Can you tell me, are precancerous cells on cervix serious?

Yes: precancerous cells in the cervix represent in situ cells that have not yet invaded the basement membrane to become invasive. Given time this transformation usually via the HPV virus will take place and one then has "Cancer". Precancerous lesions are treated by cryosurgery or a Cone resection where the involved portion of the cervix is wedged out. Later colposcopy and Pap should then be normal.

Possibly: Precancerous cells are also known as "dysplasia" or "squamous intraepithelial lesion". The degree of sil is important in determining outcome. If sil is low grade, it may resolve spontaneously and is often managed conservatively. If sil is high grade, then surgical excision of the area may be needed. Talk with your doc / provider to learn what the best treatment is for you. Hope this helps.