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G Grazzini

Publications and source records attributed to G Grazzini.

At least 19 recordsLinked to original sources
PubMed2002

Basic variables at different positivity thresholds of a quantitative immunochemical test for faecal occult blood.

OBJECTIVES: Screening by faecal occult blood testing (FOBT) is effective in decreasing mortality and incidence of colorectal cancer (CRC). Immunochemical tests have proved to be more cost effective than guaiac FOBTs. The latex agglutination test (LAT) has the advantage of being a fully automated, quantitative test. The aim of this study is to interpret the overall experience with LAT according to different positivity thresholds. SETTING: A population based screening programme is currently running involving subjects aged 50-70, invited every 2 years to have an FOBT. LAT is the standard screening test and has a positivity threshold for further diagnostic tests of 100 ng haemoglobin/ml of sample solution. METHODS: Positivity rates, detection rates for CRC high risk adenomas, and positive predictive values for CRC, high risk adenomas, and low risk adenomas were calculated for several positivity thresholds. RESULTS: 19,132 attendances at screening were recorded (11,774 at first screening, 7358 at subsequent screenings). Progressively increasing the positivity threshold from 100 to 200 ng/ml showed (a) a decrease in positivity rate; (b) a decrease in detection rates for CRC or high risk adenomas; (c) an increase in positive predictive values for cancer; (d) an increase in positive predictive value for high risk adenomas. CONCLUSIONS: Increasing the positivity threshold of the LAT reduces recall rate and improves positive predictive value for cancer or high risk adenomas but substantially decreases the detection rate of CRC and high risk adenomas. For this reason increasing the positivity cut off for LATs is not advisable. On the other hand decreasing the positivity threshold would increase recall rate and sensitivity of screening. Careful evaluation of sensitivity of the quantitative results of the LAT for interval cancers is needed to definitively assess the optimal positivity threshold for LATs in population based screening programmes.

Adenoma↗
PubMed2001

Measuring interval cancers in population-based screening using different assays of fecal occult blood testing: the District of Florence experience.

The fecal occult blood test (FOBT) has demonstrated its efficacy in reducing mortality from colorectal cancer (CRC). The guaiac-based FOBT has been criticized for its low sensitivity. In this study, two different assays for FOBT (guaiac or an immunochemical test based on reversed passive hemagglutination [RPHA]) were tested for comparison within a population-based screening program for colorectal cancer in the province of Florence (Italy). The proportional incidence method was used to calculate sensitivity for both FOBTs, according to rank of screening (first or repeat), age at entry (two groups of 50 to 59 and 60 to 70 years old) and lesion site (colon or rectum). When comparing FOBTs, the sensitivity multivariate Poisson regression was used to adjust for other variables. The sensitivity after the first 2 years was 50% (95% confidence interval [CI] 34% to 63%) for the guaiac test versus 82% (95% CI 67% to 92%) for RPHA. At multivariate analysis the risk of developing an interval cancer after a guaiac test is almost 3 times that after RPHA (rate ratio = 2.64; 95% CI 1.3 to 5.4). Our study confirms that RPHA is more sensitive than the guaiac test. The assumption that FOBT screening for CRC has to be based on a guaiac test should be reconsidered, and RPHA should be recommended as the standard FOBT for screening purposes.

Aged↗
PubMed2000

Screening for colorectal cancer by faecal occult blood test: comparison of immunochemical tests.

OBJECTIVE: To compare two immunochemical faecal occult blood tests based on reversed passive haemagglutination (RPHA) or latex agglutination (Hdia) in a population based screening setting. METHOD: Hdia was interpreted according to three positivity thresholds: 100, 150, or 200 ng of haemoglobin/mg of specimen solution. A total of 5844 subjects were recruited into the study, from 17432 invited subjects aged 50-70. RESULTS: Positivity rates were 3.3% for RPHA, Hdia100 3.5%, Hdia150 2.5%, Hdia200 2.0%. Among subjects complying with the diagnostic work up, colorectal cancer (CRC) was detected in 19 subjects (17 RPHA positive, 16 Hdia100 positive, 15 Hdia150 positive, 14 Hdia200 positive) and high risk adenoma/s in 41 subjects (28 RPHA positive, 32 Hdia100 positive, 29 Hdia150 positive, 25 Hdia200 positive). The prevalence of screen positive CRC in the population was for RPHA 2.9 per thousand, Hdia100 2.7 per thousand, Hdia150 2.6 per thousand, Hdia200 2.4 per thousand. The prevalence of screen positive high risk adenomas in the population was for RPHA 4.8 per thousand, Hdia100 5.5 per thousand, Hdia150 5.0 per thousand, Hdia200 4.3 per thousand. CONCLUSION: Hdia100 was as sensitive as RPHA for cancer and high risk adenomas. As Hdia is less technically complex than RPHA, it is a valid alternative to the latter, provided that full automation of the development procedure is available. Increasing the positivity threshold of Hdia up to 150 or 200 ng of haemoglobin/mg of specimen solution is not advisable as the increase in specificity is too small to justify the corresponding decrease in the detection of screen positive cancers in the population.

Adenoma↗
PubMed1997

Effect of faecal occult blood testing on colorectal mortality: results of a population-based case-control study in the district of Florence, Italy.

The aim of our case-control study was to estimate the effect on mortality from colorectal cancer (CRC) of a population-based screening with a faecal occult blood test started in 1982 in a rural area of the district of Florence. We examined the relationship between mortality and the interval since the most recent screening. The cases in the study were 206 individuals who had died from CRC after the age of 41 years. Five controls were selected randomly from the list of individuals alive at the time of diagnosis of the corresponding case and were matched by sex, age and place and length of residence. After adjustment for potentially confounding factors, the odds ratio (OR) for death from CRC for screened persons vs. those not screened was 0.60 [95% confidence interval (CI), 0.4-0.9]. The OR was lowest in the first 3 years after the most recent test (OR = 0.54; 95% CI, 0.3-0.9) and increased towards unity subsequently. Our results suggest that screening for CRC by biennial faecal occult blood testing can reduce mortality from the disease.

Aged↗
PubMed1997

Cost analysis in a population based screening programme for colorectal cancer: comparison of immunochemical and guaiac faecal occult blood testing.

OBJECTIVE: To compare the costs of colorectal cancer (CRC) screening by two faecal occult blood tests (FOBT)-namely, Hemoccult (guaiac based) and reversed passive haemagglutination (RPHA) tests. RPHA was interpreted according to two positivity thresholds (+ or +/-). METHODS: Attenders performed both tests. Subjects with a positive FOBT test were invited to have a complete exploration of the colon. The total costs for every 10,000 screened subjects and costs for each unit of result (screened subject, or patient with adenoma/s or cancer detected) were calculated for both tests. RESULTS: 8353 subjects were enrolled. A total of 2109 repeated screening after two years. RPHA(+ and +/-) showed the highest and RPHA(+) the lowest positivity rate at first screening. The Hemoccult positivity rate was highest at repeat screening. Total costs of screening by RPHA(+ and +/-) were highest as this method had the highest recall rate. Screening by RPHA(+) was the least costly. Costs for each screened subject were highest for RPHA(+ and +/-) and lowest for RPHA(+). Costs for each cancer detected were lowest for RPHA(+) and highest for Hemoccult or RPHA(+ and +/-) in subjects aged > 49 or < 50, respectively. Costs for subjects with detected adenoma/s of > 9 mm were lowest for RPHA(+ and +/-) and highest for Hemoccult. At repeat screening total costs of RPHA(+ and +/-) were lower than at first screening, whereas for each subject with cancer or adenoma/s costs were increased. CONCLUSIONS: Our data confirm that screening by RPHA is more cost effective than by Hemoccult.

Adult↗
PubMed1996

Screening by ultrasonography for endometrial carcinoma in postmenopausal breast cancer patients under adjuvant tamoxifen.

Seven-hundred thirty-seven asymptomatic postmenopausal breast cancer patients under long-term adjuvant tamoxifen therapy (average, 50 months) were screened by endometrial ultrasonography. Abnormal endometrial thickness (6 mm or larger) was observed in 209 subjects and was significantly associated with patients' age and duration of tamoxifen therapy. Outpatient endometrial biopsy was recommended in presence of abnormal endometrial thickness: 25 subjects refused biopsy, whereas 76 were not biopsied because of cervical stenosis and were followed-up by repeat sonography. Of 108 biopsied subjects, one case of endometrial carcinoma (as expected in the screened cohort according to age-specific incidence rates provided by the regional cancer registry) and one case of endometrial hyperplasia were histologically confirmed, whereas endometrial atrophy was evident in the remaining cases. No other case of endometrial carcinoma has been recorded so far in the studied cohort according to the local cancer registry and no further change of the endometrium has been observed at sonographic follow-up. The cohort will be followed-up by repeat annual endometrial sonography. Thus far, we did not find evidence of increased prevalence of endometrial pathology (carcinoma or hyperplasia) which may be ascribed to tamoxifen therapy. The apparent increase in endometrial thickness observed at sonography might be explained by tamoxifen-induced changes of endometrial stroma and myometrium, misinterpreted as hyperplasia, while causing no real epithelial disease.

Aging↗
PubMed1996

Immunochemical vs guaiac faecal occult blood tests in a population-based screening programme for colorectal cancer.

Two faecal occult blood tests (FOBTs), Hemoccult II (guaiac based) and Hemeselect (immunochemical) were compared in a population screening for colorectal cancer on 24 282 subjects aged 40-70. Hemeselect was interpreted according to a lower (+ and +/-) and a higher (+) positivity threshold. A total of 8008 compliers were enrolled in the study. Positivity rates: Hemoccult = 6.0%, Hemeselect (+ and +/) = 8.2%, Hemeselect (+) = 3.1%. Among FOBT-positive subject complying with the diagnostic work-up, 22 had colorectal cancer (17 Hemeselect-positive (+), four Hemeselect-borderline (+/-), 15 Hemoccult-positive) and 166 subjects had adenomas (62 Hemeselect(+), 56 Hemeselect-borderline (+/-), 79 Hemoccult-positive) were detected. The positive predictive values (PPVs) for cancer were as follows: Hemoccult = 3.7%, Hemeselect (+ and +/-) = 3.8%, Hemeselect (+) = 8.4%. The PPVs for adenoma(s) were: Hemoccult = 19.7%, Hemeselect (+ and +/-) = 21.4%, Hemeselect (+) = 30.5%. The specificity for cancer was: Hemoccult = 94.1%, Hemeselect (+ +/-) = 92%, Hemeselect (+) = 97.1%. Ratios between detection rates of each test and expected incidence of colorectal cancer suggest that Hemoccult anticipates cancer diagnosis by approximately 2 years on average whereas the mean diagnostic anticipation of Hemeselect ranges between 2.5 and 3.2 years. Hemeselect is superior to Hemoccult as it is at least as effective but more efficient and acceptable than guaiac testing. Further evaluation of Hemeselect cost-effectiveness and sensitivity is needed in order to assess the optimal threshold of positivity and screening frequency.

Adult↗
PubMed1995

Trends in cervical cancer incidence in the district of Florence.

The trend in cervical cancer incidence in the District of Florence from 1975 to 1989 was investigated. Tuscany Cancer Registry data were available since 1985. Incidence data from 1975 to 1985 were obtained through a retrospective survey of all the Departments of Pathology and Gynaecology in the district. Cytological screening for cervical cancer has been available in the district since 1973, and since 1980 active invitation of residents aged 25 to 59 years has been in use. A significant trend in decreasing incidence was evident for the overall population (P = 0.003) and for 40-49 (P = 0.028), 50-59 (P < 0.001) and 60-69 (P = 0.002) year age groups, whereas no significant trend was observed for the age group 30-39 years. An association between attendance to screening and reduced incidence was evident, in that a greater reduction was evident for those cohorts (ages 50-59 and 60-69) who had a higher compliance to screening 10-15 years before. If the decrease in cervical cancer incidence was spontaneous, a parallel decrease of CIN3, which is commonly assumed to be the precursor of invasive carcinoma, would be expected. On the contrary, the detection rate of CIN3 at first Pap test showed a significant increase in the study period. All these findings suggest that the observed reduction in cervical cancer incidence was mostly due to the effect of screening, and stress the need for optimising the coverage of the invited population.

Adult↗
PubMed1994

Comparative analysis of results of guaiac and immunochemical tests for faecal occult blood in colorectal cancer screening in two oncological institutions.

The performances of three faecal occult blood tests, rehydrated Hemoccult (HOR), Hemoccult sensa (HOS) and Hemeselect (HSEL) on 3 days were compared in 1,725 subjects consecutively recruited in two oncological institutions in Milan and Florence. Significant differences between the results were evident as far as HOR positivity rates (7.5% vs 4.0%, respectively) and specificity (94.3% vs 97.5%, respectively) are concerned. Overall positivity rates of HOR, HOS and HSEL were 5.9%, 5.4% and 12%, respectively; significant differences were evident between HSEL and each of the two guaiac tests. Cancer was detected in eight subjects, adenoma/s in 47. Specificity estimates were 95.8%, 90.2% and 90.5% for HOR, HOS and HSEL, respectively; significant differences were evident between HSEL and the other two tests. No significant difference between tests was evident for sensitivity or positive predictive values for cancer or adenomas. In the CSPO (Florence) population (1,223 subjects; five with cancer, 16 with adenoma/s) the performances of 1-day HSEL testing were determined on the basis of the first faecal sample only and compared with 3-day HOR, HOS and HSEL testing. The positivity rates of 1-day HSEL, 3-day HOR, HOS and HSEL testing were 7.0%, 5.0%, 5.5% and 12.9%, respectively. Only 3-day HSEL positivity rate was significantly higher than 1-day HSEL. One-day HSEL specificity (94.9%) was significantly higher than 3-day HSEL (90.0%), whereas no significant difference was seen between 1-day HSEL, HOR (96.5%), and HOS (96.1%) specificity. No significant difference between tests is evident in the CSPO population as far as positive predictive values and sensitivity for cancer and adenomas are concerned.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1993

Screening history of incident cases of invasive carcinoma of the cervix. Florence district 1988-1989.

BACKGROUND: Incidence cases of carcinoma of the cervix may be assumed as failures of a population-based cytologic screening program. Monitoring such cases would provide an estimate of screening effectiveness, and evaluating the causes of the failures would improve screening performance. STUDY DESIGN: All incident cases of cervicocarcinoma registered in 1988 and 1989 in the Tuscany Tumor Registry were eligible for the study and were reviewed. RESULTS: Sixty-nine eligible cases were considered. Non- or irregular attendance (negative smear-to-diagnosis interval > 5 years) for the Pap smear was recorded in 53 subjects. A false-negative smear (smear-to-diagnosis interval < 5 years) and refused or inadequate assessment/treatment at private practices or local hospitals were recorded in 12 cases. False-negative smears by the local screening program were recorded in 4 cases only. CONCLUSIONS: Non- or irregular attendance was the major cause of screening failures. Since cytologic screening or diagnostic assessment outside the screening program may be inadequate, central screening and follow-up is recommended. Non-attenders showed a strong negative attitude towards screening, and general practitioners and gynecologists need to be further stimulated for systematic screening promotion. Immediate evaluation of the screening history of incident cases of cervicocarcinoma should be mandatory in any screening program.

Adult↗
PubMed1993

Testing cervicography and cervicoscopy as screening tests for cervical cancer.

AIMS AND BACKGROUND: Suboptimal sensitivity is currently reported for Pap test in screening for cervical cancer. Colposcopy is known to be more sensitive than cytology but its use as a screening test is not possible due to costs and complexity. Screening by cervicography has been suggested as a compromise being less costly and feasible. The present study evaluates the feasibility of screening by cervicography and cervicoscopy (naked eye examination of the cervix after acetic acid lavage) on a consecutive screening series. METHODS: Cervicography and cervicoscopy were performed by the smear taker in subjects consecutively attending a screening clinic. Women with abnormal cytology (atypia or more severe lesion) and/or abnormal cervicography or cervicoscopy (acetowhite lesion) underwent colposcopic assessment. The three screening methods were compared according to positivity rate, CIN 2-3 detection rate and positive predictive value. RESULTS: 2105 consecutive subjects were screened. Positivity rate was 3.8%, 15.3% or 25.4% for cytology, cervicography or cervicoscopy, respectively, 486 of 555 women attended the assessment phase, 281 directed biopsies were performed and 8 CIN 2-3 lesions were detected. Cytology, cervicography and cervicoscopy, detected 5.5, or 7 of 8 CIN 2-3 lesions, respectively. The positive predictive value was 0% for cytologic atypia, 25% for cytologic SIL, 1.75% for cervicography and 2.05% for cervicoscopy. Detecting one CIN 2-3 lesion at cytology cost $5,543. The cost per each additional cytologically negative CIN 2-3 lesion detected at cervicography or cervicoscopy was $12,947 or $3,916, respectively. CONCLUSIONS: The study confirms the limited sensitivity of cytology for CIN 2-3. The association of cervicography was not cost effective. Cervicoscopy was poorly specific but increased the detection rate of CIN 2-3 at relatively low costs. Cervicoscopy is worth further evaluation as a screening test.

Adolescent↗
PubMed1993

Effect of rehydration on guaiac-based faecal occult blood testing in colorectal cancer screening.

Screening for colorectal cancer by means of unhydrated Hemoccult (HO) is in progress in the Province of Florence since 1982. In 1990 rehydrated HO was introduced in the town of Empoli. Five adjacent municipalities where screening had started in 1987 were selected for comparison. In both areas subjects aged 40-70 were invited by mail to undergo the screening protocol. HO-positive subjects were invited to undergo either pancolonoscopy or a combination of left colonoscopy and double contrast barium enema. HO-negative subjects were invited to repeat screening 2 years later. The positivity rate of HO was significantly higher (P < 0.001) for rehydrated (5%) as compared to unhydrated (3.1%) HO. The positive predictive values for cancer (unhydrated: 5.8%; rehydrated: 8.9%) and for adenomas (unhydrated: 26.7%; rehydrated: 25.5%) did not significantly differ. The detection rates of rehydrated HO were significantly higher as compared to unhydrated HO both for cancer (0.37% vs 0.15%; P < 0.05) and adenomas (1.06% vs 0.72%; P < 0.05%). In the present experience rehydration doesn't produce any decrease in the positive predictive value for cancer or adenomas and the increase in the positivity rate appears quite acceptable when considering the significant increase in the detection rates of cancer and adenomas. We conclude that rehydrated HO should be introduced as the standard test for screening in order to increase sensitivity for colorectal cancer and adenomas.

Adenoma↗