Comparative findings of lymphocytic thyroiditis and thyroid lymphoma.
OBJECTIVE
To compare the cytologic features of histologically proven lymphocytic (Hashimoto's) thyroiditis (Hashimoto's thyroitidis) and primary thyroid lymphomas (TL).


METHODS
Clinical histories, smears (stained with Diff-Quik, Papanicolaou stain or hematoxylin and eosin [HE]) and surgical specimens (HE slides) were reviewed in 25 cases of lymphocytic thyroiditis and 12 of thyroid lymphomas.


RESULTS
Surgical specimens of thyroiditis were obtained for other medical reasons: goiter and compressive symptomatology in 21 cases and neoplasms in 4 (2 papillary carcinomas, 1 follicular carcinoma and 1 oncocytic adenoma). Seven cases were primary lymphomas, and 5 were secondary. Histologically there were 6 large B-cell lymphomas, 2 mantle cell lymphomas, 1 Burkitt lymphoma, 2 mucosal-associated lymphoid tissue lymphomas in blastic transformation and 1 of unknown type. Sensitivity for the diagnosis was 67.5% for HT and 92.3% for lymphoma.


CONCLUSIONS
A heterogeneous population of small and large lymphocytes was the most frequent pattern in both diseases. The presence of a monotonous population of large lymphocytes or, more rarely, of small cells indicates a probable TL. Plasma cells favor HT. Other techniques are mandatory for the differentiation of cases with inconclusive diagnoses.
Lerma
Enrique
E
Department of Pathology, Hospital de la Santa Creu i Sant Pau, Autonomous University, Barcelona, Spain. elerma@hsp.santpau.es
Arguelles
Rosa
R
Rigla
Mercedes
M
Otal
Concha
C
Cubero
José-Maria
JM
Bagué
Sylvia
S
Carreras
Ana M
AM
Eulalia
Esteva
E
Gonzalez-Campora
Ricardo
R
Galera
Hugo
H
Prat
Jaime
J
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000378:metabolism; D002277:Carcinoma / Q000473:pathology; D003937:Diagnosis, Differential; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007037:Hypothyroidism / Q000473:pathology; D007150:Immunohistochemistry; D008214:Lymphocytes / Q000473:pathology; D008223:Lymphoma / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000473:pathology*; D013967:Thyroiditis, Autoimmune / Q000473:pathology*
D001323:Autoantibodies