The thyroidal lymphoid infiltrate (TLI) in Hashimoto's thyroiditis (HT) represents the substrate from which thyroid lymphoma (TL) may arise. The aim of the study was to assess the TLI in HT with flow cytometry (FC) evaluating the κ/λ light chain ratio and its molecular assessment. FNA was performed in 34 HT patients with nodular or diffuse palpable enlargement of the gland to prepare traditional smears, FC immunophenotyping and RNAlaterTM suspensions for molecular assessment. FC used antibodies were: CD3, CD5, CD10, CD19, κ and λ light chains. In four cases, high molecular weight DNA was extracted and used for polymerase chain reaction (PCR) to amplify the variable diversity joining (VDJ) region of the heavy chain Ig genes (IgH). A statistical analysis was performed to evaluate possible association between the percentage of the expressing cells (≤20%, >20%) and as κ/λ ratio. FC showed T-cells (CD3+,CD5+) in all the cases, T-cells and B-cells (CD19+,CD10+/-) lymphocytes in 22 cases. Light chains were expressed in 30 cases; in 13 cases in less than 20% of the gated cells and in 17 cases in more than 20%. Five cases showed small κ/λ ratio imbalances and PCR analysis showed diffuse bands in the gel and Gaussian curves at the heteroduplex. Statistical analysis showed a significant association between light chain restriction and low light chain expression (P<0.005). Small light chain imbalances in HT are not sustained by heavy chain Ig gene (IgH) rearrangements. FNA coupled with FC may contribute to the discrimination of florid TLI from non-Hodgkin's lymphoma.
Light chains expression of lymphoid infiltrate in fine-needle cytology of Hashimoto thyroiditis / P., Zeppa; Cozzolino, Immacolata; Troncone, Giancarlo; Malapelle, Umberto; M., Russo; Vetrani, Antonio; Palombini, Lucio. - (2009). (Intervento presentato al convegno 22° European Congress of Pathology. tenutosi a Firenze (IT). nel 4-9 settembre, 2009).
Light chains expression of lymphoid infiltrate in fine-needle cytology of Hashimoto thyroiditis.
COZZOLINO, IMMACOLATA;TRONCONE, GIANCARLO;MALAPELLE, UMBERTO;VETRANI, ANTONIO;PALOMBINI, LUCIO
2009
Abstract
The thyroidal lymphoid infiltrate (TLI) in Hashimoto's thyroiditis (HT) represents the substrate from which thyroid lymphoma (TL) may arise. The aim of the study was to assess the TLI in HT with flow cytometry (FC) evaluating the κ/λ light chain ratio and its molecular assessment. FNA was performed in 34 HT patients with nodular or diffuse palpable enlargement of the gland to prepare traditional smears, FC immunophenotyping and RNAlaterTM suspensions for molecular assessment. FC used antibodies were: CD3, CD5, CD10, CD19, κ and λ light chains. In four cases, high molecular weight DNA was extracted and used for polymerase chain reaction (PCR) to amplify the variable diversity joining (VDJ) region of the heavy chain Ig genes (IgH). A statistical analysis was performed to evaluate possible association between the percentage of the expressing cells (≤20%, >20%) and as κ/λ ratio. FC showed T-cells (CD3+,CD5+) in all the cases, T-cells and B-cells (CD19+,CD10+/-) lymphocytes in 22 cases. Light chains were expressed in 30 cases; in 13 cases in less than 20% of the gated cells and in 17 cases in more than 20%. Five cases showed small κ/λ ratio imbalances and PCR analysis showed diffuse bands in the gel and Gaussian curves at the heteroduplex. Statistical analysis showed a significant association between light chain restriction and low light chain expression (P<0.005). Small light chain imbalances in HT are not sustained by heavy chain Ig gene (IgH) rearrangements. FNA coupled with FC may contribute to the discrimination of florid TLI from non-Hodgkin's lymphoma.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
