A comparison of colorectal cancer in Nigerian and North American patients: Is the cancer biology different?

Background Of the 24 million people predicted to have cancer by 2050, 70% will live in low- and middle-income countries (LMIC). As a result, cancer care is becoming a priority for health care systems in West Africa. This study compares the presentation and pattern of spread of colorectal cancer (CRC) observed in a hospital in West Africa with that of a North American referral center. Methods Data on all adults presenting with CRC at a hospital in Nigerian patients (West Africa; 1990–2011) and all adults with stages III or IV CRC at a specialty hospital in (New York City, New York, North America; 2005–2011) were examined retrospectively. Demographic data, stage of disease, site of metastasis, and survival were compared. Results There were 160 patients identified in West Africa and 1,947 patients identified in North America. Nigerian patients were younger (52 vs 59 years; P < .01) and presented with a later stage of disease (58% stage IV vs 47%; P < .01). Site of disease presentation was different between West African and North American patients ( P < .01); 2.2% of West African patients presented with liver metastases only compared with 48.1% of North American patients. Conversely, 61.3% of patients in West Africa presented with peritoneal metastases only compared with 5.4% in North America. Overall survival stratified by stage at presentation (III/IV) showed worse prognosis for patients in either stage subgroup in Nigeria than North America. Conclusion We found differences in the presentation, metastatic pattern, and outcomes of CRC in Nigerian (West Africa) when compared with New York City (North America). Late detection and differential tumor biology may drive the differences observed between the sites. Future studies on early CRC detection and on tumor biology in LMIC will be critical for understanding and treating CRC in this region.