EVALUATION OF SURGICAL AND ONCOLOGICAL OUTCOMES OF INTERSPHINCTERIC RESECTION AND MANUAL COLOANAL ANASTOMOSIS IN THE TREATMENT OF DISTAL RECTAL ADENOCARCINOMA

Introduction Historically, tumors in the distal rectum, close to the anal sphincter, were treated with abdominoperineal amputation to achieve wide, clear margins. Recently, it has been shown that margins of one centimeter are acceptable after chemoradiotherapy (CRT). Thus, for tumors without involvement of the intersphincteric plane, resection of the internal sphincter followed by manual coloanal anastomosis can be performed. Although some series show the safety of this procedure, it is still rarely performed outside specialized centers, making the treatment of distal rectal adenocarcinoma quite heterogeneous.

Objective To evaluate the surgical and oncological outcomes of intersphincteric resection and manual coloanal anastomosis in patients with localized distal rectal adenocarcinoma.

Results A total of 97 patients were included, with T1/T2 tumors (44.3%), T3 (54.6%), and T4 (2.1%). Of these, 48.5% had suspicious mesorectal lymph nodes and 22.7% had lateral pelvic lymph nodes. Pre-neoadjuvant treatment, the intersphincteric plane was at risk or involved in 25%, and tumors were located 0.4 ± 0.9 cm from the anorectal ring. A total of 90.7% underwent neoadjuvant treatment, and 10.2% were initially treated under a watch and wait protocol. Upon restaging, 14.1% still had the intersphincteric plane at risk. The surgical approach was laparoscopic (68%), open (19.6%), and robotic (5.2%). In 12.4%, pelvic lateral lymphadenectomy was performed, and in 6.2%, resection of another organ in a single block. The average hospital stay was 9.4 days, and there was one early reoperation due to internal hernia. The histopathological exam showed clear margins in 90.7%. During long-term follow-up, 7.2% had local recurrence and 24.7% had distant metastasis. A total of 7.2% required a definitive stoma due to pelvic recurrence (n=3), chronic anastomotic complications (n=3), and severe anal incontinence (n=1). After an average follow-up of 1563 days, 67% of the patients were alive without disease.

Conclusion Intersphincteric resection with manual coloanal anastomosis for low rectal tumors has proven to be a safe procedure with satisfactory oncological outcomes. The incidence of local recurrences and distant metastases highlights the importance of continuous and rigorous follow-up. Standardizing this procedure could contribute to a more homogeneous approach to the treatment of distal rectal adenocarcinoma.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
25 April 2025