Background: Preoperative biochemical diagnosis of acromegaly is based on the determination of the serum levels of insulin-like growth factor 1 (IGF-1) and growth hormone (GH) in the oral glucose tolerance test. In turn, although assumptions concerning the tumour hormonal phenotype may be made on the basis of biochemical tests, the final determination of the exact adenoma profile is possible only on the basis of postoperative immunohistochemical evaluation. Due to the high importance of both – preoperative determination of the concentration of IGF-1 and postoperative immunohistochemical examination of pituitary tumour, the aim of this study was to compare these parameters. Material and methods: The study group consisted of 21 patients with acromegaly and 15 with clinically nonfunctioning pituitary adenoma (CNFPA). In all the patients IGF-1 and prolactin (PRL) concentrations in serum were measured by enzyme–amplified chemiluminescent immunoassay. The immunohistochemical diagnose of the adenoma was achieved with the primary antibodies against the pituitary hormones, the α-subunit and Ki-67 – proliferation indicator. Results: In patients with acromegaly immunohistochemistry besides monohormonal tumours – “pure” somatotropinoma, also somatoprolactinoma and adenoma plurihormonale have revealed. The mean concentrations of IGF-1 were 702, 1480 and 915 ng/mL respectively in each of these groups. In most cases the proliferation index Ki-67 was less than one. In patients with CNFPA, the IGF-1 levels were mostly in reference values and almost in half of cases the Ki–67 value was above one. Conclusions: There are statistically significant differences between preoperative serum IGF-1 concentrations in the somatoprolactinoma group and other adenoma phenotypes in acromegaly patients. This result may suggest the possible link between additional prolactin component with very high concentration of IGF-1 in patients with acromegaly.

Niezliczona liczba informacji docierająca do nas z zewnątrz powoduje, że aby nie zgubić się w informacyjnym gąszczu podejmujemy próbę oceny. Najczęściej przy ocenie pomijamy niektóre (wydawać by się mogło) istotne informacje bądź – z drugiej strony – przypisujemy większą rangę innym, co w konsekwencji tworzy nam prosty ogląd otaczającej nas rzeczywistości. Taki ogląd przyczynia się do rozwoju strategii, którą nazywamy kategoryzacją. Kategoryzowanie rzeczywistości społecznej (poprzez częste powtarzanie i utrwalanie oraz brak głębszej analizy) w dużym stopniu wpływa na powstawanie stereotypowych skojarzeń. W tej sytuacji pomocne mogą być media, które przychodzą z pomocą i utrwalają – albo zmieniają ugruntowany obraz (stereotyp).

Introduction. Approximately one third of pituitary adenomas are manifested neither by specific symptoms of hormone overproduction nor by elevated blood levels of pituitary hormones. However, these tumours, diagnosed before surgical intervention as clinically non-functioning pituitary adenomas (CNFPAs) express in majority different pituitary hormones, as can be revealed by means of immunohistochemical examination. One of the pituitary hormones which may be expressed in CNFPAs is prolactin (PRL) but the clinical and pathological data on this condition are very scarce. Material and methods. Sixty two pituitary adenomas, diagnosed before surgery as CNFPAs, were immunoassayed with antibodies against PRL, growth hormone (GH), luteinizing hormone (LH), follicle stimulating hormone (FSH), thyrotropin (TSH), alpha subunit (alpha-SU), corticotropin (ACTH) and dopamine receptor type 2. In a proportion of the patients the presurgical concentrations of insulin-like growth factor 1 (IGF-1) were estimated by means of enzyme-amplified chemiluminescence assay. Results. Twenty-three (37.1%) of the examined CNFPAs presented the positive immunoreaction with anti-PRL antibody. Most cases concerned women. Only in two cases (one woman and one man), PRL was the unique hormone expressed in the tumour. In the remaining adenomas PRL immunopositivity was accompanied by GH expression-17, LH or free bLH-13, FSH-2, free a subunit-4 or by ACTH-5 tumours. Seven (30.43%) of them were recurrent in comparison with 12.8% PRL-immunonegative recurrent CNFPAs. Dopamine receptors were positively immunostained in all the investigated PRL-immunopositive and all PRL-immunonegative adenomas. Conclusions. Our data confirm the observations that monohormonal silent prolactinomas are very rare but frequently silent PRL often co-expressed with GH or LH. Although in the whole population of patients with CNFPAs both sexes are equally represented, in the case of silent prolactinomas the female sex is prevalent. The observation of the higher rate of recurrent tumours within PRL-immunopositive adenomas versus PRL-immunonegative CNFPAs has to be confirmed on the larger material.