The Clinical Presentation of Non-Hodgkin Lymphomas of the Major Salivary Glands

Current evidence on diagnosis and treatment of parotid gland lymphomas: a systematic review

BACKGROUND AND PURPOSE

Parotid gland lymphoma (PGL) is a rare and challenging diagnosis. Different lymphomas can develop in the parotid gland, with the most common being the mucosa-associated lymphoid tissue (MALT) lymphoma, which originates directly from the glandular parenchyma. Other histologic subtypes arise from both intraglandular and extraglandular parotid lymph nodes. A consensus on diagnosis and treatment of PGL is still lacking, and published data is scarce and heterogeneous.

METHODS

We performed a systematic review of the literature, including studies published after 2001, when the WHO classification of lymphoid tumours was introduced.

RESULTS

Twenty retrospective studies were included in the analyses, eight of which focused exclusively on MALT lymphomas. Final analysis included 612 cases of PGL, with a 1.68:1 F/M ratio. MALT lymphoma was the most common histology, followed by follicular and diffuse large B-cell lymphoma. Most cases were low stages (IE/IIE acc. Ann Arbour, 76.5%) and only 10% of patients presented with symptoms, most commonly pain (4.8%) and B symptoms (2.2%). A high prevalence of associated autoimmune diseases was found, particularly Sjögren's syndrome, that affected up to 70% of patients with MALT lymphoma. In most cases diagnosis was achieved through parotidectomy (57.5%), or open biopsy (31.2%). Treatment strategies were either surgical, non-surgical or a combination of modalities. Surgery as a single-modality treatment was reported in about 20% of patients, supposing it might be a valuable option for selected patients.

CONCLUSIONS

Our review showed that the diagnosis and treatment of PGLs is far from being standardized and needs further, more homogeneous reports to reach consensus.

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.

Treatment of Parotid Non-Hodgkin Lymphoma: A Meta-Analysis

Purpose

This meta-analysis aimed to review the published outcomes of parotid non-Hodgkin lymphoma (NHL) pertaining to different treatment modalities.

Materials and Methods

A total of 48 journal articles published between 1993 and 2015, comprising 742 cases of parotid NHL, were initially evaluated. In total, 108 patients from 12 studies who had sufficient data for analysis, including age, tumor histopathology, treatment modality, and outcome at final follow-up, were included. Patients were randomly assigned to different categories on the basis of histopathology and treatment modality. Groups were compared using Kaplan-Meier survival curve analysis and the Mann-Whitney U test.

Results

Log-rank tests demonstrated that for early-stage (I and II) parotid NHL of all histopathology variants, radiation therapy significantly improved the survival rate versus chemotherapy (P = .043), as well as combined treatment with chemotherapy and radiation therapy (P = .023). For early-stage diffuse large B-cell lymphoma, combined treatment significantly improved survival versus single treatment (P = .028). No treatment was received by seven patients with early-stage mucosa-associated lymphoid tissue lymphoma after undergoing parotidectomy. When the clinical outcomes of these patients were compared with those of other patients with the same histology who underwent further treatment, no significant differences were noted in survival outcomes.

Conclusion

Radiation therapy seems to be a valid treatment of early-stage parotid NHL. However, for diffuse large B-cell lymphoma, survival was higher with combined treatment versus single treatment. For early-stage parotid mucosa-associated lymphoid tissue lymphoma, complete excision of the tumor through superficial parotidectomy may have similar survival outcome.

Non-Hodgkin lymphoma involving the parotid gland: CT and MR imaging findings

OBJECTIVES

As an uncommon neoplasm, parotid non-Hodgkin lymphoma (NHL) comprises mucosa-associated lymphoid tissue (MALT) and non-MALT lymphomas. Both types of lymphoma vary in prognosis and treatment. The aim of this study was to explore CT and MRI characteristics of these two types of lymphoma.

METHODS

61 cases of parotid NHL, 34 MALT and 27 non-MALT lymphomas with histopathological confirmation were examined with routine CT and MR scans prior to treatment, and retrospectively reviewed.

RESULTS

On CT and MRI, 34 MALT lymphomas presented with 11 solid and 23 solid-cystic forms, whereas 27 non-MALT lymphomas presented with 25 solid and 2 solid-cystic forms (p < 0.01).

CONCLUSIONS

Parotid MALT lymphoma is characterized mainly by the solid-cystic form, whereas non-MALT lymphoma is characterized mainly by the solid form. The differences on CT and MRI can offer helpful information for differentiation of both types of parotid NHL.

Follicular lymphoma frequently originates in the salivary gland

The aim of the present study was to examine the clinicopathological presentations of follicular lymphomas (FL) of the salivary glands, as compared to mucosa-associated lymphoid tissue (MALT) lymphomas. A total of 27 primary salivary gland lymphomas were examined: 6 FL (five, grade 1; one, grade 2); 19 MALT lymphomas; and two diffuse large B-cell lymphomas. The FL patients ranged in age from 24 to 73 years, with a mean of 49 years, which was younger than that of MALT patients (mean: 64 years; P < 0.05). Four of the six FL arose from the submandibular gland, which was the origin of only five out of a total of 19 MALT lymphomas. One FL patient was in clinical stage (CS) IE, two in CS IIE, and two in CS III and IV. As regards the MALT lymphoma patients, 13 (68%) were in CS IE and five (26%) in CS IIE. None of the FL patients had clinical diagnosis of autoimmune disease but eight MALT lymphoma patients had autoimmune disease. The present study found a relatively high incidence of FL in the salivary glands. The observed differences in age of onset, background of autoimmune disease, and lesion site suggests that the pathogenesis of FL may differ from that of MALT lymphoma.