CSCO Colorectal Cancer Diagnosis and Treatment Guidelines Update 2021, one article is cleared!

*Only for medical professionals to read for reference.
This year's Chinese Society of Clinical Oncology (CSCO) Colorectal Cancer Diagnosis and Treatment Guidelines have been adjusted and updated in screening, imaging, pathology and medical treatment.
The main updates are focused on medical treatment and Locally advanced colorectal radiotherapy part.

The CSCO Guidelines Conference held in Beijing on April 23-24 is one of the most important conferences in the field of oncology in China.

At the conference on the 24th, Professor Yuan Ying from the Second Affiliated Hospital of Zhejiang University School of Medicine and Professor Zhang Zhen from Fudan University Cancer Hospital shared the updated key points of internal medicine and radiotherapy in the colorectal cancer diagnosis and treatment guidelines.

Medical treatment: Keeping pace with the times, new everywhere 1 Screening chapter update point 1: In areas where conditions are available, direct colonoscopy (change from level II recommendation to level I recommendation for people at general risk of 50-74 years old), Because the current epidemiological studies show that compared with no screening, colonoscopy screening can reduce the risk of morbidity by 56% and the risk of death by 50%.

Update 2: The addition of "fecal FIT-DNA testing" for screening of general risk populations is a level III recommendation, and for individuals with contraindications to colonoscopy, the addition of "CT colon imaging" is a level III recommendation.

2 In the imaging section, the barium enema has been deleted from the diagnosis table of colon cancer and rectal cancer.

3 In the pathology chapter of metastatic rectal cancer surgery/biopsy specimens, the detection of "RASA and BRAF gene mutations" was changed from level II recommendation to level I recommendation.

4 Chapter of Internal Medicine Treatment The update of internal medicine treatment is the most updated part of this CSCO colorectal cancer diagnosis and treatment guidelines.
The main update content is the treatment of patients with metastatic colorectal cancer (mCRC), which provides you with more treatment decision options.■ Update 1: The status of three-drug chemotherapy is becoming more and more important in the treatment of the potentially resectable group: For patients with wild-type RAS and BRAF, the new level III recommendation of FOLFOXIRI + cetuximab (type 2B evidence) for the potentially resectable group For patients, the goal of treatment is to shrink the tumor in a short-term and quickly, and to create conditions for surgery.
A small sample of research shows that FOLFOXIRI + cetuximab can significantly improve the objective response rate (ORR) of potentially resectable patients, so it is regarded as a level III recommendation Write a guide.

With the gradual increase in the use of three-drug chemotherapy for patients with colorectal cancer in my country, the oncologist’s experience in the use of three-drug chemotherapy and the ability to control adverse reactions have gradually increased.
Therefore, the CSCO guidelines have gradually improved the three-drug chemotherapy since 2019.
The recommended strength of targeting in translational therapy.

However, Professor Yuan Ying also pointed out that when choosing three-drug chemotherapy±targeted therapy, the patient's treatment needs, tumor biological behavior and patient status should be comprehensively considered to determine the patient's final treatment plan.

■ Update 2: Immunotherapy improves the treatment position of patients with high microsatellite instability (MSI-H)/mismatch repair defects (dMMR).
The first-line plan for palliative care: separate MSI-H/dMMR patients and add pembrolizumab Monoclonal antibody as level I recommendation (Class 1A evidence); second-line and third-line palliative care: separate MSI-H/dMMR patients, and PD-1 inhibitors (not limited to specific types) as level II recommendation (Class 2A evidence) .

One of the key points of this guideline update is to separate MSI-H/dMMR patients in the palliative care group.
Because this population receives traditional chemotherapy + targeted therapy (limited ORR), the treatment of MSI-H/dMMR patients is different Other patients can better benefit from immunotherapy.

Studies such as KEYNOTE-177 have shown that patients with MSI-H/dMMR are relatively less sensitive to chemotherapy + targeted therapy.
In order to pursue maximum tumor regression, PD-1 inhibitors can be selected for patients with unresectable metastatic bowel cancer.
Perform conversion therapy. Table 1 Results of the primary endpoint of the KEYNOTE-177 study.
At the same time, in palliative care, patients with MSI-H/dMMR were listed separately, and according to studies such as KEYNOTE-177, in the first-line program of palliative care for patients with MSI-H/dMMR, pembrolizol Monoclonal antibody is used as a level I recommendation (Class 1A evidence); for the second-line and third-line palliative care of MSI-H/dMMR patients, the specific types of PD-1 inhibitors are not emphasized, as a level II recommendation.

Table 2 Recommendations for first-line palliative treatments ■ Update point 3: More options for palliative care Third-line palliative care: Newly added trifluridine tepipyrimidine (TAS-102) + bevacizumab level III recommendation (Class 2B evidence) ) And Cetuximab + Irinotecan (previously received cetuximab treatment) III recommendation (3 types of evidence) based on the results of some small-sample studies, single-arm studies and randomized controlled studies, trifluridine Tepipyrimidine + bevacizumab can help increase the progression-free survival (PFS) and overall survival (OS) of patients with colorectal cancer, but at the same time, attention should be paid to TAS-102 + bevacizumab At the same time, it is necessary to pay attention to the patients' bone marrow toxicity.

Based on the results of the CRICKET small sample study, RAS/BRAF wild-type mCRC patients were treated with cetuximab in the first line, and after receiving chemotherapy + anti-angiogenic drugs in the second line, there were still 20% of patients with cetuximab + irinotecan in the third line.
The ORR and 54% disease control rate (DCR).

Therefore, cetuximab + irinotecan (previously treated with cetuximab) was written into the guideline as a level III recommendation.

It should be noted that before the introduction of cetuximab treatment, circulating tumor DNA (ctDNA) testing still suggests that RAS/BRAF wild-type mCRC patients will benefit more.

■ Update 4: Delete the note about "Capecitabine combined with cetuximab is not recommended for treatment" ■ Update 5: Is the asymptomatic primary tumor of mCRC staying? For the treatment of initial unresectable metastatic colon cancer, a new note is added: "When the metastasis is unresectable, there is still no consensus on whether the asymptomatic primary tumor needs resection and the best resection.

Therefore, it is necessary to make individualized decision-making for each case under the framework of multidisciplinary diagnosis and treatment (MDT).
It is necessary to carefully evaluate the tumor progression rate, estimated survival time, the location and size of the primary tumor, and the circumference of the intestinal cavity/intestinal stenosis The degree, willingness and feasibility of receiving the whole body quality and other factors are integrated to determine whether to remove the primary tumor.
"
Radiation therapy: Based on the "cornerstone", the 2021 version of the CSCO Colorectal Cancer Guidelines for Diagnosis and Treatment of Colorectal Cancer will be updated mainly in radiotherapy.
cT3/T4 N+ (locally advanced) colorectal cancer.

More research reports have emerged in 2020, which provides more help for decision-making in the treatment of cT3/T4 N+ colorectal cancer.

2021 version of CSCO colorectal cancer diagnosis and treatment The guidelines also introduce the decision-making concept of stratified treatment.
It should be noted that for stage II rectal cancer with low local recurrence risk, neoadjuvant radiotherapy can be exempted after multidisciplinary discussion.

The definition of low local recurrence is: tumor stage is cT3a/b N0 and greater than 10cm from the anus, MRI showed that the distance to the mesangial fascia is ≥2mm and there is no
extramural vascular invasion.
The 2021 version of CSCO colorectal cancer diagnosis and treatment guidelines radiotherapy part of cT3/cT4 or N+ rectal cancer treatment updates are as follows: ■ Update 1: The original level I recommendation "Concurrent radiotherapy and chemotherapy + transabdominal resection + adjuvant chemotherapy (Class 1A evidence)" was revised to "synchronous radiotherapy and chemotherapy +/- interval chemotherapy (re-evaluation) + radical resection of rectal cancer + adjuvant chemotherapy (Class 1A evidence)".

Professor Zhang Zhen pointed out: After neoadjuvant chemoradiation and before surgery, patients with rectal cancer have an interval of 6-11 weeks, so that patients can recover from the toxicity of preoperative radiotherapy and chemotherapy and fully shrink the tumor.
.

currently a number of studies have shown that chemotherapy may increase patient for disease control, chemotherapy can be selected intervals:.
FOLFOX, CAPEOX, 5- FU or capecitabine, re-evaluation of MRI before surgery
some patients may take the TNT treatment mode That is, "induction chemotherapy-concurrent radiotherapy-consolidation chemotherapy" to obtain long-term survival benefits.

■ Update 2: For patients who have difficulty in retaining the sphincter, a new program of "enhanced concurrent radiotherapy and chemotherapy (capecitabine combined with irinotecan) (re-evaluation) + radical resection of rectal cancer + adjuvant chemotherapy" ( Level I recommendation) (Class 1B evidence).

■ Update 3: For patients with cT3, any N, MRF+ or cT4, any N, add: Intensified concurrent radiotherapy and chemotherapy (capecitabine combined with irinotecan concurrent radiotherapy and chemotherapy) (reassessment) + radical treatment of rectal cancer Surgery + adjuvant chemotherapy (class 1B evidence); short-term radiotherapy + 12-16 weeks of chemotherapy + radical resection of rectal cancer II recommended level (class 1B evidence) ■ Update 4: In the principle of radiotherapy, the new "sphincter preservation" is added In order to increase tumor regression or watchful waiting strategies, capecitabine combined with irinotecan can be used for simultaneous radiotherapy and chemotherapy.

Combined with irinotecan, the genotyping of UGT1A1*1*1 (6/6 type) is required under the guidance of UGT1A1 genotyping ) Or UGT1A1*1*28 (6/7 type) patients recommend irinotecan doses of 80mg/m2/w and 65mg/m2/w respectively.

Professor Zhang Zhen said: For patients with rectal cancer, the anal organs are currently reserved It has become a research hotspot and most sought-after target for everyone.

Therefore, the 2021 version of the guideline is updated: For patients with difficulty in retaining the sphincter, or for patients with cT3, any N, MRF+ or cT4, the degree of concurrent radiotherapy and chemotherapy can be increased.
The concurrent chemotherapy regimen was adjusted to: the regimen of capecitabine combined with irinotecan can significantly increase the patient’s pathological remission (pCR) rate and DCR.

Alternatively, the treatment strategy (including TNT) of interval chemotherapy after radiotherapy and chemotherapy can be selected as well as The strategy of sequential chemotherapy after short-course radiotherapy to improve the probability of organ preservation.
It
should be pointed out that the order of neoadjuvant treatment prior to radiotherapy and chemotherapy has a higher organ preservation rate.

Summary: The 2021 version of CSCO Colorectal Guidelines is mainly updated in internal medicine.
The content is: a new three-drug combination chemotherapy + targeted therapy is an optional option for conversion therapy; and a separate list of patients with MSI-H/dMMR to make everyone notice that both palliative care and conversion therapy of this type of patients should pay attention to PD- 1 Inhibitor. The updated content of the radiotherapy part is mainly based on the original "German Research" and strengthened in different stages and treatment links, in order to obtain better local control and long-term survival.