Recent advances in multidisciplinary approach for rectal cancer.

Surgery is a major treatment option for rectal cancer, and total mesorectal excision has been demonstrated to be advantageous in terms of oncological outcome and thus has been the standard surgical approach. Radiotherapy before or after radical surgery is the optimal treatment to control local recurrence of advanced rectal cancer. To date, in many countries, the combination of neoadjuvant concurrent chemotherapy and radiotherapy is considered the standard therapy. A more recent interest in neoadjuvant therapy has been the use of oxaliplatin or targeted agents for neoadjuvant chemoradiotherapy. However, despite many trials of oxaliplatin and targeted agents, 5-FU-based concurrent chemoradiotherapy has remained the only standard treatment option. Postoperative adjuvant chemotherapy with neoadjuvant chemoradiotherapy or induction chemotherapy with neoadjuvant chemoradiotherapy may further improve patient survival, as some clinical studies recently indicated. In Japan, neoadjuvant therapy is not the standard treatment method, because surgery with lateral lymph node dissection is usually performed and this type of surgery may reduce recurrence rate as does radiation therapy. The phase III study to evaluate the oncological effect of the Japanese standard operation (mesorectal excision, ME) with lateral lymph node dissection in comparison with ME alone for clinical stage II and III lower rectal cancer is currently ongoing.