactive lymphoid hyperplasia and 20 neoplastic lymphoproliferative processes. The latter included 2 multiple myelomas and 18 non-Hodgkin lymphomas (small lymphocytic lymphoma/chronic lymphocytic leukemia, 1; small cleaved cell lymphoma, 1; lympho-plasmacytoid lymphoma, 1; mucosa-associated lymphoid tissue lymphoma, 2; mixed cell lymphoma, 4; lymphoblastic lymphoma, 1; and large cell lymphoma, 8). There were no false-negative diagnoses. Aspiration smears from 3 patients with reactive lymphoid hyperplasia and 4 patients with malignant lymphoma initially were interpreted as atypical lymphoid proliferations or as suggestive of malignant lymphoma. Thus, FNA had a sensitivity of 100% and a specificity of 87%. The majority of patients were treated medically without surgical intervention. Among the patients who underwent surgical resection of the salivary gland, 7 had an equivocal cytologic diagnosis and 2 had a benign cytologic diagnosis, but their parotid swelling failed to regress despite medical treatment. In most instances, FNA provides useful information for subsequent disease management and obviates surgical intervention.

Sjögren's syndrome: autoimmune epithelitis

Sjögren's syndrome (SS) is a chronic autoimmune disorder of the exocrine glands of unknown aetiology, which is typically associated with focal lymphocytic infiltrates of glandular tissues and autoantibody responses against the Ro(SSA) and La(SSB) ribonucleoproteins. In almost one-third of patients disease involves various extraglandular sites, whereas approximately 5% of patients may also develop malignant B-cell lymphoma. In addition, features of SS are frequently encountered (5-20%) in patients with several other autoimmune rheumatic diseases, and in several respects these 'secondary' forms may be distinct from SS found alone (primary-SS), as well as from each other. The correct diagnosis and management of SS may require consideration from various specialists. Differential diagnosis includes adverse effects of drugs, sarcoidosis, lipoproteinaemias, age-related atrophy, chronic graft-versus-host disease, lymphomas, amyloidosis and infection by human immunodeficiency virus or hepatitis C virus. Based on the sequential application of the validated European classification criteria for SS, a practical algorithm for diagnosis is presented. Despite progress in the understanding of the broad clinicopathological spectrum of the entity, its treatment remains largely empirical and symptomatic. To date, the decision for systemic therapeutic intervention is primarily based on the severity of extraglandular manifestations.

[Primary pleural lymphoma after collapse therapy: modern aspects of an historic disease]

INTRODUCTION

Pleural lymphomas after long standing pyothorax due to pulmonary tuberculosis are now well identified. Most cases have been described by Japanese investigators and it seems rare or unrecognised in Western countries. We report the study of six cases observed in a single institution.

PATIENTS AND METHODS

Six pyothorax-associated pleural lymphomas, among 1,038 lymphoma (0.6%) collected during a period from 1989 to 1998, are described. Diagnosis was established by two pathologists with the usual histologic and immunohistochemical methods, according to the working formulation. The in situ hybridization method for Epstein-Barr virus was performed.

RESULTS

The average age of the patient was 73 years. Presenting symptoms combined chest pain and constitutional symptoms more than 45 years after artificial pneumothorax or tuberculous pleuritis. Computerized tomography revealed a pleural mass which involved the adjacent chest wall. Open biopsy by thoracotomy show a diffuse B-cell non-Hodgkin-lymphoma in all cases. Though the lymphoma was initially localized, many poor prognostic factors (age, performance status, LDH, histology) explain the pejorative evolution (average survival of five months). Patients died from an uncontrolled tumoral proliferation or by infectious complications. In situ hybridization confirms the presence of Epstein-Barr virus in tumoral cells.

CONCLUSION

Pleural lymphoma is an established complication of artificial pneumothorax. Even if the Epstein-Barr virus plays a crucial role in the pathogenesis, and despite the number of artificial pneumothorax operations that have been widely performed, this lymphoma remains rare, suggesting additional oncogenic factors.

Sjögren's syndrome

Sjögren's syndrome is a rather common autoimmune disease primarily characterized by the dysfunction and destruction of exocrine glands associated with lymphocytic infiltrations. The disorder has a quite broad clinical presentation, ranging from glandular disease to systemic involvement and to the development of lymphoid malignancy. This article reviews the current aspects in clinical diagnosis and management and the immunopathogenesis of the disorder.

Malignant lymphoma in primary Sjögren's syndrome: a multicenter, retrospective, clinical study by the European Concerted Action on Sjögren's Syndrome

OBJECTIVE

Several reports have noted an increased incidence of malignant lymphoma in patients with Sjögren's syndrome (SS). Each case series has consisted of a limited number of patients with malignant non-Hodgkin's lymphoma (MNHL). In this report, we describe the disease characteristics, the clinical course, and the evolution in 33 patients followed up in 9 European medical centers.

METHODS

The pool of MNHL patients from participating centers in a European Concerted Action on SS were analyzed. We report on the disease characteristics, its evolution, prognosis, current treatment practices, and survival.

RESULTS

The MNHLs in this study were primarily situated in the marginal zone (48.5%), with the manifestations mostly extranodal (78.8%) and most often identified in the salivary glands (54.6%). Lymphadenopathy (65.6%), skin vasculitis (33.3%), peripheral nerve involvement (24.2%), low-grade fever (25.0%), anemia (48.1%), and lymphopenia (78.6%) were observed significantly more frequently than in the general SS population. Patients with high-to-intermediate grade lymphoma had significantly worse survival (P = 0.041). The presence of B symptoms (fever, night sweats, and weight loss) and a large tumor diameter (>7 cm) were additional independent risk factors for death.

CONCLUSION

The novel observations of this study were those related to the type of MNHL, the survival prognosis, and the very high frequency of skin vasculitis, peripheral nerve involvement, anemia, and lymphopenia. Some of the previously reported results on extranodal manifestations were confirmed.

Lymphoma development in Sjögren's syndrome: novel p53 mutations

OBJECTIVE

Sjögren's syndrome (SS) is a chronic autoimmune disease characterized by lymphocytic infiltrations of the exocrine glands. Disease progression may lead to uncontrolled clonal proliferation of B lymphocytes and development of lymphoma. This study was undertaken to examine the possible involvement of the cell cycle checkpoint genes p53 and p21 in the pathophysiology of the syndrome.

METHODS

Protein expression of p53 and p21 was studied, by immunohistochemistry and Western blot analysis, in minor salivary gland (MSG) biopsy specimens from 7 patients with SS and 5 control subjects. In addition, sequence analysis of the p53 gene was performed on DNA samples obtained from MSG biopsy samples of the same 7 patients with SS and from 4 patients with SS and in situ non-Hodgkin's lymphoma (NHL).

RESULTS

The study revealed increased protein expression of p53 and p21 in MSG biopsy specimens from patients as compared with controls, while sequence analysis showed that the p53 gene was of the wild type. Furthermore, sequence analysis of the p53 gene from patients with SS and in situ NHL revealed 2 novel mutations in exon 5 of the p53 gene. These mutations are single-base substitutions and appear to be functional since exon 5 is included in the coding region of the p53 gene.

CONCLUSION

This is the first report on wild-type p53 gene activation in SS. Our findings indicate a probable role for the DNA damage response genes in the pathogenesis of this syndrome. The novel mutations of the p53 gene implicate dysregulation of this tumor suppressor gene as a possible mechanism for lymphoma development in SS.

Bilateral and multicystic major salivary gland disease: a rare presentation of primary Sjögren's syndrome

We present a case of a 15-year-old girl with bilateral parotid and sub-mandibular salivary gland enlargement as the sole presentation of primary Sjögren's syndrome. The clinical, radiological, immunological and pathological features have been discussed. The relevant literature has been reviewed. To our knowledge this is the only reported case of Sjögren's syndrome presenting as multicystic disease with bilateral major salivary gland involvement.

Low-grade pulmonary mucosa-associated lymphoid tissue lymphoma with or without intraclonal variation

We examined the immunoglobulin heavy chain variable (Ig VH) region genes of 11 low-grade pulmonary mucosa-associated lymphoid tissue (MALT) lymphomas by a two-step polymerase chain reaction (PCR) and sequencing analysis. We observed frequent somatic mutations with the positive selective pressure of the rearranged Ig VH genes in all cases, indicative of postgerminal center cell origin. Eight cases demonstrated intraclonal variations (hypermutation with intraclonal variation type), but the other cases showed only one major clone without intraclonal heterogeneity (hypermutation without intraclonal variation type). The former might reflect the reentry of marginal zone B cells into a germinal center environment leading to further mutations. The latter might be no longer susceptible to hypermutation mechanisms and seemed to be stable. Four cases used Ig VH genes (hv3019b9, VH26, and VH4.21), which are frequently found in a variety of autoantibodies, such as cold agglutinins, rheumatoid factors, and anti-DNA antibodies.

B-cell lymphoma of mucosa-associated lymphoid tissue of the thymus: a report of two cases with a background of Sjögren's syndrome and monoclonal gammopathy

Two rare cases of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) arising in the thymus are reported. Both patients (a 61-year-old man and a 75-year-old woman) were suffering from Sjögren's syndrome and immunoglobulin (Ig)A kappa monoclonal gammopathy. Mixed IgA-IgG cryoglobulinemia was also present in the male case. Tumor cells expressed IgA and kappa antibody reactive proteins identical with serum IgA kappa M. Moreover, we could demonstrate rearrangements of the immunoglobulin heavy and light chain genes, which supported the monoclonal origin of tumor cells. Immunological abnormalities improved after thymectomy in one case in which the tumor cells were confined to the thymus, but not the other with regional lymph node involvement, suggesting a causal role for the tumor. MALT lymphomas of the thymus thus appear to be associated with immunological disorders such as Sjögren's syndrome or monoclonal gammopathy.

The epidemiology of non-Hodgkin's lymphoma: comparison of nodal and extra-nodal sites

International population-based cancer incidence data, coded according to the International Classification of Diseases for Oncology (WHO, 1990), were used to describe geographical patterns of incidence of extra-nodal non-Hodgkin's lymphomas. Incidence data from the USA were also used to describe age and sex distribution of lymphomas at different extranodal sites. The percentage of all non-Hodgkin's lymphomas coded as being of extra-nodal origin is between 25% and 35% in most countries, with the stomach, skin and small intestine being the most common extra-nodal sites. In general, the pattern of incidence rates for extra-nodal lymphomas tends to reflect that of other lymphomas. For example, the age incidence curve of each site-specific extra-nodal lymphoma is similar to that of nodal lymphomas, and in countries where total lymphoma incidence is high the incidence of lymphomas at each extra-nodal site also tends to be relatively high. Although specific factors are known to increase the risk of lymphomas at certain anatomical sites, these data suggest that the aetiology of extra-nodal lymphomas is not entirely independent from that of nodal lymphomas.

The epidemiology of non-Hodgkin's lymphoma: comparison of nodal and extra-nodal sites

International population-based cancer incidence data, coded according to the International Classification of Diseases for Oncology (WHO, 1990), were used to describe geographical patterns of incidence of extra-nodal non-Hodgkin's lymphomas. Incidence data from the USA were also used to describe age and sex distribution of lymphomas at different extranodal sites. The percentage of all non-Hodgkin's lymphomas coded as being of extra-nodal origin is between 25% and 35% in most countries, with the stomach, skin and small intestine being the most common extra-nodal sites. In general, the pattern of incidence rates for extra-nodal lymphomas tends to reflect that of other lymphomas. For example, the age incidence curve of each site-specific extra-nodal lymphoma is similar to that of nodal lymphomas, and in countries where total lymphoma incidence is high the incidence of lymphomas at each extra-nodal site also tends to be relatively high. Although specific factors are known to increase the risk of lymphomas at certain anatomical sites, these data suggest that the aetiology of extra-nodal lymphomas is not entirely independent from that of nodal lymphomas.