**3. Management of ERC**

### **3.1 The multidisciplinary team (MDT)**

There are significant challenges for the MDT in treating ERC. As the early stage incidence becomes more common, newer treatments and strategies will emerge to address the complexities in balancing outcomes against morbidity. While this may further complicate decisions, fundamentally the MDT relies heavily on macroscopic and radiological features of the ERC. Once a lesion has been determined as malignant, or at least has suspicious morphology at endoscopy, despite limited histological

evidence, the decision on how best to remove it safely must be made. In recognition of these challenges there has been an increase in polyp-focused MDTs, though significant variations in those treatment decisions exist [5].

Any decision relies on accurate delivery of information to the patients to facilitate their own decisions in their shared care. Discussions must include the tumour characteristics, grade and location, as well as patient factors such as age, sex, comorbidities, and performance status. Patients must then be informed of the MDTs discussion as well and address their concerns on stoma rates, recurrence risks and the incidence of post-operative complications.

With the increasing complexity of those decision and number of patients coming through MDTs, protocol tools have attempted to unify standards, but remain far from perfect [8]. A recent Cochrane review in 2017 demonstrated that the use of these tools can improve a patient's knowledge of risk and, interestingly, seems to increase the likelihood of patients choosing less radical surgery [6].

Therefore, decisions require experienced specialists in MDT meetings aided by accurate staging as possible and formal assessment of patient risk. For individual risk assessment for treatment, prediction models are quite common such as p-possum scoring, performance status and ASA scores. More surgery specific models, such as the American College of Surgeons (ACS) surgical risk calculator, are also available, however the evidence for their use to inform patients of outcomes in ERC is limited. Decisions are made avoiding the methodological limitations of these models and once again rely on the experience of the MDT [9, 10].

### **3.2 Options for treating ERC**

As for any rectal cancer, options for ERC treatment must be patient-centred. The initial workup determines tumour stage, location, circumferential resection margins (CRM) margins, and presence or absence of metastatic disease. Patient fitness and preference, alongside the availability of treatment, including available research trials should also be considered by the MDT.

### *3.2.1 Traditional TME surgery*

For many years TME surgery was the only acceptable curative treatment of any rectal cancer, involving either an anterior resection or abdominoperineal resection. This facilitates full staging of local disease postoperatively as lymphadenectomy will guide the need for adjuvant treatment. However, the significant risk, particularly in frail patients, and that of a stoma when fitted to avoid the risks of anastomotic leak, must be considered and discussed with the patient.

Disease recurrence is very much related to tumour grade, accepted as less than 5% with well to moderately differentiated and node negative cancers [11]. Anastomotic leak and significant complication rates vary depending on pelvic factors, patient health, intraoperative findings, tumour height, previous surgery and neoadjuvant treatment but are typically quoted between 4 and 10%.

### *3.2.2 Organ preservation techniques*

Transanal Endoscopic Microsurgery (TEM), Transanal Endoscopic Operations (TEO) & Transanal minimally invasive surgery (TAMIS).

### *Multidisciplinary Management of Early Rectal Cancer DOI: http://dx.doi.org/10.5772/intechopen.106838*

Historically, local excision was only possible under direct vision, using an anal retractor and towards organ preservation. The TEM platform later emerged as forerunner to definitive treatment for ERCs by MIS with no adverse features [39–41]. This approach should only be considered in patients with cT1 disease with no evidence of lymph node involvement [40]. TEM allows for complete local disease control with accurate, local excision. It allows a full-thickness excision of the affected bowel wall and primary closure. For pT1, SM1, node negative ERCs, it offers comparable oncological results as TME surgery, with significantly less morbidity [42]. The recurrence rates of T1 lesions without adverse features vary but are largely agreed to be in the region of 10–15% (see **Table 3**). However, in T2 lesions, also without adverse features, this jumps to 25% [43]. The same study shows little difference in R1 (involved margin) resection rates, around 5%, when compared to traditional TME surgery. Alternative platforms include TEO and, gaining wider popularity, TAMIS (see **Figure 4**). While there is a steep learning curve for all transanal techniques, TAMIS allows transferable skills gained at laparoscopic resections and the outcomes are similar to TEMS [1].

The ongoing advancement of minimally invasive technology is likely to improve the accessibility of ERC surgery. The transference of robotic skills to TAMIS, known as R-TAMIS, promises to aid accurate dissection and better intraluminal control of suturing to close the rectal wall defect. It may allow repair of perforations that breach the peritoneal reflection which occur on resecting anterior lesions and would otherwise have required abdominal (open or laparoscopic) access [1].
