History of the "Pap" smear

When I was a pathology resident in 1982-1986, many pathologists used the classification developed by Papanicolaou consisting of grades 1-5. We were more sophisticated and used the system that included HPV changes, mild dysplasia, moderate dysplasia, severe dysplasia and carcinoma in situ. Of course this terminology was used in biopsy pathology and we tried to correlate them. We spent a lot of time quibbling about whether a particular case was HPV or mild dysplasia and whether another case was severe dysplasia or carcinoma in situ both on biopsies and cytology. At that time, we thought HPV changes were benign viral changes that would regress and dysplasia was the precursor lesion to cervical carcinoma. Eventually it was discovered that HPV was actually the cause of cervical dysplasia. So HPV changes and mild dysplasia were combined into one. A concept was published using the terminology of cervical intraepithelial neoplasia or CIN. It had three levels. CIN I was mild dysplasia including HPV changes; CINII was moderate dysplasia; CINIII included severe dysplasia and carcinoma in situ. So now, there was no more quibbling on the low or the high end of the spectrum. However, a problem still remained especially on cytology: how do we separate the middle grade lesions from the high and low grade ones? What difference did it make? There were several problems. First, pathologists all over the country used different classifications, some using class 1-5, some CIN and some descriptive. There was no uniformity in reporting. There was also lack of inter and intraobserver reproducibility, i.e. today I look at a smear and call it mild dysplasia. Next week I look at the same smear and call it moderate. The question arises as to whether these discrepancies make any difference for the treatment of the patient. At the National Cancer Institute in Bethesda, Maryland a group of experts got together to try and address these issues. In 1988, they published a system of reporting called The Bethesda System. They proposed a two tiered system: low grade squamous intraepithelial lesion (LSIL) and high grade squamous intraepithelial lesion (HSIL). LSIL included HPV changes and mild dysplasia (CINI). HSIL included moderate and severe dysplasia and carcinoma in situ (CINII and CINIII).

Bethesda System

Sometimes things are obvious such as the flowers here in full bloom. Others, such as the buds, are more hidden. Such it is with cervical cancer; sometimes it is hidden from our view until it is too late. Fortunately, we have developed a system of screening to prevent needless deaths.

Introduction

Three Rivers Pathology is a group of local pathologists providing pathology services to Kennewick General Hospital in Kennewick, Washington. We provide complete anatomic pathology services including surgical pathology, cytology and autopsy services. We use SurePath liquid based cytology for both gynecological and non-gynecological cytology specimens and report gyn cytology according to the Bethesda system. We have onsite capability to perform immunohistochemistry on surgical specimens as well as special stains to enhance diagnostic abilities. We are comfortable handling specimens from all body sites and we have additional special expertise in hematopathology and pulmonary and mediastinal pathology.