Impact of technology on indications and limitations for transanal surgical removal of rectal neoplasms

Role of minimally invasive surgery for rectal cancer

Rectal cancer is one of the most common malignancies worldwide. Surgical resection for rectal cancer usually requires a proctectomy with respective lymphadenectomy (total mesorectal excision). This has traditionally been performed transabdominally through an open incision. Over the last thirty years, minimally invasive surgery platforms have rapidly evolved with the goal to accomplish the same quality rectal resection through a less invasive approach. There are currently three resective modalities that complement the traditional open operation: (1) Laparoscopic surgery; (2) Robotic surgery; and (3) Transanal total mesorectal excision. In addition, there are several platforms to carry out transluminal local excisions (without lymphadenectomy). Evidence on the various modalities is of mixed to moderate quality. It is unreasonable to expect a randomized comparison of all options in a single trial. This review aims at reviewing in detail the various techniques in regard to intra-/perioperative benchmarks, recovery and complications, oncological and functional outcomes.

A systematic review of local excision followed by adjuvant therapy in early rectal cancer: are pT1 tumours the limit?

AIM

Total mesorectal excision remains the cornerstone of treatment for rectal cancer. Significant morbidity means local excision may be more appropriate in selected patients. Adjuvant therapy reduces local recurrence and improves survival; however, there is a paucity of data on its impact following local excision, which this systematic review aims to address.

METHODS

A systematic search of the MEDLINE, Embase and Cochrane databases using validated terms for rectal cancer, adjuvant therapy and local excision was performed. Included studies focused on local excision with adjuvant therapy for adenocarcinoma of the rectum. Primary outcome measures were local recurrence, survival and morbidity. Studies providing neoadjuvant therapy or local excision alone were excluded.

RESULTS

Twenty-two studies described 804 patients. Indications for local excision included favourable histology, patient choice and comorbidities. T1, T2 and T3 tumours accounted for 35.1%, 58.0% and 6.9% of cases, respectively. The most frequent local excision technique was transanal excision (77.7%). Adjuvant therapy included long-course chemoradiation or radiotherapy. Median follow-up was 51 months (range 1-165). The pooled local recurrence was 5.8% (95% CI 3.0-9.5) for pT1, 13.8% (95% CI 10.1-17.9) for pT2 and 33.7% (95% CI 19.2-50.1) for pT3 tumours. The overall median disease-free survival was 88% (range 50%-100%) with a pooled overall morbidity of 15.1% (95% CI 11.0-18.7).

CONCLUSIONS

This area remains highly relevant to modern clinical practice. The data suggest that local excision followed by adjuvant therapy can achieve acceptable long-term outcomes in high-risk pT1 tumours, but not in T2 tumours and above in whom radical surgery should be offered.