Systematic review of outcomes after salvage abdominoperineal resection for persistent or recurrent anal squamous cell cancer

Standard definitive treatment for patients with a new diagnosis of squamous cell carcinoma of the anus (SCCA) is chemoradiation.  Up to 30% of these patients will require a salvage abdominoperineal resection (APR) for either persistent or recurrent disease. Studies looking at outcomes after APR for SCCA have been limited to single centres with limited number of patients. The objective of this systematic review was to assess cancer related outcomes in patients with either (i) persistent or (ii) recurrent SCCA.  

Articles were included in this review if they assessed short or long term outcomes in patients undergoing salvage APR for persistent or recurrent SCCA.  EMBASE and MEDLINE were searched.  The primary outcomes of this review were overall survival (OS), disease free survival (DFS), and locoregional recurrence or metastatic disease.  Secondary outcomes included wound and other perioperative complications.

A total of 200 studies were identified, with 20 studies meeting our inclusion criteria. The median time to salvage APR was 2.8 months (IQR 2.6-2.8 months, 4 studies) for persistent disease and 25.6 months (IQR 15 - 32.7 months, 4 studies) for recurrent disease. The median 5-year OS was 47% (IQR 33-59.7%, 9 studies) for persistent disease and 43.5% (IQR 17.5-68.6%, 10 studies) for recurrent disease. The median 5 year DFS was 33.6% (range 31.1-36%, 2 studies) for persistent disease and 53.1% (range 48.2-58%, 2 studies) for recurrent disease.  A median of 47% of patients (IQR 39.7-58.5%, 15 studies) developed locoregional recurrence or metastatic disease. The median wound complication rate was 38.9% (IQR 18.6 – 56.4%, 17 studies) and the median perioperative mortality rate was 0% (IQR 0 – 1.9%, 17 studies).

This current review included 20 studies assessing outcomes following salvage APR for SCCA. Limitations of this review include small sample sizes from single institutional studies, as well as heterogeneity in disease definitions and outcomes.