Table 2

Comparative oncology reveals widespread similarities in cancer development and pathology in between human and rhesus macaques

Cancer in rhesus macaquesRef
AgeSimilar increase in cancer incidence in aging/geriatric population.47
Immune competenceSimilar reports of declining immune competence and TCR repertoire with age, resembling the immune situation in aging patients with human cancer.6 52 53
Viral infectionsRhesus rhadinovirus in SIV-infected rhesus macaques is similarly associated with mesenchymal malignancies as Kaposi’s sarcoma-associated herpesvirus in HIV-infected humans.56 57
Epstein-Barr virus homologue rhesus lymphocryptovirus is associated with B-cell lymphomas and hairy leukoplakia in SIV-infected macaques.58
Papilloma virus is present in wild rhesus macaques (88/117) and is sexually transmitted in breeding colonies.63–65
HPV analog RhPV-1 is associated with penile carcinoma, dysplastic lesions, acetowhitening (35%), and two cervical carcinomas in a breeding colony (n=31, transmission rate 71%).63
Inherited mutationsRhesus equivalent of HNPCC/Lynch syndrome is linked to germline MLH1 promoter deletion, de novo stop codon in MLH1, and deleterious missense mutations in MSH6.67 68
No description of BRCA1/2 involvement in NHP yet, potentially due to the limited germline/phenotype information.
Colorectal cancer
PrevalenceNeoplasia of the gastrointestinal system is the most commonly diagnosed in rhesus macaques with adenocarcinoma of the large intestines as most prevalent tumor.47
SymptomsSimilar clinical signs as in humans including weight loss, intermittent diarrhea, hypoproteinemia, fecal occult blood, and microcytic anemia.47 75 77 78
LocationHumans: Throughout the ascending/transverse/descending/sigmoid colon and rectum.
Rhesus macaques: Mostly right-sided (ileocecal junction, ascending colon).
Precancerous lesionsHumans: Colonic polyps are well established as precancerous lesions.
Rhesus macaques: Polyps are not reported and CRC usually infiltrates within colonic wall.
Progression and metastatic spreadHumans: Metastatic spread is common in late stages and a major factor for CRC mortality, frequently to liver and other distant organs such as lung.
Rhesus macaques: Constriction of the colonic lumen by the primary lesion and blocking passage is the major cause for a humane endpoint in rhesus macaques, treatment resistant anemia (iron/B12 supplement) can be frequently observed, local lymph node metastasis, distant metastatic spread (eg, bone/spine), and abdominal carcinomatosis (eg, omentum, uterus, stomach, pancreas) is observed in certain cases.
Mismatch repair deficiencyMMRd in rhesus CRCs results in microsatellite instability as reported in human CRCs.67 68
Breast cancer
Lifetime incidenceSix per cent in female macaques compared with 13% in American women
(note: under-reporting and difference in risk factor exposure in macaques).
76 92 93
HistologySimilar mammary gland anatomy, development patterns, regression, and sex steroid receptor expression.94
Sex hormonesSimilar patterns of estrogen, progesterone, luteinizing hormone, and follicle stimulation hormone in human, cynomolgus, and rhesus macaques.95
HistopathologySimilar range of atypical hyperplasia, DCIS, and invasive ductal carcinomas reported.76
Progression and metastatic spreadSimilar progression and metastatic spread to axillary lymph nodes, lung, and chest wall can be observed in rhesus macaques and humans.47 76
Receptor expression in BCSubtypes described in humans are similarly observed in rhesus macaques incl. Luminal A (HR+/HER2–), HER2 (HR–/HER2+), and triple-negative BC (HR–/HER2–).76 94
  • BC, breast cancer; CRC, colorectal cancer; DCIS, ductal carcinoma in situ; HER2, human epidermal growth factor receptor 2; HNPCC, hereditary non-polyposis colorectal cancer ; HPV, human papilloma virus; NHP, non-human primates ; RhPV, rhesus specific papillomavirus; SIV, simian immunodeficiency virus; TCR, T cell receptor.