Follow-up and final results of the Oslo I Study comparing screen-film mammography and full-field digital mammography with soft-copy reading.

PURPOSE: To compare cancer detection rates of screen-film (SFM) and full-field digital mammography (FFDM) with soft-copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false-negative FFDM interpretations. MATERIAL AND METHODS: Using a paired study design, 3683 women underwent SFM and FFDM in a population-based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5-point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5-point rating scale. SFM-positive cases were discussed in a SFM consensus meeting and FFDM-positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen-detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed-rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. RESULTS: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P=0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P=0.21). Of the 10 interval cancers and 16 screen-detected cancers in the subsequent round, 3 had true-positive SFM scores while 4 had true-positive FFDM scores in the initial reading session. A total of 38 cancers therefore had a positive result at double reading at one or both modalities, 31 at SFM and 27 at FFDM (McNemar test, P=0.48). Comparison of SFM and FFDM interpretations using the mean score for each case revealed no statistically significant difference between the two modalities (Wilcoxon signed-rank test for matched pairs; P-value=0.228). Two initial round cancers (one tumor found incidentally at work-up for a mass proved to be a simple cyst with a positive score at FFDM but a negative score at SFM, and one tumor with positive score at SFM but negative score at FFDM due to positioning failure) were excluded from the further analysis. Excluding these two cancers from comparison, there were 31% (22 of 72) false-negative SFM and 47% (34 of 72) false-negative FFDM individual interpretations. The overall mean interpretation time for normal FFDM examinations was 45 s. For most false-negative FFDM results, the reading time was shorter or longer than for normal examinations. The recorded FFDM interpretation time was noticeably short for several overlooked cancers manifesting as microcalcifications (ductal carcinoma in situ). CONCLUSION: There is no statistically significant difference in cancer detection rate between SFM and FFDM with soft-copy reading in a mammography screening program. Analysis of cancers missed at FFDM with soft-copy reading indicates that close attention has to be paid to systematic use of image display protocols.

Diagnostic value of ultrasonography in patients with palpable mammographically noncalcified breast tumors.

PURPOSE: To analyze the diagnostic accuracy of mammography, ultrasonography (US), and both methods combined in evaluation of palpable noncalcified breast tumors. MATERIAL AND METHODS: Mammograms and sonograms of 200 patients with palpable noncalcified breast masses were retrospectively analyzed independently by four experienced radiologists in 3 sessions: Mammography or US interpretations in the first two and combined reading in the last session. Nonneoplastic abnormalities and mammographically obvious cancers were excluded. Receiver operating characteristic (ROC) analyses were performed for 115 (60 benign and 55 malignant) tumors and subgroups according to tissue density and tumor size. A single ROC curve for each diagnostic test was obtained by pooling the individual ratings. The area under the ROC curve was used as a measure of diagnostic performance. RESULTS: US revealed significantly higher diagnostic performance than mammography for tumors larger than 2 cm. Combined reading showed significantly higher performance than mammography except for tumors smaller than 2 cm. The performance of all three tests was reduced in dense parenchyma, and significantly so for mammographic and combined interpretation. CONCLUSION: The accuracy of US in patients with palpable mammographically noncalcified and not obviously malignant breast tumors is lower than reported for mixed sample populations. The accuracy of US may be influenced by breast parenchyma density. Combined reading offers the highest diagnostic accuracy.

Variability in the interpretation of ultrasonography in patients with palpable noncalcified breast tumors.

PURPOSE: To analyze interobserver variability of ultrasonography (US) as an adjunct to mammography in patients with palpable noncalcified breast tumors. MATERIAL AND METHODS: Mammographic, US, and combined reading of 200 patients with palpable noncalcified breast masses were performed independently by four experienced radiologists. Nonneoplastic abnormalities and mammographically obvious cancers were excluded. Receiver operating characteristic (ROC) analysis based on 115 tumors was carried out for mammography, US, and both combined for each radiologist. The US diagnoses of the 45 cancers excluded from ROC analysis and the 55 cancers included were compared. RESULTS: One radiologist revealed a significantly higher diagnostic performance with US than with mammography. Combined reading showed the highest performance for all observers, but the improvement as compared with mammography was significant for only two. Higher accuracy on combined reading was mainly caused by correct upgrading of tumors with benign or indeterminate mammographic findings. One radiologist had benefit of US for downgrading of tumors. All four radiologists made a malignant US diagnosis twice as often in mammographically obvious cancers than in mammographically nonconclusive tumors. CONCLUSION: Radiologists differ substantially in interpretation of breast imaging. Combined reading offers the highest diagnostic accuracy mainly by correct upgrading of tumors on US. The role of US for downgrading tumors is operator-dependent.

Inherited predisposition to breast carcinoma. Results of first round examination of 537 women at risk.

Five hundred and thirty seven women at risk for breast carcinoma were identified. Family history was detailed and each woman given genetic counselling. Diagnostic examination for breast carcinoma was performed at the major hospitals of Norway, and included physical examination by expert surgeon, mammography and/or ultrasonography, and fine needle aspiration cytology when appropriate. Altogether 8 carcinomas and 5 cases of atypical hyperplasia were found, compared with 1.6 and 0.3 expected, respectively, from population studies. The finding exceeded the expected numbers described by autosomal dominant inheritance. In addition we found one carcinoma in situ. It is concluded that the methods employed are suitable to identify and examine women at risk for breast carcinoma. It is suggested that atypical hyperplasia may be the precancerous lesion, and should be treated as such.

Subjective evaluation of image quality based on images obtained with a breast tissue phantom: comparison with a conventional image quality phantom.

A breast tissue phantom was used for assessment of mammographic image quality. Three images, exposed to give a reference area film density of 1.25 +/- 0.03, were obtained for each of five different film/kV combinations. Each of three radiologists carried out a series of three blind readings, in which the 15 films were ranked according to sharpness and contrast. In a similar experiment with a conventional image quality phantom, scores for the visualization of simulated calcifications and contrast-detail performance, and measures for resolution and contrast were obtained. In both experiments, the judgements of the readers were highly consistent, and both the intraobserver and interobserver variabilities were non-significant. No significant differences between the film/kV combinations were found with respect to high-contrast resolution and visualization of the simulated calcifications. The contrast measures obtained with the conventional phantom correlated well with the contrast scores obtained with the breast tissue phantom. The contrast-detail scores obtained with the conventional phantom showed no correlation with the scores obtained with the breast tissue phantom, nor with the contrast measures obtained with the conventional phantom.

Physicians' opinions and use of controversial technologies. The case of mammographic screening in Norway.

In a survey of 196 Norwegian radiologists and 37 breast imaging centers, physicians' preferences were found to be likely to influence the use of mammography. In their decision making, the radiologists appear to be influenced by income motives and by perceptions of the risk of misdiagnosing breast cancer. Despite opinions favorable to mammographic screening, most radiologists would prefer a CT scanner or a magnetic resonance imaging unit to a mammographic unit if the x-ray department were in a position to acquire capital equipment.

[Utilization of mammography--who will come and why?]. / Bruk av mammografitilbud--hvem kommer og hvorfor?

Mammography has been used to detect early stages of breast cancer in women over the age of 40 years. Nationally organized mammography screening has not been initiated in Norway, but women have the possibility of undergoing mammography at many hospitals and private institutions. This article describes the use of mammography at Røntgensenteret, a private institute, from January to July 1992. Women in the age group 40 to 50 years were the most frequent users. The most important reason for the women undergoing mammography was a recommendation from their physician. Living near to the examination unit was also an important factor.

Prediction of treatment temperatures in clinical hyperthermia of locally advanced breast carcinoma: the use of contrast enhanced computed tomography.

PURPOSE: Nineteen patients with locally advanced breast carcinoma were subjected to computed tomography examinations prior to thermoradiotherapy. Pre- and postcontrast computed tomography images were obtained, and tumor contrast enhancement was studied in relation to tissue perfusion, PERF, and steady state temperature, TS, in an attempt to develop an assay for prediction of treatment temperatures in clinical hyperthermia of breast carcinoma. METHODS AND MATERIALS: PERF and TS were calculated from temperature data achieved during the first fraction of the heat treatment regimen. The computed tomography images were subjected to image analysis, and two parameters representing tumor contrast enhancement were calculated from the computed tomography numbers; the absolute increase in mean attenuation, delta N, and the fraction of the postcontrast attenuation values that was higher than the mean precontrast attenuation value, F+C. RESULTS: delta N and F+C were clearly correlated to each other. The two parameters differed considerably among the patients, showing that the accumulation of contrast medium was higher in some tumors than in others. Tumor contrast enhancement increased with increasing PERF, suggesting that the accumulation of contrast medium in the tumors was determined mainly by the effective tissue perfusion. There was also a clear correlation between tumor contrast enhancement and TS. The tumors showing a high accumulation of contrast medium were more difficult to heat than those showing a low accumulation. CONCLUSION: The results indicate that contrast enhanced computed tomography images may give information about the treatment temperatures that can be achieved in clinical hyperthermia of breast carcinoma. The computed tomography images may possibly be used to predict those tumors that can be heated to therapeutic temperatures.

[Local recurrence of breast cancer after breast preserving surgery. Experiences with a triple test as a routine control]. / Lokalt residiv av cancer mammae etter brystbevarende behandling. Erfaringer med trippeldiagnostikk som kontrollrutine.

Patients treated for breast cancer with breast-conserving surgery and radiotherapy were followed up by physical examination, mammography, and fine needle aspiration ("triple test") at The Norwegian Radium Hospital. Local recurrence was found in six cases. Two recurrences were detected by physical examination only, one by physical examination and mammography, and three by mammography only. Fine needle aspiration is useful when recurrence of cancer is suspected at mammographic or physical examination. Follow-up after breast-conserving treatment requires considerable experience in the field. Follow-up using the "triple test" should take place at regional centres.

[Mammographic findings after breast-preserving procedure]. / Mammografifunn etter brystbevarende behandling.

Clinical evaluation of the breast after breast-conserving surgery and postoperative irradiation for carcinoma is made difficult by the changes induced by the treatment. Therefore mammographic evaluation, comprises an important part of the follow-up of these patients. The interpretation of the mammograms requires knowledge of the changes expected to occur after treatment. In this paper we describe such changes as experienced in our department.

[Mammography--watch out for false negatives]. / Mammografi--husk de falskt negative.

Patients with breast tumours should be examined by a combination of physical examination, mammography and fine needle aspiration biopsy. The authors discuss the history of four patients with palpable breast lesions. All of these patients had tumours which had not been discovered by mammography. The diagnosis was delayed 2,11,12 and 12 months respectively. Patients with palpable lesions must not be referred to mammography performed under "screening conditions", but must be examined in a clinical context, preferably by the "triple-test".

Features of irradiated urinary bladder tumors and their correlation with malignancy observed on computed tomography.

CT features of 42 masses in the bladder wall were characterized and subjected to analysis to find indicators of malignancy. A CT technique with thin slices and intravenous contrast medium was used. Multiple regression and multivariate analysis showed good ability of contrast-enhanced CT to discriminate between benign and malignant masses in the bladder wall. Protrusion of a mass into the perivesical fat had some importance in discriminating between malignant tumors with and without perivesical growth although the detection of perivesical growth was less certain.

[Contrast mammography in spontaneous bloody secretion from the nipple]. / Kontrastmammografi ved spontan blodig sekresjon fra mammae.

43 women with spontaneous bloody nipple discharge were examined by galactography performed with water soluble contrast medium. The purpose of this study was to evaluate the use of galactography in these patients, to localize the cause of this particular type of discharge and to register the therapeutic consequences of the findings. Surgical resection was carried out in all cases where galactography showed intraductal pathology. The remaining patients (except for four who also underwent surgery) were observed without treatment. No sign of carcinoma was found in a follow-up examination of the non-operated patients after two to four years. The results show that galactography can be suitably used to demonstrate and localize intraductal pathology, and may therefore be of importance in the preoperative investigation of spontaneous blood-stained secretion.

Computed tomography of the urinary bladder shortly after radiation therapy for rectal carcinoma.

Eighteen patients with rectal carcinoma were examined with computed tomography (CT), before and shortly after preoperative irradiation. Changes in the bladder that could be mistaken for tumor growth did not occur at CT. However, considerable individual variations were seen. Radiation therapy did not result in increased contrast enhancement of the bladder wall after irradiation. The bladder wall thickness increased somewhat during and after treatment and the bladder volume was reduced. Localized thickening with little contrast enhancement was seen in the anterior bladder wall in 3 patients. One case of irradiation cystitis was noted. Edema was seen in the perivesical fat, but could in no case be mistaken for tumor growth.

Positioning of temperature measurement points using multiplanar computed tomography.

A method is described for the use of computed tomography and multiplanar reconstruction to depict in single images the full course of obliquely running thermometry catheters. In 14 patients given thermoradiotherapy for locally advanced breast carcinoma, reformatted images of the full catheter course were obtained for all 98 catheters so far tested. The main clinical advantage of this time-consuming procedure was the ability to determine the localization within the catheters of individual temperature measurement points of multipoint thermistor probes. It was also possible to study the localization of the measurement points in relation to the tumour margins.

Cisplatin and medium dose methotrexate in advanced transitional cell carcinoma of the urinary tract.

Twenty-seven patients with advanced transitional cell carcinoma of the urothelium were studied. The area of each tumour was measured by computed tomography. Twenty-four of the 27 patients were evaluated after treatment with the following course of chemotherapy given intravenously: day 1-cisplatin 50 mg/m2; day 2-methotrexate 250 mg/m2; and folinic acid rescue treatment 24 hours after the methotrexate infusion. Each cycle of treatment was given three times, with two weeks between cycles. There were two complete and 11 partial responses, and the primary tumour responded as often as the distant metastases. The toxicity of the regimen was acceptable, even given the advanced age of most of the patients. Most of whom found that their disturbances of micturition and sleeping problems were improved by the treatment. Cisplatin combined with methotrexate achieves a response rate of about 50% in advanced transitional cell carcinoma. When combinations of chemotherapy are being chosen for these often elderly patients the curability and palliation effects must be balanced against the toxicity and morbidity.

Absorbed dose resulting from a specially designed computed tomography technique for examination of the urinary bladder.

The absorbed spatial dose distribution resulting from a specially designed CT protocol for examination of the urinary bladder has been investigated with TLD rods in a body phantom containing tissue equivalent material. The CT examination consisted of scout view and both pre- and postcontrast scan series with 5 mm slice thickness and 5 mm unscanned intervals between successive scans. Cross-sectional dose distribution for one scan in the plane of the ovaries was measured as well as the dose profile for one scan along a line through the ovary parallel to the axis of rotation. Based on these measurements, the dose resulting from the whole CT examination was calculated, both with contiguous and noncontiguous scans. The ovarian dose was calculated for different positions of the ovaries in relation to the scanned area. The absorbed dose varied between 8.3 mGy and 9.7 mGy with the actual technique used. When contiguous scans with the same thickness were taken, the ovarian dose increased with a factor from 1.7 to 1.9. The dose resulting from the CT protocol of the urinary bladder was of the same magnitude as absorbed dose resulting from urography. When the diagnostic gain from a precise definition of tumor extent was taken into account, the dose resulting from the CT protocol was judged acceptable.

Computed tomography of invasive bladder carcinoma after diagnostic transurethral resection.

Fourteen patients with known muscle invasive bladder carcinoma were examined with computed tomography (CT) before and five to seven days after diagnostic transurethral resection (TUR). The CT examinations included pre- and postcontrast series. In order to standardize the technique, we examined on a distended bladder. No significant changes occurred for the whole group after TUR. Individual changes were seen. In six patients the largest measured area of the bladder tumor increased after resection and in four the largest measured thickness increased, and this should be borne in mind when CT is used to evaluate tumor response to treatment. Perivesical changes occurred only after extensive diathermy or perforation. They did not show contrast enhancement and could therefore not be mistaken for tumor growth.