False negative reactions Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Rev Bras Ginecol Obstet. 2007;29(8):402-407
DOI 10.1590/S0100-72032007000800004
PURPOSE: to evaluate the efficiency of the 100% rapid rescreening in the detection of false-negative results and to verify whether the results vary according to the adequacy of the sample and the woman’s age group. METHODS: to evaluate the efficiency of the rapid rescreening, the 5,530 smears classified as negative by the routine screening, after being submitted to the rapid rescreening of 100%, were compared with the rescreening of the smears on the basis of clinical criteria and 10% random rescreening. For statistical analysis, the variables were evaluated descriptively and the c² test and the Cochran-Armitage test were applied to compare results. RESULTS: of the 141 smears identified as suspicious according to the rapid rescreening method, 84 (59.6%) cases were confirmed in the final diagnosis, of which 36 (25.5%) were classified as atypical squamous cells of undetermined significance, five (3.5%) as atypical squamous cells that cannot exclude high-grade squamous intraepithelial lesion, 34 (24.1%) as low-grade squamous intraepithelial lesion, six (4.3%) as high-grade squamous intraepithelial lesion, and three (2.1%) as atypical glandular cells. Of the 84 suspect smears confirmed in the final diagnosis, 62 (73.8%) smears were classified as adequate and 22 (26.2%) as adequate but with some limitation, but no significant difference was observed with the woman’s age. CONCLUSIONS: the results of this study show that rapid rescreening is an efficient option for internal quality control for the detection of false-negative cervical smear results. In addition, it should be noted that rapid rescreening performed better when the sample was classified as adequate for analysis; however, it did not vary according to the woman’s age group.
Summary
Rev Bras Ginecol Obstet. 2007;29(8):402-407
DOI 10.1590/S0100-72032007000800004
PURPOSE: to evaluate the efficiency of the 100% rapid rescreening in the detection of false-negative results and to verify whether the results vary according to the adequacy of the sample and the woman’s age group. METHODS: to evaluate the efficiency of the rapid rescreening, the 5,530 smears classified as negative by the routine screening, after being submitted to the rapid rescreening of 100%, were compared with the rescreening of the smears on the basis of clinical criteria and 10% random rescreening. For statistical analysis, the variables were evaluated descriptively and the c² test and the Cochran-Armitage test were applied to compare results. RESULTS: of the 141 smears identified as suspicious according to the rapid rescreening method, 84 (59.6%) cases were confirmed in the final diagnosis, of which 36 (25.5%) were classified as atypical squamous cells of undetermined significance, five (3.5%) as atypical squamous cells that cannot exclude high-grade squamous intraepithelial lesion, 34 (24.1%) as low-grade squamous intraepithelial lesion, six (4.3%) as high-grade squamous intraepithelial lesion, and three (2.1%) as atypical glandular cells. Of the 84 suspect smears confirmed in the final diagnosis, 62 (73.8%) smears were classified as adequate and 22 (26.2%) as adequate but with some limitation, but no significant difference was observed with the woman’s age. CONCLUSIONS: the results of this study show that rapid rescreening is an efficient option for internal quality control for the detection of false-negative cervical smear results. In addition, it should be noted that rapid rescreening performed better when the sample was classified as adequate for analysis; however, it did not vary according to the woman’s age group.
Summary
Rev Bras Ginecol Obstet. 2007;29(3):158-164
DOI 10.1590/S0100-72032007000300008
Axillary nodal metastasis is still the most important breast cancer prognostic factor. As in approximately 80% of the patients with tumors measuring less than 2 cm the axillary lymph nodes are negative, it has been proposed sentinel lymph node biopsy, reducing surgical morbidity in the patients with negative result. Recently, this technique has been widely used in Brazil, but there are two questions that need to be answered: what is the probability of a false-negative result (not diagnosing a positive lymph node) and if the understaging by false-negative result exposes the patient to the risk of axillary recurrence or even distant metastases, due to less effective surgical and adjuvant therapy. The literature shows that the false-negative rate varies from 5 to 10%, being the surgeon's experience the major factor that contributes to improved results. Although axillary relapse is rare, it is not yet possible to evaluate the long term effect of not removing positive lymph nodes, due to short follow-up. The recommendation is that sentinel lymph node biopsy should only be performed by surgeons with experience confirmed by a low false-negative rate.
Summary
Rev Bras Ginecol Obstet. 2007;29(3):158-164
DOI 10.1590/S0100-72032007000300008
Axillary nodal metastasis is still the most important breast cancer prognostic factor. As in approximately 80% of the patients with tumors measuring less than 2 cm the axillary lymph nodes are negative, it has been proposed sentinel lymph node biopsy, reducing surgical morbidity in the patients with negative result. Recently, this technique has been widely used in Brazil, but there are two questions that need to be answered: what is the probability of a false-negative result (not diagnosing a positive lymph node) and if the understaging by false-negative result exposes the patient to the risk of axillary recurrence or even distant metastases, due to less effective surgical and adjuvant therapy. The literature shows that the false-negative rate varies from 5 to 10%, being the surgeon's experience the major factor that contributes to improved results. Although axillary relapse is rare, it is not yet possible to evaluate the long term effect of not removing positive lymph nodes, due to short follow-up. The recommendation is that sentinel lymph node biopsy should only be performed by surgeons with experience confirmed by a low false-negative rate.