[Lymphocytic infiltration in thyroid neoplasms. Preliminary prognostic assessments].
BACKGROUND
It is known that the immune system is involved in several thyroid diseases and in the reaction against cancer progression. We have therefore evaluated lymphocytic infiltration in the slices of surgically removed thyroids in patients affected by thyroid carcinomas, to further clarify the anatomic and clinical characteristics of this pathology and the possible prognostic correlations.


METHODS
Thirty-eight patients, 7 men and 31 women, aged 23-73 years, were studied. They underwent total or subtotal thyroidectomy for thyroid carcinoma. The histopathological findings were: papillary carcinomas (P): 22 cases; follicular carcinomas (F): 10 cases; undifferentiated carcinomas (U): 3 cases; other types (e.g., medullary carcinoma, M): 3 cases.


RESULTS
The lymphocytic infiltration was evaluated in 4 different grades. The following results, regarding the different histological types, were found: grade 0 (no lymphocytic infiltration) in 10 cases (6 P, 2 F, 1 U, 1 mixed); grade 1 (poor lymphocytic infiltration, equivalent to a non specific inflammatory reaction) in 21 cases (11 P, 6 F, 2 U, 1 M); grade 2 (moderate lymphocytic infiltration) in 4 cases (2 P, 2 F); grade 3 (plentiful lymphocytic infiltration) in 3 cases (2 P, 1 trabecular carcinoma). In 3 patients a lymphocytic (Hashimoto's) thyroiditis was also present. The follow-up, 2 years after surgery, showed, among 17 patients examined, local recurrence and/or lymph node localization in 8 cases (the lymphocytic infiltrations was: grade 1: n = 6; grade 0: n = 2; no one exhibited a higher grade) and apparent remission in 9 (grade 3: n = 2; grade 2: n = 1; grade 1: n = 6; no one exhibited a grade 0 lymphocytic infiltration).


CONCLUSIONS
In most patients a poor or absent infiltration was found. In 7 cases, however, the infiltration was moderate or high. In our experience, no correlation between the histologic type and the infiltration grade was observed. However, in no patient with recurrence of neoplasia a relevant (grade 2-3) infiltration could be observed; patients without recurrence often showed a grade 2-3 infiltration, and no one of them showed a grade 0. The significance of lymphocytic infiltration in thyroid carcinoma is not well clarified. In fact, a few studies underline a possible unfavourable role, since a relevant infiltration seems to be associated with a weak cell-mediated immunity, mostly in follicular and anaplastic carcinomas. However, most data support the hypothesis that the lymphocytic infiltration is a good prognostic feature: in fact, it can be often found in papillary carcinomas and in juvenile thyroid carcinomas, both characterized by a good long-term prognosis.


CONCLUSIONS
Our preliminary data underline the opportunity of comparing the clinical course of the disease, the histologic grading and the tumour staging with the lymphocytic infiltration grade, an easily available pathologic datum, for a better prognostic evaluation of patients.
Mancini
A
A
Istituti di Endocrinologia e Anatomia, Università Cattolicà del SacroCuore, Roma.
Rabitti
C
C
Conte
G
G
Gullotta
G
G
De Marinis
L
L
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D016246:Lymphocytes, Tumor-Infiltrating; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013964:Thyroid Neoplasms / Q000473:pathology*
L'infiltrato linfocitario nelle neoplasie tiroidee. Preliminari valutazioni prognostiche.