Negative for intraepithelial lesion or malignancy (NILM) means that no pre-cancerous or cancerous cells were seen in your Pap smear. It is a normal result.
The cervix is part of the female genital tract. It is found at the bottom of the uterus where it forms an opening into the endometrial cavity. The narrow passage that runs through the cervix from the vagina to the tissue lining the inside of the uterus is called the endocervical canal.
The part of the cervix inside the vagina is called the exocervix. It is covered by special cells called squamous cells. These cells form a barrier called the epithelium that protects the cervix. The endocervical canal is covered by different kinds of cells that connect to form endocervical glands. The area of the cervix where the exocervix meets the endocervical canal is called the transformation zone. Most cancers of the cervix start in the transformation zone.
The diagnosis of NILM is made after a Pap smear is examined under the microscope by a laboratory technologist (cytotechnologist) or a pathologist. The smear will often show a variety of normal cells, such as squamous cells, endocervical cells, and metaplastic cells. In order to make this diagnosis, the Pap smear must include a sufficient number of squamous cells. The presence of cells from the transformation zone (endocervical or metaplastic cells) is used as a quality indicator but is not required to be present in every sample. Occasionally infectious elements (yeast, bacteria, and viruses) or normal cells shedding from the lining of the uterus (endometrium) may be present on the Pap smear.
NILM is a normal result and most women can continue to be screened at regular intervals. The interval may vary based on your age and the result of an additional test for human papillomavirus (HPV), the virus responsible for increasing your risk for cervical cancer. Talk to your doctor about the screening interval that is right for you.