Colorectal Cancer PDF

Colorectal Cancer Treatment Diagnostic criteria Clinical manifestations Pathophysiology  Colorectal Cancer Colorectal cancer is the...

Colorectal Cancer Treatment Diagnostic criteria Clinical manifestations Pathophysiology  Colorectal Cancer Colorectal cancer is the 2nd most common cancer in Australia 5336 deaths caused by colorectal cancer in Australia. Can occur anywhere on the large intestines 90% of cases in adults diagnosed over 50 Tumors are most often of epithelial Fig 1 Distribution of bowel cancer by anatomical site, UK (2007-09) (adapted from Cancer Research UK, bowel cancer incidence statistics, www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/bowel-cancer/incidence) origin Adenoma (benign) Adenocarcinoma (malignant) Development of Colorectal cancer  Causes of Colorectal Cancer Two pathways identified to lead carcinoma development: Series of events triggering chromosomal instability (85%) Loss of tumour suppressor ability Impaired DNA repair Mutations in the APC tumour suppressor gene (adenomatous polyposis coli) lead adenomatous polyp (precursor to malignant tumour) Replication errors (15%) Chromosomes remain intact, defects in DNA repair https://www.nejm.org/doi/full/10.1056/nejmra0804588  Colorectal Cancer Clinical Manifestations Manifestations depend on location and characteristics of the tumor Early stages: asymptomatic Enlargement of tumor: ulceration and hemorrhage Tumor is along ascending colon: occult blood in stool Tumor is along descending colon or rectum: frank blood in stool Abdominal pain Bowel obstruction Anemia: the result of blood loss in the stool Change in bowel habits Common general manifestations are present Paraneoplastic manifestations are present  Colorectal Cancer Diagnostic Criteria History taking, physical examination Blood tests RBC Faecal immunochemical test (FIT) Colonoscopy Barium enema CT or MRI scans PET scan Ultrasound https://www.bowelcanceraustralia.org/tests-investigations#FIT  Colorectal Cancer Treatment Colorectal Cancer Staging stage I (ACPS A) – tumours are found only in the lining of the bowel (early or limited disease) stage II (ACPS B) – tumours have spread deeper into the layers of the bowel walls (locally advanced disease) stage III (ACPS C) – cancer has spread to nearby lymph nodes (locally advanced disease) https://www.bowelcanceraustralia.org/prognosis stage IV (ACPS D) – tumours have spread beyond the bowel to other parts of the body, such as the liver or lungs, or to distant lymph nodes (advanced or metastatic disease). Treatment is dependent on tumour stage and location https://www.pharmacytimes.com/publications/health-system-edition/2020/May2020/early-screening-is-key-in-colorectal-cancer