Introduction
The Papanicolaou (Pap) smear is a commonly employed screening test for dysplasia and cancer of the uterine cervix. Colposcopy is the diagnostic test to evaluate patients with an abnormal cervical cytologic smear or an abnormal-appearing cervix. The main goal of colposcopy is to highlight the areas of greatest abnormality in cervical intraepithelial neoplasia (CIN) or vaginal intraepithelial neoplasia (VAIN) for directed biopsy. It entails the use of a field microscope to examine the cervix after application of acetic acid (and possibly Lugol iodine) to temporarily stain the cervix and vagina. The cervix and vagina are examined under magnification, and all abnormal areas are identified. The transformation zone (TZ) is the area of the cervix extending from the original (prepubertal) squamocolumnar junction (SCJ) to the current SCJ. This and other benign colposcopic findings are listed in Table 71-1. An atypical TZ is defined as one with findings suggesting cervical dysplasia or neoplasia.
When performing a colposcopic exam, assure your patient that you will attempt to minimize pain, because this is often a consuming worry for patients. Although studies show that the sharpness of the instruments is the most important factor in the pain of a biopsy, many physicians apply topical 20% benzocaine (i.e., Hurricane solution) to decrease pain. This topical anesthetic is effective in 30 to 45 seconds. Know the pregnancy status of your patient. A nonsteroidal anti-inflammatory drug (NSAID) such as ibuprofen (800 mg) may be administered the night before and morning of the procedure unless contraindications to the drug exist.
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The goal of colposcopy is to identify and biopsy the most abnormal-appearing areas in abnormal lesions. This requires that the borders of all lesions be seen in their entirety. Colposcopy is considered satisfactory if the entire TZ (including the entire SCJ) is examined and the extent of all lesions is seen. Directed biopsies of the most severe lesions are performed, leading to a tissue diagnosis of the disease present. If the entire SCJ or the limits of all lesions cannot be completely visualized (unsatisfactory examination), a diagnostic conization with a cold knife cone, laser cone, or loop electrosurgical excisional procedure (LEEP) cone is necessary in nonadolescent patients. The uncooperative patient and the patient with a severely flexed uterus with inadequate visualization are common potential causes of unsatisfactory colposcopy. Lesions that are more likely to be missed or underread by colposcopic examination include endocervical lesions, extensive lesions that are difficult to sample, and necrotic lesions.
TABLE 71-1. Benign Colposcopic Findings View Large TABLE 71-1. Benign Colposcopic Findings Site or Condition Findings Original squamous epithelium The original squamous epithelium is a featureless, smooth, pink epithelium that has no features suggesting columnar epithelium, such as gland openings or Nabothian cysts. This epithelium is considered always squamous and was not transformed from columnar to squamous. Columnar epithelium The columnar epithelium is a single-cell layer and mucus-producing tissue that extends between the endometrium and the squamous epithelium. Columnar epithelium appears red and irregular with stromal papillae and clefts. With acetic acid application and magnification, columnar epithelium has a grapelike or sea anemone appearance. It is mostly found in the endocervix. Squamocolumnar junction (SCJ) Generally, a clinically visible line is seenon the ectocervix or within the distal endocervical canal that demarcates endocervical tissue from squamous or squamous metaplastic tissue. Squamous metaplasia It is the normal physiologic process whereby columnar epithelium matures into squamous epithelium. At the squamocolumnar junction, it appears as a "ghost white " or white-blue film with application of acetic acid. It is usually sharply demarcated toward the cervical os and has very diffuse borders peripherally. Transformation zone (TZ) The geographic area between the original squamous epithelium (before puberty) and the current squamocolumnar junction may contain gland openings, Nabothian cysts, and islands of columnar epithelium surrounded by metaplastic squamous epithelium. Vaginocervicitis Cervicitis may cause abnormal Papanicolaou (Pap) smear results and make colposcopic assessment more difficult. Many authorities recommend treatment before biopsy when a sexually transmitted disease is strongly suspected. Traumatic erosion Traumatic erosions are most commonly caused by speculum insertion and too vigorous Pap smears, but they can also result from irritants such as tampons, diaphragms, and intercourse. Atrophic epithelium Atrophic vaginal or cervical epithelium may cause abnormal Pap smears. Colposcopists often prescribe estrogen for 2 to 4 weeks before a colposcopy to "normalize " the epithelium before the examination. This is thought to be safe even if dysplasia or cancer is present because the duration of therapy is short and these lesions do not express any more estrogen receptors than a normal cervix. Nabothian cysts Nabothian cysts are areas of mucus-producing epithelium that are "roofed over " with squamous epithelium. They do not require any treatment. They provide markers for the transformation zone because they are in squamous areas but are remnants of columnar epithelium.
TABLE 71-2. Parameters Used to Grade Severity of Cervical Dysplasia View Large TABLE 71-2. Parameters Used to Grade Severity of Cervical Dysplasia Less Severe (more normal) More Severe (more dysplastic) Mild acetowhite epithelium Intensely acetowhite No blood vessel pattern Punctation No blood vessel pattern or punctation Mosaic Diffuse vague borders Sharply demarcated borders Normal surface contour of the cervix Abnormal contour or "humped up " Normal iodine reaction (dark) Iodine-negative epithelium (yellow)
Abnormal Findings
Leukoplakia is typically an elevated, white plaque on the cervical or vaginal mucosa, seen before the application of acetic acid. It results from a thick keratin layer that obscures the underlying epithelium. It may also represent exophytic human papilloma virus (HPV) disease or may signal severe dysplasia or cancer. Although it may be associated with benign findings, it generally warrants a biopsy.
Acetowhite lesions are transient, white-appearing areas of epithelium after the application of acetic acid (Table 71-2). Acetowhite changes correlate with areas of higher nuclear density in the tissue. Because both benign and dysplastic lesions may turn acetowhite, several features must be examined to estimate the severity. Assess the lesion 's margins, including the sharpness of the margin and the angularity of the contour of the margin. The margins of high-grade CIN are straighter and sharper compared with the vague, feathery, geographic borders of CIN 1 or HPV disease. Higher-grade lesions also turn white more slowly, are a dull or thick-appearing white, and may never turn yellow or totally lose their acetowhite effect. When high-grade CIN coexists in the same lesion with a lower-grade lesion, the higher-grade lesion often manifests with a sharply defined internal margin or border (i.e., border-within-a-border pattern).
With increasing levels of CIN, desmosomes (i.e., intracellular bridges) that attach the epithelium to the basement membrane are often lost, producing an edge that easily peels. This loss of tissue integrity should raise the suspicion of high-grade dysplasia. The extreme expression of this effect is the ulceration that sometimes forms with invasive disease. High-grade CIN lesions are usually adjacent to the SCJ. Higher-grade lesions often appear dull and less white than most low-grade lesions, which are usually snowy white with a shiny surface. Invasive lesions may lose the acetowhite effect altogether. Nodular elevations and ulceration may indicate high-grade disease or invasive cancer.
Increases in local factors, such as tumor angiogenesis factor or vascular endothelial growth factor, cause growth of abnormal surface vasculature, producing punctation, mosaic, and frankly abnormal (atypical) vessels. However, most high-grade lesions do not develop any abnormal vessels. Punctation is a stippled appearance of small capillaries seen end-on, often found within the acetowhite area, appearing as fine to coarse, red dots. Coarse punctation represents increased caliber vessels that are spaced at irregular intervals and is more highly associated with increasing levels of dysplasia.
The mosaic pattern is an abnormal pattern of small blood vessels suggesting a confluence of "tiles " or a "chicken-wire pattern " with reddish borders. It represents capillaries that grow on or near the surface of the lesion that form partitions between blocks of proliferating epithelium. It develops in a manner very similar to punctation and is often found in the same lesions. A coarse mosaic pattern is more highly associated with increasing levels of dysplasia.
Atypical vessels are atypical, irregular surface vessels that have lost their normal arborization or branching pattern. They represent an exaggeration of the abnormalities of punctation and mosaic, and increasing severity of the lesion. They are indicative of CIN3 or invasive cancer. These vessels are usually nonbranching, appear with abrupt courses and patterns, and often appear as commas, corkscrews, coarse parallel vessels, or spaghetti.
Lugol iodine staining (i.e., Schiller test) may be used when further clarification of potential biopsy sites is necessary. It need not be used in all cases, but the sharp outlining afforded by Lugol iodine can be dramatic and very helpful. It darkly stains epithelium containing glycogen, such as normal mature squamous epithelium. Lugol solution is often very helpful on the vagina and proximal vulva (i.e., nonkeratinized skin). It can be used to examine the entire vagina and cervix for glycogen-deficient areas, which correlate with HPV or dysplasia in nonglandular mucosa. High-grade lesions uniformly reject iodine because of the absence of glycogen and produce a beige to mustard-yellow effect.
Grading Lesions
Carefully note the shape, position, and characteristics of all lesions to draw a picture of the lesions and biopsy sites after the procedure is completed. Do not let the finding of vessels divert you from carefully observing acetowhite and border changes, because the areas with vessel abnormalities may not be the most abnormal areas on the cervix. Classically, the parameters in Table 71-2 are used to grade severity, and the more advanced findings indicate more severe dysplasia.
Leukoplakia is usually a very good sign (i.e., condylomata) or a very bad sign (i.e., high-grade CIN or squamous cell carcinoma). Abnormal vessels are always suspicious because they may indicate cancer. When multiple areas of dysplasia are present, the areas of highest-grade dysplasia are usually most proximal to the SCJ. With all other things being equal, the presence of vessel atypia in any lesion implies more severe dysplasia.
Large, high-grade lesions that cover three or four quadrants of the cervix should be carefully evaluated for the possibility of unsuspected invasive cancer. Although many lesions have vascular abnormalities, some invasive lesions are densely acetowhite and avascular. They may also manifest as ulcerative lesions. Lesions that extend >5 mm into the cervical os have an increased risk of higher-grade disease beyond the limits of the examination. Studies have shown that the more biopsies taken, the more likely significant disease will be discovered.
It is debatable whether endocervical curettage (ECC) or brushing (ECB) adds any useful information to a clearly satisfactory colposcopy, because of the high false-positive and false-negative rates. Patients in whom there is not a clear view of the cervical canal, who have had previous treatment, who gave evidence of glandular dysplasia, or who have no ectocervical lesions that explain their abnormal Pap smears should have an ECC or ECB. An ECC or ECB can be performed before or after taking biopsies, with the decision based on whether bleeding will obscure subsequent biopsy sites. Following curettage, the ECC sample appears as a coagulum of mucus, blood, and small tissue fragments. Use ring forceps or a cytobrush to gently retrieve the sample. In addition to retrieving the ECC, a cytobrush can be used to evaluate the endocervical canal. A short drinking straw placed over a cytobrush can act as a sheath to protect the brush from contamination from ectocervical disease.
Equipment
- A colposcope is typically defined as a stereoscopic binocular field microscope with a long focal length and powerful light source. Modern colposcopes permit magnification between 2 and 40 , although most routine colposcopic work can be done at 10 to 15 magnification. Some scopes have a single fixed magnification level. Others have a series of par-focal lenses or a smooth zoom capability that allows for easy adjustment of the magnification via knob or rotor.
- Interchangeable eyepieces with various levels of magnification are available. Some eyepieces can be individually adjusted to compensate for variance in an individual user 's vision. A diopter scale on the side can identify these. Eyepieces can be adjusted in a manner similar to microscopes to adjust to each colposcopist 's interpupillary distance.
- The usual working distance (focal length) of a colposcope is 30 cm. Most scopes also have a fine focus handle that is attached to a machine screw under the mounting bracket for the colposcope head. Applying pressure to this handle to subtly control the alignment of the scope and twisting it produces very gradual forward or backward movements of the head for exquisite fine focus control.
- A flexible articulating arm or overhead boom colposcope can be mounted on a stable base (with or without wheels), the wall, or an examination table. A column- or stick-mounted scope can easily be moved.
- A colposcope usually has a powerful light source, with a rheostat to adjust the level of illumination. The colposcope should be equipped with a green or blue filter (red-free filter). These filters remove red light, thereby enhancing vascular detail by making the blood vessels appear dark.
Indications
- Atypical squomous cells cannot rule out high grade disease (ASC-H), low-grade squamous epithelial lesion (LSIL), high-grade squamous epithelial lesion (HSIL), or atypical glandular cells (AGUS)
- Repeated Pap smears with atypical squamous cells
- Repeated Pap smears consistent with LSIL in a patient younger than 21 years of age
- Pap smear with repeated unexplained inflammation
- Abnormal-appearing cervix or abnormal-feeling cervix (by palpation)
- Patients with a history of intrauterine diethylstilbestrol (DES) exposure
Contraindications (Relative)
- Active cervical or vaginal infection, because it can lower test sensitivity and increase bleeding (relative contraindication)
- Severe bleeding disorders
- Late pregnancy or active labor
The Procedure
Step 1
Prepare your patient, obtain informed consent (see Appendix A), and answer her questions. If a bimanual examination was not done with the Pap smear, perform it now. Examine the vulva for obvious condylomata or other lesions. Warm the speculum with water, and gently insert it. Consider using a vaginal side-wall retractor, a Penrose drain, or latex glove thumb in obese, pregnant, or multiparous women with vaginal redundancy.
Step 2
Place the patient in the dorsal lithotomy position. Insert a speculum and position the colposcope to observe the cervix. Gross focus is achieved by moving the scope toward or away from the cervix.
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Step 3
Fine focus is achieved by knobs, handles, or motorized foot pedals that incrementally move the head of the scope forward or backward. In this illustration, the fine focus knob is controlled by the left hand.
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Step 4
Examine the cervix for inflammation or infection. Gently blot or wipe away any excess mucus using normal saline. Look for leukoplakia (shown) and abnormal vessels. When performing the procedure, apply solutions with a cotton ball held in a ring forceps or with a large swab.
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Step 5
Apply 5% acetic acid. Repeat the application every 2 to 5 minutes, as necessary. Examine the cervix, starting with low power and using white light. Determine if the colposcopy is satisfactory by identifying the squamocolumnar junction (SCJ, shown) and the extent of any lesions identified.
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Step 6
A cotton-tipped applicator soaked in vinegar may be used to move the SCJ or evert the os to examine the SCJ.
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Step 7
A Kogan endocervical speculum can greatly aid the examination of the distal endocervical canal. Use a vinegar-soaked Q-tip to help manipulate the cervix and SCJ into view, as necessary.
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Step 8
Use higher magnification and the red-free (green) filter to carefully document any abnormal vascular patterns, such as this acetowhite lesion with course punctation.
Step 9
Also note if the cervix exhibits any mosaic pattern.
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Step 10
Be sure to identify any areas with frankly abnormal blood vessels, which raises the suspicion of cancer. These vessels may take the form of nonbranching vessels, commas, corkscrews, or coarse punctation.
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Step 11
Mentally map and characterize abnormal areas, and note all margin features and vascular changes. Grade the severity of lesions. If desired, the clinician may apply Lugol solution (i.e., Schiller test, shown) and benzocaine (i.e., Hurricane solution) to the entire face of the cervix using a cotton ball.
Step 12
Perform an endocervical curettage if indicated. Use a Kevorkian curette (preferably without a basket), and scrape all walls of the canal, rotating the curette twice through 360 degrees of rotation. Place the curette into the canal until resistance is felt (Figure A), push it against the canal while pulling it out (stop short of the external os) (Figure B), and then push it back in with a slight (approximately 10-degree) twist to sample the next strip of canal with the next outward stroke (Figure C). After removing the curette, use ring forceps or a cytobrush to gently retrieve the sample.
Step 13
Alternatively, a cytobrush can be used to retrieve an ECB sample of the endocervical canal. A sheath or short drinking straw may be placed over a cervical Pap smear brush (i.e., pipe-cleaner-type brush) to act as a sheath to protect the brush from contamination by the ectocervix while the device is being introduced or withdrawn. Place the brush inside the straw, and place the straw against the os (Figure A). Advance the brush into the cervical canal, and spin it around five times (Figure B).
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Step 14
Withdraw the brush back into the straw, and remove the straw and brush from the vagina.
Step 15
Biopsy posterior abnormal-appearing areas first to avoid blood dripping over future biopsy sites. If desired, the clinician may apply benzocaine (i.e., Hurricane solution) to the entire face of the cervix using a cotton ball. If bleeding is profuse from a particular site and more biopsies are needed, apply a cotton-tipped applicator (without Monsel solution) to the area, and proceed with the next biopsy.
Step 16
Align the forceps radially from the os, so that the fixed jaw of the forceps is placed on the most posterior part of the site (Figure A). Note that the fixed position is away from the os for a lesion on the outside edge (above) and within the os when the lesion is on the inside curve (below). The jaws should be centered over the area to be biopsied (Figure B). Biopsies should be approximately 3 mm deep and should include all areas with vessel atypism.
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Step 17
Apply pressure and Monsel solution if needed (after all biopsies are completed) to bleeding sites.
Step 18
Gently remove the speculum, and view the vaginal wall collapse around the receding blades of the speculum. Inspect for any abnormal areas on the vagina or vulva. Carefully draw and label a picture of lesions and biopsy sites. Correlate the pictures with the submitted samples, if placed in different containers. Note whether the colposcopy was satisfactory.
Complications
- Vasovagal responses postprocedure
- Bleeding or spotting
- Infection (very rare)
- Uterine cramping
Pediatric Considerations
Colposcopy is rarely indicated in children. Most professional societies recommend starting cervical cytologic screening 3 years after initiation of sexual intercourse or age 21 years, whichever comes first. Because of the lower risk of cancer in adolescents, the indications for colposcopy and treatment of cervical dysplasia are more conservative. Check the American Society for Colposcopy and Cervical Pathology Web site at http://ASCCP.org for the latest evidence-based recommendations.
Postprocedure Instructions
After a colposcopy, advise patients to avoid douching, intercourse, or tampons for 1 to 2 weeks (or until the return visit). Instruct patients to return if they experience a foul vaginal odor or discharge, pelvic pain, or fever. Tylenol, ibuprofen, or naproxen sodium may be used for cramps. The follow-up visit is usually in 1 to 3 weeks to discuss pathology results and plan treatment, if necessary. With the high regression rate of CIN 1, patients should be followed with serial Pap smears or colposcopy if adequate follow-up can be ensured. CIN 2 and 3 lesions are usually treated with cervical cryotherapy, LEEP, or laser vaporization, although CIN 2 lesions may be followed with serial Pap smears and colposcopy in adolescents. Be concerned if a significant discrepancy is found between the colposcopic impression, Pap smear cytology, and biopsy histology, especially if the biopsy reports are significantly less severe than the Pap cytology. A discrepancy of two grades should be considered significant and a contraindication to ablative therapy. If the discrepancy cannot be explained or corrected on a repeat colposcopy, conization is usually indicated.
Cervical conization (i.e., cold cone, laser, or LEEP cone) is indicated in adult patients if the ECC or ECB sample reveals dysplasia, dysplasia visually extends into the cervical canal more than 3 or 4 mm, or the colposcopic results are unsatisfactory. There is a higher risk of poor outcomes if ablative therapies are used when disease is present in the endocervical canal. Positive ECC or ECB findings are sometimes a result of contamination with dysplastic lesions at the verge of the os, but this should not be assumed.
Coding Information and Supply Sources
View Large CPT Code Description 2008 Average 50th Percentile Fee Global Period 56820 Colposcopy of vulva $347.00 0 56821 Colposcopy of vulva with biopsy $473.00 0 57420 Colposcopy of entire vagina, including cervix $371.00 0 57421 Colposcopy of entire vagina with biopsy $503.00 0 57452 Colposcopy of cervix or upper vagina $327.00 0 57454 Colposcopy of cervix with biopsy, ECC $437.00 0 57455 Colposcopy of cervix with biopsy $376.00 0 57456 Colposcopy of cervix with ECC $358.00 0 57460 Colposcopy of cervix with LEEP biopsy $1,012.00 0 57461 Colposcopy of cervix with LEEP cone $1,098.00 0 57500 Cervical biopsy alone, single/multiple, or excision $307.00 0 57505 ECC alone (not part of dilatation and curettage) $270.00 10 CPT is a registered trademark of the American Medical Association.2008 average 50th Percentile Fees are provided courtesy of 2008 MMH-SI 's copyrighted Physicians ' Fees and Coding Guide.
Common ICD-9 Codes
View Large 078.11 Condyloma acuminatum 233.3 Carcinoma in situ of other and unspecified female genital organs 622.0 Erosion and ectropion of cervix 622.2 Leukoplakia of cervix (uteri) 622.7 Mucous polyp of cervix 623.1 Leukoplakia of vagina (abnormal-appearing cervix) 795.00 AGUS (all types) Papanicolaou smear 795.01 ASCUS unspecified (favor benign) Papanicolaou smear 795.02 ASC-H (favor high-grade disease or dysplasia) Papanicolaou smear 795.03 LSIL Papanicolaou smear 795.04 HSIL Papanicolaou smear 795.05 Positive high-risk HPV " also use HPV code (079.4) V10.41 Personal history of malignant neoplasm of cervix uteri V15.89 High risk for cervical dysplasia: early onset of sexual activity (age <16 years), multiple sexual partners (>4/lifetime), history of STDs (inc. HIV), <3 negative or no Pap smear within previous 7 years, DES or daughters of women who took DES during pregnancy.
Suppliers
- A 20% solution of benzocaine (i.e., Hurricane solution) can be obtained at Beutlich Pharmaceuticals LP, 1541 Shields Drive, Waukegan IL, 60085. Phone: 847-473-1100 or 1-800-238-8542. Web site: http://www.beutlich.com/products.htm.
Colposcopes and Instruments
- Cooper Surgical, Shelton, CT. Phone: 1-800-645-3760 or 203-929-6321. Web site: http://www.coopersurgical.com.
- Olympus America, Inc., Melville, NY. Phone: 1-800-548-555 or 631-844-5000. Web site: http://www.olympusamerica.com.
- Utah Medical Products, Inc., Mid-vale, UT. Phone: 1-800-533-4984 or 801-566-1200. Web site: http://www.utahmed.com.
- Wallach Surgical Devices, Inc., Orange, CT. Phone: 203-799-2000 or 1-800-243-2463. Web site: http://www.wallachsurgical.com.
- Acetic acid (3% to 5%) and normal saline can be obtained from a supermarket (i.e., white vinegar) or from a medical supply source.
Monsel solution (i.e., ferric subsulfate) performs best when it has a thick, toothpaste-like consistency. It can be bought this way or produced by allowing the stock solution to sit exposed to the air in a small open container. This allows evaporation and thickening of the agent, a process that can be enhanced by placing the open container in a warm place, such as on top of a refrigerator. The resulting paste texture can be maintained by keeping the paste in a closed container and by adding small amounts of Monsel solution whenever the paste becomes excessively thick.
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