## 2 Materials and Methods
### Results  
The presence and levels of Hps27, Hsp60, Hps70 and, Hsp90 were determined in the tumor tissue itself and in the adjacent parenchyma (AP) of FA and FC. The immunopositivity for Hsp27 was observed in the cytoplasm and the nucleus in tumoral cells while only in the cytoplasm in the cells of the adjacent parenchyma. It was high in all specimens and it did not show significant quantitative differences between the specimens or tissue type: it was 73% in FA and 70% in its AP, and 68% in FC and 47% in its AP (Figure 1).  
The Hsp60 tissue levels were 33% in FA and 7% in its AP with a significant difference (\(p\leq 0.01\)), and in FC the immunopositivity was 74% and 6% in its AP with a significant difference (\(p\leq 0.001\)). In the FA and FC epithelial cells, the immunopositivity was diffuse in the cytoplasm while in the epithelial cells of the AP was also in the cytoplasm but mild and granular. Statistical analysis also, showed a significant difference between FA and FC (\(p\leq 0.001\)) (Figure 2).  
Figure 1: Hsp27 Immunohistochemistryistochemistry. (**A**) Representative images of immunohistochemical results for Hsp27. Magnification 200\(\times\); scale bar 100 \(\upmu\)m. (**B**) The histogram shows statistical results for the immunohistochemical evaluation for Hsp27 in follicular adenoma (FA), adjacent parenchyma of follicular adenoma (AP FA), follicular carcinoma (FC) and adjacent parenchyma of follicular carcinoma (AP FC). Data are presented as mean +5D.  
The results for Hsp70 showed a positivity of 18% and 8% in FA and its AP, respectively, with no statistical difference, and of 55% and 7% in FC and its AP, respectively, with a statistical difference (\(p\leq 0.001\)). The epithelial cells of FC showed a high cytoplasmic positivity while those of FA and the AP of both neoformans, showed a mild and pointed immunopositivity. Statistical analysis also showed a significant difference between FA and FC (\(p\leq 0.001\)) (Figure 3).  
Figure 3: Hsp70 Immunohistochemistryistochemistry. (**A**) Representative images of immunohistochemical results for Hsp70. Magnification 200\(\times\); scale bar 100 \(\upmu\)m. (**B**) The histogram shows statistical results for the immunohistochemical evaluation for Hsp70 in follicular adenoma (FA), adjacent parenchyma of follicular adenoma (AP FA), follicular carcinoma (FC) and adjacent parenchyma of follicular carcinoma (AP FC). Data are presented as the mean +SD. * \(p\leq 0.0001\).  
Figure 2: Hsp60 Immunohistochemistryistochemistry. (**A**) Representative images of immunohistochemical results for Hsp60. Magnification 200X; scale bar 100 \(\upmu\)m. (**B**) The histogram shows statistical results for the immunohistochemical evaluation for Hsp60 in follicular adenoma (FA), adjacent parenchyma of follicular adenoma (AP FA), follicular carcinoma (FC) and adjacent parenchyma of follicular carcinoma (AP FC). Data are presented as the mean +SD. * \(p\leq 0.0001\), # \(p\leq 0.01\).  
The tissue levels of Hsp90 were 25% in FA and 15% in its AP, and were 56% in FC and 33% in its AP with no statistical difference. In all specimens the immunopositivity was cytoplasmic, intense in the FC and FA cells while mild in the cells of the AP. Statistical analysis also showed a significant difference between FA and FC (\(p\leq 0.05\)) (Figure 4).  
Our immunohistochemical observation was also dedicated to the evaluation of the intracellular localization of the Hsp immunopositivity. We observed an accumulation of Hsp60, Hsp70, and Hsp90 in the cytoplasm and of Hsp27 in the cytoplasm and in the nucleus.