Management of Colorectal Carcinoma
Management Colorectal Carcinoma is extensive surgical resection of the lesion and regional lymphatic drainage. Resection of the primary cancer is still indicated even after metastases. Therefore, open the abdomen and explored for metastases. The goal of colon carcinoma therapy is to remove cancer and lymphovascular supply. 

The intestine resection depends on the blood vessels that drain the cancerous part. Supporting tissues (such as omentum) should be resected en bloc together with cancer. If the entire tumor cannot be removed, palliative therapy is necessary. The anastomosis is performed starting by intestinal irrigation with normal saline solution or povidone-iodine to the lumen's tumor cells can be removed.

The presence of synchronous cancer or adenoma and a family history of Colon Cancer indicates the entire colon is at risk for carcinoma (field defect). Therefore, subtotal or total colectomy is necessary. Synchronous cancer is the presence of more than two cancers simultaneously. A metachronous tumor (new resection in previously resected patients) is also treated similarly.

If finding unpredictable metastases during laparotomy, the primary tumor should be resected and perform the anastomosis. For nonresectable cancer, perform a palliative procedure and create a proximal stoma or bypass.

Stage 0 (Tis, N0, M0)
Polyps contain carcinoma in situ / high-grade dysplasia, which does not risk lymph node metastasis. However, high-grade dysplasia increases the risk of invasive carcinoma. For this reason, excise the polyp completely, and its boundaries should be free of dysplasia. Also, completely remove stemmed polyps endoscopically. At this stage, regular colonoscopy ensures that polyps do not recur and form invasive carcinoma. If the polyp cannot be removed entirely, do a segmental resection.

Stage I: Malignant Polyp (T1, N0, M0)
The management of this stage is based on the risk of recurrence and metastasis to the lymph nodes. Metastases to the lymph nodes are based on the extent of the polyp invasion. In lymphovascular invasion, perform segmental colectomy on poorly differentiated histology.

Stages I and II: Localized Colon Carcinoma (T1-3, N0, M0)
Surgical resection can cure the majority of stages 1 and 2 cases. Some stage 1 cases with complete resection can progress to local or distant recurrences, and chemotherapy does not improve these patients' survival. As many as 46% of stage II patients with complete resection are at death risk. Therefore, adjuvant chemotherapy is recommended for some patients (young and high-risk).

Stage III: Lymph Node Metastasis (T any, N1, M0)
Lymph node involvement is a high risk of recurrence. Therefore, routine chemotherapy adjuvant stage III is recommended. The regimen used for chemotherapy is 5- Fluorouracil with levamisole or leucovorin. To reduce recurrences and increase survival rates. New chemotherapy agents include capecitabine, irinotecan, oxaliplatin, angiogenesis inhibitors, and immunotherapy.

Stage IV: Distant Metastasis (T any, N any, M1)
The survival rate is low at this stage. In patients with systemic disease, 15% of cancer will metastasize to the liver. At this stage, as much as 20% of the potential for resection to heal. The survival rate for these resected patients is higher than not resected. All patients required adjuvant chemotherapy. If the patient cannot be operated on, then do palliative therapy. Palliative therapy used is stenting for obstructive left colon lesions.

Colorectal resection
Colorectal resection is performed under various conditions, including neoplasms (benign and malignant), inflammatory bowel disease, and other cases.

In general, proximal mesenteric ligation eliminates blood flow to the larger part of the colon and require colectomy. Curative resection of colorectal carcinoma is achieved by ligation of the proximal mesenteric vessels and radical cleansing of the mesenteric lymph nodes. In benign process resection, mesenteric resection is not required, and the omentum can be preserved.

Emergency resection
Use emergency resection in obstruction, perforation, and bleeding cases. In this state, no need for bowel preparation, and the patient's condition is unstable. In transverse proximal or right colon resection, ileocolonic anesthesia may be performed.

Laparoscopic resection
The advantages of a laparoscopic are good cosmetically, reduce postoperative pain, and faster bowel recovery. Laparoscopic resection of the large intestine takes longer than open surgery.

 The anastomosis can be formed through 2 intestinal segments. The technique used can be hand sewn or stapled. Types of anastomosis:

1. End to end
Performed when two intestinal segments of the same caliber. This technique is mainly performed on rectal resection. But, it can be used in a colostomy or the small intestine's anastomosis.
2. End to side
Use it when one part of the intestine is larger than the other. This technique is performed in chronic obstruction.
3. Side to end
Performed when the proximal intestine is smaller than the distal part.
4. Side to side
Perform when there is continuity between 2 blood vessels or intestinal segments where the last place has been closed.

The End colostomy is often used rather than loop colostomy. A colostomy is made on the left side of the colon. A defect in the abdominal wall is created, and the colon's end is mobilized through the opening. The distal intestine is expelled through the abdominal wall as a mucus fistula or inside the abdomen as Hartmann's pouch.
Colostomy closure requires a laparotomy. The stoma is dissected from the abdominal wall and identifies the distal intestine, then anastomoses end to end. Complications of necrosis can occur in the early postoperative period due to blood supply disruption. Retraction may also occur, but a colostomy is less of a risk.