45 year old gentleman was diagnosed with right colon cancer (poorly differentiated adenocarcinoma) and solitary metastasis to liver. He underwent a one stage surgery (right hemicolectomy for colon cancer and resection of liver metastasis). The surgery was followed by multiple cycles of chemotherapy. A chemoport was placed for the same. The patient lived for 4 years after diagnosis of advanced poorly differentiated colon cancer.
Multidisciplinary cancer care involves aggressive chemotherapy in the postoperative period (known as adjuvant treatment) or to downstage the disease (inoperable & / or unresectable disease to operable & resectable disease – neoadjuvant treatment) before any surgery. A chemoport (surgery) is inserted for delivering the chemotherapy to avoid problems of venous access. In neoadjuvant setting, chemotherapy is followed by a curative surgery where possible. Surgery is again followed by multiple cycles & lines (1st line, 2nd line etcetera) of chemotherapy. It is especially useful in young &/or fit patients with aggressive cancer disease. These patients can withstand the demanding nature of this treatment regime and may have better survival.
Colon / rectal cancer is one of the commonest form of gastrointestinal cancers. The presentation depends upon which the part of colon (large intestine) is affected. In case of the right colon, the presentation can be abdominal pain, melena, abdominal lump, weight loss, bloating, anemia, acute intestinal obstruction or rarely appendicitis. Sometimes patients present with advanced form of disease like spread to liver, lungs or ascites due to peritoneal deposits. The disease is seen to be more aggressive, mucin secreting, signet ring type and poorly differentiated when it develops at a younger age. Such disease has poorer prognosis / long term survival too. Left colon cancer is discussed elsewhere.
Patients diagnosed or suspected to have a colon / rectal cancer are subjected to multiple tests. The most important ones are checking serum tumor marker CEA (carcinoembryonic antigen), colonoscopy and biopsy, CT scan of abdomen & pelvis and sometimes a PET CT study. The CEA is useful in diagnosing cancer and also to follow treatment response (surgery or chemotherapy). However all patients may not have a raised CEA. CT / PET-CT is done to see if tumor can be operated and removed or has it spread beyond the intestine in the surrounding area or distant organs like liver, lungs etcetera. A colonoscopy ( endoscopy of large intestine to visualize it from within) helps to take a biopsy and also checks whether cancer is in only one part or multiple parts of colon (synchronous primary tumor). The biopsy sample is run through many tests apart from regular histopathology. This includes immunohistochemistry (IHC), genetic tests for mutations (KRAS, BRAF, microsatellite instability) etcetera. These tests help in deciding prognosis, treatment plan treatment sequence, chemotherapeutic drugs to be used. In short have a major impact on treatment. However they are very expensive too.
Patients who have a localized disease undergo a curative colonic resection (right or left hemicolectomy / sigmoid colectomy / anterior resection depending on which part of colon involved ). The surgery is performed as an open or laparoscopic surgery depending on the expertise available, extent of nodal disease and surrounding organ involvement / the bulkiness of tumor and patient presentation. Patients presenting with intestinal obstruction may need an emergency surgery, which may end in doing an ileostomy / colostomy (exteriorization of unobstructed part of small intestine or colon as a temporary or permanent measure). Patients presenting with spread disease benefit with initial chemotherapy as mentioned before and it is later followed by a curative surgery where feasible. This is further followed by chemotherapy.
The patients are later followed on OPD basis initially every 3 months with CEA and USG report. A CT scan and colonoscopy is done once a year. The frequency of investigations and follow up is reduced after 2 years.