Perineal Reconstruction after Extralevator Abdominoperineal Excision (ELAPE): Current Trends-What Is the Future?

Aim

Extralevator abdominoperineal excision (ELAPE) is becoming the main treatment modality for locally advanced low rectal cancer as substantial evidence link ELAPE with superior oncological outcomes than conventional abdominoperineal excision.¹

However, the extended resection performed in ELAPE creates an extensive three-dimensional soft tissue perineal defect within a previously irradiated field, increasing perineal wound complications to 40–60%.¹ Various methods have been described in order to reduce perineal wound morbidity including primary closure, flaps and biological meshes but the ideal technique remains controversial, making perineal reconstruction post-ELAPE challenging for the plastic surgeon.¹

The primary objective of this study is to appraise the post-ELAPE perineal reconstruction techniques in a UK tertiary institution. The secondary aim is to identify the technique that fulfils the principles of an ideal perineal reconstruction (function, reliability, and cosmesis).

Methods:

All patients that had undergone ELAPE and perineal reconstruction between 2009 and 2017 were reviewed retrospectively. Data included patients’ demographics, neo-adjuvant chemo-radiotherapy, histopathology, imaging, duration of surgery, reconstructive method, follow-up period and complications.

 

Results:

Seventy-three (n=73) cases were identified. 81% of the patients had neo-adjuvant chemoradiotherapy. Gluteus maximus muscular flaps (35%, 26) were associated with a higher complication rate(62%). These included perineal collection(36%), perineal pain(35%) and perineal hernia(19%).

Vertical Rectus Abdominal Muscular flaps’ (9,5%, 7) complication rate was 33% (1 flap necrosis, 1 perineal sinus and 1 perineal collection). Lotus petal (8%, 4) and Inferior Gluteal Artery Perforator V-Y advancement flaps’ (8%, 4) complication rates were 75% and 16% respectively. The above flaps required an average of 134 min (range 118-145) additional operating time.

Internal pudendal artery (IPA) perforator flaps, predominantly the PTO (Perineal Turn Over) flap², were introduced in 2014 and gained popularity (35%, 26) as they are quick (mean operating time 52 min) and provide good results with only 8.6% complication rate (1 perineal hernia and 1 superficial wound dehiscence). Review of this group's radiotherapy scans showed that IPA perforators are consistently out of radiotherapy zone.

Overall complications in all flaps were higher in irradiated patients and smokers.

Conclusion:

Techniques involving muscular dissection are associated with higher morbidity rates (20-62%) reflecting similar trends in the literature.¹ IPA turnover perforator flaps such as the PTO flap², that do not involve perforator transposition at 90° angle (as in lotus petal flaps) are associated with the lowest morbidity rate. Their concept supports the ideal reconstruction principles:

a) Function: the thick gluteal dermis acts as an autologous (as opposed to biological meshes) dermal vascularised substitute that strengthens the pelvic floor and prevents perineal hernia ²

b) Reliability: the perforators are consistent and always protected from radiotherapy ensuring good flap vascularity; the gluteal subcutaneous fat obliterates the dead space reducing collections and infections.²

c) Cosmesis: recreation of the natal cleft providing good aesthetic outcome.

 

1. Anderin C et al. (2012) Short-term outcome after gluteus maximus myocutaneous flap reconstruction of the pelvic floor following extralevator abdominoperineal excision of the rectum. Colorectal Disease, 14:1060–1064.
2. Chasapi et al. “The Perineal Turn Over (PTO) perforator flap”: A new and simple technique for perineal reconstruction after Extralevator Abdominoperineal Excision (ELAPE). Ann Plast Surg.2017 Nov 21.