Colorectal Cancer - Overview

Summary

This video provides an overview of colorectal cancer, highlighting its prevalence as the second most common cancer, particularly among younger populations due to factors like diet. Key risk factors include age, male sex, smoking, family history, and certain genetic conditions. The clinical presentation varies based on tumor location in the colon, with symptoms ranging from weight loss and anemia to abdominal pain and rectal bleeding. Diagnosis involves a range of tests, including colonoscopy and imaging. Staging is crucial for prognosis, with survival rates varying from 90% for early stages to less than 10% for advanced stages. Treatment typically involves surgery, chemotherapy, and potentially radiotherapy.

Takeaways

• 😀 Colorectal cancer is the second most common cancer and the most common gastrointestinal malignancy.
• 😀 The prevalence of colorectal cancer is rising in younger populations, potentially due to dietary factors.
• 😀 Key risk factors for colorectal cancer include age, male sex, smoking, family history, and diet (high in red meat, low in fiber).
• 😀 Other risk factors include polyposis syndromes (FAP, Lynch disease), inflammatory bowel diseases, and personal history of colon cancer.
• 😀 Symptoms of right-sided colorectal cancer include weight loss, iron deficiency, and a palpable mass in the lower right abdomen.
• 😀 Symptoms of left-sided cancer include blood in stools, abdominal pain, bloating, and changes in bowel habits.
• 😀 Rectal cancer symptoms may include blood on the stool surface and abdominal pain, often with a sensation of incomplete evacuation.
• 😀 The colon has specific blood supply routes, and surgical removal of tumors requires careful consideration of blood flow and lymph drainage.
• 😀 Colon cancer can appear as polypoid, ulcerative, stenosing, or infiltrative tumors, and each form may lead to bowel obstruction.
• 😀 Staging of colorectal cancer includes TNM (tumor, nodes, metastasis) and Duke staging systems, with survival rates varying by stage.
• 😀 Treatment for colorectal cancer includes surgical removal (colectomy), chemotherapy, radiotherapy, and palliative care for advanced cases.

Q & A

What is colorectal cancer, and why is it significant?

Colorectal cancer is the second most commonly diagnosed cancer and the most common gastrointestinal malignancy. Its prevalence is rising, especially among younger populations, potentially due to changes in diet.

What are the main risk factors for developing colorectal cancer?

Risk factors include age, male sex, smoking, family history of colorectal cancer, diet (high in red meat, low in fiber), genetic conditions like FAP and Lynch Syndrome, personal history of polyps, and inflammatory bowel diseases like Crohn's disease and ulcerative colitis.

How do symptoms of colorectal cancer differ based on the tumor's location?

Symptoms depend on where the tumor is located. Right-sided tumors often present with asymptomatic weight loss and anemia. Left-sided tumors cause bloody stools, abdominal pain, bloating, and changes in bowel habits. Rectal tumors can lead to bright red blood on stools and a feeling of incomplete evacuation.

What are the main anatomical features of the colon relevant to colorectal cancer?

The colon has teniae coli, longitudinal smooth muscle ribbons. It is supplied by the inferior mesenteric artery, which branches into smaller arteries that help provide blood to the colon. These features are important for surgical planning and maintaining blood flow during resection.

What are the types of pathological forms of colorectal cancer?

Colorectal cancer can present in various forms, including polypoid, ulcerative, stenosing, and infiltrative types. These forms all eventually lead to some form of obstruction.

What diagnostic tests are performed to detect colorectal cancer?

Diagnostic tests include an abdominal examination, per rectal examination (via proctoscopy), colonoscopy (for visual inspection and biopsy), CT and PET scans for staging, and blood tests like liver function tests (LFTs), full blood count (FBC), and tumor markers such as CEA.

How is colorectal cancer staged, and what are the different stages?

Colorectal cancer is staged using the TNM system, assessing tumor size (T), lymph node involvement (N), and metastasis (M). Another staging method is Duke's staging, which has four stages (0-IV). Stage 0 has a 90% five-year survival, while Stage IV, with metastasis, has less than a 10% survival rate.

What is the role of surgery in treating colorectal cancer?

Surgical treatment for colorectal cancer involves colectomy (removal of part of the colon) and lymphadenectomy (removal of lymph nodes). The type of surgery depends on the tumor's location. Right-sided tumors require right hemicolectomy, left-sided tumors require left hemicolectomy, and rectal tumors may need a high anterior resection or abdominal-perineal resection.

What additional treatments may be used alongside surgery for colorectal cancer?

In addition to surgery, chemotherapy (often using 5-fluorouracil) is commonly administered, and radiotherapy may also be used. These treatments are typically used for advanced cases or when cancer has spread to other parts of the body.

What is palliative care, and when is it used in colorectal cancer management?

Palliative care focuses on symptom management and improving the quality of life for patients with advanced or metastatic colorectal cancer. It is used when the cancer is no longer curable, aiming to alleviate pain and other distressing symptoms.