 |
|
|
| |
Four Non-AIDS Cancers on the Rise With HIV in Big North American Cohort
|
| |
| |
17th Conference on Retroviruses and Opportunistic Infections, February 16-19, 2010, San Francisco
Mark Mascolini
Cumulative new diagnoses of four non-AIDS cancers--anal cancer, colorectal cancer, liver cancer, and melanoma--rose significantly through age 60 in an NA-ACCORD analysis of more than 96,000 adults with HIV infection [1]. Although cumulative incidence through age 60 fell for two AIDS cancers--Kaposi sarcoma and non-Hodgkin lymphoma--incidence of those two cancers after 1996 still easily outstripped incidence of the non-AIDS cancers. The NA-ACCORD investigators believe their analysis is more accurate than some because it considers declining mortality risk among people with HIV as a competing event, and because it considers "near-lifetime" cumulative cancer risk for people with HIV.
NA-ACCORD combines more than 96,000 HIV-infected adults from 19 cohorts. Michael Silverberg and colleagues determined new diagnoses of seven non-AIDS cancers and two AIDS cancers from before 1996 through 2007 by analyzing medical records, histopathology reports, self report, or cancer registry linkage.
Cumulative incidence for both AIDS cancers by age 60 fell significantly from before 1996 through 2003-2007 in the analysis considering death as a competing risk. For Kaposi sarcoma cumulative incidence dropped from 25.0% before 1996 to 17.8% in 1996-1998, 10.8% in 1999-2002, and 7.4% in 2003-2007 (P for trend < 0.001), while rates of non-Hodgkin lymphoma in those periods were 7.4%, 12.5%, 7.8%, and 5.8% (P for trend < 0.001).
Cumulative incidence of four non-AIDS cancers by age 60 rose significantly over the study period:
· Anal: 1.2% before 1996, 3.0% in 1996-1998, 3.3% in 1999-2002, and 2.9% in 2003-2007 (P for trend < 0.001)
· Colorectal: 0.3% before 1996, 2.6% in 1996-1998, 2.7% in 1999-2002, and 2.3% in 2003-2007 (P for trend < 0.001)
· Liver: 0.2% before 1996, 0.8% in 1996-1998, 1.1% in 1999-2002, and 1.3% in 2003-2007 (P for trend < 0.001)
· Melanoma: 0.1% before 1996, 1.1% in 1996-1998, 1.1% in 1999-2002, and 0.8% in 2003-2007 (P for trend = 0.01)
Cumulative incidence by age 60 did not change significantly for three other non-AIDS cancers: Hodgkin lymphoma, lung cancer, and oropharyngeal cancer.
Silverberg and colleagues noted that AIDS cancers remain common in the current antiretroviral era, with cumulative incidence through age 60 at 10.6% for Kaposi sarcoma after 1996 and 7.7% for non-Hodgkin lymphoma after 1996. In contrast, cumulative incidence through age 60 for the four most common non-AIDS cancers after 1996 was 3.0% for anal cancer, 2.4% for colorectal cancer, 1.1% for liver cancer, and 0.9% for melanoma.
The NA-ACCORD team argued that their competing-risk approach for estimating cancer incidence is more accurate than the standard survival approach, which overestimates cumulative risk, especially in earlier AIDS-era years when the risk of death was higher. People in later eras are more likely to survive with HIV infection and thus to fall victim to cancer.
The investigators cautioned that their analysis is limited because it did not consider trends in cancer screening, smoking, or underlying viral coinfections that could cause anal and liver cancer. "However," they concluded, "our results more accurately describe the overall risk of cancer by considering the declining mortality risk as a competing event in a large cohort collaboration that is representative of the North American HIV epidemic."
Reference
1. Silverberg M, Lau B, D'Souza G, et al. Trends in cumulative incidence of cancer among HIV-infected patients in North America. 17th Conference on Retroviruses and Opportunistic Infections. February 16-19, 2010. San Francisco. Abstract 758. http://www.retroconference.org/2010/PDFs/758.pdf.
|
| |
|
|
|
|
|
