Reproductive Pathology I Case Studies


CASE 4: CIN III


Clinical History:

A 38 year-old woman was found to have highly atypical cells on a routine Pap smear. Her family physician obtains a Pap smear from her each year. She was referred to a gynecologist, who performed a colposcopically directed biopsy of the cervix. The biopsy showed CIN III (severe dysplasia). Because the dysplastic-appearing epithelium involved the endocervical canal and its deep border within the canal could not be visualized, a cone biopsy was proposed. However, after further discussion with her physician, the patient decided to have a vaginal hysterectomy.

Image 4.1:

The Pap smear is shown here.

Image 4.2 to 4.4:

Sections of the cervix are shown. Identify squamous metaplasia, severe dysplasia, and carcinoma-in-situ.

Answers:

  1. Has the patient been having yearly Pap smears?

    2. The development of dysplasia to this degree would take several years. It is obvious that the patient has not been having yearly Pap smears. There is up to a 4% false negative rate for each Pap smear, but with yearly Pap smears, the chance of missing a significant lesion is low.

  2. Is there stromal invasion?

    3. Endocervical glands are involved by squamous metaplasia, but there is no evidence of stromal invasion by the CIN process.

  3. What is the diagnosis?

    4. Much of the surface epithelium shows severe dysplasia; however, there are a few areas that could be called carcinoma in situ. This distinction is somewhat subjective, and different pathologists may have slightly varying criteria for making this division. The concept of cervical intraepithelial neoplasia, Grade III (CIN III) is useful because severe dysplasia and carcinoma in situ, which are treated clinically in the same manner, are included in the same category. The patient is cured with excision of the lesion.

  4. What is the natural history of this process?

    5. The process often starts with human papillomavirus (HPV) infection. There is a natural history starting with squamous metaplasia with progression to dysplasia of worsening degree, then carcinoma in situ, then invasive carcinoma. This takes more than a decade.