Metastatic endocervical adenocarcinoma in a western lowland gorilla (Gorilla g. gorilla): no evidence of virus-induced carcinogenesis.

BACKGROUND

Cervical Cancer is the second most common cancer among women. Nevertheless, similar tumours have only been rarely described in Great Apes. This report characterizes the pathological and molecular features of a metastatic endocervical adenocarcinoma in a Western lowland gorilla (Gorilla g. gorilla).

METHODS

Necropsy and histopathology was performed to identify the cause of the disease in an cachectic 50-year-old western lowland gorilla. Immunohistochemistry for Ki67, oestrogen receptor alpha and ERBB2 was performed to characterize the tumor. In addition, Pan-herpesvirus and Pan-papillomavirus PCR were used to identify a possible viral cause.

RESULTS

The endoccervical carcinoma showed a severe metastatic spread to the lung, brain and bone and was herpesvirus and papillomavirus-negative. Most tumor cells were ERBB2-positive, 15% of tumor cells were Ki67-positive and only few tumor cells had oestrogen receptor alpha expression.

CONCLUSIONS

Histopathologically and immunohistochemically, the tumour had striking similarities to human endocervicial adenocarcinomas of the common type. However, PCR analysis failed to identify herpes- or papillomaviral DNA in the tumor at the time of necropsy, thus leaving the question for cause of the disease open.