Necessary circumferential resection margins to prevent rectal cancer relapse after abdomino-peranal (intersphincteric) resection. Langenbecks Arch Surg. 2016;401:189-194. [PMID: 26886280 DOI: 10.1007/s00423-016-1383-6]

Evaluation of long-term oncological outcomes of inter-sphincter resection compared with abdominoperineal resection for treatment of ultra-low rectal cancers: a single center 5-year experience

Objectives

Abdominoperineal resection (APR) is considered the gold standard surgical treatment for ultra-low rectal cancer. Anus-preserving alternative procedures have been tested to avoid the need for a permanent colostomy. The present study compares the functional and oncological outcomes of the traditional APR methods with inter-sphincteric resection (ISR).

Methods

Sixty patients with ultra-low rectal cancers that underwent tumor resection using the ISR and APR methods were compared retrospectively. Patients' demographic information as well as tumor characteristics were evaluated. All patients were followed after the operation every three months for two years, and then every six months for at least three years.

Results

Thirty-four (56.6%) patients were male, and 26 (43.3%) were females, which showed no statistical significance between the two groups. The mean tumor distance from the anal verge in the APR group was 5.11±0.06 cm and in the ISR group was 5.22±1.1 cm. In the APR group, 9 (30%) patients developed primary tumor recurrence, while in the ISR group, 10 (33.3%) patients had relapses. The observed difference was not statistically significant. However, the study showed that patients with a T stage of T2 or higher had a higher probability of tumor recurrence.

Conclusion

There is no significant difference in the efficacy of the ISR method compared with the conventional APR for the treatment of ultra-low rectal cancer.

Functional outcomes after intersphincteric resection for ultralow rectal cancer

Anal function is one of the most important parameters for evaluating the efficacy of intersphincteric resection (ISR) for the treatment of ultralow rectal cancer (< 1 cm from the anal sphincter). Although there have been no results hitherto from randomized controlled trials to verify the clinical benefits of the ultimate sphincter-sparing technique, increasing evidence demonstrates that ISR significantly decreases the rate of permanent stoma and patients could acquire satisfied functional results after surgery. This review discusses the short-term and long-term functional outcomes, risk factors for anal incontinence, and surgical method and approach of ISR.

Intersphincteric resection for low rectal cancer

For low rectal cancer located < 5 cm from the anal verge, abdominoperineal resection (APR) with permanent sigmoid colostomy is usually used to ensure the R0 resection. Sphincter saving surgery has emerged in the last 20 years, and the introduction of intersphincteric resection (ISR) can successfully preserve the anal function and guarantee a radical tumor resection for patients with ultra-low lying tumors. Therefore, the use of APR has been consistently declining worldwide. Recently, a growing body of research on ISR has been reported. However, more evidence based results are needed to clarify some issues about ISR. In the current review, we discuss the indications for ISR and the oncological and functional outcomes following the procedure. Some technique issues of ISR are also discussed.