Malignant Rhabdoid Tumor in the Gastric Wall of an Aged Orangutan (Pongo pygmaeus)

Abstract

A 34-year-old female orangutan (Pongo pygmaeus) developed renal failure and became uremic. At necropsy, large gastric masses were present around the cardia and in the corpus. Abdominal metastases occurred in the liver, pancreas, and right ovary. Light microscopic examination of the tumor revealed polygonal cells with vesicular nuclei and prominent nucleoli. The growth pattern was predominantly solid. Focal areas contained excentric cytoplasmic intermediate filament inclusions, as identified by immunohistochemistry and electron microscopy. Immunohistochemical procedures demonstrated mainly the vimentin type of intermediate filaments. Except for occasional cytokeratin, other intermediate filament markers and neural, lymphocytic, and histiocytic markers stained negative. The morphologic and ultrastructural characteristics are typical for a malignant rhabdoid tumor, a term used in human pathology to describe a rare and extremely aggressive malignancy of uncertain histogenesis. Although usually located in the infant kidney, a few reports have documented the occurrence of similar lesions in extrarenal sites of adults. In human tumors, vimentin is often combined with the expression of cytokeratins. The sparsity of the cytokeratin filaments in this case might be due to species-specific variations and/or may reflect the hypothesis of a phenotypic concept encompassing a spectrum of histogenetic diversity.

Neoplasia and Proliferative Disorders of Nonhuman Primates

“…Gastric stromal tumors have been reported in two female rhesus monkeys (Banerjee et al, 1991) as well as a baboons, spider monkeys, and chimpanzees (Saturday et al, 2005;Bommineni et al, 2009). A malignant rhabdoid tumor in the gastric wall was described in an aged orangutan (Pongo pygmaeus) (Schauer et al, 1994), a gastric sarcoma was described in a squirrel monkey (S. sciureus) (McClure, 1979), an adenocarcinoma in a de Brazza's guenon (Cercopithecus neglectus) (Yanai et al, 1997), and a cardiac squamous cell carcinoma in an orangutan (Ohgaki et al, 1984).…”

Cutaneous Rhabdoid Tumor in a Cat

“…In nonhuman species, spontaneous RTs have been reported only in the gastric wall of an aged orangutan, 9 in the brain of a young dog, 10 and in the orbit of a young horse. 3 The pathologic findings in these cases resembled those in human RTs.…”

The use of ultrasound and computed tomography for the diagnosis of a squamous cell carcinoma of the oesophago-cardial region of the stomach in a rhesus monkey

“…In most reported cases of malignant neoplasmas in monkeys, the animals died a spontaneous death after a prolonged period of suffering (Ratcliffe 1940, Hisaw & Hisaw 1958, Newberne & Robinson 1960, Allen et al 1970, Chesney & Allen 1973, Oghaki et al 1984, Banerjee et al 1991, Schauer et al 1994. Typically, the animals were treated with symptomatic therapy, and were diagnosed postmortem.…”