Clinicopathological characteristics and treatment outcomes of 38 cases of primary thyroid lymphoma: a multicenter study

Abstract

PurposePrimary thyroid lymphoma (PTL) is a rare disease and it has been investigated in a limited number of studies. The present multicenter study evaluated the clinical features and treatment outcomes of PTL.MethodsThe medical records of patients diagnosed with PTL between 2000 and 2013 in three centers were retrospectively reviewed.ResultsThe study included 11 men and 27 women with a median age of 63.3 years (range, 42-83 years). The median follow-up was 56.0 months (range, 3-156 months). Of the 38 patients included, 16 had mucosa-associated lymphoid tissue (MALT) lymphoma, six had mixed MALT and diffuse large B-cell lymphoma (DLBCL), and 16 had DLBCL. Thirty-five patients (92.1%) had early stage (stage I/II) disease. Of the 16 MALT lymphoma patients, 14 were treated by surgery, and radiotherapy (RT) or chemotherapy was combined in five patients. Two patients received RT or chemotherapy alone. Of the six mixed MALT and DLBCL patients, three underwent surgery with chemotherapy and three underwent chemotherapy alone, RT alone, or surgery with RT. All of the 16 DLBCL patients received chemotherapy, and surgery and RT was combined in 4 and 1 patients, respectively. The 5-year survival was 100% for MALT lymphoma (7 of 7) and mixed MALT and DLBCL patients (5 of 5) and 87.5% for DLBCL patients (7 of 8).ConclusionEarly stage PTL has an excellent prognosis when managed by single or combined treatment modalities. Clinicians should consider PTL in patients with underlying Hashimoto's thyroiditis presenting with an enlarging thyroid mass.

Primary Thyroid Lymphoma : An Uncommon Etiology of Compressive Goiter

“…In the case of lymphoma, this lymphoid tissue appears in the condition of chronic inflammation which is a response to infection conditions or autoimmune process (11) . Links among auto-immune disease, chronic antigenic stimulation, and PTL have been demonstrated, and Hashimoto's thyroiditis represents the major risk factor (1,12,14) especially in a delay of 20-30 years after initial diagnosis (5,7,10,12) . Commonly, Hashimoto's thyroiditis is considering as a causal factor of primary thyroid MALT lymphoma, which itself may evolve into aggressive lymphoma (6,12,14,15) , by activating B-cells to secrete antibodies, conducting to hyperplasia or malignant transformation of lymphoid tissue (4) .…”

“…PTNHL of the thyroid gland often affects elderly women (1,5,8,9) aged between 50-80 years and less often younger people aged 40 years (2,3,10) , with typically a history of lymphocytic thyroiditis (4,9,11) . In our study, (12) .…”

“…MALT lymphoma will be identified by the presence of immunoglobulin light chains, pan B-cell antigens, and BCL2 and absence of CD5, CD10 and CD23 (12) ; on PCR, it highlights a monoclonal rearrangement of genes that code for IG (3) , we can also detect a number of specific chromosomal translocations associated with MALT lymphoma: t(11,18)(q21,21); t [14,18](q32,21), t [3,14](p14,q32) and t [1,14](q32,q21) (10) . MCL are characterized by the chromosomal translocation t(11,14)(q13,32).…”

“…Some authors insist on the immunohistochemical examination in case of lymphoma accompanied with Hashimoto's thyroiditis because of the probability of coexistence either the neoplastic and reactive lesions (15) . Nevertheless, most of the authors indicate the superiority of the needle biopsy or surgical biopsy guided by ultrasound study; compared to the FNA; for diagnosis and subtyping (10) . The open surgical biopsy is performed when definitive diagnosis on the identification of the subtype was not possible by the less invasive technique (12) .…”

“…Thus, the FNA cytology is judged not a reliable method (10) , but we notice through recent decades and through a multiple small retrospective studies that the sensitivity and the specificity of the FNAC can be increased if consolidated by the use of the flow cytometry, the immunohistochemistry (IHC) and polymerase chain reaction (PCR) (12) which has the particularity of utility in the analysis of small specimens such as those obtained by FNA (9) . MALT lymphoma will be identified by the presence of immunoglobulin light chains, pan B-cell antigens, and BCL2 and absence of CD5, CD10 and CD23 (12) ; on PCR, it highlights a monoclonal rearrangement of genes that code for IG (3) , we can also detect a number of specific chromosomal translocations associated with MALT lymphoma: t(11,18)(q21,21); t [14,18](q32,21), t [3,14](p14,q32) and t [1,14](q32,q21) (10) .…”