Enterohepatic Helicobacter spp. in cats with non-haematopoietic intestinal carcinoma: a survey of 55 cases.

Abstract

Several enterohepatic Helicobacter spp. (EHS) have been isolated from cats. Despite the reported association between EHS infection and intestinal neoplasia in other species, this association has not been explored in cats. In this study, 55 non-haematopoietic feline intestinal carcinoma cases were histopathologically evaluated. In contrast with prior reports, large intestinal (LI) carcinoma was observed with greater frequency (61 %) relative to small intestinal (SI) carcinoma (35 %). There was a significant association between intestinal location and animal gender. Of males examined, 83 % had LI carcinoma, while no such trend was observed in females. Previously described associations between Siamese breed and intestinal carcinoma could not be definitively confirmed, although the Siamese breed may be predisposed to SI carcinoma location. Of all carcinomas examined in this study, 62 % were classified as adenocarcinoma, although mucinous adenocarcinoma (28 %) and solid carcinoma (11 %) were also identified. Tumours were all moderately or poorly differentiated. When considered by intestinal location and histopathologic classification, LI adenocarcinoma was associated with significantly advanced mean age (13 years) when compared to SI adenocarcinoma and LI mucinous adenocarcinoma (mean, 9 years in both cases), which were also frequently encountered. To determine whether EHS might play a role in feline intestinal neoplasia, Helicobacter genus- and species-specific fluorescence in situ hybridization was performed. Of these carcinoma cases, 56 % were positive for Helicobacter spp. and one or more species-specific assay for Helicobacterbilis, Helicobactercanis or Helicobactermarmotae. The presence of EHS was significantly associated with both LI location (68 %) and mucinous adenocarcinoma (92 %). These findings suggest a role for intestinal bacteria in non-haematopoietic feline intestinal neoplasia.