Primary parotid gland lymphoma: a case report

Head and neck follicular lymphoma with marginal zone differentiation and BCL2 translocation t(14;18) in both nodular and extranodular sites: a case report with mini-review

OBJECTIVE

Head and neck follicular lymphoma (FL) with marginal zone (MZ) differentiation is a rare high-risk B-cell composite variant that has been reported in nodular but not extranodular sites in the parotid glands. Here we summarize the literature on FL with MZ differentiation in head and neck nodular sites and describe a rare case of extranodular FL with MZ differentiation in the parotid gland.

STUDY DESIGN

We examined both the germinal center and MZ components of the parotid and bone-marrow biopsies of a 65-year-old female histologically, immunohistochemically, and molecularly to identify B-cell, germinal center, and follicular dendritic cell markers.

RESULTS

The immunohistochemical and molecular analysis provided evidence that the FL and the MZ components derived from the same B-cell clone with a similar BCL2/IGH t(14;18) translocation site. The differentiated cells in the MZ did not express germinal center markers BCL6 and CD10. Both the parotid and bone-marrow proliferative B cells showed BCL6, CD2O, and CD79a positivity.

CONCLUSIONS

Head and neck FL with MZ differentiation can develop in both nodular and extranodular sites and is characterized by BCL2 translocation t(14;18). Although the mechanism of MZ differentiation is unclear, the characterization of this rare histopathologic phenomenon might be clinically important.

Linfoma no Hodgkin tipo MALT de la glándula parótida

Lymphomas of the salivary glands are a rare entity with a rare incidence. They are more commonly found on the parotid gland, followed by the submandibular and sublingual glands. The majority of parotid lymphomas are non-Hodgkin’s lymphomas and are considered to be derived from mucosal-associated lymphoid tissue (MALT). Reports of these cases are scarce and often misdiagnosed since: their manifestation is relatively benign, they have a localized behavior, a slow growth and the evolution takes several years. Key words: Type MALT lymphoma; parotid gland tumor

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.

An Algorithm Approach to Diagnosing Bilateral Parotid Enlargement

Objective

This contemporary review aims to categorize the disease entities that cause bilateral parotid enlargement and to develop a question-based algorithm to improve diagnosis of bilateral parotid masses.

Data Sources

A PubMed search for bilateral and parotid showed 818 results. Of these, 68 relevant studies were reviewed to compile a list of disease processes that can cause bilateral parotid enlargement.

Review Methods

A total of 22 diseases entities were reviewed. The disease processes were initially grouped into 6 categories based on etiology: sialadenosis, infection, neoplasm, autoimmune, iatrogenic, and miscellaneous. For each lesion, the incidence, history, and physical examination were compiled in a matrix.

Conclusion

After reviewing the matrix, it was clear that grouping diseases based on specific history and physical findings limits the differential diagnosis. The most important factors included disease incidence, timing of onset, nodular or diffuse, pain, and overlying skin changes. With this algorithm, the differential diagnosis can be limited from 28 to 7 or fewer likely diagnoses for a given presentation.

Implications for Practice

Bilateral parotid disease has a wide differential diagnosis with an expanding number of available tests. An algorithm, based solely on data obtained from the history and physical examination in the first patient encounter, may reduce the differential and aid the clinician in deciding on further workup and treatment. Following the algorithm presented here should allow the clinician to arrive at a diagnosis rapidly without ordering unnecessary tests and wasting resources.

Isolated B-cell non-Hodgkin's lymphoma of the parotid gland presenting as an ulcerating facial mass and sepsis during an acute medical take

Lymphoma presenting as a parotid gland tumour without systemic involvement is rare, especially with respect to a non-Hodgkin's lymphoma. Furthermore, when such cases present there is often a low degree of clinical suspicion as there may be few clinical features to suggest the diagnosis. We describe an unexpected case that presented during an acute medical intake. The case was an 84-year-old man presenting acutely unwell with an ulcerating mass over the right side of the face, septicaemia and acute kidney injury. Following aggressive initial management the patient improved. Later cytological examination of a fine needle aspiration from the mass confirmed a B-cell non-Hodgkin's lymphoma. He had no evidence of other systemic involvement or of B-symptoms. We report on the case and briefly review the available literature relating to the prevalence of non-Hodgkin's lymphoma of the parotid gland.