Sigmoid mass palpable every morning.the physician told me no need to make a colonoscopy cause i am young and this mass could be stool. is that right?

A bit more info: First off: how do you know it's a sigmoid mass? Do you mean left lower quadrant mass? Does it go away ever? The answer to colonoscopic diagnosis depends on your symptoms like constipation, bleeding etc as well as family history. If there's a strong family history of colon CA than a c-scope might be warranted even if you didn't have a palpable mass

How do: you know the mass is related to the sigmoid? There are other potential causes of intraabdominal masses....a sigmoid mass would have to be very large to be palpated. If further work up is warranted, a CT scan may be the next imaging step. Whatever your age, a palpable mass needs to be evaluated.

Maybe...: Your physician may have a point if the mass resolves after your morning bowel movement. However, your concern deserves at the very least a check for blood in your stool, as well as an imaging study of the colon and/or lower abdomen/pelvis. A GI specialist (gastroenterologist) should be happy to assist with these simple assessments, as well as treatment appropriate to your risk factors & findings.