Peptide YY-cells (PYY) in neuroendocrine tumors of rectum

Peptide YY-cells (PYY) persist in grate numbers in lower parts of ileum, colon and rectum, localized in deep parts of Liberkunis crypts. These are „open type" cells, which means they extend from basal membrane to gut lumen. In rectal pathological states these cells are rarely examined. The aim of our study is micromorphological and immunocytochemical PYY-cells examination in rectum neuroendocrine tumours. The document considers thirty (30) cases of rectum neuroendocrinomas, got by polypectomy and gathered in the paraphine blocks. On 5-micrometer cross sections there were used classic method and ABC immunocytochemical technique with an anti PYY (1:1800, DAKO) PYY-cells were found in all histological types of neuroendocrinomas and their marked hyperplasia was verified in tuberculous B-type tumors. PYY Hyperplasia can also be found in the glandulare structured tumors (C-type), -cells were found in all histological types of neuroendocrinomas and their marked hyperplasia was verified in tuberculous B-type tumours where these cells are bigger and usually form tubular structures. The study discussion is about PYY-cell biogenesis and about PYY effect on the tumor biological characteristics. It is also considered a modem aspect at neuroendocrine cells.