Cervical Cytology Practice Guideline
Approved by the ASC Executive Board November 10, 2000
VI. Cervical Cytology Reporting
VI.A. Specimen Description/Clinical Information
The final report should include the information provided on the requisition such as the menstrual status and any previous history that places the patient in the high-risk category (e.g. history of abnormal cytology results or biopsies, history of cancer). History from the clinician regarding contraception, exposure to exogenous hormones, chemotherapy, or radiation therapy is also important for proper interpretation of cytologic findings. Incorporating the given clinical history in the report assists the clinician in correlating cytologic and clinical findings.
VI.B. Reporting of Specimen Adequacy and Cytologic Findings
The Bethesda System (TBS) of cervical cytology reporting, developed at the 1988 NCI workshop and updated in 1991, was formulated as a means to help standardize the communication of cervical cytology diagnoses.77 TBS reports have three basic components: a descriptive interpretation, a statement of specimen adequacy, and, optionally, a general categorization of the interpretation. In addition, laboratory and hospital accreditation groups (CAP,78 JCAHO79) have also imposed general requirements on all laboratory reports. Federal regulations require the use of narrative descriptive nomenclature, but do not specify the use of any particular reporting system. Most laboratories use TBS or a modification of it for reporting cervical cytology results.80
The adequacy statement of TBS was developed as a standardized means of communicating the quality of the specimen. The statements “satisfactory for evaluation”, “satisfactory but limited by” and “unsatisfactory” indicate whether or not the specimen is likely to be sufficient to fulfill the test’s screening purpose. The number of cells, cell composition and ability to clearly visualize the cells are factors that are considered in assessing adequacy and are specified in TBS. The statement “satisfactory but limited by….” (with the reason specified) indicates to the clinician that the interpretation is qualified because of the limiting factor. The adequacy statement also provides important feedback to clinicians regarding specimen collection and preparation techniques, contributing to continuous quality improvement. The adequacy statement may also indicate to the clinician the need to consider the option for early repeat testing.81, 82, 83
The Bethesda System allows for an optional interpretative statement labeled “general category”. The three general categories are within normal limits (WNL), benign cellular changes (BCC), and epithelial cell abnormality (ECA). These designations were developed for report triage and statistical monitoring. For all cases not interpreted as WNL, the report must include a descriptive interpretation that characterizes the cellular changes or abnormality. The category BCC includes specific infections and changes associated with inflammation, repair, contraceptive use, radiation, and atrophy. Some cervical/vaginal cytology specimens with reactive cellular changes will vary in interpretation when examined by multiple individuals.84 Studies of women with reactive cervical/vaginal cytology on follow up biopsy have found some intraepithelial lesions.85
The category ECA includes changes in squamous and glandular cells ranging from atypia to invasive carcinoma. The nonepithelial malignancies encountered less commonly may also be classified here. For squamous lesions, TBS terminology includes atypical squamous cells of undetermined significance (ASCUS), low grade intraepithelial lesion (LGSIL or LSIL), high grade intraepithelial lesion (HGSIL or HSIL) and squamous cell carcinoma. Some laboratories also incorporate other terminologies of dysplasia and/or cervical intraepithelial neoplasia (CIN) into their reports. For glandular lesions, TBS terminology includes atypical glandular cells of undetermined significance (AGUS) and adenocarcinoma. AGUS includes abnormalities of endocervical and endometrial cells. Some laboratories specify whether the cell of origin is most likely endocervical, endometrial or extra uterine. Endocervical adenocarcinoma in situ is reported separately by some laboratories, but in TBS is included in the AGUS category.
VI.C. Variability in Practice
Laboratories may include recommendations as part of the cervical cytology report. These may include a suggestion to the clinician for repeat cytology after a certain time interval or after treatment, or for tissue studies to further evaluate epithelial cell abnormalities. Because medical literature in this area does not indicate a consensus approach, this is one of the most variable elements of cervical cytology reporting among laboratories. Clinical professional organizations have issued Consensus Guidelines for the follow-up of abnormal Pap smear reports. Listing these consensus Guideline references on abnormal Pap reports is useful for alerting the clinician to the Guidelines (JAMA Interim Guideline,81 ACOG Technical82 ASCCP Guidelines.86, 87, 88) Furthermore, a CAP Q-Probe study of 348 laboratories showed that placing a specific follow-up recommendation on the Pap report significantly increased the likelihood of the recommended follow-up being carried out.89 Of course, implicit in any recommendation by a clinical laboratory to a clinician is that the clinician consider all known clinical circumstances and apply appropriate standards of care to their decision to follow, reject, or modify the lab’s recommendation for any individual patient.
Reporting of ASCUS and AGUS and recommended patient follow-up, for example, is variable in a number of respects. Numerous studies on follow-up of ASCUS or AGUS have been reported or are in progress. These not only indicate variability of microscopic criteria in use among laboratories, but they also recently have added the element of cost-effectiveness to clinical decision making and the value of alternative follow-up approaches.23, 90, 91
Some laboratories have chosen to include an educational explanatory note, sometimes also referred to as a “disclaimer”, on all cervical cytology reports. These notes may have several possible components. They generally note that the Pap smear is a screening procedure with the potential for false negative and false positive results. These statements serve an educational function for the clinician and are designed to encourage a dialogue between patient and clinician. They are not directed to, nor intended to be directly relied upon, by the patient. The dialogue should include the limitations of cervical cytology, an explanation of the various enhanced testing options, repeat testing intervals and any additional follow up that may be necessary.
Recently, articles and exchanges of correspondence in medical journals have addressed the content of such explanatory notes and whether or not laboratories are legally obliged to provide them; consensus is lacking among experts as to recommended practice(s).92, 93, 94, 95, 96, 97 Until further consensus is reached within the profession, the use of such explanatory notes remains at the discretion of the laboratory director. At present, there is general consensus that the clinician is in the optimal position to assess and apply follow up protocols for individual patients, and should never place sole or unquestioned reliance on the laboratory’s suggestions or recommendations.
77 Kurman RJ, Solomon D. The Bethesda system for reporting cervical/vaginal ctyologic diagnoses: Definitions, criteria, and explanatory notes for terminology and specimen adequacy. New York, NY: Springer-Verlag; 1994.
78 College of American Pathologists, 325 Waukegan Road, Northfield, Illinois 60093-2750 Web site http://www.cap.org.
79 Joint Commision on Accreditation of Health Care Organizations, One Renaissance Boulevard, Oakbrook Terrace, Illinois 60181. Web site http://www.jcaho.org
80 Davey DD, Nielsen ML, Rosenstock W, Kline TS. Terminology and specimen adequacy in cervicovaginal cytology: The CAP interlaboratory comparison program experience. Arch Pathol Lab Med. 1992; 116:903-907.
90 Stastny JF, Remmers RE, Sondon WB, et al. Atypical squamous cells of undetermined significance: a comparative review of original and automated rescreen diagnosis of cervicovaginal smears with long term follow-up. Cancer Cytopathol 1997; 81:348-353.