Digestive 
Blood
Cardiovascular
Dermatology
Genitourinary,
Hormones
Infections
Oncology and
Musculo-skeletal
Mental health and
Parasites
Respiratory
Senses
Various
Colorectal cancer usually presents no alarming symptoms in its early stages and the most common can go unnoticed because they are nonspecific and result from other causes.
Some of the most common symptoms are, among others: changes in bowel habits, blood in the stool, abdominal discomfort, or weight loss for no apparent reason.
At the appearance of any of these symptoms, consult a doctor.
