Diagnosis of Stage III Colon Cancer

Tanios Bekaii-Saab, MD, FACP:This was in November of 2012. The patient is a 51-year-old man who was referred by his private care physician to gastroenterology for a routine screening colonoscopy. One thing that was noticed in the family history of the patient is that on his father’s side, there was a history of pancreas cancer and his aunt had breast cancer. So, there was some family history of cancer. Colonoscopy was performed and it revealed a 3-cm mass, approximately to the hepatic flexure—so on the right side. A biopsy of that lesion confirmed it was adenocarcinoma, which is consistent with colon primary. At the time, the patient underwent right hemicolectomy, which revealed a moderately differentiated tumor. It was a T3 tumor in terms of the pathological classification. About 15 lymph nodes were removed and they were all cancer-free. So, the patient was T3 and 0, and previous workup showed no evidence of metastatic disease. The appropriate decision was not to proceed with any further adjuvant therapy. The patient recovered really well after the surgery and is doing well.

The guidelines, for patients at low risk to develop colon cancer, remain that the first colonoscopy has to happen at age 50. Depending on, again, the presence or absence of polyps that are high-risk than the varied interval, the next colonoscopy for most folks would be at 5 or 10 years. In fact, 10 years is very acceptable. That’s for the colonoscopy. It is also acceptable to have a blood stool test with sigmoidoscopy, Cologuard, and other tests as potential alternatives for those who may not want to consider a colonoscopy. However, the gold standard in the United States remains a colonoscopy at age 50 for all patients with a low risk. Now, history of previous cancer certainly raises a red flag, and that’s something that needs to be discussed with the family physician.

Now clearly a history of colon cancer or high-risk polyps would warrant an earlier colonoscopy, depending on the age. So, if the patient’s, let’s say, father had colon cancer or a high-risk polyp at age 75, the guidelines may remain the same—meaning at 50, you start your colonoscopy. However, if a father, a mother, or a first-degree relative had their cancer at age 45, then the first colonoscopy had to be in an interval of 10 years or even earlier than the diagnosis, meaning at 35 or younger for the first colonoscopy. In this situation, in this particular patient, it’s difficult to understand whether the family had some genetic screening, which most folks at that time did not have any form of genetic screening, and whether that would have warranted an earlier colonoscopy.

So, surgery was appropriate in this patient with a small tumor. Lymph node harvest is important, and the guidelines refer to at least 12 lymph nodes that have to be removed to do adequate staging—10 to 12 lymph nodes, but conservative 12 nodes. This patient had 15 lymph nodes removed, so I think we can consider the staging appropriate. And why is this important? If we have more than 12 lymph nodes that are negative, that places the patient at a definite stage 2, and a stage 2, especially lower risk like this patient, essentially does not warrant adjuvant chemotherapy. If the lymph node harvest was lower than that, let’s say 8 or 9 lymph nodes, then there will be a big question mark about the quality of the lymph node harvest. And by default, we give those patients the benefit of the doubt and will treat them with adjuvant therapy, and most of them unnecessarily. So, it’s very important, and I’ve seen this happening less and less and less, thankfully. The guidelines have been very adamant about the lymph node harvest—12 lymph nodes are a must for those patients.

Transcript edited for clarity.

November 2012

• A 51-year-old man was referred to gastroenterology for screening colonoscopy.
• Family history includes pancreatic cancer on his father’s side and pre-menopausal breast cancer in his aunt.
• Colonoscopy revealed a 3-cm mass, proximal to the hepatic flexure.
• Biopsy confirmed the lesion to be of adenocarcinoma histology.
• At the time, the patient underwent right hemicolectomy revealing a moderately differentiated tumor. Fifteen lymph nodes were removed and tested negative for metastatic disease, denoting stage T3N0M0 colon cancer.
• The patient healed without complications and received no further treatment.

April 2015

• The patient continued to feel well, except for occasional fatigue and diarrhea.
• Routine evaluation showed elevated carcinoembryonic antigen.
• PET/CT scan revealed several small lesions in multiple lobes of the liver that were PET avid
• Biopsy was performed and confirmed the liver lesions to be metastases from colon cancer
• The patient was referred to a local oncologist and started on infusional 5-FU and oxaliplatin (FOLFOX) in combination with bevacizumab.
• CT scan 2 months after starting treatment showed a partial response to therapy; at 4 months the patients tumor continued to shrink
• Oxaliplatin was discontinued; subsequently the patient received maintenance therapy with capecitabine and bevacizumab, resulting in continued disease control

February 27, 2017

• The patient has had stable disease for 22 months and remains on bevacizumab maintenance therapy.
• He appears generally well and free of symptoms.