Endoscopic submucosal dissection to treat squamous cell carcinoma in situ of the anal canal

Clinical application of endoscopic submucosal dissection for superficially invasive squamous cell carcinoma/high-grade squamous intraepithelial lesion involving the canal anal

BACKGROUND

Superficially invasive squamous cell carcinoma (SISCC) and high-grade squamous intraepithelial lesions (HSIL) involving the anal canal are rare, and their surgical management involves local excision. Endoscopic submucosal dissection (ESD) has recently emerged as a promising treatment. This study aimed to evaluate the feasibility and safety of ESD for SISCC and HSIL in the anal canal.

METHODS

All patients diagnosed with SISCC or HSIL in the anal canal who underwent ESD between November 2018 and May 2023 were included. Patient age, sex, pathology, human immunodeficiency virus (HIV) status, human papillomavirus (HPV) status, T stage, en bloc rate, and R0 resection rate were analyzed.

RESULTS

Ten patients, including two men and eight women, with a median age of 61 (51-68) years were enrolled. All patients were HIV-negative, but five (50%) were HPV-positive. Pathological examination showed tumor stage of two patients as T2, one as T0 of SISCC, and seven as Tis of HSIL. The median specimen and tumor sizes were 24 (6-65) mm and 18 (6-55) mm, respectively. The en bloc and R0 resection rates were 100% and 80%, respectively. No severe complications occurred and no recurrence was observed at the follow-up (median follow-up period, 9 (1-35) months).

CONCLUSIONS

ESD is a reliable and minimally invasive procedure that enables more individualized treatment options for specific groups. As we were limited by the length of the observation period, the long-term performance of ESD for SISCC and HSIL involving the anal canal requires further investigation.

Endoscopic underwater detection and resection of anal squamous intraepithelial lesions in non-anesthetized patients - a feasibility study and comparison with standard surgical treatment

BACKGROUND

Anal squamous intraepithelial lesions (ASILs) correspond to premalignant changes preceding the development of anal squamous cell carcinoma.

OBJECTIVE

To describe a new endoscopic technique to detect and remove ASILs in non-anesthetized patients and compare it with standard surgical treatment.

METHODS

For endoscopic treatment, high resolution (HR) flexible endoscopes with a distal attachment were used. Underwater inspection of the anal canal was performed in near-focus mode with white light and narrow-band imaging. Detected lesions were resected with a diathermia snare after local injection of xylocaine/adrenaline. We did a retrospective comparison of all patients who underwent endoscopic or standard surgical treatment for ASILs at Ersta hospital in Stockholm between 2018 and 2020. Patient files were reviewed for number of lesions, treatments until macroscopic radicality, degree of dysplasia, bleeding, pain and other complications.

RESULTS

Endoscopic (n = 37) and surgical (n = 43) treatment displayed comparable number of lesions per patient (p = .37). The number of procedures until macroscopic radicality was higher for endoscopy than surgery (p = .04). However, in endoscopic follow up of 12 of the surgically treated patients, residual ASIL was found in 10 cases. Post-procedural bleeding requiring healthcare occurred in two endoscopy patients and one surgically treated patient.

CONCLUSIONS

Underwater resection using a HR flexible endoscope in non-anesthetized is a new, feasible and well tolerated method for ASILs treatment. Its efficacy and risk of complications seem comparable to standard surgical treatment while avoiding general anesthesia. However, minor lesions might be overlooked at surgery.

Safety, feasibility, and short-term-outcome of anal endoscopic submucosal dissection for anal intraepithelial neoplasia: an option for focal lesions?

BACKGROUND

Anal intraepithelial neoplasia (AIN) appears in three different stages. AIN 1 and AIN 2 (p16 negative) are defined as low risk and unlikely to progress to invasive anal cancer. AIN 2 (p16 positive) and AIN 3 are of high risk and should be treated because progression rates to anal cancer are around 10% and treatment significantly reduces this risk. The correct treatment is still a matter of debate. Human papilloma virus (HPV) plays a role in the development of AIN. Our aim was to assess anal endoscopic dissection (aESD) as an intervention for AIN3.

METHODS

We retrospectively evaluated patients who underwent aESD for AIN 3 between December 2017 and March 2023. The interventional technique itself (duration, complications, size of specimen) and patient outcomes (recurrence, progression to anal cancer, re-intervention) were analyzed.

RESULTS

Fifteen patients with a median age of 52 years (23-78) underwent aESD for AIN 3. All tested specimens were positive for HPV. Median duration of intervention was 56.1 min, one delayed postinterventional bleeding occurred, and specimen size was 12.05 cm2. Median follow-up was 11.17 months. Three recurrences (20%) appeared: one was resected via biopsy and two were again treated with aESD. There was no progression to invasive anal cancer in the follow-up period.

CONCLUSIONS

Anal endoscopic submucosal dissection seems to be a safe and feasible treatment for AIN. Recurrences are seldom and can be treated again with the same method. Nevertheless, indications for resection in comparison to radiofrequency ablation, pharmacological therapy, and watch-and-wait strategy are still unclear.

TRIAL REGISTRATION

Ethics commission of Salzburg, Austria, EK-Nr. 1056/2023. Keywords: Endoscopic submucosal dissection, anal intraepithelial neoplasia, anal cancer.