We have reported about the primary tumor resection for incurable Stage IV colorectal cancer as a multicenter observational study in 2012. Compared with open surgery, laparoscopic primary tumor resection has advantages in the short-term and no disadvantages in the long-term [47]. A systematic review about laparoscopic surgery for Stage IV colorectal cancer also followed this conclusion [48].

It can be said that a laparoscopic operation for overweight patients is a very good indication. The abdominal wall destruction compared with laparotomy is much less in overweight patients, and it can be said that overweight patients receive more merit than thin patients. However, keeping a satisfactory observation field is difficult in overweight patients, and fat adherence of peritoneal caviity is often seen in overweight patients. So high-level surgical technique is often needed. Obesity is reported to be associated with increased conversion rate, operating time, and postoperative morbidity but not to affect surgical safety or oncological security [49, 50].

The patients with transverse colon cancer had been excluded from previous big trials [38–41]; therefore, it remains unclear if the results for colon cancer are similar even in transverse colon cancer. Surgical management for transverse colon cancer has several difficulties. There are various procedures according to the location or stage of tumor: right hemicolectomy, transverse colectomy, or left hemicolectomy. The running of blood vessels of transverse colon has anatomically some variations. Preservation of the pancreas and spleen is needed during the procedure. Therefore, more detailed technique by skilled surgeons is said to be needed for transverse colon cancer surgery.

A previous systematic review of five comparative observational studies reported that the laparoscopic surgery for transverse colon cancer is a safe and effective technique [51]. Although there was a significant increase in operative time in laparoscopic surgery compared with open surgery, less blood loss and faster recovery were seen with laparoscopic surgery.

In regard to the laparoscopic surgery in elderly patients, there had been a fear that the pneumoperitoneum, the surgical position, and longer anesthesia time might affect their cardiopulmonary function after surgery. However, a Japanese large cohort study evaluating the feasibility of laparoscopic procedure for colorectal cancer patients aged 80 years or older reported that the laparoscopic surgery was associated with fewer morbidities and shorter hospital stay than was the open procedure [52]. The authors have also suggested that elderly patients with colon cancer may receive greater benefits from laparoscopic surgery because there is a linear correlation between increasing age and the frequency of postoperative morbidities, such as respiratory, cardiovascular, and neurological complications. Similarly, some observational studies comparing the short-term benefit between laparoscopic surgeries for elderly and younger colorectal cancer patients have proposed that the laparoscopic procedure for elderly patients may have the equal advantage to or greater than that for younger patients [53–57].

It was reported that postoperative urinary and sexual dysfunction can be reduced with careful autonomic nerve preservation [58].

In 2012, we reported a paper about sexual dysfunction after laparoscopic total mesorectal excision (LTME). This indicated that the evaluation of nerve injury by using video reviews would be effective [59].

The laparoscopic surgery provided a magnified view of the pelvis which improved the visualization of constructions than the open surgery. Therefore, the surgery could preserve autonomic nerves more safely. A systematic review showed the following results [60]. The evaluation of urinary function was performed variously, but the included studies reported no significant differences in urinary function after TME between laparoscopic surgery group and open surgery group. As for sexual function, there was also no significant difference in the rate of overall sexual dysfunction between both groups.

In short, the question of whether laparoscopic surgery for rectal surgery would offer improved genitourinary outcomes over open surgery remains unanswered at present.

TAMIS (transanal minimally invasive surgery) was started as a treatment for early rectal cancers and spread widely. Since TAMIS was applied to total mesorectal excision (TME) for advanced rectal cancers, transanal laparoscopic surgery such as TAMIS-ISR (intersphincteric resection) or TAMIS-APR (abdominoperineal resection) has just been beginning to be performed [37, 61, 62].

Single-incision laparoscopic colectomy (SILC) was first reported in 2008 [63]. In this method, all surgical procedures are performed through the umbilicus, which is natural orifice located at the middle of the abdomen and could obscure the operative scar. Main advantage of SILC is considered to be cosmetic [64]. Many reports have been published and suggested the equivalence or superiority in short-term outcomes and the safety of SILC compared with multi-incision laparoscopic colectomy [65–68]. However, many of the previous reports are case reports/series or retrospective studies, and long-term outcomes of SILC are still unclear [67]. Difficulties with scissoring and interference between instruments also exist in SILC surgery, and internal and external conflictions between instruments made it difficult to achieve ideal traction. It might be overcome with new instruments and scopes in the future. Further prospective studies and enough experience of laparoscopic surgery are needed to perform SILC as a standard treatment.

In 2010, robot-assisted surgery for colorectal cancer was first reported in Japan. It has been increasing rapidly despite that it is an uninsured care.

Although robot-assisted surgery for colorectal cancer is a medical treatment not covered by insurance, it may have some advantages that we can operate finely for rectal cancer very close to the anal. However, robot-assisted surgery for colon cancer has not shown clear advantage over laparoscopic colonic surgery. We introduce the robot-assisted surgery only to the rectal cancer patients who want to receive it [69, 70].

Both operation and chemotherapy for colorectal cancer have made remarkable progress over the last decades. Colorectal cancer had been previously associated with a poor prognosis because of anticancer drug resistance and intensive surgical care which often needed blood transfusions and caused high incidence of dysuria. However, colorectal cancer now has a good chance of being cured with improved quality of life by research-validated effective drugs and precise surgical care with a focus on preserving function.

So far, progress in laparoscopic surgery has resulted in evolution of colorectal surgery. Many innovative surgical instruments have been developed and will be developed in the future. However, to achieve higher quality of colorectal surgery, it is essential for surgeons to master basic surgical techniques, understand surgical anatomy, and grasp new procedures and those concepts. A combination of great knowledge and skilled technique with novel devices will lead to an excellent outcome for colorectal cancer patients.