Published online Jul 15, 2020. doi: 10.4251/wjgo.v12.i7.732
Peer-review started: December 30, 2019
First decision: April 2, 2020
Revised: May 28, 2020
Accepted: June 14, 2020
Article in press: June 14, 2020
Published online: July 15, 2020
Processing time: 197 Days and 14 Hours
The primary tumor staging of anal canal carcinomas is based on tumor dimension which is clinically and radiologically assessed. Novel tumor staging, based on depth of tumor invasion assessed by endorectal ultrasonography (US), have been proposed and have claimed to potentially affect initial treatment as well as prognosis.
Several authors reported that the staging based on tumor diameter is not an independent prognostic variable. If a different staging system could more accurately reflect the prognosis, it could be used not only to better predict outcome, but also to tailor the treatment.
To evaluate the possible prognostic role of a staging system based on tumor penetration into the anal wall, in comparison with the traditional staging.
This is a retrospective evaluation of 48 patients with squamocellular carcinoma of the anal canal, who underwent endoscopic US as part of a pre-treatment assessment including endoscopy with biopsy, pelvic magnetic resonance imaging, and total body computed tomography scan. All the tumors were staged with the traditional anal cancer staging system and with a novel US staging. All the patients were treated with definitive chemoradiation and subsequent follow-up. Overall and disease-free survival (DFS), as well as factors influencing survival were analyzed.
Median follow up was 108 mo. American Society of Anesthesiologists score, and US based staging system were related with DFS. By combining these two prognostic variables 4 groups with different prognoses were identified.
A staging system based on tumor invasion is more similar to the staging of all other intestinal cancers and may better reflect a prognostic significance. By combining US staging with other prognostic variables, groups of patients with different prognoses can be determined. In the future the US staging could be introduced as one of the predictive clinical parameters in the setting of anal cancer, in order to improve the prognostic accuracy and possibly implement a tailored therapeutic approach.
Anal cancer is a rare disease and prospective studies are difficult to conduct in a single center. The usefulness of the US staging system, in addition to traditional staging, as prognostic determinants, should be further validated in larger studies in order to plan treatment strategies based on risk categories.