Colon and prostate cancers are two types of common cancers detected in the elderly individuals. Both cancers are very invasive. These two cancers types are very different from each other, which are discussed below in detail, highlighting the clinical features, symptoms, causes, investigation and diagnosis, prognosis, and the course of treatment of colon and prostate cancers.
Colon Cancer
Large bowel is medically known as the colon. The colon consists of the caecum, ascending colon, transverse colon, descending colon and sigmoid colon. The sigmoid colon is continuous with the rectum. Cancers can manifest themselves at any site, but lower colon and rectum are more frequently affected compared to the upper colon. Colon cancers present with bleeding via rectum, feeling of incomplete evacuation, alternative constipation and diarrhea. There may be associated systemic features such as lethargy, wasting, loss of appetite, and loss of weight.
There are many risk factors for colon cancers. Inflammatory bowel diseases (IBD) lead to cancer due to a high rate of cell division and repair. Genetics play a key role in carcinogenesis because with rapid cell division the chance of cancer gene activation is high. First degree relatives with colon cancers suggest a significantly higher chance of getting colon cancers. There are genes called proto-oncogenes, which result in malignancies if a genetic abnormality transforms them into oncogenes.
When a patient presents with colon cancer symptoms, a sigmoidoscopy or colonoscopy is indicated. Using the scope, a small piece of the growth is removed to be studied under the microscope. Cancer spread should be assessed to decide on treatment methods. Imaging studies like magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound scans help assess the local and distant spread. Other routine investigations should also be done in order to assess the fitness for surgery and other relevant factors. Full blood count may show anemia. Serum electrolytes, blood sugar levels, liver and renal function should be optimized before surgical procedures. There are special tumor markers that be used to detect the presence of a colorectal cancer. Carcinoembryonic antigen is one such investigation.
Most of the colon cancers are adenocarcinomas. Colon cancers are preventable. High intake of fruits and vegetables, low intake of red meat, and regular physical activity significantly reduce the colorectal cancer risk. Aspirin, celecoxib, calcium and vitamin D reduce the colorectal cancer risk. Familial adenomatous polyposis increases the risk of colon cancer. Flexible sigmoidoscopy is a reliable investigation to screen for suspicious lesions in the colon. For localized cancers, the curative treatment option is complete surgical resection with adequate margins to either side of the lesion. Localized resection of a large bowel segment can be done via laparoscopy and laparotomy. If the cancer has infiltrated lymph nodes, chemotherapy increases life expectancy. Fluorouracil and Oxaliplatin are two commonly used chemotherapeutic agents. Radiation is also of significant benefit in advanced disease.
Prostate Cancer
Prostate cancers occur in the elderly individuals. They present with obstructive urinary symptoms; difficulty to start a urine stream, poor urine stream, and prolonged dribbling after urination. Many cases are detected incidentally during a digital rectal examination. During digital rectal examination, the prostate feels lumpy, enlarged without the median groove. Prostate cancers are slow growing mostly.
Once detected, prostate specific antigen, ultrasound scan of the pelvis (trans-rectal) may be performed. Sometimes a CT scan or an MRI may be needed to assess the spread. Biopsy of suspicious lesions is an option. If detected, transurethral resection of prostate or open surgery is available treatment options. Post-surgically, radiotherapy and chemotherapy also play a role. Because prostate cancer is testosterone sensitive, a bilateral orchiectomy is also an option for advanced disease.
What is the difference between Colon Cancer and Prostate Cancer?
• Colon cancer is a bowel cancer while prostate cancer is a genitourinary cancer.
• Colon cancer occurs both in males and females while prostate cancer occurs in males only.
• Colon cancers are common from 35 above while prostate cancers are common above 55 years of age.
• Colon cancers present with bowel features while prostate cancers present with urinary features.
• Colon cancers produce CEA while prostate cancers produce PSA.
• There are classifications for both cancers and treatment options depend on the stage of the disease.
Further Readings:
1. Difference Between Pancreatic Cancer and Pancreatitis
2. Difference Between Hemorrhoids and Colon Cancer
3. Difference Between Cervical and Ovarian Cancer
4. Difference Between Bone Cancer and Leukemia
5. Difference Between Adenocarcinoma and Squamous Cell Carcinoma