Spontaneous squamous cell carcinomas in 13 baboons, a first report in a spider monkey, and a review of the non‐human primate literature

Abstract

Background Squamous cell carcinoma (SCC) is a neoplastic proliferation of epithelial cells undergoing squamous differentiation and represents a diagnostic challenge in nonhuman primates (NHP), especially in baboons with perineal SCC. Methods Fourteen SCC (13 baboons, 1 spider monkey) were identified over a 20-year period. A literature search identified 86 additional published cases of spontaneous NHP SCC. Results SCC was most commonly reported in macaques, baboons, marmosets, and squirrel monkeys. Metastasis occurred in 23%, of NHP. The most frequently reported primary locations were the oral cavity, integument, esophagus, and cervix-uterus. Perineal SCC occurred mainly in baboons. All reported SCC in marmosets occurred in the head. Nasal cavity SCC was only reported in male marmosets. All reported pulmonary SCC occurred in males, mostly in tree shrews. Conclusions SCC is a common neoplasm in NHP and exhibits species differences. NHPs may provide a useful SCC animal model.

Meeting Report

“…Squamous cell carcinoma was twice as common in females as males, and all reported perineal lesions were in females. 16,17,26 Squamous cell carcinoma often presents as a chronic, nonhealing wound of the sex skin and is frequently initially diagnosed as trauma, which is common on the sex skin, leading to prolonged and ineffective therapy. Another differential diagnosis of nonhealing lesions of the sex skin in baboons is African histoplasmosis ( Histoplasma capsulatum var.…”

Neoplasia and Proliferative Disorders of Nonhuman Primates

“…In man, squamous cell carcinoma is commonly associated with prolonged exposure to UV radiation; however a similar pathogenesis has not been studied extensively in macaques. Squamous cell carcinoma has been reported to arise spontaneously in the skin of rhesus (Migaki et al, 1971;Hubbard et al, 1983) and cynomolgus macaques (Morin et al, 1980), baboons (Haddad et al, 2009), a white-lipped tamarin (Richter and Buyukmihci, 1979), and a sooty mangaby (Morales et al, 2006) (Figure 6.18). A solitary case of facial squamous cell carcinoma is reported in an African green monkey that was chronically exposed to the mycotoxin sterigmatocystin (Fincham et al, 1982).…”

“…In the cynomolgus macaque both a nasal adenoma (Kaspareit et al, 2007) and an olfactory neuroepithelioma (Correa et al, 1975) have been described. Tracheal squamous cell carcinomas are rare, but have been described in the baboon (Haddad et al, 2009) (Figure 6.20). Nasal adenocarcinomas have been reported in fat-tailed lemurs (Remick et al, 2009).…”

“…A solitary case of facial squamous cell carcinoma is reported in an African green monkey that was chronically exposed to the mycotoxin sterigmatocystin (Fincham et al, 1982). Cases of squamous cell carcinoma in baboons are most common in females around the perineal region; however whether this is illustrative of a specific pathogenesis is unknown (Haddad et al, 2009). In man, UV radiation is also associated with melanomas and basal cell tumors.…”

On the apparent rarity of epithelial cancers in captive chimpanzees

“…On the other hand, when larger populations of monkeys have been surveyed, the occurrence of carcinomas is more evident [26,[28][29][30]. But even in a large series of baboons surveyed for squamous cell carcinomas, only 13 cases were found in more than 3000 animals in captivity [31].…”