Cancer of the rectum is a common disease. It affects nearly 15,000 new people each year, with more men (53%) than women (47%).
In more than 9 out of 10 cases, it occurs after 50 years. Three types of treatments are used to treat rectal cancer: surgery, radiotherapy and drug treatments.
The standard treatment for Locally Advanced Rectal Cancers (LARC) is multidisciplinary, combining chemotherapy, radiotherapy and surgery. The usual treatment in this situation is called induction chemotherapy administrated before radiochemotherapy. This phase of treatment taking place before surgery is called neoadjuvant therapy.
However, treating all cancers of the locally advanced rectum with the same neoadjuvant treatment exposes patients who are good responders to neoadjuvant chemotherapy with possible toxicity to radiotherapy and patients who are poor responders to ineffectiveness of conventional radiotherapy with surgery and so to a mutilating ineffective treatment.
The short- and long-term toxicity of pelvic radiation may be the most compelling reason to reconsider reflexive neoadjuvant radiochemotherapy (NA-RCT) and to move toward a more individualized approach.
A large North American trial is currently evaluating the suppression of preoperative radiation therapy in patients selected as a good responder to induction chemotherapy.
A first trial called GRECCAR-4 (Surgical Research Group on Rectum CAncer) with induction chemotherapy by 5 Fluorouracil + Irinotecan + Oxaliplatin and personalized radiochemotherapy reported the following results:
- High-dose induction chemotherapy is well tolerated and reproducible
- Early assessment after neo-adjuvant chemotherapy makes it possible to discriminate between good and bad responders without a negative impact on surgery.
- Personalized management of LARC according to the early tumor response to chemotherapy is possible.
- In good responder patients, a resection rate of 100% was achieved (even in the arm without radiotherapy), but due to poor recruitment, it is not possible to draw a formal conclusion regarding these promising results.
- The oncological results at 5 years show a local recurrence rate of 0% for the good responders and 4.8% for the poor responders. The 5-year overall survival was 86.7% with a 5-year progression-free survival of 75.0%.
GRECCAR 14 is the only French trial to question the feasibility of appropriate management of non-metastatic LARC. Its main objective is to evaluate, in good responder patients, personalized management after preoperative CT treatment.
GRECCAR-14 will try to confirm this strategy taking into account the 1st results of GRECCAR 4.
The study will initially focus on 200 patients to assess the surgical quality of this therapeutic strategy and then on 230 additional patients to assess the effectiveness of this personalized treatment on survival without recurrence.