TGF-BETA-1 IMMUNOSTAINING PATTERNS AND LOCATIONS IN ADENOMA WHICH LATER RECURRED

To investigate whether the immunohistochemical pattern of TGF beta 1 m ay be a marker of relapse for adenomatous pathology, 18 follicular ade nomas, surgically removed by hemithyroidectomy between 1977 and 1982, were studied. The adenomas were divided into two groups according to t he presence (group 1, N=9) or absence (group 2, N=9) of nodules recurr ing in the residual thyroid tissue. The presence and location of TGF b eta 1 were evaluated a posterior by immunohistochemistry in the remove d adenoma, Fifty randomly selected subcapsular follicles were studied in each adenoma in order to evaluate the percentage of positive follic les and TGF beta 1 intra-thyrocyte location, In adenoma of group 1, th e percentage of positive follicles for TGF beta 1 was lower (80%) than in adenoma of group 2 (84%); this was, however, not statistically sig nificant. The location of TGF beta 1 was mainly at the cell base of th e epithelial cells in the microfollicles of group 1, but was dominant at the cell apex in group 2 (p <0.01). In conclusion, adenoma recurren ce is independent of TGF beta 1 production; it may be due to an abnorm al TGF beta 1 regulation in response to hyperplasiogenic stimuli.