D. J. Kent1, J. J. Blank1, K. Y. Hu1, T. J. Ridolfi1, K. A. Kudwig1, Y. Liu1, L. E. Rein1, C. Y. Peterson1 1Medical College Of Wisconsin,Division Of Colorectal Surgery,Milwaukee, WI, USA
Introduction:
Anal cancer is most often treated with the Nigro protocol, a combined chemoradiation (CRT) regimen. Pelvic radiation can lead to long-term sphincter damage, decreasing bowel function. Wide local excision (WLE) can be used for small tumors and leaves anal sphincter muscles intact. A Salvage Abdominoperineal Resection (APR) is used for persistent or recurrent tumors and results in a permanent colostomy. There is a relative absence of research exploring bowel function and quality of life after treatments for anal cancer. We posit that bowel function in CRT anal cancer patients will worsen after treatment but will then improve over time with recovery. We aim to explore the relationship between bowel function and quality of life after any anal cancer treatment over time.
Methods:
The EQ-5D-5L quality of life survey (QOL) and the Memorial Sloan-Kettering Cancer Center Bowel Function Index (BFI) are administered at each appointment with Colorectal Surgery at Medical College of Wisconsin. We conducted a retrospective review of patients treated at our institution for anal squamous cell carcinoma from 1/1/2008 to 1/30/2018. We collected BFI, QOL, demographics, treatment used, and timeline of care. Patients were stratified by treatment as WLE, CRT, or Salvage APR. Statistical analysis used Fisher’s exact test, Kruskal-Wallis test, Spaghetti plot, mixed linear effects modeling and regression analysis.
Results:
There were 59 patients seen within the first 5 years after treatment. The average age was 58 (SD = 11.6) and there were 37 (63%) women. Forty-two patients underwent CRT, 10 underwent WLE and 7 patients required Salvage APR. There were no differences in comorbidities. Over 5 years after treatment, CRT patients' BFI scores remained stable with slight upward trend in the first 3 years and then a return to baseline. WLE patients showed stable BFI scores. Salvage APR patients had decreasing BFI scores in the first 3 years after treatment (Figure 1A). Mixed effects modeling assuming linear effect showed no significant difference in BFI or QOL scores between groups (Figures 1B, 1C). Univariate linear regression did not identify any predictors of poor bowel function.
Conclusion:
Bowel function after anal cancer treatment remains stable over time and does not significantly vary between treatment modalities. Quality of life is preserved with all treatment options. The study is limited by few patients with pre-treatment BFI and QOL scores and high variability in scores between patients which could have skewed long-term results. Understanding how treatment impacts bowel function compared to pre-treatment function would be meaningful and we plan to further investigate patients with pre-treatment scores to investigate this.
