Colon cancer is a common malignant tumor in the gastrointestinal tract and is collectively known as colorectal cancer or colorectal cancer together with rectal cancer. The incidence rate of colorectal cancer in China is increasing year by year and has risen to the third place, only after lung cancer and breast cancer, which is a major disease that seriously threatens human life and health. The incidence of colon cancer is related to genetic factors, colonic adenoma, polyposis, chronic inflammation, less fiber and high fat diet. Compared with rectal cancer, colon cancer is more insidious and not easily detected at an early stage.
I. Clinical manifestations
1. Change in stool characteristics and habits: diarrhea and constipation may occur, or both may alternate. Sometimes mucus or pus-blood stool, accompanied by abdominal discomfort, abdominal pain, abdominal distension and other symptoms.
2, abdominal masses.
3.Intestinal obstruction: there may be manifestations of incomplete or complete intestinal obstruction such as paroxysmal abdominal pain, abdominal distension, absence of stool and anal exhaustion.
4.Unexplained weight loss, emaciation, anemia.
5.Other late manifestations: such as epigastric discomfort, ascites, bone pain, etc.
II. Examination
1.Fiber colonoscopy. It is the main examination means of colon cancer, and can be diagnosed clearly through biopsy.
2.Barium enema. Barium enema cannot obtain pathological diagnosis, but can help to understand the lesion site.
3.Imaging examination such as ultrasound, CT, MRI can understand the size, invasion and metastasis of tumor. PET-CT examination is feasible for those who have economic conditions.
4.Tumor marker examination. Mainly CEA (carcinoembryonic antigen) and CA19-9, which are important reference indicators for colon cancer.
5.Other examinations. Such as stool routine and fecal occult blood examination.
Treatment
1.Surgical treatment
Surgery is the main treatment for colon cancer, mainly applicable to non-advanced patients (some isolated liver metastases and lung metastases can also be treated surgically or after chemotherapy and then surgically).
2.Chemotherapy
It is divided into preoperative adjuvant chemotherapy, postoperative adjuvant chemotherapy and palliative chemotherapy.
(1) Pre-operative chemotherapy (neoadjuvant chemotherapy): It refers to 2-4 cycles (courses) of chemotherapy before surgery, with the purpose of shrinking the tumor, facilitating surgical resection and reducing surgical trauma, as well as reducing the staging of the original inoperable cases to the operable ones. A regimen of fluorouracil plus calcium folinate or fluorouracil plus oxaliplatin is generally used.
(2) Postoperative adjuvant chemotherapy: It refers to the killing of possible residual tumor cells after surgery to prevent tumor recurrence and metastasis. It is usually performed for 6-12 cycles (depending on the regimen). Oxaliplatin plus fluorouracil, or fluorouracil plus irinotecan regimens are generally used.
(3) Palliative chemotherapy: advanced inoperable patients or those with recurrent metastases after surgery, with the aim of prolonging the patient’s survival and providing quality of life. The number of courses of treatment depends on the patient’s condition and the effectiveness of chemotherapy. Chemotherapy regimens such as fluorouracil plus oxaliplatin, fluorouracil plus irinotecan, or siroda monotherapy or tegeo monotherapy can be used.
3.Radiotherapy
There are postoperative adjuvant radiotherapy and palliative radiotherapy.
Postoperative adjuvant radiotherapy: the purpose is to prevent postoperative recurrence and specialization and improve the cure rate.
Palliative radiotherapy: the purpose is to relieve symptoms, prolong life and improve the quality of survival.
4.Molecular targeted therapy
Molecular targeted therapy is a new development in the field of tumor treatment in recent years, which is suitable for advanced colon cancer and postoperative recurrence and metastasis, and can be used alone or in combination with chemotherapy to prolong patients’ survival and improve the quality of survival. There is no evidence yet that it can be used for postoperative adjuvant therapy. Commonly used drugs include cetuximab (Epiduo) and bevacizumab (Avastin), etc.
5. Other treatments.
Including immunotherapy, herbal treatment, etc., which may have some adjuvant effect on colon cancer.