E. Vo1, B. A. Kimbrough1, S. S. Awad1,2, N. S. Becker1,2, L. W. Chiu1,2, L. Gillory1,2, D. S. Lee1,2, K. Makris1,2, G. Chen1,2, N. N. Massarweh1,2,3, H. S. Tran Cao1,2, C. Y. Chai1,2 1Baylor College Of Medicine,Houston, TX, USA 2Michael E. DeBakey Veterans Affairs Medical Center,Houston, TX, USA 3VA HSR&D Center For Innovations In Quality, Effectiveness And Safety, Michael E. DeBakey VA Medical Center,Houston, TEXAS, USA
Introduction: The incidence of anal cancer in the US has been steadily increasing since the 1970s. Of the known risk factors for anal carcinoma including HIV, HPV infection, history of anogenital warts, organ transplant, and tobacco use, HIV status poses the greatest risk but has not been clearly defined as a prognostic indicator. The objective of our study was to evaluate the clinical differences between HIV and non-HIV patients with anal carcinoma over the past 15 years at our institution.
Methods: We performed a retrospective review of an institutional tumor registry for all patients with histologically confirmed diagnosis of anal carcinoma from 2000-2015. Baseline demographic and clinical data including gender, age at diagnosis, histologic type, HIV status, treatment history and stage at initial diagnosis were collected. Descriptive and univariate analyses were performed to compare HIV vs non-HIV patients. Cancer-specific survival was calculated using Kaplan-Meier method.
Results: A total of 77 patients were included in our review (43% with HIV). The majority of our patients were male (92%), white (73%), with invasive squamous cell carcinoma (66%). HIV patients were diagnosed at a younger age (51 vs. non-HIV 60 years, p<0.01) and earlier stage 0-1 (63% vs. non-HIV 36%, p=0.01). Local excision was offered at a higher rate for HIV patients (52% vs. non-HIV 30%, p=0.05) with less receiving chemoradiation (42% vs. non-HIV 66%, p=0.04) and salvage APR (6% vs. non-HIV 16%, p=0.29). No statistically significant difference in cancer-specific 5-year survival was noted between HIV vs. non-HIV patients (p=0.64).
Conclusion: Although HIV patients are likely to be diagnosed with anal carcinoma at a younger age and at an earlier stage due to awareness of HIV as a risk factor, there was no difference in cancer-specific 5-year survival between HIV and non-HIV patients. Further study is warranted to examine factors which may influence survival in HIV patients in the era of effective antiviral therapy, and a high suspicion for anal cancer remains key to early detection in patients with anal or perianal lesions or symptoms.