<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have reecently been diagosed with a pelvic cyst the measurement of 3.5cm, I was told a tumor marker was done and is awaiting results, but ive had this unbelievably striking pain in my lower belly and pelvic area going round my back for nearly 10weeks now ..  <response>: Hi.3.5 cm cyst can not cause any pain in the lower abdomen as you have. The other causes can be - PID-Pelvic Inflammatory Disease, Salpingitis, Enteritis and so on. Since you have not given a detailed history I would suggest you the following:Consult a General Surgeon for a clinical examination get the blood, urine and stool tested. Ulrasonograpgraphy must have been done already. IF you have other symptoms please give feedback to the Surgeon so that he can find a probable cause and treat you accordingly. Small ovarian cyst do not cause pain unless they are twisted, a condition called torsion. 