Lymphoplasmacytoid lymphoma elaborating lambda chain paraprotein with amyloid deposition in Sjögren's syndrome

Lessons from diseases mimicking Sjögren's syndrome

Sjögren's syndrome (SS) is a systemic autoimmune disease that mainly affects the exocrine glands and usually presents as persistent dryness of the mouth and eyes because of functional impairment of the salivary and lacrimal glands. The histological hallmark is a focal lymphocytic infiltration of the exocrine glands, and the spectrum of the disease extends from an organ-specific autoimmune disease (autoimmune exocrinopathy) to a systemic process with diverse extraglandular manifestations. In the absence of an associated systemic autoimmune disease, patients with this condition are classified as having primary SS. The differential diagnosis includes processes that specifically involve the exocrine glands. On the one hand, some chronic viral infections may induce lymphocytic infiltration of the exocrine glands, in some cases indistinguishable from that observed in primary SS. On the other hand, some processes may mimic the clinical picture of SS through nonlymphocytic infiltration of the exocrine glands. This review focuses on these two groups of diseases that mimic SS (infections and infiltrating processes).

Parotid Gland Mucoepidermoid Carcinoma Associated With Myasthenia Gravis

Myasthenia gravis (MG) is an autoimmune neuromuscular disease. Although most MG cases do not have accompanying malignant disease, patients with thymoma may have an increased risk for secondary malignancy. The reason MG patients are prone to developing cancer is not very well known. Salivary gland tumors account for approximately 3% of head and neck tumors, and approximately 80% of these occur in the parotid gland. Mucoepidermoid carcinoma is the most common malignant tumor of the parotid gland. MG may be associated with squamous cell carcinoma of the head and neck. We present a patient with MG who developed parotid gland mucoepidermoid carcinoma. MG patients with parotid gland cancer have not been previously reported. We also discuss the possible mechanisms of tumor development in an MG patient.

Minor salivary gland hyalinisation and amyloidosis in low-grade lymphoma of MALT

Two patients with low-grade lymphoma of mucosa-associated lymphoid tissue (MALT) arising in primary Sjögren's syndrome developed solitary nodules in their lips. Histologically both lesions showed enlargement and hyalinisation of single minor salivary glands with acinar atrophy, loss of most ducts and conversion into almost acellular sclerotic eosinophilic masses. In one case the lesion was shown to contain an amyloid component. No amyloid was detected in the second case but deposition of collagen and basement membrane and sclerotic neoplasm were excluded.

Atypical lymphoid infiltrates arising in cutaneous lesions of connective tissue disease

Atypical lymphoid infiltrates occurring in the setting of connective-tissue disease (CTD) comprise malignant neoplasms of B-cell or T-cell phenotypes and various reactive lymphoid hyperplasias, such as myoepithelial sialadenitis, lymphocytic thyroiditis, and lymphocytic interstitial pneumonitis. We describe 17 patients with atypical lymphoid infiltrates arising in cutaneous lesions of CTD, the spectrum of which included lupus erythematosus, dermatomyositis, relapsing polychondritis, and lichen sclerosus et atrophicus. There were two principal categories, pseudolymphoma and malignant lymphoma, the former representing 15 of the 17 cases. The clinical and histologic features and possible pathogenetic mechanisms are discussed.

Primary Sjögren's syndrome (SS) and malignant lymphoma. A retrospective cohort study of 55 patients with SS

The aim of this study was to assess the prevalence of malignant lymphomas in patients with long-standing primary Sjögren's syndrome (pSS). We retrospectively studied a cohort of 55 patients with pSS over a mean follow-up period of 12 years. Five patients (9%) developed malignant lymphoma. The interval between the diagnoses of SS and lymphoma ranged from four to 12 years (mean = 6.5 years). The lymphoma arose in the lymph nodes in two cases, the parotid gland in one case, the lacrimal gland in one case, and the lung in one case. All five cases were B-cell low-grade lymphomas. Among our SS patients, those with extraglandular manifestations and/or a mixed cryoglobulin were at increased risk for lymphoma development. Secondary lymphoma carried a poor prognosis in our study. Three of the six SS patients who died during the follow-up period had lymphoma.

Primary salivary gland amyloidosis causing sicca syndrome

Sicca syndrome (SS), consisting of xerostomia and xerophthalmia, may be caused by various disease processes. We present a unique case of SS secondary to primary amyloidosis. Amyloidosis is a rare but definite cause of SS and should be included in the differential diagnosis of any patient who presents with sicca symptoms. A literature review comparing amyloidotic patients with SS and patients with amyloidosis only demonstrates that both of these groups of patients present similarly with regard to symptoms. However, the majority of patients with SS present with sicca symptoms initially in addition to symptoms of amyloidosis. These SS patients also present with proteinuria and negative serology test results. Therefore, patients presenting with sicca symptoms, proteinuria, and negative serologic findings should be suspect for amyloidosis. The importance of distinguishing the diagnosis of Sjögren's syndrome from SS in these patients cannot be overemphasized. There is a significantly higher incidence of developing a lymphoma in Sjögren's syndrome patients. This has important implications for the head and neck surgeon treating these patients.