According to the cancer registry of Casablanca region, the total number of new cases of rectal cancer recorded during the study period (2013-2017) amounted to 846, representing 3.4% of all registered cases [3]. The number of diagnosed cases doubles every decade for patients aged between 40 and 70 for both sexes [4].

Environmental and dietary factors explain the geographical distribution of colorectal cancer (CRC), with high-risk areas including Australia, North America, Western European countries, and Japan [5]. Smoking, chronic alcoholism, a sedentary lifestyle, and obesity are risk factors for the development of CRC and contribute to the formation of advanced adenomas in young individuals. Some studies estimate that 25% of current CRC cases could have been prevented by recognizing family history as a risk factor and initiating high-risk screening [6].

Rectal bleeding and rectal syndrome are the main symptoms of rectal cancer [7]. Digital rectal examination allows access to tumors located in the lower and middle rectum. This clinical evaluation is crucial for establishing a plan for radical or conservative treatment [8].

Rectoscopy with biopsy allows for a definitive diagnosis [9]. A systematic staging is performed to evaluate the extension of the tumor locally, regionally, and distantly, as well as to search for other synchronous primary lesions [10]. This staging is based on a complete clinical examination [11], pelvic MRI, thoraco-abdominal CT with contrast injection, and colonoscopy to search associated lesions [12]. If there is doubt about hepatic lesions on the CT scan, a hepatic MRI with diffusion sequences can better characterize these lesions [13].

A high preoperative level of tumor markers, particularly CEA and CA 19.9, is associated with a poor prognosis [14]. All of these clinical and paraclinical elements allow the classification of the tumor according to the current standard, which is the 8th edition of the Union for International Cancer Control (UICC) classification [15].

This step is followed by an assessment of the patient's operability and surgical risks. It is recommended to refer to the American Society of Anesthesiology (ASA) classification [16].

The therapeutic management of rectal cancer is multidisciplinary, with surgery being the mainstay. A collaboration between the different healthcare professionals involved leads to an improvement in the quality of the treatement [17]. The decision on the therapeutic approach for each patient should be made in a multidisciplinary team meeting.

The goal of neoadjuvant treatment is to reduce the tumor size, leading to a downstaging of rectal cancer, thereby increasing the resectability rate and decreasing the recurrence rate [18]. Radiotherapy has demonstrated a significant effect on reducing local recurrences by nearly 50%. A Swedish study highlighted an increase in overall five-year survival from 48% to 58% [19]. Chemotherapy administered concomitantly with radiotherapy significantly reduces the risk of local recurrence. Various agents and therapeutic regimens are used, either as neoadjuvant treatment in combination with radiotherapy and/or as adjuvant treatment [20].

However, surgery remains the standard treatment for rectal cancer. The type of surgical resection depends on several key factors, including the tumor's location relative to the anal margin and the locoregional extent on MRI [21]. Lower rectal cancers exhibit distal parietal extension beyond the tumor's inferior pole, corresponding to a submucosal tumor extension or tumor emboli of 1 cm, and rarely exceed this distance. Therefore, a distal resection margin of 1 to 2 cm is sufficient [22]. Total mesorectal excision, performed under direct vision without any manual dissection, has improved oncological outcomes by significantly reducing the local recurrence rate.

Several types of anastomoses can be performed depending on various factors, particularly the type of resection. These anastomoses should preferably be protected by an ileostomy, especially in the case of sub-Douglas (subperitoneal) anastomoses, with continuity restoration 4-6 weeks later.

The presence of lymph node metastases is a significant prognostic factor for recurrence and survival [23]. It is necessary to histologically examine at least 12 lymph nodes to properly stage the tumor [24]. Surgical advances have reduced postoperative mortality from 10% to 2% and local recurrence rates from 30-40% to less than 15% [25]. This rate is also affected by the type of surgical intervention. Mortality is lower after anterior resection compared to abdominoperineal amputation (APA) and is decreased after curative resection versus palliative surgery [26].

Intraoperative complications are more often related to hemorrhage from an injury to the presacral venous plexus during posterior rectal dissection, highlighting the importance of extrafascial dissection while respecting the rectal fascia [27]. Ureteral injuries, with an incidence ranging from 0.1% to 4.5%, commonly occur at the level of the pelvic ureter and are more frequent during abdominoperineal amputations.

Immediate complications of rectal resection surgery primarily include anastomotic leaks in the form of fistulas managed by drainage, pelvic abscesses (localized peritonitis), or generalized peritonitis. Functional urinary and sexual complications, related to hypogastric nerve plexus injury, may also occur [28]. Post-anastomotic stenoses are uncommon, particularly with manual anastomosis. They can result from a previous fistula or tumor recurrence. A biopsy at the anastomosis site is essential to differentiate between the two.

Risk factors for recurrence include a positive circumferential resection margin, extramural vascular invasion, lower rectal tumors, and the absence of neoadjuvant treatment. The challenge of rectal cancer has long been the high rate of local recurrences, estimated at 32% [29]. However, since the advent of neoadjuvant therapies and total mesorectal excision, local recurrences have significantly decreased to currently around 4-8%. Thus, an increase in CEA levels during follow-up may indicate a recurrence, and pelvic MRI with diffusion sequences offers better performance for detecting these tumor recurrences.