Transanal Minimally Invasive Surgery (TAMIS): Standardizing a Reproducible Procedure

CLASSICA: Validating artificial intelligence in classifying cancer in real time during surgery

AIM

Treatment pathways for significant rectal polyps differ depending on the underlying pathology, but pre-excision profiling is imperfect. It has been demonstrated that differences in fluorescence perfusion signals following injection of indocyanine green (ICG) can be analysed mathematically and, with the assistance of artificial intelligence (AI), used to classify tumours endoscopically as benign or malignant. This study aims to validate this method of characterization across multiple clinical sites regarding its generalizability, usability and accuracy while developing clinical-grade software to enable it to become a useful method.

METHODS

The CLASSICA study is a prospective, unblinded multicentre European observational study aimed to validate the use of AI analysis of ICG fluorescence for intra-operative tissue characterization. Six hundred patients undergoing transanal endoscopic evaluation of significant rectal polyps and tumours will be enrolled in at least five clinical sites across the European Union over a 4-year period. Video recordings will be analysed regarding dynamic fluorescence patterns centrally as software is developed to enable analysis with automatic classification to happen locally. AI-based classification and subsequently guided intervention will be compared with the current standard of care including biopsies, final specimen pathology and patient outcomes.

DISCUSSION

CLASSICA will validate the use of AI in the analysis of ICG fluorescence for the purposes of classifying significant rectal polyps and tumours endoscopically. Follow-on studies will compare AI-guided targeted biopsy or, indeed, AI characterization alone with traditional biopsy and AI-guided local excision versus traditional excision with regard to marginal clearance and recurrence.

Transanal minimally invasive surgery - A single-center experience

Background

Transanal minimally invasive surgery (TAMIS) was described in the literature 10 years ago. This procedure requires laparoscopic technical skills. It has been well accepted widely worldwide. TAMIS has been applied to multiple procedures, including excision for rectal polyps and cancer, with acceptable outcomes. The study aimed to assess the outcomes of TAMIS in a large district general hospital.

Methodology

A retrospective study on prospectively collected data on 52 consecutive patients of TAMIS performed in a single unit was conducted between May 2014 and February 2020. Data were collected on patient demographics, clinical diagnosis, peri-operative findings, pathological findings, adequacy of excision and complications. Patients were followed up as per the trust and national post-polypectomy guidelines.

Results

Among the 52 patients, TAMIS procedures were completed in 50 patients, of which 31 were female. The procedure was successful in 96.5% but had to abandon in two cases. There was no conversion to another procedure. Pre-operative indications were rectal polyps and one case was an emergency TAMIS in a patient who was bleeding following incomplete colonoscopic polypectomy. The final histology reported that the majority were benign polyps (46), and only 11 cases were malignant. The median distance of the lesion from the anal verge was 6 cm (3-10 cm). The median operative time was 55 min (8-175 min). A total of 45 (77.5%) lesions were completely excised and had negative microscopic margins. Most patients (64%) were discharged home the same day. No complications were observed at a median follow-up of 20 months (6-48 months). There was no mortality.

Conclusions

Our data suggest that TAMIS can be safely performed in a district general hospital for both benign and early rectal cancer. TAMIS was also able to control post-polypectomy bleeding and completion of rectal polypectomy. In selected cases, day-case TAMIS is safe and feasible.

Transanal Minimally-Invasive Surgery (TAMIS): Experience with No Closure of the Rectal Defect

Background In transanal minimally-invasive surgery (TAMIS), the closure of the rectal defect is controversial, and endoluminal suture is one of the most challenging aspects. The goal of the present study is to evaluate the short- and medium-term complications of a consecutive series of patients with extraperitoneal rectal injuries who underwent TAMIS without closure of the rectal defect.

Materials and Methods A prospective, longitudinal, descriptive study conducted between August 2013 and July 2019 in which all patients with extraperitoneal rectal lesions, who were operated on using the TAMIS technique, were consecutively included. The lesions were: benign lesions ≥ 3 cm; neuroendocrine tumors ≤ 2 cm; adenocarcinomas in stage T1N0; and adenocarcinomas in stage T2N0, with high surgical risk, or with the patients reluctant to undergo radical surgery, and others with doubts about complete remission after the neoadjuvant therapy. Bleeding, infectious complications, rectal stenosis, perforations, and death were evaluated.

Results A total of 35 patients were treated using TAMIS without closure of the defect. The average size of the lesions was of 3.68 ± 2.1 cm (95% confidence interval [95%CI]: 0.7 cm to 9 cm), their average distance from the anal margin was of 5.7 ± 1.48 cm, and the average operative time was of 39.2 ± 20.5 minutes, with a minimum postoperative follow-up of 1 year. As for the pathologies, they were: 15 adenomas; 3 carcinoid tumors; and 17 adenocarcinomas. In all cases, the rectal defect was left open.

The overall morbidity was of 14.2%. Two patients (grade II in the Clavien-Dindo classification) were readmitted for pain treatment, and three patients (grade III in the Clavien-Dindo classification) were assisted due to postoperative bleeding, one of whom required reoperation.

Conclusion The TAMIS technique without closure of the rectal defect yields good results, and present a high feasibility and low complication rate.

Transanal minimally invasive surgery using laparoscopic instruments of the rectum: A review

Transanal minimally invasive surgery (TAMIS) was first described in 2010 as an alternative to transanal endoscopic microsurgery (TEM). The TAMIS technique can be access to the proximal and mid-rectum for resection of benign and early-stage malignant rectal lesions and also used for noncurative intent surgery of more advanced lesions in patients who are not candidates for radical surgery. TAMIS has a shorter learning curve, reduced device setup time, flexibility in instrument use, and versatility in application than TEM. Also, TAMIS shows similar results in a view of the operation time, conversion rate, reoperation rate, and complication to TEM. For these reasons, TAMIS is an easily accessible, technically feasible, and cost-effective alternative to TEM. Overall, TAMIS has enabled the performance of high-quality local excision of rectal lesions by many colorectal surgeons. As TAMIS becomes more broadly utilized such as pelvic abscess drainage, rectal stenosis, and treatment of anastomotic dehiscence, the acquisition of appropriate training must be ensured, and the continued assessment and assurance of outcome must be maintained.

Computer Vision in the Surgical Operating Room

Background

Multiple types of surgical cameras are used in modern surgical practice and provide a rich visual signal that is used by surgeons to visualize the clinical site and make clinical decisions. This signal can also be used by artificial intelligence (AI) methods to provide support in identifying instruments, structures, or activities both in real-time during procedures and postoperatively for analytics and understanding of surgical processes.

Summary

In this paper, we provide a succinct perspective on the use of AI and especially computer vision to power solutions for the surgical operating room (OR). The synergy between data availability and technical advances in computational power and AI methodology has led to rapid developments in the field and promising advances.

Key Messages

With the increasing availability of surgical video sources and the convergence of technologies around video storage, processing, and understanding, we believe clinical solutions and products leveraging vision are going to become an important component of modern surgical capabilities. However, both technical and clinical challenges remain to be overcome to efficiently make use of vision-based approaches into the clinic.

Cost Effectiveness of Endoscopic Resection vs Transanal Resection of Complex Benign Rectal Polyps

BACKGROUND & AIMS

Complex benign rectal polyps can be managed with transanal surgery or with endoscopic resection (ER). Though the complication rate after ER is lower than transanal surgery, recurrence is higher. Patients lost to follow up after ER might therefore be at increased risk for rectal cancer. We evaluated the costs, benefits, and cost effectiveness of ER compared to 2 surgical techniques for removing complex rectal polyps, using a 50-year time horizon-this allowed us to capture rates of cancer development among patients lost from follow-up surveillance.

METHODS

We created a Markov model to simulate the lifetime outcomes and costs of ER, transanal endoscopic microsurgery (TEM), and transanal minimally invasive surgery (TAMIS) for the management of a complex benign rectal polyp. We assessed the effect of surveillance by allowing a portion of the patients to be lost to follow up. We calculated the cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio or each intervention over a 50-year time horizon.

RESULTS

We found that TEM was slightly more effective than TAMIS and ER (TEM, 19.54 QALYs; TAMIS, 19.53 QALYs; and ER, 19.53 QALYs), but ER had a lower lifetime discounted cost (ER cost $7161, TEM cost $10,459, and TAMIS cost $11,253). TEM was not cost effective compared to ER, with an incremental cost-effectiveness ratio of $485,333/QALY. TAMIS was dominated by TEM. TEM became cost effective when the mortality from ER exceeded 0.63%, or if the loss to follow up rate exceeded 25.5%.

CONCLUSIONS

Using a Markov model, we found that ER, TEM, and TAMIS have similar effectiveness, but ER is less expensive, in management of benign rectal polyps. As the rate of loss to follow up increases, transanal surgery becomes more effective relative to ER.

Cirugía mínimamente invasiva transanal (TAMIS): técnica y resultados de la experiencia inicial

Antecedentes: la cirugía transanal endoscópica es un abordaje mínimamente invasivo recientemente descrito, que provee una exposición superior y permite el acceso a las lesiones del recto en toda su extensión. Además, provee un riesgo menor de compromiso de los márgenes de resección, menores tasas de recurrencia y una menor morbimortalidad en comparación con la escisión transanal convencional o las remociones endoscópicas. Objetivos: se pretende describir la experiencia inicial y los resultados con la cirugía transanal mínimamente invasiva (transanal minimally invasive surgery, TAMIS) en términos de resecciones completas y posibles complicaciones relacionadas con el procedimiento. Materiales y métodos: esta una serie de casos con un seguimiento prospectivo de los pacientes con TAMIS. Se analizaron los resultados de 27 pacientes intervenidos en varios centros de Medellín, Colombia, entre enero de 2012 y diciembre de 2016, realizados con cirugía laparoscópica monopuerto (single-port laparoscopic surgery, SILS) (21 casos) o el GelPOINT® Path (6 casos), junto con el apoyo de la óptica del laparoscopio (16 pacientes) y del endoscopio flexible (11 pacientes). Resultados: se realizaron 27 TAMIS en el mismo número de pacientes, 10 mujeres (37 %) y 17 hombres fueron evaluados. Se realizó un seguimiento a los pacientes durante aproximadamente 12 meses, en promedio 32 meses. La edad promedio fue de 68 años (52-83 años). El tamaño promedio del tumor fue de 5,3 cm (2-9 cm) y la distancia promedio desde el margen anal fue de 7 cm (5-9 cm) Las complicaciones posoperatorias se dieron en 6 casos (22 %) Una perforación rectal se corrigió por vía laparoscópica en el mismo acto quirúrgico y otra por la misma vía transanal. Una estenosis rectal se manejó con dilatación digital, y hubo un caso de sangrado rectal menor, uno de retención urinaria y un paciente presentó un cáncer rectal avanzado a los tres meses de la resección con margen microscópico positivo (4 %). No hubo reingresos. La mortalidad por la intervención fue nula. La patología operatoria reportó la presencia de adenoma de bajo grado en 3 casos (11 %), de alto grado en 11 (41 %), adenocarcinoma in situ en 6 (22 %), tumor neuroendocrino en 5 pacientes (18 %), 1 caso de fibrosis cicatricial (4 %) y 1 de leiomioma (4 %). Limitaciones: los resultados no son extrapolables a la población general debido al poco número de intervenciones y la ejecución limitada a solo dos autores. Conclusiones: en nuestra experiencia inicial, TAMIS es un procedimiento mínimamente invasivo con una baja morbilidad posoperatoria, es curativa para lesiones benignas y para pacientes seleccionados con cáncer temprano.

Rectal MRI for Cancer Staging and Surveillance

MRI is an integral part of the multidisciplinary treatment of rectal adenocarcinoma. Staging MRI is performed to establish TNM stage and assess for prognostic factors, including circumferential resection margin status and presence of extramural vascular invasion. The results of staging MRI determine which patients will undergo preoperative neoadjuvant chemoradiation before resection. Restaging MRI is performed to evaluate for treatment response and may identify patients with no residual visible tumor who are candidates for a "watch and wait" strategy in lieu of resection. In addition, the results of MRI in conjunction with endoscopy determine the surgical technique used to remove the tumor.

Transanal minimally invasive surgery for local excision of early rectal tumor

INTRODUCTION

Local excision (LE) is used in early rectal cancer and other pathologies for diagnostic purposes and curative treatment, as well as for palliative surgery in patients who are medically unfit for radical resection. Recently, transanal minimally invasive surgery (TAMIS) has been increasingly accepted as a means for performing LE. Here, we present a TAMIS technique for LE to which endoscopic submucosal dissection was applied.

MATERIALS AND SURGICAL TECHNIQUE

We used conventional laparoscopic instruments, including a 10-mm 30° camera. A GelPOINT Path® was introduced into the anal canal to maintain stable pneumorectum and valve-free access. After injecting MucoUp® (SI-4404) into the submucosal layer at the edge of the tumor, we marked dots on the mucosa with cautery using the point of the monopolar diathermy L-hook; we then performed circumferential mucosal incision and submucosal dissection. The remaining defects do not always have to be sutured.

DISCUSSION

TAMIS for LE was performed for seven patients with no postoperative complication and mortality. One lesion required full-thickness resection, one lesion required partial full-thickness resection, and five lesions were dissected completely beneath the submucosal layer. Based on the pathological results, three patients underwent conventional radical resections. One patient had local recurrence at the 8-month follow-up and underwent endoscopic mucosal resection. TAMIS may be a promising option for LE that provides acceptable oncological outcomes and benefits to quality of life.

Transanal minimally invasive surgery for benign large rectal polyps and early malignant rectal cancers: experience and outcomes from the first Canadian centre to adopt the technique

BACKGROUND

Transanal minimally invasive surgery (TAMIS) has emerged as a relatively new technique in treating early cancer and benign lesion of the rectum. The technique is likely to be widely adopted, surpassing other comparable techniques owing to its simple setup and cost-effectiveness. We assessed the outcomes of TAMIS at our centre.

METHODS

We retrospectively reviewed prospectively collected data on 50 patients who underwent TAMIS for benign, malignant T1 or T2 cancers that were unfit for radical surgery over a 4-year period. Outcomes, including 30-day complications and recurrence, as well as our ability to implement and integrate this technique at our centre were assessed.

RESULTS

All 50 TAMIS procedures were successful. The average lesion was 7 cm from the anal verge, the average tumour size was 2.5 cm, the average duration of surgery was 73 minutes, the average length of stay was 1.1 days, and the margin negativity was 84%. Major indications in our series included 25 lesions that were too large for endoscopic resection, 14 early cancers or high-grade dysplasia, 10 margin checks postpolypectomy, 6 cases of recurrent polyposis, and 4 medically unfit patients. There were no deaths. The rate of short-term complications, including rectal bleeding, reoperation and urinary retention, was 16%. The rate of long-term complications, including anal incontinence and stenosis, was 4%. Benign and malignant recurrence rates were 2% and 6%, respectively. Overall long-term requirement for invasive procedures, low anterior resection or abdominoperineal resection, was 12%.

CONCLUSION

To our knowledge, this is the first Canadian study showing TAMIS to be an efficient and safe procedure for the treatment of well-selected patients with rectal lesions. Outcomes from our centre are comparable with those found in the literature.

Recent advances in the management of rectal cancer: No surgery, minimal surgery or minimally invasive surgery

Over the last decade, with the acceptance of the need for improvements in the outcome of patients affected with rectal cancer, there has been a significant increase in the literature regarding treatment options available to patients affected by this disease. That treatment related decisions should be made at a high volume multidisciplinary tumor board, after pre-operative rectal magnetic resonance imaging and the importance of total mesorectal excision (TME) are accepted standard of care. More controversial is the emerging role for watchful waiting rather than radical surgery in complete pathologic responders, which may be appropriate in 20% of patients. Patients with early T1 rectal cancers and favorable pathologic features can be cured with local excision only, with transanal minimal invasive surgery (TAMIS) because of its versatility and almost universal availability of the necessary equipment and skillset in the average laparoscopic surgeon, emerging as the leading option. Recent trials have raised concerns about the oncologic outcomes of the standard “top-down” TME hence transanal TME (TaTME “bottom-up”) approach has gained popularity as an alternative. The challenges are many, with a dearth of evidence of the oncologic superiority in the long-term for any given option. However, this review highlights recent advances in the role of chemoradiation only for complete pathologic responders, TAMIS for highly selected early rectal cancer patients and TaTME as options to improve cure rates whilst maintaining quality of life in these patients, while we await the results of further definitive trials being currently conducted.

Transanal Minimally Invasive Surgery for Rectal Lesions

Background and Objectives:

Transanal minimally invasive surgery (TAMIS) has emerged as an alternative to transanal endoscopic microsurgery (TEM). The authors report their experience with TAMIS for the treatment of mid and high rectal tumors.

Methods:

From November 2011 through May 2016, 31 patients (21 females, 68%), with a median age of 65 years who underwent single-port TAMIS were prospectively enrolled. Mean distance from the anal verge of the rectal tumors was 9.5 cm. Seventeen patients presented with T1 cancer, 10 with large adenoma, 2 with gastrointestinal stromal tumor (GIST) and 2 with carcinoid tumor. Data concerning demographics, operative procedure and pathologic results were analyzed.

Results:

TAMIS was successfully completed in all cases. In 4 (13%) TAMIS was converted to standard Park's transanal technique. Median postoperative stay was 3 days. The overall complication rate was 9.6%, including 1 urinary tract infection, 1 subcutaneous emphysema, and 1 hemorrhoidal thrombosis. TAMIS allowed an R0 resection in 96.8% of cases (30/31 cases) and a single case of local recurrence after a large adenoma resection was encountered.

Conclusion:

TAMIS is a safe technique, with a short learning curve for laparoscopic surgeons already proficient in single-port procedures, and provides effective oncological outcomes compared to other techniques.

Indications and Outcomes From 32 Consecutive Patients for the Treatment of Rectal Lesions by Transanal Minimally Invasive Surgery

BACKGROUND

The aim of this study was to evaluate the feasibility, safety, perioperative morbidity, and short-term outcomes of the transanal minimally invasive surgery (TAMIS) technique.

METHODS

This is a descriptive review of prospectively collected data from 32 consecutive patients who underwent TAMIS procedures in our colorectal unit over a 40-month period. GelPOINT Path port was used in all cases. Demographic data, indications, tumor characteristics, morbidity, and follow-up data were collected. Primary endpoints included feasibility, safety, perioperative morbidity, and resection quality.

RESULTS

Fifteen adenomas, 12 carcinomas, 1 gastrointestinal stromal tumor, and 1 neuroendocrine tumor were locally excised. Additionally, 3 pelvic abscesses were drained transanally using the TAMIS port. Mean distance from the anal verge was 5.6 ± 1.5 cm. Early postoperative complications occurred in 22%, with only one case of major complication (3.1%) requiring reoperation, and no postoperative mortality. Four carcinomas were understaged (33.3%) and 1 adenoma overstaged (6.7%) preoperatively. Three carcinomas were not suspected preoperatively (25%). Microscopic positive lateral margin was found in one case, and no affected deep margin was found. Fragmentation rate was 6.9%, 2 cases, both lesions over 20 cm². In cases of fit patients with high-risk carcinomas, 2 underwent immediate salvage surgery and another 2 refused and were treated with adjuvant radiotherapy. With a median follow-up of 26 months, the overall recurrence rate was 10.3%, 1 adenoma and 2 carcinomas.

CONCLUSION

TAMIS seems to be a safe and reproducible procedure for local excision of well-selected rectal lesions with low morbidity and good functional outcomes.

Urethral Reconstruction with Rectal Mucosa Graft Onlay: A Novel, Minimally Invasive Technique

PURPOSE

Alternative grafts are needed for patients who are not suitable candidates for oral mucosa graft harvest or who have a paucity of oral mucosa graft available for reconstruction. Circumferential colonic mucosal grafts have demonstrated feasibility for urethral reconstruction, although sigmoid resection has been required for graft retrieval. We report the feasibility and short-term outcomes of urethral reconstruction using a rectal mucosa graft harvested by a novel, minimally invasive, transanal endoscopic microsurgical technique.

MATERIALS AND METHODS

We retrospectively reviewed the records of all patients who underwent transanal endoscopic microsurgical rectal mucosa graft harvest and onlay urethroplasty since the technique was first implemented in 2013. Graft failure was defined as inability to pass a 16Fr cystoscope in the grafted urethra.

RESULTS

All 4 strictures were bulbopendulous with a median length of 13.5 cm (range 10 to 21). Median followup was 18 months (range 12 to 28). Stricture etiology was lichen sclerosus in 3 patients and failed hypospadias interventions in 1. Three patients had undergone at least 1 prior urethroplasty. In 1 patient stricture recurred in the graft 10 months following reconstruction. There were no colorectal complications.

CONCLUSIONS

To our knowledge this is the first study demonstrating urethral reconstruction using a rectal mucosa graft harvested by the transanal endoscopic microsurgical technique. Initial data revealed that this technique is feasible and safe, and minimizes graft harvest morbidity. Transanal endoscopic microsurgical harvest of a rectal mucosa graft may provide an alternative graft material for patients with long segment urethral strictures who are not candidates for oral mucosa graft harvest. Further experience and longer followup are needed to validate these findings.

A critical appraisal of transanal minimally invasive surgery (TAMIS) in the treatment of rectal adenoma: a 4-year experience with 51 cases

OBJECTIVE

The aim of this study was to describe feasibility, postoperative morbidity, and histological outcome of transanal minimally-invasive surgery (TAMIS) in patients with rectal adenoma.

MATERIAL AND METHODS

All patients who underwent TAMIS at a single institution from December 2011 to December 2015 were retrospectively included in the study. Feasibility was based on tumor size, distance of tumor from the anal verge, operative time, and hospital stay. Thirty-day morbidity was defined by the revised Accordion Classification system. Histological outcome included microscopic resection margin status, specimen fragmentation status, and grading of dysplasia in rectal adenoma.

RESULTS

A total of 51 patients with rectal adenoma underwent TAMIS. The median tumor diameter was 32 (4-60) mm and the median distance from the anal verge 8 (3-14) cm. Median operative time was 40 (13-116) min and median length of hospital stay was 1 (0-25) days. Overall morbidity was 12% (four grade 1, one grade 2, and one grade 3 complications). 22% had a positive resection margin, whereas 31% had an indefinable resection margin status mostly due to tissue fragmentation. Median follow-up time was 7 (0-40) months.

CONCLUSIONS

TAMIS is a challenging surgical technique for treatment of rectal adenoma. Our initial experience among 51 patients resulted in a high proportion of positive resection margins and a high fragmentation rate. The role of TAMIS in the treatment of rectal adenoma is to be defined through comparative studies.

Feasibility of the TAMIS technique for redo pelvic surgery

AIM

The aim of this study was to report on the feasibility of transanal minimally invasive surgery (TAMIS) as a novel approach to redo colorectal or ileoanal anastomoses.

METHODS

From October 2014, a prospective institutional database was created for all consecutive patients who underwent redo surgery by TAMIS for presacral sinus or anastomotic stenosis after low anterior resection or pouch-related problems following restorative proctocolectomy. Intra-operative feasibility, 30-day postoperative outcomes, intestinal continuity and complications after 6-month follow-up were evaluated.

RESULTS

Of 17 included patients, 14 underwent anastomotic reconstruction and three completion proctectomy. The median operation time was 265 min (range 201-413). A successful rendezvous with simultaneous transabdominal access was achieved in 15 patients, and the procedure was completed by TAMIS alone in two. Five patients were readmitted within 30 days (29 %). Two (14 %) patients developed an anastomotic leakage within 30 days and 4 (24 %) developed a pelvic abscess requiring reintervention. One patient developed an urethra stenosis and was managed with a suprapubic catheter. Median follow-up was 9 (6-15) months. Within 6-month follow-up, the redo-TAMIS 1 patient developed a delayed anastomotic leak and 1 patient had a recurrent presacral abscess after stoma closure. Intestinal continuity was reached in 71 % of the patients at 6-month follow-up.

CONCLUSION

TAMIS is a valuable approach in redo pelvic surgery, but is still associated with high complication rates related to the complexity of the underlying problem.