Oftentimes, colon cancer signs are not obvious unless you are actively looking for them. There is a wide range of symptoms associated with the disease, from severe to mild. Understanding the symptoms is important for early detection, so you can work with your doctor to treat the condition.Local symptomsSince these symptoms are so varied, they are generally broken down into two types: local and systemic. Local symptoms affect the colon itself and your bathroom habits. They are more common and easily noticed. Changes in your bowel movements and their frequency is an ordinary symptom. Both constipation and diarrhea are indicators, especially intermittent combinations of both. Very severe symptoms are red or dark reddish-black blotches of blood in your stools, and you should not ignore them. Many of these symptoms often occur in combination with abdominal discomfort, bloating, cramps and excess gas.Systemic symptomsThe second variety of colon cancer symptoms are referred to as systemic. These symptoms affect your entire body and are often harder to interpret. Commonly, unintentional weight loss can occur. Loss of appetite is often experienced with nausea or vomiting. Feeling fatigued even when you have had plenty of rest is also a common symptom. More extreme symptoms cause noticeable physical changes. These include anemia, low red cell count and iron count in your blood and jaundice, yellowing of the skin and whites of the eyes.Do not ignore any type of symptom, whether it is local or systemic; all symptoms are considered serious and warrant medical attention if experienced for prolonged amounts of time. Although colon cancer often creates symptoms, in some cases, people do not experience any symptoms. If you experience any local symptoms for more than a week at a time or any systemic symptoms for more than a few days, contact your doctor immediately. Although not always indicative of colon cancer, these symptoms can result from other serious medical conditions. Work with your doctor closely to determine the cause of any symptoms, and plan a course of treatment.