Mucosa-associated lymphoid tissue lymphoma of the salivary glands occurring in patients affected by Sjögren's syndrome: report of 6 cases

CD4+ Cytotoxic T Cells Involved in the Development of EBV-Associated Diseases

Activated cytotoxic CD4 T cells (HLA-DR+) play an important role in the control of EBV infection, especially in cells with latency I (EBNA-1). One of the evasion mechanisms of these latency cells is generated by gp42, which, via peripherally binding to the β1 domain of the β chain of MHC class II (HLA-DQ, -DR, and -DP) of the infected B lymphocyte, can block/alter the HLA class II/T-cell receptor (TCR) interaction, and confer an increased level of susceptibility towards the development of EBV-associated autoimmune diseases or cancer in genetically predisposed individuals (HLA-DRB1* and DQB1* alleles). The main developments predisposing the factors of these diseases are: EBV infection; HLA class II risk alleles; sex; and tissue that is infiltrated with EBV-latent cells, forming ectopic lymphoid structures. Therefore, there is a need to identify treatments for eliminating cells with EBV latency, because the current treatments (e.g., antivirals and rituximab) are ineffective.

Mantle cell lymphoma, malt lymphoma, small lymphocytic lymphoma, and follicular lymphoma of the oral cavity: An update

BACKGROUND

Although uncommon, mature small B-cell lymphomas may arise in the oral/maxillofacial area and oral pathologists must be aware of the key characteristics of these neoplasms to perform an accurate diagnosis. In this manuscript, we attempted to integrate the currently available data on the clinicopathological features of follicular lymphoma (FL), mantle cell lymphoma (MCL), extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT-L), and chronic lymphocytic leukemia/ small lymphocytic lymphoma (CLL/SLL) affecting these anatomical regions.

METHODS

An updated descriptive literature review was carried out and a detailed electronic search was done in multiple databases to gather all cases affecting the oral/maxillofacial region and palatine tonsils.

RESULTS

We observed that MALT-L was the most frequently reported subtype, followed by FL, MCL, and CLL/SLL. The palate was affected in a high proportion of cases and the most usual clinical presentation was an asymptomatic swelling. MALT-L and CLL/SLL neoplastic cells were strongly associated with small salivary glands. FL showed no gender preference, while MCL and CLL/SLL were more prevalent in males and MALT-L in females. Overall, cases were more common in elderly individuals. Patients' treatment and outcome varied, with MCL being the most aggressive neoplasm with a dismal prognosis in comparison to FL and MALT-L.

CONCLUSION

Despite the poor documentation in many of the cases available, especially regarding the microscopic and molecular features of tumors, this review demonstrated that the oral mature small B-cell lymphomas investigated share similar clinical presentation, but carry different prognostic significance, demanding an accurate diagnosis.

Characteristics of diffuse large B-cell lymphoma in patients with primary Sjögren's syndrome

Aim

Patients with primary Sjögren's syndrome (pSS) have an increased risk of developing diffuse large B‐cell lymphoma (DLBCL), which is an aggressive and heterogeneous non‐Hodgkin lymphoma. This study aimed to characterize DLBCLs in patients with pSS.

Method

We identified 18 patients with DLBCL and pSS over a 22‐year period. Based on the 2016 WHO guidelines, we characterized DLBCL based on immunohistochemical tests using a broad panel of antibodies, and an Epstein‐Barr virus (EBV) test using in situ hybridization.

Results

The median time from initial pSS symptom onset to the DLBCL diagnosis was 20.5 years and the median time from the pSS diagnosis until the DLBCL diagnosis was 14 years. After the lymphoma diagnosis, the median overall survival was 3 months (range: 0‐212 months) and the 5‐year overall survival rate was 37.5%. Thirteen DLBCLs were re‐classified as DLBCL, not otherwise specified (NOS) in nine cases; EBV‐positive DLBCL, NOS in two cases; and T‐cell/histiocyte‐rich large B‐cell lymphoma in two cases. Five cases of DLBCLs were not re‐classified because their EBV status was unknown. The Hans algorithm, which uses a combination of staining for CD10, BCL6, and MUM1, was used to classify the DLBCLs into the germinal center B‐cell (GCB) subtype for three cases and the non‐GCB subtype for nine cases.

Conclusion

These results indicate that DLBCL tends to occur late in pSS cases and is mainly related to the non‐GCB subtype of DLBCL.

Clonal relationship of marginal zone lymphoma and diffuse large B-cell lymphoma in Sjogren's syndrome patients: case series study and review of the literature

The occurrence of diffuse large B-cell lymphoma (DLBCL) in the course of Sjogren's syndrome (SS) is considered to be equally related either to the development of DLBCL de novo or to the transformation from marginal zone lymphoma (MZL). However, the question of possible clonal relationship between MZL and DLBCL in the group of SS patients remains open. Here we present the data concerning 194 patients with lymphoma complicated SS followed up at Nasonova Research Institute of Rheumatology during the last 22 years. Molecular analysis of tumor cells was performed for 6 SS patients who had developed both MZL and DLBCL. To assess clonal relationship between each of the tumor pairs immunoglobulin heavy chain (IGH) gene rearrangements were identified according BIOMED-2 protocol by means of multiplex polymerase chain reaction followed by GeneScan fragment analysis. Despite different localization MZL and DLBCL were clonally related in five tumor pairs. The median time to transformation was 11 months (range 0-78 months). MZL and DLBCL were clonally related in most cases from our cohort of SS patients. No statistically significant difference in survival between patients with DLBCL transformed from MZL and patients with de novo DLBCL was found in the cohort of SS patients investigated.

MALT lymphoma in labial salivary gland biopsy from Sjögren syndrome: importance of follow-up in early detection

Mucosa-associated lymphoid tissue (MALT) lymphomas are known to occur in Sjögren syndrome (SS) patients, but reported cases in labial salivary glands (LSG) are rare. We report a case of 60-year-old female patient with SS who developed MALT lymphoma in the labial salivary glands during a 2-year time interval when she was participating in the Sjögren's International Clinical Collaborative Alliance, an ongoing longitudinal multisite observational study funded by the National Institutes of Health of the United States. At follow-up exam, LSG biopsy showed atypical diffuse infiltration by mononuclear cells of variable size and atypical nuclei affecting the whole specimen with destruction of glandular architecture, leading to a diagnosis of B-cell MALT lymphoma. Computerized tomography and bone marrow biopsy failed to show additional evidence of disease. Clinical, serologic, ocular, histologic and immunohistochemical findings are presented. A "watch and wait" policy was adopted with regular examinations.

Trends and distribution of oral and pharyngeal lymphoma in Israel

OBJECTIVES

To describe the distribution and trends of oral and pharyngeal lymphoma cases in Israel.

METHODS

Incidence rates were derived from the Israel National Cancer Registry and included all registered data from 1970 to 2006. Oral lymphoma included the tongue, mouth, salivary glands, tonsils, and pharynx. Morphological description was according to WHO classification of lymphoid neoplasms.

RESULTS

A total of 670 cases were diagnosed, mean age 59.5 years, half were over 65 years old. Tonsils were the most prevalent site of involvement (36.0%), followed by the pharyngeal region and salivary glands. Over the years, the prevalence of lymphoma in salivary glands increased by 49%, whereas in tonsils lymphoma decreased by 28.6%. The overall 5-year survival rate was 57% with best rates among young people.

CONCLUSION

The correlation of survival, type of lymphoma and age, was similar to extra-oral lymphoma. A trend of increased cases in the parotid region, dissimilar to other oral sites, raises a question of possible external factors or an increase in autoimmune diseases. Head and neck clinicians should be aware of different sites, types, and prognoses for the different age groups.

Oral mucosal MALT lymphoma clinically simulating oral facial granulomatosis

Mucosal associated lymphoid tissue (MALT) lymphoma may have specific clinical associations and molecular aberrations depending on its site of origin. We present a case of oral mucosal MALT lymphoma with clinical features simulating oral-facial granulomatosis. Dermatologists are frequently called upon for the diagnosis and treatment of mucosal lesions. Increased awareness and familiarity with oral mucosal MALT lymphoma and its clinical associations are of significant importance for optimal management of this condition.

Mucosa-associated lymphoid tissue lymphoma presented as diffuse swelling of the parotid gland

Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct subtype of lymphoma. Parotid MALT lymphoma is a rare tumor that is hard to diagnose by fine-needle aspiration cytology. Therefore, partial parotidectomy is often required for a pathological diagnosis. We report a case of MALT lymphoma presented as unilateral diffuse swelling of the parotid gland, who was diagnosed by partial parotidectomy and underwent radiotherapy.

Primary salivary gland lymphoma: a clinicopathologic study of 23 cases in Taiwan

Twenty-three patients with primary salivary gland lymphoma were diagnosed between 1990 and 2001. The sites of involvement were the parotid gland in 13, the submandibular gland in 9 and the minor salivary gland in 1. The sites of lymphoma involvement beyond the salivary glands were the cervical lymph nodes in 7, bone marrow in 3, the axillary lymph nodes in 3, the nasopharynx in 2, the abdominal lymph nodes in 2, the palate, the subconjunctiva, and the spleen in 1 each patient. Histologically, 19 patients had lymphomas of mucosa-associated lymphoid tissue (MALT) with myoepithelial sialadenitis in 13, 3 patients had diffuse large cell lymphomas and 1 had follicular lymphoma. Six patients were in stage I, 4 in II, 1 in III and 12 in IV. Eight of 23 patients (35%) had autoimmune diseases before or after the diagnosis of NHL and all suffered from MALT lymphoma. Four patients with parotid MALT lymphoma had primary or secondary Sjogren's syndrome. One each patient suffered from hyperthyroidism, systemic lupus erythematosus, membranoproliferative glomerulonephritis and cryoglobulinemia, respectively. All the 6 stage I patients had achieved complete remission (CR) without relapses 17-84 months (median 44 months) after treatment. Excluding a stage IV patient with follicular lymphoma who died at 3.5 months without treatment, CR was achieved in all of the remaining 16 patients. However, a high relapse rate (9/16, 56%) was noted in stage II-IV patients. These patients tended to relapse in the original sites, but achieved CR again after chemotherapy or radiotherapy. One patient with MALT lymphoma developed histologic transformation into diffuse large lymphoma during relapse and died of refractory disease. Overall, only 2 patients succumbed. The overall survival and relapse-free survival rates at 5 years were 94.7 and 51.4%, respectively. Thus, salivary gland lymphoma proved to be an indolent disease.

MALT lymphoma of the foreskin

Here we present the first described case of MALT lymphoma involving the foreskin. The patient presented with a lump proximal to the glans penis. It was treated with radical excision and histology revealed positive margins. No further therapy was given as this may have resulted in significant morbidity. The patient remains relapse free more than 2 years later. MALT lymphomas are the third most common non-Hodgkin lymphoma accounting for 8% of cases. They have been described at almost all extranodal sites but this case is the first involving the foreskin.

Mucosa-associated lymphoid tissue lymphoma (MALT) of salivary glands and scleroderma: a case report

The connection between scleroderma and lymphoma is uncommon and its pathogenic relationship is a much debated subject. We describe the case of a patient with mucosa-associated lymphoid tissue lymphoma (MALT) of both parotid glands without clinical signs of Sjögren's syndrome who simultaneously developed scleroderma. Independently of the pathogenic mechanism of these two diseases, it seems very important to emphasize that scleroderma may be the first manifestation of lymphoma.

Infection of autoreactive B lymphocytes with EBV, causing chronic autoimmune diseases

I hypothesize that human chronic autoimmune diseases are based on infection of autoreactive B lymphocytes by Epstein-Barr virus (EBV), in the following proposed scenario. During primary infection, autoreactive B cells are infected by EBV, proliferate and become latently infected memory B cells, which are resistant to the apoptosis that occurs during normal B-cell homeostasis because they express virus-encoded anti-apoptotic molecules. Genetic susceptibility to the effects of B-cell infection by EBV leads to an increased number of latently infected autoreactive memory B cells, which lodge in organs where their target antigen is expressed, and act there as antigen-presenting cells. When CD4(+) T cells that recognize antigens within the target organ are activated in lymphoid organs by cross-reactivity with infectious agents, they migrate to the target organ but fail to undergo activation-induced apoptosis because they receive a co-stimulatory survival signal from the infected B cells. The autoreactive T cells proliferate and produce cytokines, which recruit other inflammatory cells, with resultant target organ damage and chronic autoimmune disease.

Involvement of the thyroid and the salivary glands in childhood non-Hodgkin's lymphomas at initial diagnosis

OBJECTIVE

The clinical spectrum of childhood non-Hodgkin's lymphoma (NHL) is different from that in adults, with frequent extranodal involvement. We searched the incidence and radiological appearance of the secondary involvement of the thyroid and salivary glands by ultrasonography (US) to assess its importance for staging of the disease.

MATERIALS AND METHODS

We examined the thyroid, parotid and submandibulary glands of 43 children with NHL, age ranging between 9 months and 17 years, by US.

RESULTS

According to US findings, involvement of the parotid gland was very common as detected in 18 of the cases with NHL (41%). It was the most common organ involved in lymphoma. Lymphomatous infiltration of the thyroid gland, with bilateral multiple focal lesions, was detected in two patients and proved by fine needle aspiration biopsy in all cases (5%). Salivary gland and thyroid involvement changed staging in three (6%) of the patients, however, the treatment plan was unchanged.

CONCLUSIONS

This study shows that anatomic sites, known to be very rarely involved at the initial presentation of the disease is actually more commonly involved in childhood NHL. However, it does not cause any significant change in the treatment planning or in the survival.