Primary mucosa-associated lymphoid tissue lymphoma of the salivary glands: a multicenter Rare Cancer Network study

Risk factors analysis and establishment of predictive nomogram of extranodal B-cell lymphoma of mucosal-associated lymphoid tissue

PURPOSE

The role of radiation therapy in mucosa-associated lymphoid tissue (MALT) lymphoma is poorly defined. The objective of this study was to explore the factors associated with the performance of radiotherapy and to assess its prognostic impact in patients with MALT lymphoma.

PATIENTS AND METHODS

Patients with MALT lymphoma diagnosed between 1992 and 2017 were identified in the US Surveillance, Epidemiology, and End Results database (SEER). Factors associated with the delivery of radiotherapy were assessed by chi-square test. Overall survival (OS) and lymphoma-specific survival (LSS) were compared between patients with and without radiotherapy, using Cox proportional hazard regression models, in patients with early stage as well as those with advanced stage.

RESULTS

Of the 10,344 patients identified with a diagnosis of MALT lymphoma, 33.6% had received radiotherapy; this rate was 38.9% for stage I/II patients and 12.0% for stage III/IV patients, respectively. Older patients and those who already received primary surgery or chemotherapy had a significantly lower rate of receiving radiotherapy, regardless of lymphoma stage. After univariate and multivariate analysis, radiotherapy was associated with improved OS and LSS in patients with stage I/II (HR=0.71 [0.65-0.78]) and (HR=0.66 [0.59-0.74]), respectively, but not in patients with stage III/IV (HR=1.01 [0.80-1.26]) and (HR=0.93 [0.67-1.29]). The nomogram built from the significant prognostic factors associated with overall survival of stage I/II patients had a good concordance (C-index=0.749±0.002).

CONCLUSION

This cohort study shows that radiotherapy is significantly associated with a better prognosis in patients with early but not advanced MALT lymphoma. Prospective studies are needed to confirm the prognostic impact of radiotherapy in patients with MALT lymphoma.

Frequency and malignancy rate of incidental focal salivary gland lesions identified by 18F-fluorodeoxyglucose-positron emission tomography

PURPOSE

We aimed to evaluate the frequency and malignancy rate of incidental salivary gland lesions (ISGLs) in patients undergoing 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT).

METHODS

Using a predefined algorithm, all descriptions of FDG-PET/CT scans performed in the North Denmark Region at the Department of Nuclear Medicine, Aalborg University Hospital from 1.12 2009 to 31.12 2019 were electronically searched for focal uptake in one or more salivary glands.

RESULTS

In total, 28,362 FDG-PET/CT scans were performed in the study period. ISGLs were found in 197 (0.7%). A total of 193 (98%) had parotid gland ISGL, and four (2%) had submandibular ISGL. No sublingual lesions were found. Ultimately, 117 patients (60%) were referred to the Department of Otorhinolaryngology-Head and Neck Surgery for evaluation. Fine needle aspiration biopsy was performed in 97 patients, and the most frequent cytopathology was Warthin's tumour (n = 62). Two patients had verified malignancy: one with histopathologically proven acinic cell carcinoma and one with cytopathologically proven metastasis from an oral squamous cell carcinoma.

CONCLUSIONS

Incidental salivary gland findings on FDG-PET/CT are rare, and the risk of malignancy is low. Patients with ISGL may be evaluated secondary to the primary disease, but special attention should be given to patients with prior or known head-and-neck malignancies and patients with symptoms from the salivary glands, including swelling.

MALT lymphoma of the sublingual gland: A case report with current overview of diagnostic and therapeutic strategies

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is a low-grade B-cell lymphoma. MALT lymphomas involving the sublingual gland are extremely rare. Herein, we report a case of MALT lymphoma of the sublingual gland. Additionally, we discuss challenging diagnostic aspects as well as current treatment strategies.

Influence of age on long-term net survival benefit for early-stage MALT lymphomas treated with radiotherapy: A SEER database analysis (2000-2015)

BACKGROUND

Given the lower incidence of lymphoma-related death but higher background mortality in patients with early-stage mucosa-associated lymphoid tissue (MALT) lymphoma, it is critically important to examine how age affects a treatment's survival benefit.

METHODS

9,467 patients with early-stage MALT lymphoma in the Surveillance, Epidemiology, and End Results (SEER) database treated between 2000-2015 were extracted and analyzed. Primary therapy was classified as radiotherapy (n = 3,407), chemotherapy (n = 1,294), and other/unknown treatments including observation (n = 4,766). Inverse probability of treatment weighting (IPTW) was conducted to balance baseline characteristics between groups. Relative survival (RS), standardized mortality ratio (SMR), and transformed Cox regression were conducted to compare survival differences between treatment modalities by controlling for the background mortality. Radiotherapy-age interaction was examined.

RESULTS

Across age-groups, early-stage MALT lymphoma patients were at lower risk of lymphoma-related death than death due to other causes. The 10-year overall survival (OS, 73.8%) and RS (96.6%) rates were significantly higher, and the SMR (1.14) significantly lower, with radiotherapy than with chemotherapy (OS, 61.7%; RS, 86.4%; SMR, 1.54; P < 0.001) or other/unknown treatments (OS, 61.1%; RS, 87.2%; SMR, 1.41; P < 0.001). By multivariable analysis and IPTW, radiotherapy remained an independent predictor of better RS (HR 0.81, 95%CI, 0.73-0.89; P < 0.001). A significant interaction between age and radiotherapy was identified for both RS (P_interaction = 0.016) and OS (P_interaction = 0.024), indicating greater benefit in young adults.

CONCLUSION

Radiotherapy was associated with significant better survival in early-stage MALT lymphoma, especially in young adults.

Oral manifestations of extranodal lymphomas - a review of the literature with emphasis on clinical implications for the practicing dentist

OBJECTIVE

Lymphoma is a heterogenous group of malignant tumours with proliferation of lymphoid cells or their precursors. Lymphomas in the head and neck region are usually found in Waldeyer's ring. Intraoral lymphomas are rare and the clinical presentation and roentgenological appearance may resemble other and benign conditions, entailing a risk for diagnostic delay. The objective of the present literature review was to identify subjective symptoms, clinical presentations and roentgenological appearances which should raise suspicion of lymphoma.

MATERIALS AND METHODS

The literature review identified 41 case series with head and neck lymphomas (n = 3880) and 384 case reports (n = 567 cases) of intraoral lymphomas. Information of demographics, clinical presentation, subjective symptoms and roentgenological appearance was registered.

RESULTS

The most common clinical presentation was a broad-based swelling or bulging mass with or without simultaneous ulceration, frequently with a relatively rapid growth pattern. Subjective symptoms varied considerably. Intraosseous lymphomas were frequently associated with paresthaesia or numbness. The most common roentgenological finding was a radiolucency with diffuse demarcation.

CONCLUSIONS

The clinical presentation, symptomatology and roentgenological appearance of intraoral lymphomas varied. Diagnostic delay was usually associated with a lymphoma initially misdiagnosed as a lesion of dental aetiology or a reactive lesion. Inadequate healing after tooth extraction or symptoms of numbness or pain without obvious dental origin should merit further clinical and roentgenological examination. Biopsy is indicated when there is the slightest doubt of the true nature of mucosal lesion.

Clinicopathological aspects of primary mucosa-associated lymphoid tissue lymphoma of the salivary gland: A retrospective single-center analysis of 72 cases

BACKGROUND

Salivary gland extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue lymphoma (MALT lymphoma) is uncommon and has not been studied extensively. We aimed to investigate the features of clinicopathological and molecular changes of salivary MALT lymphoma.

METHODS

Seventy-two cases of primary salivary MALT lymphoma that had clinicopathological information available were utilized in this study. MALT1 gene translocation, trisomy 3, and trisomy 18 were detected by interphase fluorescence in situ hybridization (FISH). The data were analyzed using SPSS 17.0 software package.

RESULTS

The ratio of male to female was 1:2.8, and the median age was 57.0 years. 12.5% (9/72) of the patients presented with multiple swellings. Among the others with solitary mass, the parotid gland was involved most frequently (47/63,74.6%), followed by the palate (7/63, 11.1%). 34.7% of patients had an autoimmune disease, with Sjögren syndrome (SS) being the most common. Among the 70 cases successfully performed, it was identified that trisomy 3 was the most frequent molecular change (41/70, 58.6%), followed by trisomy 18 (7/70, 10%) and MALT1 translocation (5/70, 7.1%). The tumor tissue tended to exhibit trisomy 3 in patients without SS (p = 0.038). The 5-year overall survival was 94.1%, and the 5-year disease-free survival was 85.3% (mean follow-up time: 104.7 months). The patients without SS and trisomy 18 had a prolonged recurrence-free survival (p = 0.015, p = 0.001 respectively).

CONCLUSION

Salivary gland MALT lymphoma is associated with autoimmune diseases, and trisomy 3 is the most common genetic change. Trisomy 18 can be used to predict the possibility of tumor relapse.

Marginal Cell Lymphoma Presenting as a Primary Submandibular Tumor

Primary lymphomas of the salivary glands are rare tumors seen in the head and neck. We report the case of a 52-year-old woman with an extranodal marginal cell lymphoma of her submandibular gland, whose primary presenting symptom was a slow swelling of her neck. Fine-needle aspiration of the mass was performed, followed by CT imaging studies, and both tests showed inconclusive results. The tumor was excised and the patient has been monitored with no recurrence to date. This case adds to the diverse differential diagnoses of primary tumors in the head and neck, as early consideration, identification, and management of this etiology is essential for the clinician to ensure the best patient outcomes.

Relevance on the diagnosis of malignant lymphoma of the salivary gland

Malignant lymphoma originates from the lymphohematopoietic system. It can occur in any lymphoid tissue. Malignant lymphoma of the salivary gland is rare, but its incidence has increased in recent years. Its clinical- presentations are non-specific, and it is often manifested as a painless mass in a salivary gland, which can be accompanied by multiple swollen cervical lymph nodes. Confirmation of the diagnosis before an invasive procedure is difficult. Clinically, malignant lymphoma of the salivary gland tends to be misdiagnosed, leading to an inappropriate treatment plan and the ultimate delay in the optimal treatment of the disease. This article reviews the pathogenesis, clinical features, imaging findings, diagnosis, treatment and prognosis of malignant lymphoma of the salivary gland.

Sjögren Syndrome in Primary Salivary Gland Lymphoma

OBJECTIVES

Sjögren syndrome (SS) is considered as a major etiologic factor for primary salivary gland lymphoma (SGL). However, the percentage of SGL that is caused by SS (and thus the real impact of SS on SGL epidemiology) is unclear. We aimed to assess the prevalence of SS in patients with SGL through a systematic review and meta-analysis.

METHODS

Electronic databases were searched for studies assessing the presence of SS in patients with SGL. Pooled prevalence of SS in SGL was calculated, with a subgroup analysis based on histotype (mucosa-associated lymphoid tissue [MALT] vs non-MALT).

RESULTS

Sixteen studies with 665 SGLs were included. Pooled prevalence of SS in SGL was 18.2%, with high heterogeneity among studies. In MALT SGL, the prevalence of SS was 29.5%, with moderate heterogeneity. In non-MALT SGL, the prevalence of SS was 0%, with null heterogeneity.

CONCLUSIONS

SS seems to be responsible for a significant but minor portion of SGLs. SS appears involved in MALT-type SGL but not in other histotypes.

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.

Oral lesion as the primary diagnosis of non-Hodgkin's lymphoma: a 20-year experience from an oral pathology service and review of the literature

PURPOSE

We aimed to investigate the frequency and clinicopathological features of oral NHL in our institution as well as to compare the data gathered from other oral pathology and general pathology services published in the literature.

METHODS

Clinical records of patients diagnosed with NHL exclusively affecting the oral cavity were reviewed from 1997 to 2017. Additionally, a review of the literature over a 20-year period was conducted aiming to examine articles on oral NHLs.

RESULTS

Oral NHLs represented 0.1% (n = 98) of the total number of biopsies (68,229) received during the period evaluated (1997-2017). The mean age at the diagnosis was 47 years. Most patients were white (67.3%). A nodular lesion was the most frequent presentation (54.9%) and pain was described in 47.1% of the cases. The most common diagnosis was diffuse large B cell lymphoma (42%) followed by plasmablastic lymphoma (24%). Only 19 articles were included in the review of the literature.

CONCLUSIONS

Although NHLs are rare in the oral cavity, clinicians and surgeons have an important role in promptly diagnosing lymphomatous lesions to refer the patient to a proper treatment.

Cancers of the Major Salivary Gland

Salivary gland malignancies are rare tumors that comprise multiple histologic entities with diverse clinical behavior. Mucoepidermoid carcinoma is the most frequent primary salivary malignancy, followed by adenoid cystic and acinic cell carcinoma. Although most salivary malignancies are asymptomatic, presentation with a rapidly enlarging mass may be accompanied by pain, functional neurologic deficits, soft-tissue invasion, or nodal enlargement. Assessment of clinical behavior and physical exam greatly contributes to diagnostic workup. Preoperative imaging, to include ultrasound, computed tomography, or magnetic resonance imaging, may assist with surgical planning. Limitations of preoperative fine-needle aspiration cytology mean that, in some cases, definitive histologic diagnosis may not be established until therapeutic surgery is undertaken. Treatment strategies rely on oncologic resection of the primary site with negative margins as well as adjuvant radiotherapy in patients with high-risk features, such as high-grade histology, advanced T class, or perineural invasion. Regional lymphadenectomy is recommended for involved nodal basins. Patients with clinically node-negative disease at high risk for occult nodal metastases may be considered for elective lymphadenectomy or radiotherapy. Use of chemotherapy in the adjuvant setting, in combination with radiotherapy, remains controversial. The rate of objective response to palliative chemotherapy in recurrent or metastatic salivary gland malignancy remains low. In studies that include a significant proportion of adenoid cystic carcinomas, whether disease stability represents an indolent disease process or the true effect of a therapeutic drug may be difficult to discern. Recognition of genetic alterations and protein expression unique to salivary malignancies presents exciting new opportunities for molecularly targeted therapy, although the response to molecularly targeted therapy in studies has been modest thus far.

Lymphomas of the head and neck region: an update

The field of haematopathology is rapidly evolving and for the non-specialized pathologist receiving a specimen with the possibility of a lymphoid malignancy may be a daunting experience. The coincidence of the publication, in 2017, of the WHO monographies on head and neck and haematopoietic and lymphoid tumours prompted us to write this review. Although not substantially different from lymphomas elsewhere, lymphomas presenting in this region pose some specific problems and these are central to the review. In addition, differences in subtype frequency and morphological variations within the same entity are discussed. The difficulty in diagnosis related to some specimens led us to briefly mention common subtypes of systemic lymphomas presenting in the head and neck region.

18F-FDG PET/CT for staging and response assessment of primary parotid MALT lymphoma with multiple sites involvement: A case report

RATIONALE

Mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal low-grade B cell lymphoma that generally exhibits an indolent clinical course. Currently, the application of F-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) in MALT lymphoma is still controversial. Herein, we reported a case of using F-FDG PET/CT for staging and response assessment of primary parotid MALT lymphoma with multiple sites involvement. As far as we know, there are no similar case reports have been published before.

PATIENT CONCERNS

A 71-year-old woman, who received mass resection twice during the past 2 years due to the repeatedly relapse of facial painless masses and diagnosed as reactive lymphoid hyperplasia by pathologic tests. However, the pathological diagnosis was then changed to primary parotid MALT lymphoma after left parotidectomy operation because of a new mass found in her left parotid. Four months later, the right eyelid of the patient swelled with a blurred vision. Then, F-FDG PET/CT scan was performed for staging, and the imaging results showed an abnormal increase of F-FDG uptake in multiple sites including bilateral ocular adnexal, lungs, pleura, occipital subcutaneous tissue, left kidney, and lymph nodes.

DIAGNOSES

The patient was diagnosed as primary parotid MALT lymphoma with Ann Arbor stage of IVA based on the F-FDG PET/CT findings.

INTERVENTIONS

The patient received 4 cycles of chemotherapy, followed by a partial metabolic remission (PMR), which was determined by interim F-FDG PET/CT, and finally additional 2 cycles of chemotherapy.

OUTCOMES

The follow-up study illustrated that the patient had been alive and doing well at 12 months after chemotherapy.

LESSONS

Although MALT lymphoma normally localizes in the primary organs, the involvement of multiple organs and lymph nodes is possible. The use of PET/CT demonstrated significant clinical values in the accurate staging and response assessment of F-FDG-avid MALT lymphoma. It is potentially useful for indicating the progress and transformation of MALT lymphoma, and guidance in localization of pathological biopsy. It is also helpful for clinicians to choose reasonable treatment strategy and improve the prognosis of patients.

Primary extranodal lymphoma of the glands. Literature review and options for best practice in 2019

Primary extranodal non-Hodgkin's lymphomas (EN-NHL) are a heterogeneous group of malignancies that involve numerous entities with significant difference in terms of tumor site locations, prognostic factors, biology expression, and therapeutic options. In the literature, many EN-NHL types were reported from limited series which only allowed narrow views for elucidating prognostic factors and defining the role of loco-regional therapies in the era of new systemic and biologically targeted therapies. The Rare Cancer Network (RCN), an international multidisciplinary consortium, has published a number of reports on several EN-NHL sites which included many gland locations. In this review, we will focus on the recent literature for a selected number of EN-NHL types in both exocrine and endocrine gland locations. We aim to provide renewed and clear messages for the best practice in 2019 for diagnosis, histopathology, treatments, and also their prognostic implications. We believe that better understanding of molecular and genetic characteristics of these particular diseases is crucial for an appropriate management in the era of personalized treatment developments.

Evaluation of the diagnostic value of immunoglobulin clonal gene rearrangements in patients with parotid gland MALT lymphoma using BIOMED-2 protocol

OBJECTIVES

The aim of this study was to evaluate the diagnostic value of immunoglobulin (Ig) clonal gene rearrangements for mucosa-associated lymphoid tissue (MALT) lymphoma of the parotid gland.

STUDY DESIGN

We collected and retrospectively analyzed clinical data of 21 patients referred to our institution between 2009 and 2017. Eight patients had been primarily diagnosed MALT lymphoma of the parotid gland and the remaining patients with lymphoepithelial lesion. Paraffin-embedded tissues were chosen for extracting genomic DNA and multiplex primer polymerase chain reaction amplification by using BIOMED-2 primers. Polymerase chain reaction amplification products were analyzed by heteroduplex analysis.

RESULTS

Generally, 17 patients were identified to have parotid gland MALT lymphoma; 47.06% of them had Sjögren syndrome. The sensitivity of IGH VH-J_H FR1, FR2, FR3, IGK Vκ-Jκ, and IGK (Vκ-Kde and intron-Kde) as targets was 76.47%, 82.35%, 88.24%, 29.41%, and 35.29%, respectively. The sensitivity of combined application of the above-mentioned 3 IGH primers as targets was 100%. The sensitivity of combined application of the above two IGK primers as targets was 58.82%.

CONCLUSIONS

Ig clonal gene rearrangements assays using BIOMED-2 protocol can be a highly reliable diagnostic method for parotid gland MALT lymphoma. For patients with Sjögren syndrome along with histologically benign lymphoepithelial lesion, identification of Ig clonal gene rearrangements is important for routine differential diagnosis.

Radiation for MALT of the Submandibular Gland

We are reporting a case of a 27-year-old woman with a history of swelling in the left submandibular region. This swelling was associated with a mass, and this was pathologically confirmed to be an extranodal marginal zone lymphoma (MALT). The patient underwent surgical excision and postoperative adjuvant radiation therapy. The patient tolerated treatments well and remains free of disease. Here, we describe the case and management described in the current literature.

Clinical features and management of non-gastrointestinal non-ocular extranodal mucosa associated lymphoid tissue (ENMALT) marginal zone lymphomas

Extranodal mucosa associated lymphoid tissue (ENMALT) marginal zone lymphomas may arise at any site of the body. The most frequent localizations other than gastrointestinal and eye are salivary gland, skin, lung and thyroid. These lymphomas usually arise in a setting of inflammation due to a persistent infection or autoimmune diseases such as Sjogren syndrome in salivary MALT lymphomas and Hashimoto's thryroiditis in thyroid lymphomas. They affect middle-aged patients with a female predominance when lymphoma arises in certain locations. Patients often present with localised stage I or II although disseminated disease may be present at diagnosis or relapse in a third of the cases. Biopsy of the affected site is mandatory to establish the diagnosis and a full work-up staging is recommended. The clinical course is indolent and prognosis is good despite that recurrences following response to therapy are frequent. Surgery, radiotherapy and/or Rituximab based regimens are effective in these lymphomas.

Cancers of major salivary glands

Major salivary gland malignancies are a rare but histologically diverse group of entities. Establishing the diagnosis of a malignant salivary neoplasm may be challenging because of the often minimally symptomatic nature of the disease, and limitations of imaging modalities and cytology. Treatment is centered on surgical therapy and adjuvant radiation in selected scenarios. Systemic therapy with chemotherapeutic agents and monoclonal antibodies lacks evidence in support of its routine use.

Primary Sjögren's syndrome initially presenting as submandibular mucosa-associated lymphoid tissue lymphoma: A case report

The present study reports the case of a 24-year-old female affected with primary Sjögren's syndrome (pSS), who presented with mucosa-associated lymphoid tissue (MALT) lymphoma of the submandibular gland. Reports of such cases, particularly in young patients, are very rare. The patient, who presented no oral or ocular symptoms prior to the development of the mass, underwent surgical ablation of the gland, and MALT lymphoma was diagnosed by histopathology. Since MALT lymphoma in the submandibular gland is rarely observed in otherwise healthy young females, a rheumatologist and an oncologist were consulted. Following a number of immunological tests, the results of the Schirmer's and Saxon tests were negative. However, the antinuclear antibody test revealed a speckled appearance, and there was also strong positivity for the serological markers of Sjögren's syndrome. Consequently, pSS was diagnosed, despite the fact that the patient did not fulfill all the diagnostic criteria for the disease. Therefore, MALT lymphoma in a single salivary gland should be used as a differential diagnosis for Sjögren's syndrome in young asymptomatic patients. Additionally, a multidisciplinary team is required for the treatment and management of these patients.

[A Clinical Study of a Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma of Salivary Glands]

Malignant lymphoma involving the salivary glands is a rare entity that accounts for only 1 to 4% of all salivary gland tumors. We have analyzed the clinical features of MALT lymphoma of the salivary glands in 7 patients whom we have treated in the past 10 years, including data from 43 patients in the literature. The most common symptom was persistent or progressive swelling of the salivary glands without pain or facial palsy. The affected glands were the unilateral parotid in 62%, the unilateral submandibular gland in 6.8%, and the bilateral parotid or submandibular gland in 6.8%. The salivary gland swelling as evaluated by MRI or ultrasonography consisted of a localized solitary tumor in 68.9%, multiple tumors in 10.3%, and diffuse swelling of the gland in 26.1%. In 24 out of 50 patients, MALT lymphoma developed on the basis of Sjögren's syndrome. As for diagnosis, malignant lymphoma was suspected only in 4 cases out of 11 (36.7%) based on the fine needle aspiration cytology. In all patients, a definitive diagnosis was obtained based on histopathological study of the localized tumor or the biopsy specimens. When patients with Sjögren's syndrome have developed persistent swelling of the salivary glands, it is necessary to rule out malignant lymphomas, especially MALT lymphoma, by combination of ultrasonography, MRI, FNA, and biopsy or open surgery depending on image findings. The treatment of MALT lymphoma has not yet been standardized because MALT lymphoma is a rare entity. The choice of initial treatment is important because it is related to its prognosis. If MALT lymphoma remains in a local site, we should undertake an operation or radiotherapy. If MALT lymphoma has dissemineated systemically, we should choose chemotherapy.

Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue of the Salivary Glands: A Multicenter, International Experience of 248 Patients (IELSG 41)

BACKGROUND

The salivary gland is one of the most common sites involved by nongastric, extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT). A large series of patients with long-term follow-up has not been documented. This multicenter, international study sought to characterize the clinical characteristics, treatment, and natural history of salivary gland MALT lymphoma.

METHODS

Patients with biopsy-confirmed salivary gland MALT lymphoma were identified from multiple international sites. Risk factors, treatment, and long-term outcomes were evaluated.

RESULTS

A total of 247 patients were evaluated; 76% presented with limited-stage disease. There was a history of autoimmune disorder in 41%, with Sjögren disease being the most common (83%). Fifty-seven percent of patients were initially treated with local therapy with surgery, radiation, or both; 37 of patients were treated with systemic therapy initially, with 47% of those receiving rituximab; and 6% of patients were observed. The median overall survival (OS) was 18.3 years. The median progression-free survival (PFS) following primary therapy was 9.3 years. There was no difference in the outcomes between patients receiving local or systemic therapy in first-line management. On multivariate analysis, age <60 years and low to intermediate international prognostic index were associated with improved OS and PFS; Sjögren disease was associated with improved OS.

CONCLUSION

Salivary gland MALT lymphoma has an excellent prognosis regardless of initial treatment, and patients with Sjögren disease have improved survival. Risks for long-term complications must be weighed when determining initial therapy.

Modern radiation therapy for extranodal lymphomas: field and dose guidelines from the International Lymphoma Radiation Oncology Group

Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

Salivary gland lymphoproliferative disorders: a Canadian tertiary center experience

Salivary gland lymphoproliferative disorders (SGLD) are very rare tumors and clinicopathological data is sparse. In a Canadian series of 30 cases, extracted from the surgical pathology files of The Ottawa Hospital between 1990 and 2010, a clinical, histopathological, and immunophenotypic analysis was conducted. Tumors were staged using the Ann Arbor staging and classified using the World Health Organization 2008 classification. There were 15 salivary gland (SG) primary lymphomas with localized disease, predominantly mucosa associated lymphoid tissue type marginal zone lymphoma (MALT-L), but with a significant incidence of low grade follicular lymphoma (FL) and diffuse large B cell phenotype as well. There were 7 systemic SG lymphomas and 5 patients were diagnosed with lymphoproliferative disorders originating from intra-parotid lymph nodes. Finally, the remaining 3 cases represented reactive sialadenitis. A literature review was conducted and our primary lymphoma group was compared to those from other countries. SGLDs are predominantly B cell lymphomas that develop in older adults. Primary tumors, which have MALT-L and low grade FL characteristics, have a favorable survival, however MALT-L have a high rate of relapse. A minority of SG lesions are excised secondary to lymphomas that definitely arose from intra-parotid lymph nodes.

Radiotherapy in marginal zone lymphoma

Purpose

To evaluate the efficacy of radiotherapy (RT) for early-stage nodal and extranodal marginal zone lymphoma (MZL).

Materials and methods

Patients with stage I (n = 22) and stage II (n = 8) MZL, who were treated with RT were reviewed. The primary tumor localisation was in the orbita (n = 12), stomach (n = 8), head and neck other than the orbita (n = 8), breast (n = 1) and one case of marginal zone lymphoma of the skin (n = 1). The median radiotherapy dose was 40 Gy (5 to 45 Gy).

Results

The median follow-up time was 103 months. The 5-year overall survival and event-free survival rates were 85 ± 7% and 71 ± 9%, respectively. There was no infield recurrence. Recurrence occurred outside of the radiation field in six patients. The relapses were treated with salvage RT and had excellent local control (100%) at five years after salvage RT.

Conclusions

Localized extranodal MZL have an excellent prognosis following moderate-dose RT. RT is also an effective salvage therapy in cases of localized recurrence. Further clinical studies should evaluate the optimal dose for MZL.

The Rare Cancer Network: achievements from 1993 to 2012

The Rare Cancer Network (RCN), founded in 1993, performs research involving rare tumors that are not common enough to be the focus of prospective study. Over 55 studies have either been completed or are in progress.

The aim of the paper is to present an overview of the 30 studies done through the RCN to date, organized by disease site. Five studies focus on breast pathology, including sarcoma, lymphoma, phyllodes tumor, adenoid cystic carcinoma, and ductal carcinoma in situ in young women. Three studies on prostate cancer address prostatic small cell carcinoma and adenocarcinoma of young and elderly patients. Six studies on head and neck cancers include orbital and intraocular lymphoma, mucosal melanoma, pediatric nasopharyngeal carcinoma, olfactory neuroblastoma, and mucosa-associated lymphoid tissue lymphoma of the salivary glands. There were 4 central nervous system studies on patients with cerebellar glioblastoma multiforme, atypical and malignant meningioma, spinal epidural lymphoma and myxopapillary ependymoma. Outside of these disease sites, there is a wide variety of other studies on tumors ranging from uterine leiomyosarcoma to giant cell tumors of the bone. The studies done by the RCN represent a wide range of rare pathologies that were previously only studied in small series or case reports. With further growth of the RCN and collaboration between members our ability to analyze rare tumors will increase and result in better understanding of their behavior and ultimately help direct research that may improve patient outcomes.

[MALT-type parotid lymphoma--a case report and the review of the literature]

Primary lymphomas of the salivary glands are rare. It is estimated that they constitute no more than 5% of all lymphomas in different locations. The most common subtype developing in parotid glands is marginal zone B-cell mucosa associated lymphoid tissue type lymphoma (MALT) that belongs to a group of low-grade tumours. There are many factors associated with the incidence of that proliferative process: environmental and infectious agents as well as immune deficiency states. We describe a case of primary non-Hodgkin's lymphoma of the parotid gland arising in the background of previously undiagnosed and untreated Sjögren's syndrome in a 52-year-old woman. The article concerns a short review of the literature regarding etiology, symptoms, treatment and survival prognosis in that rare disease as well. MALT lymphomas should always be considered in the differential diagnosis of the tumors and swelling of the parotid gland area. A special, regular monitoring should include all patients with Sjögren's syndrome as those with the proven greater risk of developing that proliferative disease. The role of the laryngologist in the case of MALT-type lymphoma of the parotid gland should focus on a diagnosis and possible tumor cytoreduction with maximal saving of the facial nerve. The essential treatment of this pathology is one of the oncologists and haematologists.

Primary parotid gland lymphoma: a case report

INTRODUCTION

Mucosa associated lymphoid tissue lymphomas are the most common lymphomas of the salivary glands. The benign lymphoepithelial lesion is also a lymphoproliferative disease that develops in the parotid gland. In the present case report, we describe one case of benign lymphoepithelial lesion with a subsequent low transformation to grade mucosa associated lymphoid tissue lymphoma appearing as a cystic mass in the parotid gland.

CASE PRESENTATION

A 78-year-old Caucasian female smoker was referred to our clinic with a non-tender left facial swelling that had been present for approximately three years. The patient underwent resection of the left parotid gland with preservation of the left facial nerve through a preauricular incision. The pathology report was consistent with a low-grade marginal-zone B-cell non-Hodgkin lymphoma (mucosa associated lymphoid tissue lymphoma) following benign lymphoepithelial lesion of the gland.

CONCLUSIONS

Salivary gland mucosa associated lymphoid tissue lymphoma should be considered in the differential diagnosis of cystic or bilateral salivary gland lesions. Parotidectomy is recommended in order to treat the tumor and to ensure histological diagnosis for further follow-up planning. Radiotherapy and chemotherapy should be considered in association with surgery in disseminated forms or after removal.