The Impact of HIV on Non-AIDS defining gastrointestinal malignancies: A review

Cancer is the leading cause of morbidity and mortality among people living with HIV (PLWH). Although gastrointestinal (GI) cancers are not associated with HIV, their incidence is rising among PLWH, and yet little is known about how HIV affects their presentation, treatment and outcomes. We searched PubMed using "HIV" and "cancer", "esophageal cancer", "gastric cancer", "stomach cancer", "gastroesophageal cancer", "colorectal cancer", "colon cancer", or "rectal cancer". We included studies comparing an HIV-positive group (n ≥ 4) to an HIV-negative group, with respect to clinical presentation, treatment, or mortality of GI cancers. Of 18 articles that met inclusion criteria, 17 were retrospective, and 13 described patients in the United States. At diagnosis with colorectal, but not pancreatic, gastric, or esophageal cancer, PLWH were younger than patients who were HIV-negative. PLWH did not present with more advanced stage GI cancers than patients who were HIV-negative. Compared to HIV-negative controls, PLWH with colorectal cancer had a higher proportion of right-sided versus left-sided colon cancers and a higher proportion of rectal versus colon cancers. Among patients diagnosed with colorectal or pancreatic cancer, PLWH were less likely to receive cancer treatment than other patients; no studies examined the association of HIV status with treatment for esophageal or gastric cancer. PLWH with GI malignancies had higher all-cause mortality compared to patients who were HIV-negative, but evidence for cancer-specific mortality was limited and mixed. PLWH with GI malignancies were less likely to receive cancer treatment and had higher all-cause mortality than patients who were HIV-negative. Most of the studies focused on colorectal cancer; more studies are needed in pancreatic, gastric and esophageal cancer. Future studies should investigate the effects of HIV on cancer-specific mortality, especially among patients in low- and middle-income countries, including those with high HIV prevalence.