Cervical fluorescence of normal women

BACKGROUND AND OBJECTIVE

Cervical tissue fluorescence spectra have previously been measured in vivo in women with a recent abnormal Papanicolaou smear. Diagnostic algorithms have been developed to diagnose squamous intraepithelial lesions (SILs) based on these fluorescence emission spectra. However, algorithms have not been tested in women with no history of cervical neoplasia.

STUDY DESIGN/MATERIALS AND METHODS

Cervical fluorescence was measured from 54 women with no history of cervical dysplasia, and the spectra were compared to those from colposcopically normal sites in women with suspected dysplasia. Representative spectra from each group were compared and a two-sided, unpaired Student's t-test was performed to compare mean principal component scores used in previously published diagnostic algorithms. The ability of previously reported diagnostic algorithms to classify these samples as normal tissue was also assessed.

RESULTS

At the 0.05 level of significance, the mean scores of 4 of the 7 important principal components were statistically different for the two populations. However, when the data collected from volunteers in this study were preprocessed in the appropriate manner and the algorithms were applied, more normal samples were correctly classified than in the previous clinical study in which these algorithms were developed.

CONCLUSION

Previously reported algorithms can accurately classify tissue type based on spectra from women with and without a history of cervical neoplasia.

Screening for squamous intraepithelial lesions with fluorescence spectroscopy

OBJECTIVE

To evaluate the accuracy of fluorescence spectroscopy in screening for squamous intraepithelial lesions (SILs) and to compare its performance with that of Papanicolaou smear screening, colposcopy, cervicoscopy, cervicography, and human papillomavirus (HPV) testing.

DATA SOURCES

Receiver operating characteristic (ROC) curve analysis was used to analyze performance by fluorescence spectroscopy (primary data) and other methods (secondary data).

METHODS OF STUDY SELECTION

In our search, 275 articles were identified in MEDLINE (1966-1996). Articles were included if the investigators had studied a population in whom low disease prevalence was expected; used either Papanicolaou smear screening and colposcopy or colposcopically directed biopsy as a standard against which the screening technique was measured, and included enough data for recalculation of reported sensitivities and specificities.

TABULATION, INTEGRATION, AND RESULTS

Receiver operating characteristic curves for fluorescence spectroscopy were calculated using a Bayesian algorithm, and ROC curves for the other screening methods were constructed using metaanalytic techniques. Areas under the ROC curves and Q points were calculated. Screening colposcopy had the highest area under the curve (0.95), followed by screening cervicography (0.90), HPV testing (0.88), cervicoscopy (0.85), fluorescence spectroscopy (0.76), and Papanicolaou smear screening (0.70).

CONCLUSION

In terms of screening for SILs, fluorescence spectroscopy performed better than the standard technique, Papanicolaou smear screening, and less well than screening colposcopy, cervicography, HPV testing, and cervicoscopy. The promise of this research technique warrants further investigation.

Performance estimation of diagnostic tests for cervical precancer based on fluorescence spectroscopy: effects of tissue type, sample size, population, and signal-to-noise ratio

Fluorescence spectroscopy may provide a cost-effective tool to improve precancer detection. We describe a method to estimate the diagnostic performance of classifiers based on optical spectra, and to explore the sensitivity of these estimations to factors affecting spectrometer cost. Fluorescence spectra were obtained at three excitation wavelengths in 92 patients with an abnormal Papanicolaou smear and 51 patients with no history of an abnormal smear. Bayesian classification rules were developed and evaluated at multiple misclassification costs. We explored the sensitivity of classifier performance to variations in tissue type, sample size, tested population, signal to noise ratio (SNR), and number of excitation and emission wavelengths. Sensitivity and specificity could be evaluated within +/- 7%. Minimal decrease in diagnostic performance is observed as SNR is reduced to 15, the number of excitation-emission wavelength combinations is reduced to 15 or the number of excitation wavelengths is reduced to one. Diagnostic performance is compromised when ultraviolet excitation is not included. Significant spectrometer cost reduction is possible without compromising diagnostic ability. Decision-analytic methods can be used to rate designs based on incremental cost-effectiveness.

Nuclear morphometry as an intermediate endpoint biomarker in chemoprevention of cervical carcinoma using alpha-difluoromethylornithine

The use of nuclear morphometry as an intermediate endpoint biomarker is described in a Phase I, dose-seeking trial of chemoprevention of cervical cancer, using the agent alpha-difluoromethylornithine (DFMO). Thirty patients with grade III cervical intraepithelial neoplasia (CIN III) were enrolled, and these received daily doses of DFMO at 0.06-1.0 mg/m(2) for a period of 1 month. Fifteen patients were observed to have a complete or partial regressive response to the agent, as assessed by histopathology. No significant differences in cell feature measurements were found between responders and nonresponders in specimens obtained before treatment, indicating that it may be difficult to predict response on the basis of these measurements. In specimens collected after treatment, large differences in morphometric features were observed between responders and nonresponders, indicating a differential effect of DFMO. Significantly modulated features were considered in terms of their correlations with CIN grade, which was determined from an independent set of measurements from archival tissue. Differences between features were consistent with a deletion of cells with high grade nuclei in the responders, and with the persistence of a more heterogeneous population of high grade cells in the nonresponders. Based on an independent set of measurements from archival material, a morphometric index of progression was derived, yielding a quantitative measure of the degree of nuclear atypia in these lesions. When applied to this trial, the morphometric index was seen to be specifically and consistently decreased in responsive lesions, and unchanged in nonresponders. The study indicates that morphometric features fulfill the requirements for an intermediate endpoint biomarker of cervical cancer chemoprevention.

Fluorescence spectroscopy of the cervix: influence of acetic acid, cervical mucus, and vaginal medications

BACKGROUND AND OBJECTIVE

Fluorescence spectroscopy has been shown to provide information useful in the detection of cervical dysplasia. The goal of this study was to determine if substances found on the cervix such as acetic acid, mucus, and vaginal medications can influence the fluorescence in the spectral region useful for discriminating normal cervical tissue from abnormal tissue.

STUDY DESIGN/MATERIALS AND METHODS

Fluorescence spectra were collected at 337 nm excitation from the cervix in vivo both before and after application of acetic acid; the data were analyzed to identify the effects of the acetic acid on the spectra. Cervical mucus was acquired from patients referred for colposcopy and frozen until measurements were taken. Fluorescence excitation-emission matrices (EEMs) were measured for the mucus samples. Additionally, the transmission spectra of mucus were measured to determine if its absorption could influence the fluorescence signal measured from the tissue. EEMs were measured for samples of commonly prescribed vaginal medications. All EEMs were compared to those of cervical biopsies.

RESULTS

Acetic acid introduces changes in both the lineshape and intensity of the spectra. On average, the changes are more significant in spectra of abnormal tissue. Cervical mucus was found to have no significant absorption bands, but the measured fluorescence was approximately the same order of magnitude as that measured from the cervix in vitro. Most medications exhibited significant fluorescence in the spectral region of diagnostic interest for the cervix.

CONCLUSIONS

Acetic acid appears to increase the differences in fluorescence emission spectra of normal and pre-cancerous cervical tissues; thus, its use is beneficial. The presence of cervical mucus can possibly interfere with the collection of fluorescence spectra for tissue classification. Patients should not use vaginal preparations during the 48 hours prior to tissue fluorescence measurements.

Outcome and reproductive function after chemotherapy for ovarian dysgerminoma

PURPOSE

To review the outcome for all patients with ovarian dysgerminoma treated at the M.D. Anderson Cancer Center who received bleomycin, etoposide, and cisplatin (BEP) and to assess the menstrual and reproductive function of those who received conservative treatment.

PATIENTS AND METHODS

Clinical information was abstracted from the medical record. Patients completed a detailed questionnaire about menstrual and reproductive function; those who did not return the questionnaire were interviewed by telephone.

RESULTS

Twenty-six patients were identified as having been treated with BEP chemotherapy for pure ovarian dysgerminoma from January 1984 to January 1998. Their median age was 19.5 years (range, 7 to 32 years). Sixteen patients underwent fertility-sparing surgery in the form of unilateral salpingo-oophorectomy. At a median follow-up time of 89 months, 25 (96%) of the 26 patients remained continuously disease-free. One patient apparently developed a second primary dysgerminoma in her remaining ovary after BEP and was clinically disease-free after further treatment. Of the 16 patients who underwent fertility-sparing surgery, one was lost to follow-up when she was pregnant, and one was still premenarchal. Of the remaining 14 patients, 10 (71%) maintained their normal menstrual function during and after chemotherapy, and 13 (93%) had returned to their prechemotherapy menstrual pattern at the time of the questionnaire. Five pregnancies have occurred thus far, and two patients have had difficulty conceiving.

CONCLUSION

Most patients with metastatic dysgerminoma can expect cure with maintenance of normal reproductive function when treated with conservative surgery and BEP chemotherapy.

Expression of human papillomavirus E7 mRNA in human oral and cervical neoplasia and cell lines

Human papillomaviruses (HPVs) have been strongly linked to progression of human cancers, such as cervical and oral cancers. Two HPV oncoproteins, E6 and E7, can inhibit the tumor suppressor proteins, p53 and pRB, respectively, resulting in a deregulation of the cell cycle. In order to further test the significance of HPV expression in oral and cervical carcinogenesis, we analyzed HPV E7 mRNA in oral and cervical neoplasia and cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR). We found that HPV E7 mRNA was present in 90% of patients with oral neoplasia and 100% of patients with cervical neoplasia. Quantitative RT-PCR and western blot analysis on both transformed cervical and oral epithelial cell lines demonstrated that the mRNA level of HPV-16 E7 corresponded to E7 protein level, suggesting that HPV oncogene expression is primarily regulated at the transcriptional or post-transcription level. The potential clinical application of quantitative RT-PCR for HPV E7 mRNA expression in cancer screening and treatment evaluation requires further investigation.

Decreased expression of retinoic acid receptors, transforming growth factor beta, involucrin, and cornifin in cervical intraepithelial neoplasia

Cervical intraepithelial neoplasia (CIN) I, II, and III represent a spectrum of premalignant epithelial changes and are ideal targets for application of chemoprevention strategies. Intermediate end point biomarkers are increasingly being used as surrogate end points to monitor clinical chemoprevention trials. To identify potential biomarkers in cervical epithelium, we analyzed the expression of nuclear retinoic acid receptor (RAR) mRNA by in situ hybridization, involucrin, cornifin, and transforming growth factors (TGFs) beta1 and beta2 by immunohistochemistry in cervical specimens, which contained adjacent normal epithelium and CIN lesions from 52 patients. These biomarkers were expressed in all adjacent normal cervical epithelia, whereas all CIN lesions including CIN I, CIN II, and CIN III exhibited decreased expression of RAR-alpha by 55.8%, RAR-beta by 64.7%, RAR-gamma by 54.9%, involucrin by 80.8%, cornifin by 88.5%, TGF-beta1 by 89.7%, and TGF-beta2 by 85.7%. Viewed as a whole, these biomarkers were down-regulated in 100% of the CIN lesions. Because all of these biomarkers can be modulated in vitro by retinoids, they may serve as intermediate biomarkers for retinoid chemoprevention trials in the patients with CIN lesions.

Evaluation of cellular immune responses in rhesus monkeys subjected to adenovirus-mediated gene transfer into the cervix

We reported previously that direct injection of a recombinant adenovirus (rAd), Ad5CMV-beta-gal, into the cervix of the rhesus monkey resulted in efficient beta-galactosidase expression in the cervix within 3 days. In these studies, we also observed the induction of anti-adenovirus (Ad)-specific immunoglobulin G responses after 22 days. In the continuation of evaluating the anti-Ad-specific immune responses resulting from this approach of gene targeting to the cervix, we measured the cellular immune responses. The introduction of Ad5CMV-beta-gal into the cervix by direct injection, but not by the abrasion technique, resulted in the induction of strong proliferative responses against extracts of cells infected with Ad5CMV-beta-gal but not against control uninfected cells. These responses were initially detected at 22 days postinjection and coincided with the abrogation of transgene expression. Significant levels of proliferative responses were maintained for < or =83 days. Multiple injections of rAds had no significant enhancing effect on either the level or longevity of the proliferative responses. At 3 days after the injection of Ad5CMV-beta-gal, when the transgene expression in the cervix was clearly evident, proliferative responses against the rAd were not detectable. However, the production of low but significant amounts of interleukin-10, a cytokine characteristic of T helper type 2 responses that promote humoral immune responses, was observed at the 3-day point in these animals. These results suggest that significant differences exist between the kinetics of transgene expression and the priming of specific host immune responses, and that these differences may be important for devising alternate strategies to improve techniques for Ad-mediated gene therapy of cervical cancer.

Human papillomavirus (HPV) DNA copy number is dependent on grade of cervical disease and HPV type

The association between human papillomavirus (HPV) DNA copy number and cervical disease was investigated. Viral DNA copy number for the most common high-risk HPV types in cervical cancer (types 16, 18, 31, and 45) was determined in cervical cytobrush specimens from 149 women with high-grade cervical intraepithelial neoplasias (CIN II-CIN III), 176 with low-grade CIN (CIN I), and 270 with normal cytology. Quantitative, PCR-based fluorescent assays for each of the HPV genotypes and for the beta-globin gene were used. The amount of cellular DNA increased significantly with increasing disease; thus, HPV was expressed as copies per microgram of cellular DNA. The assay had a dynamic range of >10(7), allowing documentation for the first time of the wide range of HPV copy numbers seen in clinical specimens. Median HPV DNA copy number varied by more than 10(4) among the viral types. HPV16 was present in the highest copy number; over 55% of HPV16-positive samples contained more than 10(8) copies/microgram. Median copy number for HPV16 showed dramatic increases with increasing epithelial abnormality, an effect not seen with the other HPV types. HPV16 increased from a median of 2.2 x 10(7) in patients with normal cytology, to 4.1 x 10(7) in CIN I patients, to 1.3 x 10(9) copies/microgram in CIN II-III patients. Even when stratified by cervical disease and viral type, the range of viral DNA copies per microgram of cellular DNA was quite large, precluding setting a clinically significant cutoff value for "high" copy numbers predictive of disease. This study suggests that the clinical usefulness of HPV quantitation requires reassessment and is assay dependent.

Fluorescence spectroscopy for diagnosis of squamous intraepithelial lesions of the cervix

OBJECTIVE

To calculate receiver operating characteristic (ROC) curves for fluorescence spectroscopy in order to measure its performance in the diagnosis of squamous intraepithelial lesions (SILs) and to compare these curves with those for other diagnostic methods: colposcopy, cervicography, speculoscopy, Papanicolaou smear screening, and human papillomavirus (HPV) testing.

DATA SOURCES

Data from our previous clinical study were used to calculate ROC curves for fluorescence spectroscopy. Curves for other techniques were calculated from other investigators' reports. To identify these, a MEDLINE search for articles published from 1966 to 1996 was carried out, using the search terms "colposcopy," "cervicoscopy," "cervicography," "speculoscopy," "Papanicolaou smear," "HPV testing," "fluorescence spectroscopy," and "polar probe" in conjunction with the terms "diagnosis," "positive predictive value," "negative predictive value," and "receiver operating characteristic curve."

METHODS OF STUDY SELECTION

We found 270 articles, from which articles were selected if they reported results of studies involving high-disease-prevalence populations, reported findings of studies in which colposcopically directed biopsy was the criterion standard, and included sufficient data for recalculation of the reported sensitivities and specificities.

TABULATION, INTEGRATION, AND RESULTS

We calculated ROC curves for fluorescence spectroscopy using Bayesian and neural net algorithms. A meta-analytic approach was used to calculate ROC curves for the other techniques. Areas under the curves were calculated. Fluorescence spectroscopy using the neural net algorithm had the highest area under the ROC curve, followed by fluorescence spectroscopy using the Bayesian algorithm, followed by colposcopy, the standard diagnostic technique. Cervicography, Papanicolaou smear screening, and HPV testing performed comparably with each other but not as well as fluorescence spectroscopy and colposcopy.

CONCLUSION

Fluorescence spectroscopy performs better than colposcopy and other techniques in the diagnosis of SILs. Because it also permits real-time diagnosis and has the potential of being used by inexperienced health care personnel, this technology holds bright promise.

Prevention of ovarian cancer

Chemoprevention trials with OCP and retinoids will be important to determine if these drugs are effective in selected populations. Further work will be critical to understanding the mechanism of action of OCP in preventing ovarian cancer and if this protective effect will be upheld in the high-risk population. Initial results in the Milan study are promising for the retinoids in prevention of ovarian cancer and will be used in chemoprevention trials both alone and in combination with OCP's to determine if there might be an additive effect with these drugs. As yet, little is known about preinvasive changes in the ovary to predict which women are at risk for developing ovarian cancer. We can now identify high-risk women by genetic counseling and testing, yet ultrasound and serum markers are the only modality available to evaluate these women. Research is focusing on developing ways of evaluating women, particularly those at high risk for ovarian cancer, to better understand the neoplastic process in the ovary and thus identify these women prior to their developing advanced ovarian cancer. Research is also focusing on understanding chemoprevention for ovarian cancer so that women can receive the optimal chemopreventive agent when diagnosed as high risk. Prognosis with advanced disease is so poor that early diagnosis and chemoprevention are the only methods at the current time to significantly improve survival in epithelial ovarian cancer.

A case-control study of human papillomavirus and cervical squamous intraepithelial lesions (SIL) in Harris County, Texas: differences among racial/ethnic groups

We conducted a case-control study of the association between SIL and HPV among whites (W), African Americans (AA), and Hispanics (H) in Harris County, Texas. Cases were identified at M.D. Anderson Cancer Center Colposcopy Clinic. Controls were identified among women obtaining routine Pap screening at two Harris County Health Department Clinics. HPV was detected by a PCR-based fluorescent assay. Dichotomous and polytomous logistic regression models were used to estimate adjusted odd ratios (AOR) and 95% confidence intervals (CI) for SIL among racial/ethnic groups and grade of disease. Prevalence of HPV infection was 64% in low grade SIL (LSIL), 84% in high grade SIL (HSIL), and 19% in controls. Risk of SIL was higher in H than in W and AA, AOR 29.5 (12.4-70.5), 15.3 (6.0-33.8), and 5.8 (2.6-12.6), respectively. Similarly, racial/ethnic differences were observed for both LSIL (AOR = 16.6, 7.7, and 4.3, respectively) and HSIL (AOR = 78.6, 34.6, and 14.2, respectively). Findings support the association between SIL and HPV and differences in the strength of the association with LSILs and HSILs. Data also suggest a higher risk for H and a lower risk for AA.

Noninvasive diagnosis of oral neoplasia based on fluorescence spectroscopy and native tissue autofluorescence

OBJECTIVE

To evaluate the clinical potential of fluorescence spectroscopy (a noninvasive technique for assessing the chemical and morphologic composition of tissue) for in vivo detection of oral cavity neoplasia.

DESIGN

A fluorescence spectroscopy system recorded spectra from oral cavity sites in 8 healthy volunteers and in 15 patients with premalignant or malignant oral cavity lesions at 337-, 365-, and 410-nm excitation wavelengths in the emission range of 350 to 700 nm. Fluorescence peak intensities and spectral line shapes were compared and diagnostic algorithms were developed to distinguish normal sites from abnormal sites.

SETTING

The head and neck cancer clinic at a tertiary referral center in Houston, Tex.

RESULTS

Differences were found in spectra from normal, dysplastic, and malignant oral mucosa. The fluorescence intensity of normal mucosa was greater than that of abnormal areas. In addition, the ratio of red region (635-nm) to blue region (455-490-nm) intensities was greater in abnormal areas. Diagnostic discrimination was achieved when test site spectra were compared with spectra from a normal site in the same patient. One diagnostic algorithm based on spectra at 337 nm gave a sensitivity of 88% and a specificity of 100%.

CONCLUSIONS

Consistent differences exist between the fluorescence spectra of abnormal and normal oral mucosa. Therefore, fluorescence spectroscopy has the potential to improve the noninvasive diagnosis of oral cavity neoplasia. Further studies will better define the role of this technique in the detection of premalignant and early oral cancer lesions.

A randomized clinical trial of cryotherapy, laser vaporization, and loop electrosurgical excision for treatment of squamous intraepithelial lesions of the cervix

OBJECTIVE

To compare cryotherapy, laser vaporization, and loop electrical excision for treatment of squamous intraepithelial lesions (SILs).

METHODS

Women at least 18 years old with biopsy-proven SIL, negative pregnancy tests, negative findings on endocervical curettage, satisfactory colposcopy examinations, and congruent Papanicolaou smear and biopsy results were assigned randomly to treatment after stratification by SIL grade, endocervical gland involvement, and lesion size; they were evaluated 1, 4, 8, 12, 16, 20, and 24 months after treatment. Data were analyzed using chi2 statistics, logistic regression analysis, and the Cox proportional hazards model.

RESULTS

Of 498 patients assigned, 108 were excluded (most because of inadequate follow-up), leaving 390 (139 cryotherapy, 121 laser vaporization, 130 loop excision) for analysis. All were followed 6-37 months (mean 16). There were no statistically significant differences in complications, persistence (disease present less than 6 months after treatment), or recurrence (disease present more than 6 months after treatment). Risk of persistent disease was higher among women with large lesions (risk ratio [RR], 18.9; 95% confidence interval [CI], 3.2, 110.6). Recurrence risk was higher among women aged 30 years and older (RR, 2.1; 95% CI, 1.2, 4.3), those with human papillomavirus type 16 or 18 (RR, 2.1; 95% CI, 1.1, 4.0), and those who had had prior treatment (RR, 2.1; 95% CI, 1.1, 3.9).

CONCLUSION

The data support a high success rate with all three modalities. No significant difference in success rates was observed between the three treatments in our population. Additional attention and research should be directed toward the higher risk patients identified above.

Development of a fiber optic probe to measure NIR Raman spectra of cervical tissue in vivo

The goal of this study was to develop a compact fiber optic probe to measure near infrared Raman spectra of human cervical tissue in vivo for the clinical diagnosis of cervical precancers. A Raman spectrometer and fiber optic probe were designed, constructed and tested. The probe was first tested using standards with known Raman spectra, and then the probe was used to acquire Raman spectra from normal and precancerous cervical tissue in vivo. Raman spectra of cervical tissue could be acquired in vivo in 90 s using incident powers comparable to the threshold limit values for laser exposure of the skin. Although some silica signal obscured tissue Raman bands below 900 cm-1, Raman features from cervical tissue could clearly be discerned with an acceptable signal-to-noise ratio above 900 cm-1. The success of the Raman probe described here indicates that near infrared Raman spectra can be measured in vivo from cervical tissues. Increasing the power of the excitation source could reduce the integration time to below 20 s.

Near-infrared Raman spectroscopy for in vitro detection of cervical precancers

In this study, we investigate the potential of near-infrared Raman spectroscopy to differentiate cervical precancers from normal tissues, inflammation and metaplasia and to differentially diagnose low-grade and high-grade precancers. Near infrared Raman spectra were measured from 36 biopsies from 18 patients in vitro. Detection algorithms were developed and evaluated relative to histopathologic examination. Algorithms based on empirically selected peak intensities, ratios of peak intensities and a combination of principal component analysis for data reduction and Fisher discriminant analysis for classification were investigated. Spectral peaks were tentatively identified from measured spectra of potential chromophores. Empirically selected normalized intensities can differentiate precancers from other tissues with an average sensitivity and specificity of 88 +/- 4% and 92 +/- 4%. Ratios of unnormalized intensities can differentiate precancers from other tissues with a sensitivity and specificity of 82% and 88% and high-grade from low-grade lesions with a sensitivity and specificity of 100%. Using multivariate methods, intensities at eight frequencies can be used to differentiate precancers from all other tissues with a sensitivity and specificity of 82% and 92% in an unbiased test. Raman algorithms can potentially separate benign abnormalities such as inflammation and metaplasia from precancers. Comparison of tissue spectra to published and measured chromophore spectra indicate that the most likely primary contributors to the tissue spectra are collagen, nucleic acids, phospholipids and glucose 1-phosphate. These results suggest that near-infrared Raman spectroscopy can be used for cervical precancer diagnosis and may be able to accurately separate samples with inflammation and metaplasia from precancer.

Epidermal growth factor receptor expression in cervical intraepithelial neoplasia and its modulation during an alpha-difluoromethylornithine chemoprevention trial

Chemoprevention trials designed to prevent progression to invasive cervical cancer will benefit from the identification of biomarkers that assess the risk of developing tumors, predict likelihood of response to treatment, and measure biological response to intervention. The purpose of this study was to examine expression of epidermal growth factor receptor (EGFR) as a marker for progression of cervical intraepithelial neoplasia (CIN) and as a surrogate end point biomarker in a chemoprevention trial with alpha-difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase. To evaluate quantitative and spatial changes in EGFR expression during cervical tumorigenesis, paraffin sections from 42 archival cervical cone biopsies, each containing multiple stages of CIN, were immunohistochemically stained for EGFR, and the level and spatial expression of EGFR were quantitated by image analysis. In the progression from normal epithelium to CIN 1 to CIN 2 to CIN 3 to invasive cancer, EGFR expression showed two types of changes. Normal control epithelium showed EGFR expression predominantly confined to the basal layer, while histologically normal epithelium in specimens containing CIN showed relatively increased EGFR expression in the basal layer and the extension of EGFR expression away from the basal layer. The total EGFR relative staining intensity (RSI) of epithelium increased with the degree of CIN, predominantly due to a progressive expansion of EGFR-expressing cells away from the basal layer rather than an increase in the level of EGFR expression per cell. To determine whether EGFR expression would be modulated by a 1-month chemopreventive intervention with DFMO, pretreatment and posttreatment cervical biopsy specimens from 25 patients (22 evaluable) were examined for EGFR expression. Although the overall levels of EGFR expression were not modulated in either histological responders or nonresponders, responders showed a prominent down-regulation of EGFR expression away from the basal layer after DFMO treatment. Interestingly, pretreatment EGFR expression levels predicted for DFMO response [i.e., eight responses (72.7%) for 11 cases with RSI levels below 0.35 versus one response (9.1%) for 11 cases with RSI levels above 0.35 (P < 0.01)]. These results suggest that CIN progression is associated with a spatial dysregulation of EGFR expression that can be reversed by DFMO treatment, especially in patients whose pretreatment CIN 3 lesions exhibit relatively low EGFR expression.

Polyamine measurements in the uterine cervix

Cervical cancer remains a significant health problem. New strategies based on the molecular aspects of cervical carcinogenesis are needed. Chemoprevention represents a novel strategy for cervical cancer prevention. Our group plans phase I and II trials using alpha-difluoromethylornithine, a suicide inhibitor of ornithine decarboxylase and potent antiproliferative chemopreventive agent. We conducted a study to identify which polyamines in tissue could best serve as surrogate endpoint biomarkers for future trials. Thirty patients with biopsy-proven cervical intraepithelial neoplasia grade 3 underwent colposcopically directed biopsies of normal and abnormal areas of the uterine cervix for analysis of polyamine synthesis biomarkers. Statistically significant differences were found in the ornithine decarboxylase value and the spermidine:spermine ratio between normal and abnormal areas of the cervix. In general, the ranges in measurements varied widely. Differences in polyamine synthesis biomarkers between colposcopically normal and abnormal areas can be demonstrated. However, studies using polyamine synthesis biomarkers in the cervix would require large numbers of patients to achieve significance.

Colposcopy for the diagnosis of squamous intraepithelial lesions: a meta-analysis

OBJECTIVE

To quantify by meta-analysis the performance of colposcopy to set a standard against which new technologies can be compared.

DATA SOURCES

MEDLINE was searched for articles on colposcopy for diagnosis of squamous intraepithelial lesions (SIL). The search selected articles from 1960 to 1996 combining the key word "colposcopy" with key words "diagnosis," "positive predictive value," "negative predictive value," "likelihood ratio," and "receiver operating characteristic (ROC) curve."

METHODS OF STUDY SELECTION

Articles were selected if the authors studied a population of patients with abnormal screening Papanicolaou smears and presented raw data showing for each cervical lesion type the number of patients judged positive and negative by colposcopic impression versus the standard of colposcopic biopsy results. Nine of 86 studies met these criteria.

TABULATION, INTEGRATION, AND RESULTS

Biopsies had been categorized as normal, atypia, cervical intraepithelial neoplasia (CIN) I, CIN II, CIN III, carcinoma in situ, and invasive cancer; we recalculated performance measures using the Bethesda system. Overall sensitivity, specificity, likelihood ratios, ROC curves, and the corresponding areas under the curves were calculated. The average weighted sensitivity of diagnostic colposcopy for the threshold normal compared with all cervix abnormalities (atypia, low-grade SIL, high-grade SIL, cancer) was 96% and the average weighted specificity 48%. For the threshold normal cervix and low-grade SIL compared with high-grade SIL and cancer, average weighted sensitivity was 85% and average weighted specificity 69%. Likelihood ratios generated small but important changes in probability for distinguishing normal cervix and low-grade SIL from high-grade SIL and cancer. Areas under the ROC curve were 0.80 for the threshold normal cervix compared with all abnormalities and 0.82 for the threshold normal cervix and low-grade SIL compared with high-grade SIL and cancer.

CONCLUSION

Colposcopy compares favorably with other medical diagnostic tests in terms of sensitivity, specificity, and area under the ROC curve. New diagnostic methods for the cervix can be compared with colposcopy using these quantified values.

Cost-effectiveness analysis of diagnosis and management of cervical squamous intraepithelial lesions

OBJECTIVE

To compare five strategies for the diagnosis and treatment of cervical squamous intraepithelial lesions (SILs), including those that incorporate colposcopy and a new technology, fluorescence spectroscopy.

METHODS

On the basis of a health care perspective, we performed a cost-effectiveness analysis using a decision-analytic model for the diagnosis and management of SILs. We compared the five strategies based on the expected costs and number of cases that were treated appropriately, missed, treated inappropriately, and appropriately not treated in a hypothetical cohort of 100 patients referred after an abnormal Papanicolaou smear. Data on prevalence and operating characteristics were derived from the medical literature. Costs were adjusted from hospital charge data.

RESULTS

A see-and-treat strategy based on fluorescence spectroscopy was the least expensive but least effective strategy, costing $160,479 to detect 31.55 cases of cervical precancer accurately in 100 patients. The most expensive strategy was colposcopically directed biopsy, at $311,808 to find 45.78 cases; however, when both tests were used in a see-and-treat modality, slightly more cases were found (46.05) at a lower cost ($285,133). Other strategies were dominated in the base case. The incremental cost-effectiveness of the joint strategy compared with the spectroscopy-only strategy was $8596 per case of cervical precancer detected. Sensitivity analysis showed that the analysis was sensitive to the cost of the new technology of fluorescence spectroscopy.

CONCLUSION

Fluorescence spectroscopy should be considered an important innovation in the diagnosis of SILs as demonstrated by its efficacy and economic advantages.

Phase I dose de-escalation trial of alpha-difluoromethylornithine in patients with grade 3 cervical intraepithelial neoplasia

alpha-Difluoromethylornithine (DFMO) is a suicide inhibitor of ornithine decarboxylase and potent antiproliferative chemopreventive agent. We conducted a dose de-escalation Phase I trial of DFMO in patients with grade 3 cervical intraepithelial neoplasia to determine an optimal dose of DFMO using ornithine decarboxylase activity and polyamine modulation as surrogate biomarkers and to evaluate its toxicity. Thirty patients with biopsy-confirmed grade 3 cervical intraepithelial neoplasia were assigned sequentially to one of five DFMO doses (1.000, 0.500, 0.250, 0.125, or 0.060 g/m2) given daily for 31 days. One patient was excluded from analysis for protocol violation. Polyamine levels were assessed in cervical tissue, plasma, and RBCs. Tissue and blood samples were obtained before and after treatment with DFMO. All patients underwent loop excision of the cervix at the end of the study for complete histological evaluation and definitive treatment of the premalignant condition. No major clinical toxicity was observed at any DFMO dose. A reduction in tissue spermidine to spermine (SPD:SPM) ratio and an increase in plasma arginine levels were observed among patients receiving 1.000 g/m2/day (P < 0.05). A nonsignificant reduction in SPD:SPM ratio was also observed in the 0.500 g/m2/day dose group, and a nonsignificant increase in plasma arginine level was observed down to the 0.125 g/m2/day dose level. There was no evidence of modulation of other polyamines or precursors. Fifteen patients experienced a complete (5 patients) or partial (10 patients) histological response. In conclusion, DFMO was well tolerated and significantly modulated tissue SPD:SPM ratio and plasma arginine level at the dose of 1.000 g/m2/day. To clarify whether DFMO has activity at lower doses, these results will be tested in a three-armed double-blinded Phase II study using placebo and DFMO doses of 0.500 and 0.125 g/m2/day.

DNA image cytometric measurement as a surrogate end point biomarker in a phase I trial of alpha-difluoromethylornithine for cervical intraepithelial neoplasia

Cervical intraepithelial neoplasia grade 3 (CIN 3) is considered a high-risk precursor of invasive cervical cancer. alpha-Difluoromethylornithine (DFMO) is a promising antiproliferative chemopreventive agent. The purpose of this study was to evaluate image cytometric measurement of nuclear DNA (ICM-DNA) as a surrogate end point biomarker (SEB) in a Phase I trial of DFMO for CIN. Thirty patients with CIN 3 were treated with DFMO at five doses, ranging from 0.0625 to 1.0 g/m2/day, for 1 month. Half of the patients had histological responses. Twenty-five pre- and posttreatment cervical biopsy specimens (from 11 responders and 14 nonresponders) were available for this analysis. ICM-DNA was performed on 4-micron sections cut from formalin-fixed tissue blocks and stained with a thionin-SO2 Feulgen reaction. ICM-DNAs for each case were expressed as normalized measurements (against the nuclear modal absorbance of lymphocytes) of the absorbance of each cell of interest and were presented in bar histograms. The mean normalized summed absorbance (sigma ODn) was obtained as a mean histogram of the cell population of interest. Nineteen (76%) of 25 patients had a significant decrease in sigma ODn after DFMO treatment. Posttreatment values were significantly lower than pretreatment values in a paired analysis, and responders had significantly lower values than nonresponders. Analyses of different ICM-DNA references, including percentile values of sigma ODn distribution, DNA malignancy grade, and 5c exceeding rate, showed a decrease of mean sigma ODn during DFMO treatment. In addition, the summed posttreatment sigma ODn histograms also showed progressively shorter right shoulders compared with pretreatment histograms in both responders and nonresponders. We concluded that the modulation of sigma ODn reflected the chemoprevention effect of DFMO even before morphological changes appeared, and thus, ICM-DNA may be useful as a SEB in chemoprevention trials of DFMO. Additional reasons for using ICM-DNA as a SEB are the relative simplicity of its use, the high accuracy of the results, the low cost of the reagents, the ability to use small tissue samples, and the objectivity and reproducibility of the procedure.

Progressive dysregulation of proliferation during cervical carcinogenesis as measured by MPM-2 antibody staining

To better characterize the amount and location of loss of proliferation control during cervical carcinogenesis, 44 cervical cone biopsy specimens containing various grades of premalignant and malignant lesions and 12 normal cervix specimens were immunohistochemically examined using MPM-2. This antibody recognizes a phosphorylated epitope on a group of proteins that are preferentially phosphorylated at mitosis. The spatial organization of mitotic figures was determined using a computer-assisted image analysis system. The mitotic figure frequencies/unit of epithelial area were found to increase as the histological type progressed; the numbers of mitoses/square millimeter was 1.7 +/- 0.5 (mean +/- SE) for control normal epithelium (n = 12), 3.1 +/- 1.7 for normal epithelium adjacent to cervical intraepithelial neoplasia (CIN) and cancer (n = 28), 7.9 +/- 1.3 for CIN1 (n = 24), 75.8 +/- 16.3 for CIN2 (n = 11), 127.2 +/- 9.7 for CIN3 (n = 22), 196.9 +/- 33.2 for carcinoma in situ (n = 9), and 156.2 +/- 31.0 for cervical carcinoma (n = 8). The MPM-2 index was higher in high-risk premalignant lesions (i.e., those adjacent to areas of high-grade CIN and carcinoma) than it was in lower risk premalignant lesions (i.e., those with no adjacent higher grade CIN or cervical cancer), even if they exhibited the same histological grade. Moreover, the mean relative distance of the mitotic cells from the basement membrane (i.e., the distance from the basal layer to the surface) also increased as the histological grade progressed. These results suggest that proliferation becomes sequentially dysregulated both quantitatively and spatially during cervical carcinogenesis and that the MPM-2 antibody might be useful as a proliferation biomarker.

Involvement of reactive oxygen species in N-(4-hydroxyphenyl)retinamide-induced apoptosis in cervical carcinoma cells

BACKGROUND

The inhibitory effects of N-(4-hydroxyphenyl)retinamide (4HPR) on tumorigenesis and tumor growth may result from its ability to induce apoptosis (programmed cell death). Since antioxidants inhibit 4HPR-induced apoptosis, experiments were planned to determine whether the levels of reactive oxygen species increase in cells undergoing apoptosis after exposure to 4HPR.

METHODS

Cells of the human cervical carcinoma cell line C33A and normal human cervical epithelial cells were treated with 4HPR and analyzed for survival, induction of apoptosis, generation of reactive oxygen species, and expression of the apoptosis-related proteins Bcl-2 and Bax.

RESULTS

Treatment with 4HPR decreased C33A cell number by inducing apoptosis in a time- and dose-dependent fashion. DNA fragmentation typical of apoptosis was observed in cells exposed to 4HPR at concentrations of 3 microM or higher for 6-24 hours. The generation of reactive oxygen species was enhanced by 1.85-fold to 4.5-fold after a 1.5-hour treatment with 0.4-10 microM 4HPR. Pyrrolidine dithiocarbamate, an oxygen radical scavenger, suppressed the rate of generation of reactive oxygen species and inhibited 4HPR-induced apoptosis. 4HPR failed to modulate cellular levels of the Bcl-2 and Bax proteins. N-(4-Methoxyphenyl)retinamide, the major 4HPR metabolite, and several other retinoids that bind to nuclear retinoic acid receptors or retinoid X receptors failed to enhance the generation of reactive oxygen species and to induce apoptosis. 4HPR was much less effective in generating reactive oxygen species and in inducing apoptosis in normal human cervical epithelial cells than in C33A cervical carcinoma cells.

CONCLUSIONS

Enhancement of the generation of reactive oxygen species may be involved in apoptotic pathway induction by 4HPR.

Safety analysis: relative risks of ultraviolet exposure from fluorescence spectroscopy and colposcopy are comparable

Fluorescence spectroscopy is a promising tool for use in the diagnosis of disease in human tissue. However, few published reports have evaluated the safety of this technique, despite the fact that many spectroscopic systems use UV illumination. This study determined the relative risk associated with light exposure from spectroscopic systems compared with the traditional light sources that are used to illuminate tissue and direct biopsies. We compared spectroscopic detection systems for the cervix to the colposcope, a low-power microscope routinely used to illuminate the cervix, which does not cause any known photochemical damage. We measured the average spectral irradiance (W/[cm2nm]) and the average tissue exposure time during a diagnostic colposcopy examination. To quantify the relative risks, we multiplied illumination spectra by several action spectra from the literature and compared the areas under the curves corresponding to each procedure. The risk associated with the average power colposcope served as our basis for comparison. We conclude that the risks of illumination using spectroscopic systems are lower than or comparable to those already encountered in routine diagnostic procedures such as colposcopy with an average power colposcope. Spectroscopic examination can be associated with a somewhat higher risk than a colposcopy with the lowest power colposcope or a shorter than average colposcopy. The analysis presented can be repeated to estimate the magnitude of risks associated with other spectroscopic diagnostic devices.

Adenocarcinoma of the cervix. Expression and clinical significance of estrogen and progesterone receptors

BACKGROUND

Although hormone receptor status is an important prognostic indicator in adenocarcinoma of the breast and the endometrium, few studies have investigated the expression and clinical significance of estrogen receptor (ER) and progesterone receptor (PgR) in adenocarcinoma of the cervix.

METHODS

ER and PgR expression were determined using an immunohistochemical method in 84 cervical adenocarcinomas. Clinical features and outcome were determined by chart review.

RESULTS

ER was identified in 17 of the 84 cases (20%). ER positivity was most frequently detected in mucinous adenocarcinoma of the endocervical type (in 11 of 48 cases) and endometrioid adenocarcinoma (in 4 of 10 cases). PgR was identified in 23 of the 84 cases (27%). PgR positivity was also most frequently detected in mucinous adenocarcinoma of the endocervical type (in 15 of 48 cases) and endometrioid adenocarcinoma (in 6 of 10 cases). Mucinous adenocarcinoma of the intestinal type (five cases), glassy cell carcinoma (two cases), and clear cell adenocarcinoma (two cases) were uniformly negative for both ER and PgR. No association was detected between International Federation of Gynecology and Obstetrics stage and receptor status, but there was a somewhat lower frequency of ER positivity in poorly differentiated tumors (P = 0.07). No association was detected between PgR status and disease free survival. Similarly, no association between ER status and overall survival was observed. Although ER positive tumors may be associated with longer disease free survival than ER negative tumors, this difference did not reach statistical significance in this study (P = 0.06).

CONCLUSIONS

ER and PgR positivity were found in 20% and 27%, respectively, of primary cervical adenocarcinomas. However, receptor status was not significantly associated with either overall survival or disease free survival.

Sexual adjustment of patients undergoing gracilis myocutaneous flap vaginal reconstruction in conjunction with pelvic exenteration

BACKGROUND

Although the technique for gracilis myocutaneous vaginal reconstruction was first described in the mid-1970s and has been used in conjunction with pelvic exenteration since that time, there is little available information regarding sexual adjustment after such a procedure. The purpose of this study was to assess the sexual adjustment of women who underwent pelvic exenteration and gracilis myocutaneous vaginal reconstruction at the study institution.

METHODS

In a prospective study design, 95 patients were identified who underwent pelvic exenteration and gracilis myocutaneous vaginal reconstruction at the study institution from 1977 through 1989 and a convenience sample was selected of 44 patients who completed a modified version of the Sexual Adjustment Questionnaire (SAQ) when they returned to the gynecologic oncology outpatient clinic for routine follow-up care. A vaginal assessment was also performed by the attending physician.

RESULTS

Twenty-one of 40 patients (52.5%) completing the questionnaire reported not resuming sexual activity after surgery; 19 patients reported sexual activity between 1.5 months to 12 years postoperatively. Of the patients who resumed sexual activity, 84% did so within 1 year of surgery. The most common problems noted by patients in adjusting to sexual activity after surgery were self-consciousness about the urostomy or colostomy and being seen in the nude by their partner, vaginal dryness, and vaginal discharge. The mean rank of preexenteration SAQ scores was 66.4, and the mean rank of postexenteration scores was 48.7 (P < 0.0001), demonstrating that sexual adjustment after exenteration was significantly poorer than before the surgery. On the basis of data gathered from a vaginal assessment form, 31 of 44 patients (70.4%) were judged to have a potentially functional neovagina.

CONCLUSIONS

Based on the findings of this questionnaire study, sexual adjustment is often significantly impaired in women after pelvic exenteration and gracilis myocutaneous vaginal reconstruction. Future modifications in surgical technique, more realistic patient counseling and aggressive postoperative support will hopefully minimize such problems.

Adenovirus-mediated transfer of HPV 16 E6/E7 antisense RNA to human cervical cancer cells

To explore the potential of an adenoviral antisense RNA transcript for gene therapy of cervical cancer, we introduced the antisense RNA transcript of E6 and E7 genes of human papillomavirus (HPV) 16 into cervical cancer cells harboring HPV 16 via a recombinant adenoviral vector, Ad5CMV-HPV 16 AS and analyzed the effects of expression of these genes on cell growth and tumor growth. Ad5CMV-HPV 16 AS contains the cytomegalovirus-promoter, E6 and E7 genes of HPV 16 in antisense orientation, and the SV40 polyadenylation signal in a mini-gene cassette, which is inserted into the E1-deleted region of modified adenovirus 5. The entire E6/E7 region of HPV 16 was amplified by polymerase chain reaction (PCR) before cloning into the mini-gene cassette. By reverse transcriptase-PCR, HPV 16 E6/E7 antisense RNA was detected in SiHa cells infected with Ad5CMV-HPV 16 AS. The growth of the Ad5CMV-HPV 16 AS-infected cells was greatly suppressed, as evidenced by a decrease in cell count. The growth inhibitory effect of Ad5CMV-HPV 16 AS was significantly enhanced by an adenoviral p53 construct, Ad5CMV-p53. In an ex vivo study in nude mice, tumorigenicity was completely inhibited in mice injected with Ad5CMV-HPV 16 AS-infected SiHa cells. These data suggest that transfection of cervical cancer cells with HPV 16 E6/E7 antisense RNA in a form such as Ad5CMV-HPV 16 AS is a potential novel approach to the therapy of HPV 16-positive cervical cancer.

Cervical precancer detection using a multivariate statistical algorithm based on laser-induced fluorescence spectra at multiple excitation wavelengths

A portable fluorimeter was developed and utilized to acquire fluorescence spectra from 381 cervical sites in 95 patients at 337, 380 and 460 nm excitation immediately prior to colposcopy. A multivariate statistical algorithm was used to extract clinically useful information from tissue spectra acquired in vivo. Two full-parameter algorithms were developed using tissue fluorescence emission spectra at all three excitation wavelengths (161 excitation-emission wavelength pairs) for cervical precancer (squamous intraepithelial lesion [SIL]) detection: a screening algorithm that discriminates between SIL and non-SIL with a sensitivity of 82 +/- 1.4% and specificity of 68 +/- 0.0%, and a diagnostic algorithm that differentiates high-grade SIL from non-high-grade SIL with a sensitivity and specificity of 79 +/- 2% and 78 +/- 6%, respectively. Multivariate statistical analysis was also employed to reduce the number of fluorescence excitation-emission wavelength pairs needed to redevelop algorithms that demonstrate a minimum decrease in classification accuracy. Two reduced-parameter algorithms that employ fluorescence intensities at only 15 excitation-emission wavelength pairs were developed: the screening algorithm differentiates SIL from non-SIL with a sensitivity of 84 +/- 1.5% and specificity of 65 +/- 2% and the diagnostic algorithm discriminates high-grade SIL from non-high-grade SIL with a sensitivity and specificity of 78 +/- 0.7% and 74 +/- 2%, respectively. Both the full-parameter and reduced-parameter screening algorithms discriminate between SIL and non-SIL with a similar specificity (+/-5%) and a substantially improved sensitivity relative to Pap smear screening. A comparison of the full-parameter and reduced-parameter diagnostic algorithms to colposcopy in expert hands indicates that all three have a very similar sensitivity and specificity for differentiating high-grade SIL from non-high-grade SIL.

Adenocarcinoma in situ of the cervix: significance of cone biopsy margins

OBJECTIVE

To evaluate the treatment and outcome of patients with adenocarcinoma in situ of the cervix, with special emphasis on cone biopsy margins.

METHODS

Sixty-one women with adenocarcinoma in situ of the cervix treated between April 1984 and December 1993 were identified. Medical records and histologic material were reviewed. Mixed lesions with both adenocarcinoma in situ and squamous cervical intraepithelial neoplasia (CIN) were included.

RESULTS

The mean age of the patients was 35.9 years. Fifty-five of the 61 (90%) patients had cone biopsies, and 44 of these 55 (80%) subsequently had hysterectomies. Eight women (13%) had associated invasive cancer. Among 50 patients in whom the status of the margins was confirmed, 23 (46%) had positive margins and 27 (54%) had negative margins. Of 23 women with positive margins, 19 had hysterectomies and ten of the 19 (53%) had residual disease in the uterus. Of 27 patients with negative cone margins, 21 had hysterectomies, and seven of the 21 (33%) had residual disease in the uterus. Two women with negative margins who did not have hysterectomies developed recurrent disease. Fifty-five of the total series of 61 patients followed-up for a median of 57 months (range 17-132) had no evidence of disease at last follow-up.

CONCLUSION

Women with adenocarcinoma in situ of the cervix often have residual disease in the uterus, regardless of whether the margins on cone biopsy are positive or negative.

Adenovirus-mediated transfer of a wild-type p53 gene and induction of apoptosis in cervical cancer

In most cervical cancers, the function of p53 is down regulated. To explore the potential use of p53 in gene therapy for cervical cancer, we introduced wild-type p53 into cervical cancer cell lines via a recombinant adenoviral vector, Ad5CMV-p53, and analyzed its effects on cell and tumor growth. The transduction efficiencies of all cell lines were 100% at a multiplicity of infection of 100 or greater. The p53 protein was detected in Ad5CMV-p53-infected cells. Protein expression peaked at day 3 after infection and lasted 15 days. The Ad5CMV-p53-infected cells underwent apoptosis, and cell growth was greatly suppressed. The Ad5CMV-p53 treatment significantly reduced the volumes of established s.c. tumors in vivo. These results indicate that transfection of cervical cancer cells with the wild-type p53 gene via Ad5CMV-p53 is a potential novel approach to the therapy of cervical cancer.

Transgene expression in the rhesus cervix mediated by an adenovirus expressing beta-galactosidase

OBJECTIVES

More than 90% of cervical cancers are positive for human papillomavirus, which functionally represses p53 and pRb. The remainder have been found to contain p53 mutations. Gene therapy involves insertion of a functioning gene into a patient to correct a genetic abnormality.

STUDY DESIGN

The ability of a beta-galactosidase adenovirus to mediate transgene expression in the rhesus cervix was evaluated. Three different doses and two different entry techniques of virus were investigated.

RESULTS

The ideal dose determined by X-galactosidase staining was 2 x 10(10) plaque-forming units, and the injection method yielded better staining than did abrasion with topical application. Increased adenoviral-specific immunoglobulin G antibody response in the injected monkeys confirmed the results.

CONCLUSION

High transduction efficiency by use of adenoviral vectors can be achieved in the cervix. Reversing the effects of human papillomavirus and p53 mutations with gene therapy may become a novel therapy for invasive and preinvasive cervical cancer.

Growth inhibition of human cervical cancer cells with the recombinant adenovirus p53 in vitro

Human papillomavirus (HPV) has been identified in the majority of invasive cancers of the uterine cervix sampled and has been found to contribute in a significant way to the genesis of human cervical cancer. HPV has two transforming genes that encode the oncoproteins E6 and E7. E6 can form complexes with p53 and promote p53 degradation. We introduced wild-type p53 into a cervical cancer cell line via a recombinant adenoviral vector, Ad5CMV-p53. Human cervical cancer cell line HeLa, which has HPV type 18 and wild-type p53, was used in this study. Cells were grown in RPMI medium supplemented with 10% heat-inactivated fetal bovine serum. Ad5CMV-p53 was created by inserting the cytomegalovirus promoter, wild-type p53 cDNA, and SV40 polyadenylation signal in a minigene cassette into the E1-deleted region of the modified Ad5 adenovirus. The transduction efficiency was 100% when a dose ensuring a multiplicity of infection of 100 or greater was used. The p53 protein was detected in Ad5CMV-p53-infected cells by immunohistochemical and Western blot analyses. The growth of the Ad5CMV-p53-infected cells was greatly suppressed as detected by both cell count and [3H]thymidine incorporation assay. These data suggest that transfection of HPV-positive cervical cancer cells with a wild-type p53 gene in a form such as Ad5CMV-p53 is a potential novel therapy for cervical cancer.

Detection of genomic alterations in human cervical cancer by two-dimensional gel electrophoresis

Two-dimensional gel electrophoresis was used to comprehensively scan the whole genome of 6 cervical intraepithelial neoplasia (CIN) lesions, 7 cervical squamous cell carcinomas, 1 cervical adenosquamous cell carcinoma, and 2 cervical adenocarcinomas for multiple genetic alterations, such as DNA amplification, chromosome deletion, loss of heterozygosity, and chromosome translocation, as compared with the paired normal tissues. DNA spot analysis of the genomic 2-dimensional gels was performed by a computer color overlay system and by spot recognition software allowing for objective spot comparison and quantitation. Nine spots were found to be amplified in the cervical carcinomas while two amplified spots were detected in the CIN III lesions. Fourteen DNA spots were either reduced in their intensity or absent in cervical carcinomas as compared to their normal paired tissues. Reduction of intensity in 6 spots was observed in the 5 CIN III lesions. These genetic alterations may represent changes in cancer genes that are associated with human cervical carcinogenesis. Further characterization of these alterations may be significant to the understanding of cervical tumorigenesis and to the development of biomarkers for clinical trials in cancer chemoprevention.

Cervical human papillomavirus infection and intraepithelial neoplasia: a review

Cervical human papillomavirus (HPV) infections and intraepithelial neoplasias are precursors to cervical cancer, the second most common cancer in women worldwide. HPV satisfies the epidemiologic criteria for causality; the role of other cofactors is under study. Natural history studies show that most low-grade lesions (productive HPV infections) regress or persist, whereas high-grade lesions (those with integrated HPV DNA) progress. Immunobiologic studies demonstrate that infection peaks in the early 20s, leading to a 10- to 20-year period of persistent infection, before finally progressing to a preinvasive or invasive lesion. Papanicolaou (Pap) screening has lowered the morbidity and mortality from cervical cancer in every country in which screening programs have been introduced. The diagnostic strategy for an abnormal Pap smear includes colposcopy; the role of HPV DNA testing in screening or diagnosis remains unclear. Patients are treated with cervical ablation, cone biopsy, or chemopreventive agents. Efforts to strengthen screening and prevention, as well as new directions for research, are needed.

Development of a multivariate statistical algorithm to analyze human cervical tissue fluorescence spectra acquired in vivo

BACKGROUND AND OBJECTIVE

A general multivariate statistical algorithm has been developed to analyze the diagnostic content of cervical tissue fluorescence spectra acquired in vivo.

MATERIALS AND METHODS

The primary steps of the algorithm are to: (1) preprocess the data to reduce inter-patient and intra-patient variation of tissue spectra within a diagnostic category, without a priori information, (2) dimensionally reduce the preprocessed fluorescence emission spectrum with minimal information loss and use it to select the minimum number of the original emission variables of the fluorescence spectrum required to achieve classification with negligible decrease in predictive ability, and (3) assign a posterior probability to the diagnosis of each sample, so that samples with relative uncertain diagnosis can be reevaluated by a clinician. The algorithm was tested retrospectively and prospectively on cervical tissue spectra acquired from 476 sites from 92 patients at 337 nm excitation.

RESULTS

The algorithm based on the entire fluorescence spectrum differentiates squamous intraepithelial lesions (SILs) from normal squamous epithelia and inflammation with an average sensitivity and specificity of 88% +/- 1.4 and 70% +/- 1, respectively. The average sensitivity and specificity of the identical algorithm based on intensity selected at only two emission wavelengths is 88% +/- 1.4 and 71% +/- 1.4, respectively.

CONCLUSION

The multivariate statistical algorithm based on both types of spectral inputs at 337 nm excitation has a similar sensitivity and significantly improved specificity relative to colposcopy in expert hands.

Spectroscopic diagnosis of cervical intraepithelial neoplasia (CIN) in vivo using laser-induced fluorescence spectra at multiple excitation wavelengths

BACKGROUND AND OBJECTIVE

The diagnostic contribution of cervical tissue fluorescence spectra acquired in vivo at 380 and 460 nm excitation were analyzed using a general multivariate statistical algorithm.

MATERIALS AND METHODS

The primary steps of the algorithm are to: (1) preprocess data to reduce interpatient and intrapatient variation of tissue spectra from the same diagnostic category, without a priori information, (2) dimensionally reduce the pre-processed spectral data using Principal Component Analysis, and (3) develop a probability based classification scheme based on logistic discrimination using the diagnostically useful principal components. The algorithm was tested on cervical tissue spectra acquired from 165 sites at 380 nm excitation and from 147 sites at 460 nm excitation. A retrospective and prospective estimate of the algorithm's performance was determined.

RESULTS

At 460 nm excitation, (1) SILs can be differentiated from normal squamous tissues with an average sensitivity and specificity of 91% +/- 1.3 and 75.5% +/- 1, respectively; furthermore, (2) high grade SILs can be differentiated from low grade SILs with an average sensitivity and specificity of 80% +/- 4 and 76% +/- 5, respectively. In addition, using tissue spectra at 380 nm excitation, SILs can be differentiated from normal columnar epithelia and inflammation with an average sensitivity and specificity of 77% +/- 1 and 72% +/- 9, respectively.

CONCLUSIONS

Fluorescence spectra at multiple excitation wavelengths are essential for the detection and differential diagnosis of SILs at colposcopy.

Chemoprevention trials and surrogate end point biomarkers in the cervix

Cervical cancer is the second most common malignancy in women worldwide and remains a significant health problem for women, especially minority and underserved women. Despite an understanding of the epidemiologic risks, the screening Papanicolaou smear, and morbid and costly treatment, overall survival remains 40%. New strategies, based on the clinical and molecular aspects of cervical carcinogenesis, are desperately needed. Chemoprevention refers to the use of chemical agents to prevent or delay the development of cancer in healthy populations. Chemoprevention studies have several unique features that distinguish them from classic chemotherapeutic trials; these features touch on several disciplines and weave knowledge of the biology of carcinogenesis into the trial design. In the design of chemoprevention trials, four factors are important: high risk cohorts must be identified; suitable medications must be selected; study designs should include Phases I, II, and III; and studies should include the use of surrogate end point biomarkers. Surrogate end point biomarkers are sought because the cancer develops over a long period of time, and studies of chemopreventives would require a huge number of subjects followed for many years. Surrogate end point biomarkers serve as alternative end points for examination of the efficacy of chemopreventives in tissue. High risk cohorts include women with cervical intraepithelial neoplasia (CIN) or squamous intraepithelial lesions (SIL). Nutritional studies have helped define micronutrients of interest (folate, carotenoids, vitamin C, vitamin E). Other medications of interest include retinoids (4-hydroxyphenylretinamide [4-HPR], retinyl acetate gel, topical all-trans-retinoic acid), polyamine synthesis inhibitors (alpha-difluoromethylornithine [DFMO]), and nonsteroidal anti-inflammatory drugs (ibuprofen). Phase I chemoprevention studies of the cervix have tested retinyl acetate gel and all-trans-retinoic acid. Phase II trials of all-trans-retinoic acid, beta-carotene, and folic acid have been and are being carried out, whereas Phase III trials of all-trans-retinoic acid have been completed and have shown significant regression of CIN 2 but not CIN 3. Phase I studies of DFMO and Phase II studies of DFMO and 4-HPR are underway. Surrogate end point biomarkers under study include (1) quantitative cytology and histopathology; (2) human papillomavirus type testing; (3) biologic measures of proliferation, regulation, differentiation, and genomic instability; and 4) fluorescence spectroscopic emission. Clinical trials with biologic end points will contribute to our understanding of the neoplastic process and hence aid us in developing new preventive and therapeutic strategies.

Clear cell adenosquamous carcinoma of the cervix. An aggressive tumor associated with human papillomavirus-18

BACKGROUND

It is well recognized that adenocarcinomas and adenosquamous carcinomas of the cervix are frequently associated with human papillomavirus (HPV)-16 or -18. However, few studies have investigated associations between histologic variants of these tumors and specific types of HPV.

METHODS

Eleven cases of cervical adenosquamous carcinoma with an unusual histologic appearance were characterized using histochemical and immunohistochemical stains. Sections were tested for the presence of HPV DNA using the polymerase chain reaction (PCR) and type specific primers for HPV-16 and -18. Clinical outcome was determined from a chart review.

RESULTS

All tumors were histologically characterized by the presence of sheets of cohesive cells with prominent cell borders and a vacuolated or clear cytoplasm containing large amounts of glycogen. All tumors had focal gland formation and stained positive with mucicarmine stain. Using PCR, HPV-18 DNA was identified in all cases. The youngest patient was 24 years old and the oldest 74 years (mean, 43 years). Eight (73%) of the 11 patients have developed recurrent disease with a mean follow-up until recurrence of 9.5 months (range, 3-22 months). Seven (64%) of the 11 patients have died of their cervical tumors. Of the five patients with Stage IB disease, three (60%) have died of their cervical tumors.

CONCLUSIONS

A subset of invasive cervical adenosquamous carcinoma associated with HPV-18 that has a distinctive histologic appearance and an aggressive clinical course is described. The term "clear cell adenosquamous carcinoma" is proposed for this unique variant of invasive cervical carcinoma.

Staging laparotomy for endometrial carcinoma: assessment of retroperitoneal lymph nodes

The surgical staging scheme for uterine corpus cancer adopted in 1988 by the International Federation of Gynecology and Obstetrics assigns patients with tumor spread to retroperitoneal lymph nodes to stage IIIC. However, a recommended approach to the detection of lymph node metastasis is not delineated. As part of an ongoing project to assess the value of surgical staging procedures, we reviewed the techniques of lymph node evaluation in 295 at-risk patients. Cases included clinical stage I patients whose preoperative biopsies demonstrated grade 2 or 3 adenocarcinoma or papillary serous, clear cell, or mixed carcinoma. We arbitrarily divided the retroperitoneal space into 10 lymphatic zones: left and right para-aortic, common iliac, external iliac, hypogastric, and obturator. Eighty-two percent of patients had some type of node sampling that involved a mean of three zones. Thirty-three of 244 sampled cases (13.5%) had nodal metastases: 20 had gross involvement and 13 had microscopic. We stratified patients into three groups: (1) those who had no node sampling (n = 51), (2) those with some nodes biopsied (n = 193), and (3) those whose node sampling included a minimum of one para-aortic plus at least one right and left pelvic specimen (n = 51). Retroperitoneal recurrences thought to originate from lymph node sites were identified for the "node-negative" patients in each group: Group 1, 4/51 (8%); Group 2, 9/173 (5%); and Group 3, 0/38 (0%). Lymphatic site failures were seen in 8 of 33 (24%) patients with biopsy-proven metastases. We found that failure to systematically sample pelvic and para-aortic nodes results in a small, but real, risk of undetected extrauterine metastasis. A selective approach to sampling that includes biopsy from both para-aortic and bilateral pelvic lymphatic zones appears to provide an accurate estimate of true node negativity. Further evaluation of this approach is warranted.

The epidemiology of ovarian cancer

Ovarian cancer is the second most common cancer of the female reproductive system and the leading cause of death from gynecologic malignancies. In 1995, 26,600 women will be diagnosed with ovarian cancer in the U.S., and 14,500 women will die from the disease. Between 1986-1900, the overall age-adjusted incidence was 14.3/100,000 women; mortality was 7.8/100,000 women. Ovarian cancer, rare before age 40, increases steeply thereafter and peaks at ages 65-75. Incidence and mortality rates are higher among white women than among African-American women. Over the last three decades, ovarian cancer incidence has remained stable in high-risk countries, while an increasing trend has been reported in low-risk countries. Despite recent advancements in treatment, the overall five-year survival rates continues to be low (39%). Over 70% of ovarian tumors are diagnosed when regional or distant involvement has already occurred, causing survival rates to remain stable. The etiology of ovarian cancer is poorly understood. Most studies have focused on the epidemiology of invasive epithelial ovarian tumors, while few have explored the epidemiology of epithelial tumors of low malignant potential and nonepithelial tumors. Factors associated with an increased risk for invasive epithelial ovarian cancer include age, race, nulliparity, family history of ovarian cancer, and history of endometrial or breast cancer. Factors associated with a reduced risk are history of one or more full-term pregnancies, use of oral contraceptives, history of breast feeding, tubal ligation, and hysterectomy. Other factors such as infertility drugs, hormone replacement therapy, age at menarche, age at menopause, dietary factors, lactose intolerance, talc use, coffee and alcohol consumption have been suggested, but their role is still inconclusive.

Studies on in vivo induction of cytotoxic T lymphocyte responses by synthetic peptides from E6 and E7 oncoproteins of human papillomavirus type 16

Induction of cytotoxic T lymphocyte (CTL) responses is an important defense mechanism against infectious agents, specifically viruses. In the present investigation we employed a mouse assay system we previously developed, for rapid induction of CTLs by synthetic peptides from E6 and E7 oncoproteins of human papillomavirus type 16 (HPV-16). In particular, we compared the efficiency of CTL induction by HPV-16 peptides synthesized as linear monomers with those containing a dipalmitoyl-lysine-glycine-glycine (P2-KGG) moiety at the amino-terminus. Our results identified a 15-amino-acid peptide from E6(Q15L, aa 43-57) to be capable of inducing CTLs in vivo and addition of the lipid tail significantly increased CTL induction over that seen with the linear form of the peptide. Further, we identified a shorter peptide, V1OC, with 9 of 10 amino acids overlapping with Q15L peptide (aa 49-58) to be capable of inducing CTLs against both V1OC and Q15L. In case of E7 protein, our results demonstrated usefulness of P2-KGG moiety for enhanced CTL induction by previously identified CTL epitope peptides Q19D (aa 44-62) and R9F (aa 49-57). CTLs induced by both the E6 and E7 peptides were MHC class I-restricted and exhibited strict allele specificity and CD8+ phenotype. Our results showing enhanced cell-mediated immune responses with lipid-tailed forms of peptides add strength to the concept of a synthetic peptide-based vaccine for prophylaxis and therapy of HPV-associated cervical cancer.

Staging laparotomy for endometrial carcinoma: assessment of peritoneal spread

To evaluate surgical staging procedures in women with endometrial carcinoma, we examined the techniques used to assess the peritoneal cavity in 295 clinical stage I patients treated between 1985 and 1993. These patients were felt to be at increased risk for extrauterine disease because of significant myometrial invasion, high-grade (2 or 3), or variant histology (papillary serous, clear cell, or mixed). Patients had a mean of two intraperitoneal samples taken: 224 patients (76%) had at least an omental biopsy and peritoneal cytology. Additional peritoneal biopsy sites included pericolic gutters (50), pelvic peritoneum (45), bowel serosa/mesentery (24), diaphragm (22), appendix (11), and adhesions (7). At the time of staging laparotomy, 22 patients (7.5%) had gross evidence of peritoneal spread, which was readily confirmed by directed biopsy. In the 273 women without gross peritoneal disease, 3 (1%) had occult metastases detected by routine biopsy, 3 (1%) had microscopic metastases in palpably abnormal biopsies, and 22 had positive cytology as the only evidence of peritoneal disease. Only three operative complications were potentially attributable to peritoneal assessment: cystotomy (1), partial small bowel obstruction (1), and ileus (1). Peritoneal failures have been noted in 12 patients over a mean follow-up interval of 39 months. Seven of these patients had obvious peritoneal disease at laparotomy. Two of the remaining 5 had optimal peritoneal sampling and represent false-negative cases. A staging laparotomy that included total abdominal hysterectomy with adnexal resection, cytology, omental biopsy, and biopsy of grossly abnormal sites would have potentially identified all patients with known peritoneal disease. Routine biopsy of other grossly normal peritoneal sites is associated with extremely low yield and is not recommended.

Statistical techniques for diagnosing CIN using fluorescence spectroscopy: SVD and CART

A quantitative measure of intraepithelial neoplasia which can be made in vivo without tissue removal would be clinically significant in chemoprevention studies. Our group is working to develop such a technique based on fluorescence spectroscopy. Using empirically based algorithms, we have demonstrated that fluorescence is discriminating normal cervix from low- and high-grade cervical dysplasias with similar performance to colposcopy in expert hands. These measurements can be made in vivo, in near real time, and results can be obtained without biopsy. This paper describes a new method using automated analysis of fluorescence emission spectra to classify cervical tissue into multiple diagnostic categories. First, data is reduced using the singular value decomposition (SVD), yielding a set of orthogonal basis vectors. Each patient's emission spectrum is then fit by linear least squares regression to the basis vectors, producing a set of coefficients for each patient. Based on these coefficient values, the classification and regression tree (CART) method predicts the patient's classification. These results suggest that laser-induced fluorescence can be used to automatically recognize and differentially diagnose cervical intraepithelial neoplasia (CIN) at colposcopy. This method of analysis is general in nature, and can analyze fluorescence spectra of suspected intraepithelial neoplasms from other organ sites. As a more complete understanding of the biochemical and morphologic basis of tissue spectroscopy is developed, it may also be possible to use fluorescence spectroscopy of the cervix as a surrogate endpoint biomarker in Phase I and II chemoprevention trials.

Uterine neoplasms in patients treated with tamoxifen

Since 1985, when Killackey originally described three cases of endometrial carcinoma in patients receiving tamoxifen, there have been several reports confirming or denying the relationship between tamoxifen and endometrial carcinoma. Our study of 15 patients treated for breast carcinoma with tamoxifen found that papillary serous carcinoma was the most common tumor in this group of patients. Several other retrospective studies reported a high incidence of high-grade endometrioid adenocarcinoma or high-risk variants of endometrial carcinoma in patients receiving tamoxifen.

Inhibition of proliferation and induction of apoptosis in cervical carcinoma cells by retinoids: implications for chemoprevention

The effects of retinoids including all-trans-retinoic acid (ATRA), 13-CIS-RETINOIC ACID (13CRA), and N-(4-hydroxyphenyl)retinamide (4-HPR) on several cervical carcinoma cell lines in culture were investigated as a prelude to investigating the mechanisms underlying the chemopreventive potential of retinoids in cervical cancer. We found that when used at a concentration of 1 microM, 13CRA and ATRA inhibited the proliferation of three cell lines (ME-180 [HPV 68], SiHa [HPV 18], and HT-3 [HPV-]) by about 80% after a seven-day treatment. Three other cell lines (MS-751 [HPV 18], HeLa [HPV 18], C-33A [HPV-]) were moderately inhibited (30-48%), and two (C-4 II [HPV 18], CaSki [HPV 16]) responded poorly (< 25% inhibition). 4-HPR failed to inhibit the growth of any of these cell lines when used at 1 microM; however, when used at 5 or 10 microM, it induced apoptosis as evidenced by DNA fragmentation in several of the cell lines and was more potent in this effect than 10 microM ATRA. Retinoids that induce apoptosis in malignant cells may be able to exert similar effects on premalignant cells. Such retinoids would be expected to exhibit greater potency as chemopreventive agents than retinoids that exert only cytostatic effects.

Polyamines as biomarkers of cervical intraepithelial neoplasia

Polyamines (putrescine, spermidine and spermine) play critical roles in cell growth and transformation. Ornithine decarboxylase (ODC), key enzyme in polyamine biosynthesis, is considered a putative protooncogene crucial to the regulation of cell growth and transformation. Cancer patients have elevated levels of polyamines in their physiological fluids compared to normal counterparts. alpha-Difluoromethylornithine (DFMO), a specific suicide inhibitor of ODC, exhibits antitumor and antimetastasis activities, and displays effectiveness in many carcinogen-induced animal chemoprevention models. Therefore, we are using DFMO in a chemoprevention trial for cervical intraepithelial neoplasia grade III (CIN III), and evaluating patients for changes in polyamine metabolism as an intermediate marker of DFMO effect. A preliminary study showed that several milligrams of abnormal cervical biopsy tissue contained detectable levels of ODC activity and polyamines. Additionally, the presence of cadaverine suggested bacterial contamination of these tissues. For this reason, normal and abnormal biopsies collected during colposcopy were rinsed prior to frozen storage. In most patients, abnormal tissue showed greater ODC activities and lower spermidine/spermine ratios than normal tissues. Patients are now being treated with de-escalating doses of DFMO (1-0.06 g/m2/day) for one month. To study the effect of DFMO in patients with CIN III, we are collecting blood and cervical tissue specimens to measure the following parameters: plasma DFMO, ornithine and arginine levels; plasma N1-acetylspermidine levels; erythrocyte (blood polyamine carrier) free polyamine levels; cervical tissue free polyamine levels; cervical tissue N1-acetylspermidine levels; and cervical tissue ODC activities. N1-acetylspermidine will be examined as this compound is known to exist primarily in tumor tissues, not in normal tissues. We therefore established a high-performance liquid chromatography method for N1-acetylspermidine. We expect to find that polyamines are effective markers in analyzing DFMO effects in this chemoprevention trial, thus functioning as pharmacodynamic parameters as well as biomarkers for transformation.

In vivo diagnosis of cervical intraepithelial neoplasia using 337-nm-excited laser-induced fluorescence

Laser-induced fluorescence at 337-nm excitation was used in vivo to differentiate neoplastic [cervical intraepithelial neoplasia (CIN)], nonneoplastic abnormal (inflammation and human papilloma viral infection), and normal cervical tissues. A colposcope (low-magnification microscope used to view the cervix with reflected light) was used to identify 66 normal and 49 abnormal (5 inflammation, 21 human papilloma virus infection, and 23 CIN) sites on the cervix in 28 patients. These sites were then interrogated spectroscopically. A two-stage algorithm was developed to diagnose CIN. The first stage differentiated histologically abnormal tissues from colposcopically normal tissues with a sensitivity, specificity, and positive predictive value of 92%, 90%, and 88%, respectively. The second stage differentiated preneoplastic and neoplastic tissues from nonneoplastic abnormal tissues with a sensitivity, specificity, and positive predictive value of 87%, 73%, and 74%, respectively. Spectroscopic differences were consistent with a decrease in the absolute contribution of collagen fluorescence, an increase in the absolute contribution of oxyhemoglobin attenuation, and an increase in the relative contribution of reduced nicotinamide dinucleotide phosphate [NAD(P)H] fluorescence as tissue progresses from normal to abnormal in the same patient. These results suggest that in vivo fluorescence spectroscopy of the cervix can be used to diagnose CIN at colposcopy.