Peripheral T-Cell Lymphoma of the Submandibular Salivary Gland as an Unusual Manifestation of Richter’s Syndrome: A Case Report and Literature Review

Abstract

Richter's syndrome is the development of high-grade non-Hodgkin lymphoma (NHL) or Hodgkin lymphoma in patients with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). In most patients with Richter's syndrome, the high-grade NHL is diffuse large B-cell lymphoma. Only a small minority of CLL/SLL patients develop T-cell malignancies. Herein, we describe a 40-year-old male patient presenting with peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) in the submandibular salivary gland, two years after the diagnosis of CLL/SLL. The PTCL-NOS consisted of small lymphocytes, which complicated diagnosis. Immunohistochemical, cytological, and molecular studies allowed the correct diagnosis of composite lymphoma (SLL/PTCL-NOS) of the submandibular salivary gland. The PTCL-NOS had a cytotoxic phenotype and aberrant expression of CD79a. There was no evidence to suggest that the PTCL-NOS of the submandibular salivary gland developed from an intimately associated submandibular lymph node or by PTCL-NOS dissemination. A review of the literature and presented case suppose that the PTCLs developed following CLL/SLL have the cytotoxic phenotype and can clinically mimic typical Richter's syndrome.

Follicular Lymphoma Mimicking a Benign Submandibular Gland Tumor

“…As previously mentioned, lymphomas of the salivary glands may include extra-nodal and nodal-type lymphomas. Differentiating the both types can be difficult because lymphoma cells often spill over into the adjacent tissues [17]. Cervical lymphadenopathy is the most frequent head and neck presentation in nodal type NHL.…”

“…It could develoved from B-cells, T-cells, and NK cells [7,19]. Typically, NHL in the neck are from mature B cells origin [10,17]. The most common type is diffuse large B-cell lymphoma (30% of all malignancies) followed by follicular lymphoma, marginal nodal zone B-cell lymphoma, Mantle cell lymphoma, extra-nodal marginal zone B-cell lymphoma, B-cell chronic lymphocytic leukemia/ small lymphocytic lymphoma, and extramedullary plasmacytoma [14].…”

Peripheral T Cell Lymphoma of Parotid Gland: A Diagnostic Challenge

“…They have increased relapse rate with survival rate of 25-85% (6-48 months) [2]. EBV, Sjogren's disease, CD-56 positivity are associated with poor prognosis (25-40%) [10].…”

Angioimmunoblastic T-Cell Lymphoma and Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma

“…The occurrence of cutaneous or systemic T-cell neoplasms in CLL/SLL patients has been documented in several case reports and case series (Table 1). 12–39 Mechanistically, lymphomagenesis has been linked to the accumulation of oligoclonal or monoclonal T-cell populations with abnormal phenotypes or disrupted functional properties commonly observed in CLL/SLL patients 40,41. Among the 38 systemic T-cell lymphomas reported in CLL/SLL patients so far (Table 1), the majority were diagnosed as peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS),15,16,18,19,21,23,25,26 anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALCL), or ALK-negative ALCL 14,17–20,24…”

“…12–39 Mechanistically, lymphomagenesis has been linked to the accumulation of oligoclonal or monoclonal T-cell populations with abnormal phenotypes or disrupted functional properties commonly observed in CLL/SLL patients 40,41. Among the 38 systemic T-cell lymphomas reported in CLL/SLL patients so far (Table 1), the majority were diagnosed as peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS),15,16,18,19,21,23,25,26 anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALCL), or ALK-negative ALCL 14,17–20,24…”