P-134 - The prevalence and fate of the defunctioning stoma in anal cancer

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Anal Cancer
Palliative Care
Presenter L. Poynter
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors L. Poynter1, D. Lawes2, H. Wegstapel3, J. Summers1
  • 1Maidstone & Tunbridge Wells NHS Trust, Maidstone/UK
  • 2Maidstone & Tunbridge Wells NHS Trust, Tunbridge Wells/UK
  • 3Medway NHS Foundation Trust, Gillingham/UK

Abstract

Introduction

The surgical pre-treatment preparation for patients with anal cancer remains subject to local preferences in practice. In our region, the Kent Oncology Centre co-ordinates the standardised chemoradiotherapy regime for five acute hospital trusts. The UK national guidance for Intensity-Modulated Radiation Therapy (IMRT) in anal cancer is to perform a defunctioning stoma for tumours invading the vagina or anovaginal fistulation, or for significant faecal incontinence. At the discretion of the clinician is the decision to defunction those who have pain, minor incontinence or tumours at risk of obstructing. This study set out to establish the prevalence of and rationale for defunctioning stoma formation in the regional anal cancer service, and their rate of reversal, with reference to the results obtained from the recent ACT II trial.

Methods

A standardised regime of 28 fractions of radiotherapy with concurrent mitomycin and 5-fluorouracil on weeks one and five was employed, co-ordinated by one oncologist in the unit. A prospectively-maintained database of patients was created and all entries from 2010-2013 were included. Data were collected on demographics, TNM stage, duration of chemoradiotherapy (overall treatment time – OTT) and variance, defunctioning stoma creation and rationale, reversal date and quality of life issues following reversal. These data were correlated with both the IMRT guidelines and the outcomes of the ACT II trial. Kaplan-Meier survival analysis was applied to stoma-free survival to the end of the study period. Unpaired t-test was used to compare mean overall treatment times in both groups.

Results

76 patients were identified during the study period; 63 female and 13 male. 39 patients (51%) had defunctioning stomas. These were performed prior to chemoradiotherapy for palpable anterior tumours in females (n = 20), established ano-vaginal fistulae (n = 11), bulky disease (n = 7) and incontinence (n = 1). The predominant stoma type was a sigmoid loop colostomy (n = 35). Mean OTT was shorter in the non-stoma group (39 days vs. 41 days p < 0.05). Of those patients with stomas, 16 had a successful reversal operation (46%). Median time to reversal was 295 days (range = 128-849 days). One patient required their stoma to be reinstated due to incontinence. There were 11 deaths, 6 of whom had stomas at time of death. Stoma-free survival was 74%, compared to a mean of 87.5% at 3 years in both arms of the ACT II trial. No new recto-vaginal fistulation occurred as a consequence of treatment.

Conclusion

The predominant factor in the decision to create a defunctioning stoma in our cohort was presence of an anterior tumour, without direct invasion or fistulation into the vagina, in female patients. More patients continued to have stomas at the end of the study period compared to the ACT II trial. Although stoma-free survival was 74% in this study, the median time to reversal was beyond that used in the ACT II trial (8 months). The low level of serious post-treatment complications in the survival group, with only one patient requiring a post-treatment permanent reinstatement of stoma, raises the question of whether some patients are being given defunctioning stomas unnecessarily.