The clinical features of colorectal carcinoma manifest due to the tumor itself or due to a local and metastatic spread of the tumor. However, it must be remembered that a certain proportion of patients are asymptomatic and are only detected incidentally or during screening. The common clinical manifestations arising from the tumor are rectal bleeding, change in bowel habits, rectal/ abdominal mass, anemia, weight loss, abdominal pain, pelvic pain, and urinary symptoms [1] [2] [3].

Rectal bleeding is a common manifestation. This presents as either drops of fresh blood or as blood streaked on the stools [4]. Dark-colored blood, in general, is more likely to be associated with colorectal cancer than bright red-colored blood [5]. Sometimes, bleeding can occur in an occult fashion without the patient having taken any notice. However, long-term blood loss, even in minute quantities, leads to symptoms of anemia [6].

Change in bowel habits is yet another common symptom. This presents as diarrhea, constipation, a sensation of incomplete evacuation, and tenesmus.

Other symptoms due to a local and metastatic spread of colorectal carcinoma are the pelvic pain, back pain, urinary symptoms, and yellowish discoloration of the sclera.

Related signs that may be identified on general physical examination are cachexia, paleness, and jaundice. Abdominal examination may help in the detection of ascites and hepatomegaly.

Digital rectal examination is the most specific test in physical examination and it may reveal the size of the tumor and features such as ulceration and local spread. It may also reveal a change in anal sphincter tone, which will indicate whether the tumor has spread locally to involve the nerves. Proctoscopy will help to further visualize the tumor.

Screening is an important part of diagnosing colorectal carcinoma and has led to its decline in incidence over time [7]. The recommended mode of screening is colonoscopy every ten years from 50 years of age [8].

The mainstay of diagnosing colorectal carcinoma is colonoscopy followed by biopsy of the suspicious lesions.

Further testing is aimed at grading and staging the tumor that may have an implication on management.

Blood studies such as complete blood count, renal function tests, and hepatic function tests are important too as they serve as indicators of organ damage.

Serum carcinoembryonic antigen (CEA) levels give an insight into prognosis.

Other tests which must be considered are ultrasonography (US) and magnetic resonance imaging (MRI) to assess the spread of the disease.

A chest radiography and abdominal computed tomography (CT) may also help to assess metastatic spread. Positron emission tomography (PET) scans are gaining popularity as an effective imaging modality to detect metastatic lesions.

Molecular genetic testing to detect various genetic mutations is rapidly gaining evidence as a guide for the treatment of metastatic colorectal cancer.

Treatment for colorectal carcinoma depends on the stage of the cancer and the patient's overall health. Common treatment options include surgery, chemotherapy, radiation therapy, and targeted therapy. Surgery is often the primary treatment, especially if the cancer is localized. Chemotherapy and radiation therapy may be used to shrink tumors before surgery or to eliminate remaining cancer cells afterward. Targeted therapy involves drugs that specifically target cancer cell mechanisms.

The prognosis for colorectal carcinoma varies based on several factors, including the stage at diagnosis, the patient's age, and overall health. Early-stage colorectal cancer has a higher chance of successful treatment and survival. The five-year survival rate for localized colorectal cancer is approximately 90%, but this rate decreases if the cancer has spread to other parts of the body. Regular follow-up care is crucial for monitoring and managing any recurrence.

The exact cause of colorectal carcinoma is not fully understood, but several risk factors have been identified. These include age (most cases occur in people over 50), a family history of colorectal cancer, certain genetic syndromes, a diet high in red or processed meats, obesity, smoking, and heavy alcohol use. Chronic inflammatory conditions of the colon, such as ulcerative colitis and Crohn's disease, also increase the risk.

Colorectal carcinoma is one of the most common cancers worldwide, affecting both men and women. It is more prevalent in developed countries, likely due to lifestyle factors such as diet and physical inactivity. The incidence of colorectal cancer increases with age, and it is more common in individuals over 50. However, recent trends show a rise in cases among younger adults, highlighting the need for awareness and early detection.

Colorectal carcinoma typically begins as a benign polyp on the inner lining of the colon or rectum. Over time, genetic mutations can cause these polyps to become cancerous. The progression from a benign polyp to invasive cancer involves multiple genetic changes that affect cell growth and division. As the cancer grows, it can invade nearby tissues and spread to other parts of the body through the lymphatic system or bloodstream.

Preventing colorectal carcinoma involves lifestyle modifications and regular screening. A diet rich in fruits, vegetables, and whole grains, along with regular physical activity, can reduce the risk. Limiting alcohol consumption and avoiding smoking are also important preventive measures. Regular screening, such as colonoscopy, can detect precancerous polyps early, allowing for removal before they develop into cancer.

Colorectal carcinoma is a common and potentially serious cancer that affects the colon and rectum. Early detection through screening and awareness of symptoms can significantly improve outcomes. Treatment options vary based on the stage of the cancer and may include surgery, chemotherapy, and radiation. Understanding risk factors and adopting a healthy lifestyle can help prevent the development of colorectal cancer.

If you or someone you know is experiencing symptoms such as changes in bowel habits, blood in the stool, or unexplained weight loss, it is important to seek medical evaluation. Regular screening is crucial, especially for individuals over 50 or those with a family history of colorectal cancer. Adopting a healthy lifestyle, including a balanced diet and regular exercise, can help reduce the risk of developing colorectal carcinoma.

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