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Follow-up is based on consensus guidelines.205

Specificity based on <LSIL. Risk of positive HPV is higher in younger women. *Based on abnormalities of LSIL or greater. Sensitivity based on >LSIL. £Based on abnormalities of HSIL or greater.

Follow-up is based on consensus guidelines.205

Specificity based on <LSIL. Risk of positive HPV is higher in younger women. *Based on abnormalities of LSIL or greater. Sensitivity based on >LSIL. £Based on abnormalities of HSIL or greater.

The true-positive rate was reported by some investigators as 13% higher for LBC compared with conventional Pap, but the false-positive rate was also increased by 12%. These findings suggest that LBC has a higher sensitivity and lower specificity than the conventional Pap smear.71,74

Because detection errors limit the efficacy of Pap and LBC techniques, there has been an effort to automate the interpretive process and improve detection.74 Studies are under way to use computer software to analyze images of LBC preparations, but these systems are not yet in widespread use.74-76

Although cytology remains the accepted screening method in the United States, other methods exist, including direct visualization of the cervix and analysis of intrinsic or reflected light emission from the cervix. Direct visual inspection (DVI) is a technique first used in the 1930s and then abandoned with the introduction of the Pap smear. However, DVI is reappearing in the developing world because it has the advantage that when an abnormality is identified, it can be dealt with during the same visit.77 Sensitivity for CIN appears comparable between DVI and Pap smear, but specificity is lower with DVI. An alternative to DVI is to use a photograph that can be analyzed by a physician (cryptography). However, this technique appears to have lower sensitivity than either Pap or DVI and is, therefore, not recommended. Finally, new technologies are being developed that involve the spectro-scopic evaluation of light reflected from the cervix. Although this technology is in its infancy, it holds promise for the detection of CIN2 and CIN3 because the early neoplastic cells present with these conditions reflect light differently from normal tissue.77

HPV testing may someday be an alternative to cytologic screening for cervical cancer, but current knowledge is inadequate to adopt it as the primary screening tool.64 HPV testing involves identifying and typing HPV in cervical mucus. It appears most useful in managing women with ASCUS as only those with HPV may need monitoring.78

Summary of the Evidence for the Benefit of Cervical Screening Tests

Evidence for the benefit of cervical cancer screening comes from cohort studies conducted in countries with active screening programs. This evidence is summarized in Table 24.4; it shows a 24% to 70% reduction in invasive cervical cancer incidence and a 22% reduction in mortality with the implementation of screening programs. The evidence is so convincing across published studies that virtually no one advocates for randomized trials or questions the impact of cervical cancer screening by cytology.

One area of controversy, however, is the frequency with which cervical cancer screening should occur. As our understanding of the slow progression of this disease has grown, screening intervals recommended by U.S. organizations have widened. As noted above, even change from HSIL to invasive cancer takes an estimated mean of 41 months, so most now believe that screening may occur successfully at intervals as infrequent as every 3 years with a low risk of invasive cancer development.9 One group of investigators estimates that after three negative Pap smears, the risk associated with screening every 3 years, compared with annually, is as low as 3 in 100,000.79 Others suggest that setting a fixed screening rate for all women does not make sense. Because the risk varies with age and sexual history, they recommend varying the frequency from 1 to 5 years depending upon risk.80

Recommendations

The ACS recently reviewed the new data on cervical cancer and updated its recommendations. ACS now recommends that screening begin 3 years after onset of sexual activity or by age 21 and may stop at age 70 if the low-risk status of the woman is established (i.e., three or more negative screens within 10 years and no high-risk conditions such as HIV, in utero DES exposure, immunocompromise by organ transplantation, chemotherapy, or chronic corticosteroid treatment). The ACS recommends an annual Pap up to age 30, and then every 2 to 3 years after three successive adequate negative Pap smears. Because of the greater sensitivity of LBC, the Society recommends screening every 2 years to age 30 if LBC is used, then every 2 to 3 years if it has been established by history and Pap results that the woman is at low risk.

Based on indirect evidence, the USPSTF recommends that screening begin within 3 years of onset of sexual activity or by age 21 and that it end at age 65 if women have had negative Pap smears and are otherwise at low risk. They recommend screening at least every 3 years.81,82

A Disquistion On The Evils Of Using Tobacco

A Disquistion On The Evils Of Using Tobacco

Among the evils which a vitiated appetite has fastened upon mankind, those that arise from the use of Tobacco hold a prominent place, and call loudly for reform. We pity the poor Chinese, who stupifies body and mind with opium, and the wretched Hindoo, who is under a similar slavery to his favorite plant, the Betel but we present the humiliating spectacle of an enlightened and christian nation, wasting annually more than twenty-five millions of dollars, and destroying the health and the lives of thousands, by a practice not at all less degrading than that of the Chinese or Hindoo.

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