Management of Abnormal Cervical/Vaginal Pap Smears

, University of California, San Francisco


Medscape General Medicine. 1996;1(1) 

In This Article

Common Problems Associated with Abnormal Pap Smears

No endocervical cells on Pap smear. Ideally, both glandular and squamous cells should be present on a Pap smear, because the squamocolumnar junction is sampled. When no endocervical cells (glandular cells, or ECCs) are found, it suggests that the squamocolumnar junction may not have been adequately sampled. This commonly occurs during pregnancy and in postmenopausal women. However, women who have no ECCs on Pap smears are not at increased risk of having dysplasia.[11] The Pap smear should be repeated only if the patient has not had a normal Pap smear in the previous 1 to 2 years or if poor future compliance is suspected.

Infection. Evidence of the presence of sexually transmitted organisms may be found on Pap smears. In some cases, this evidence is specific (e.g., finding a trichomonad, Fig. 3), whereas in other cases the evidence may be nonspecific (e.g., inflammatory cells). Bacterial vaginosis can be detected by the presence of clue cells (Fig. 4). In general, the Pap smear is insensitive for the diagnosis of lower genital tract infections, but it may be reasonably specific (Table IV). HPV infection can be reliably diagnosed if both nuclear and cytoplasmic changes are present (Fig. 5).

Figure 3. Pap smear showing Trichomonas vaginalis infection
Figure 4. Pap smear showing clue cells consistent with bacterial vaginosis.
Figure 5. Pap smear showing koilocytes (low-grade squamous intraepithelial lesion).

Actinomyces can also be detected on Pap smear (Fig. 6).This infection is usually detected in IUD users. Antibiotic treatment and/or removal of the IUD should be considered. Diagnosis of other infections, such as Chlamydia, is based on nonspecific findings on Pap smear and should be confirmed by culture, immunofluoresence, or DNA tests. Diagnosis of Candida (yeast, Fig. 7) on Pap smear, correlates poorly with clinical disease and is part of the normal flora in 10% to 20% of women. Candida should be treated only if the patient is symptomatic.

Figure 6. Pap smear showing Actinomyces.
Figure 7. Pap smear showing Candida.

Inflammation. Inflammation is a very common finding on a Pap smear. It is probably only significant when it is "obscuring" or "severe." Inflammation on Pap smear may reflect a genital tract infection or may be nonspecific (Fig. 8). Inflammation is often reported with a recommendation to "clear and repeat Pap smear." It is logical to clear inflammation by treating gonorrhea or Chlamydia infections when these are present, but it is uncertain how to clear inflammation in the absence of these diseases. Patients with obscuring or severe inflammation should be tested for gonorrhea and Chlamydia but should not receive empirical treatment with agents such as sulfa cream.[12] Prominent glandular tissue on the ectocervix (ectropion) appears to be a common cause of inflammation on Pap smear.[13] One study has shown cervical neoplasia in 12 of 96 women (13%) who had inflammatory changes on Pap smear.[14] Increasing the frequency of Pap smears after finding inflammation and colposcopic examination of patients who have persistent inflammation might be warranted. In populations where inflammatory Pap smears are common, a policy of routine wet mount examination at the time of screening Pap smears in asymptomatic patients might prove more manageable than recalling large numbers of patients for so-called "infection checks."[15]

Figure 8. Colposcopic photograph of a cervix showing metaplastic and inflammatory changes.

Reactive, reparative atypia. Reactive, reparative atypia (presence of immature cells formed in the process of healing or regrowth of the squamous epithelium) is a common finding that often follows treatment of dysplasia and other conditions such as cervical or vaginal infections. It is a benign finding that does not warrant increased surveillance.

Glandular atypia (atypical glandular cells of undetermined significance: AGUS). Since endocervical glands are further removed from the surface of the cervix than is the squamous epithelium, they are less well sampled by Pap smear (Fig. 9). Glandular atypia must therefore be evaluated by colposcopy and biopsy and not merely followed with repeat Pap smears. Abnormal glandular cells can also be seen in cases of endometrial, tubal, or ovarian neoplasms. Studies of series of women with AGUS Pap smears suggest the occurrence of dysplasia or carcinoma in at least 30% of patients.[16] Occasionally, an ovarian carcinoma will be found in a patient who presents with severely atypical glandular cells on Pap smear.

Figure 9. Colposcopic photograph of a cervix showing an acetowhite, glandular canal lesion (adenocarcinoma-in-situ).

Squamous atypia (ASCUS). Pap smears with atypia cannot be disregarded, because a significant number of women who have cervical cancer have had Pap smears with atypia in the past, and a significant percent (15%-25%) of those with persistent atypia on Pap smears have dysplasia.[17] Atypia can be followed by repeated Pap smears in patients who are expected to be compliant and not otherwise at high risk for dysplasia (such as HIV-infected women). If atypia (especially when favoring dysplasia) persists for 1 year, colposcopy is probably indicated. There is some evidence to support a policy of colposcopic examination after a single ASCUS smear in young high-risk women of low socioeconomic status.[18]

LSIL. Natural history studies have shown that two-thirds of LSIL lesions will regress to normal without treatment (over 6 years of follow-up), 20% will remain LSIL, 10% will progress to HSIL, and 1% or less will progress to cancer.[19] Therefore, although the vast majority of patients with LSIL probably do not need treatment, there is a small but measurable risk of progression to cancer in this group, even if the Pap smear shows only LSIL. The Interim Guidelines of the NCI recommend Pap smear follow-up of LSIL until 3 consecutive normal smears are obtained.[20] This protocol can be safely followed in compliant women who are not otherwise at high risk, but an endpoint must be chosen at which colposcopy will be performed if the Pap smears continue to be abnormal. I suggest that a patient with an LSIL smear be followed by cytology alone for no more than one year. After this time, colposcopy and biopsy should be performed.

There is a small but finite risk of development of invasive cancer during cytologic follow-up (observation) of women with LSIL.[21] A recent randomized study found that a policy of repeated cytologic screening for women with mild and moderate cervical dysplasia was not efficient. At the end of the study, only 197 of 793 women had normal Pap smears.[22]

When LSIL is diagnosed by biopsy, treatment is optional in compliant patients. In young women, treatment of LSIL should consist of cryosurgery or laser and not excisional techniques such as loop excision or cone biopsy. This is because the former therapies are effective and the latter can theoretically compromise the reproductive function of the cervix by removal of stromal tissue (which could impair the ability of the cervix to hold a pregnancy) or endocervical glands (which produce mucous important in facilitating fertilization). Alternatively, women with LSIL may be followed with serial Pap smears and can be considered "cured" when 3 consecutive normal Pap smears are obtained. If abnormal Pap smears persist for 1 year, or if an HSIL Pap smear is obtained at any time, colposcopy should be performed.

HSIL. There is no controversy about management of patients with high-grade SIL Pap smears. These warrant prompt colposcopic evaluation, cervical biopsy, and treatment (Fig. 10-12).

Figure 10. Pap smear showing a high-grade squamous intraepithelial lesion (severe dysplasia)
Figure 11. Colposcopic photograph of a cervix showing an acetowhite lesion on the ectocervix (CIN 2)
Figure 12. Colposcopic photograph of a cervix showing an acetowhite area with punctation at the squamocolumnar junction (microinvasion)

Pap smear screening effectively reduces the risk of invasive cervical cancer. It is important to understand which abnormalities are associated with malignancy. Abnormal Pap smears are commonly encountered in office pratice. Their management is simple in most cases but controversial in others.