Comparison of in vitro breast cancer visibility in analyser-based computed tomography with histopathology, mammography, computed tomography and magnetic resonance imaging.

High-resolution analyser-based X-ray imaging computed tomography (HR ABI-CT) findings on in vitro human breast cancer are compared with histopathology, mammography, computed tomography (CT) and magnetic resonance imaging. The HR ABI-CT images provided significantly better low-contrast visibility compared with the standard radiological images. Fine cancer structures indistinguishable and superimposed in mammograms were seen, and could be matched with the histopathological results. The mean glandular dose was less than 1 mGy in mammography and 12-13 mGy in CT and ABI-CT. The excellent visibility of in vitro breast cancer suggests that HR ABI-CT may have a valuable role in the future as an adjunct or even alternative to current breast diagnostics, when radiation dose is further decreased, and compact synchrotron radiation sources become available.

Phase-contrast X-ray imaging of breast.

When an X-ray wave traverses an object, its amplitude and phase change, resulting in attenuation, interference, and refraction, and in phase-contrast X-ray imaging (PCI) these are converted to intensity changes. The relative change of the X-ray phase per unit path length is even orders of magnitude larger than that of the X-ray amplitude, so that the image contrast based on variation of the X-ray phase is potentially much stronger than the contrast based on X-ray amplitude (absorption contrast). An important medical application of PCI methods is soft-tissue imaging, where the absorption contrast is inherently weak. It is shown by in vitro examples that signs of malignant human breast tumor are enhanced in PCI images. Owing to the strong contrast, the radiation dose can be greatly reduced, so that a high-resolution phase-contrast X-ray tomography of the breast is possible with about 1 mGy mean glandular dose. Scattered radiation carries essential information on the atomic and molecular structure of the object, and particularly small-angle X-ray scattering can be used to trace cancer. The imaging methods developed at the synchrotron radiation facilities will become available in the clinical environment with the ongoing development of compact radiation sources, which produce intense X-ray beams of sufficient coherence. Several developments that are under way are described here.

Toward high-contrast breast CT at low radiation dose.

This study was approved by the local research ethics committee, and patient informed consent was obtained. The purpose of this study was to demonstrate that high-spatial-resolution low-dose analyzer-based x-ray computed tomography (CT) can substantially improve the radiographic contrast of breast tissue in vitro when compared with that attained by using diagnostic mammography and CT. An excised human breast tumor was examined by using analyzer-based x-ray imaging with synchrotron radiation. The correspondence between analyzer-based x-ray images and diagnostic mammograms, CT images, and histopathologic findings was determined. Calcifications and fine details of soft tissue, which are at the contrast detection limit on diagnostic mammograms, are clearly visible on planar analyzer-based x-ray images. Analyzer-based x-ray CT yields high contrast from smoothly varying internal structures, such as tumorous mass lesions, corresponding to information on actual structures seen at histopathologic analysis. The mean glandular dose of 1.9 mGy in analyzer-based x-ray CT is approximately equivalent to the dose administered during single-view screening mammography. The improved visibility of mammographically indistinguishable lesions in vitro suggests that analyzer-based x-ray CT may be a valuable method in radiographic evaluation of the breast, thereby justifying further investigations.

High-resolution CT by diffraction-enhanced x-ray imaging: mapping of breast tissue samples and comparison with their histo-pathology.

The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources.

Interferon alfa-2b three times daily and thalidomide in the treatment of metastatic renal cell carcinoma.

PURPOSE: The antiangiogenic effect of interferon (IFN) may improve with frequent dosing and by combination with other agents with antiangiogenic activity. To evaluate this potential, we treated patients with metastatic renal cell carcinoma (RCC) with frequently dosed IFN and thalidomide. PATIENTS AND METHODS: Thirty patients were given IFN-alpha-2b 0.9 MU subcutaneously three times daily for 1 month and subsequently 1.2 MU tid unless serious toxicity was encountered. Thalidomide was first given 100 mg/d for 1 week and 300 mg/d thereafter. Sera were collected before and during treatment for serum vascular endothelial growth factor (S-VEGF) analyses performed using enzyme-linked immunosorbent assay. RESULTS: The intention-to-treat response rate was 20% (95% CI, 6% to 34%) and response rate for assessable patients (n = 27) was 22% (95% CI, 6% to 38%). All responses were partial. In addition, 17 patients (63%; 95% CI, 45% to 81%) had stable disease for 3 months or longer. The median time to treatment failure was 7.7 months, and median survival time was 14.9 months. The most common cause of thalidomide discontinuation was neuropathy. S-VEGF levels decreased more in patients who responded to therapy compared with those in patients whose condition had stabilized or who had progressive disease (P =.036). CONCLUSION: The combination of frequently dosed IFN-alpha-2b and low-dose thalidomide is feasible and active in advanced RCC, but the clinical benefit may remain small compared with that of IFN alone. Results from an ongoing phase III trial comparing IFN-alpha with or without thalidomide need to be analyzed before this combination can be recommended for use outside clinical studies.

Visualisation of calcifications and thin collagen strands in human breast tumour specimens by the diffraction-enhanced imaging technique: a comparison with conventional mammography and histology.

Six excised human breast tissue specimens carrying benign and malignant tumours were examined with the diffraction-enhanced imaging technique. Diffraction-enhanced images were compared with diagnostic screen-film mammograms and the correlation with histological information of the specimens was established. The enhanced visibility of calcifications, some of which were smaller than 0.15 mm in diameter, is reported in detail. Fine details of the structures such as strands of collagen and contours between glandular and adipose tissue, which are barely visible at the contrast detection limit in the conventional absorption-based mammograms, are clearly visible in the diffraction-enhanced images. Microscopic study of the stained histopathological sections unequivocally confirms the correlation of the radiographic findings with the morphologic changes in specimens. An increased soft tissue contrast and a combination of information obtained with disparate diffraction-enhanced images provide better visibility of mammographically indistinguishable features. This kind of additional structural information of the breast tissue is required to improve assessment accuracy and earlier detection of the breast lesions. These advances in image quality make the method a very promising candidate for mammography.

Pulmonary toxicity after radiotherapy in primary breast cancer patients: results from a randomized chemotherapy study.

PURPOSE: Pulmonary toxicity was prospectively evaluated within a randomized trial for breast cancer patients at high risk for relapse, who postoperatively received as adjuvant therapy either 9 cycles of tailored chemotherapy (20 patients) (cyclophosphamide, epirubicin, 5-fluorouracil [FEC]) or standard FEC x 3 followed by high-dose chemotherapy (cyclophosphamide, thiotepa, carboplatin [CTCb]) supported by peripheral blood stem cell transplantation (14 patients). After high-dose chemotherapy or tailored FEC, all patients received locoregional radiotherapy (50 Gy/5 weeks), plus tamoxifen for 5 years. METHODS AND MATERIALS: Lung function tests (FVC, FEV1, and DL(CO)) were performed before chemotherapy and 9 months after radiotherapy. Computed tomography of the lungs was performed before radiotherapy and 6 weeks, 3 months, and 9 months after radiotherapy. RESULTS: Clinical signs of suspected pneumonitis were noted in 29% of patients, but only 1 patient needed symptomatic therapy. Radiologic changes were detected in 68% of patients, and they were most frequent at 3 months after radiotherapy. FVC decreased in both groups (tailored FEC: mean difference, -6.5%, p = 0.0005; CTCb: -2.0%, p = 0.21; tailored FEC vs. CTCb: -4.5%, p = 0.05). DL(CO) decreased significantly in both groups (tailored FEC: mean difference, -11.2%, p < 0.0001; CTCb: -5.6%, p = 0.02; tailored FEC vs. CTCb: -5.6%, p = 0.07). FEV1 decreased by 7.3% in patients treated with tailored FEC (p < 0.0001) and by 2.5% in patients treated with CTCb (p = 0.03) (tailored FEC vs. CTCb: 3.7%, p = 0.08). CONCLUSIONS: Changes in pulmonary function were thus detected in both groups, although to a greater extent in the tailored FEC group. The clinical significance of these findings should be balanced carefully against the improved, statistically significant relapse-free survival achieved with the tailored FEC regimen compared to high-dose CTCb + peripheral blood stem cell transplantation (PSCT).

Soft-tissue sarcomas of the upper extremity: surgical treatment and outcome.

The objective of this retrospective follow-up study was to evaluate the outcome of patients with soft-tissue sarcoma treated by the authors' protocol, which consists of a selective combination of conservative surgery and radiotherapy. Patients who relapsed were especially evaluated to improve treatment results. The authors examined 80 patients with local soft-tissue sarcoma in the upper extremity referred to their multidisciplinary group. Fifteen patients were referred for first or subsequent local recurrence, and 65 patients were treated for primary tumor. The goal of treatment was local control and preservation of a functional limb. Wide excision was attempted. If the margin was less than 2.5 cm, postoperative radiotherapy was administered. Eighty-five percent of the patients were treated by limb salvage. Thirty patients needed reconstructive procedures such as pedicled (20 patients) or free flaps (10 patients). No free flaps were lost. The 5-year disease-specific overall survival rate was 75 percent, the local recurrence-free survival rate was 79 percent, and the metastasis-free survival rate was 68 percent. In univariate analysis, prognostic factors for local recurrence were extracompartmental site; for development of metastases, large size and extracompartmental site; and for decreased disease-specific overall survival, large size and extracompartmental site. Intramuscular, cutaneous, and subcutaneous tumors had a 5-year local control rate of 100 percent, and extracompartmental tumors had a local control rate of 69 percent. Extracompartmental tumors clearly have the worst prognosis and should be the main target for improving treatment strategies. After exclusion of patients with inadequate treatment according to the authors' protocol, the local control rate at 5 years was 90 percent. Strict adherence to treatment protocol should be practiced.

Tissue-specific promoters active in CD44+CD24-/low breast cancer cells.

It has been proposed that human tumors contain stem cells that have a central role in tumor initiation and posttreatment relapse. Putative breast cancer stem cells may reside in the CD44(+)CD24(-/low) population. Oncolytic adenoviruses are attractive for killing of these cells because they enter through infection and are therefore not susceptible to active and passive mechanisms that render stem cells resistant to many drugs. Although adenoviruses have been quite safe in cancer trials, preclinical work suggests that toxicity may eventually be possible with more active agents. Therefore, restriction of virus replication to target tissues with tissues-specific promoters is appealing for improving safety and can be achieved without loss of efficacy. We extracted CD44(+)CD24(-/low) cells from pleural effusions of breast cancer patients and found that modification of adenovirus type 5 tropism with the serotype 3 knob increased gene delivery to CD44(+)CD24(-/low) cells. alpha-Lactalbumin, cyclo-oxygenase 2, telomerase, and multidrug resistance protein promoters were studied for activity in CD44(+)CD24(-/low) cells, and a panel of oncolytic viruses was subsequently constructed. Each virus featured 5/3 chimerism of the fiber and a promoter controlling expression of E1A, which was also deleted in the Rb binding domain for additional tumor selectivity. Cell killing assays identified Ad5/3-cox2L-d24 and Ad5/3-mdr-d24 as the most active agents, and these viruses were able to completely eradicate CD44(+)CD24(-/low) cells in vitro. In vivo, these viruses had significant antitumor activity in CD44(+)CD24(-/low)-derived tumors. These findings may have relevance for elimination of cancer stem cells in humans.

Oncolytic adenoviruses kill breast cancer initiating CD44+CD24-/low cells.

Cancer stem cells have been indicated in the initiation of tumors and are even found to be responsible for relapses after apparently curative therapies have been undertaken. In breast cancer, they may reside in the CD44(+)CD24(-/low) population. The use of oncolytic adenoviruses presents an attractive anti-tumor approach for eradication of these cells because their entry occurs through infection and they are, therefore, not susceptible to those mechanisms that commonly render stem cells resistant to many drugs. We isolated CD44(+)CD24(-/low) cells from patient pleural effusions and confirmed stem cell-like features including oct4 and sox2 expression and Hoechst 33342 exclusion. CD44(+)CD24(-/low) cells, including the Hoechst excluding subpopulation, could be effectively killed by oncolytic adenoviruses Ad5/3-Delta24 and Ad5.pk7-Delta24. In mice, CD44(+)CD24(-/low) cells formed orthotopic breast tumors but virus infection prevented tumor formation. Ad5/3-Delta24 and Ad5.pk7-Delta24 were effective against advanced orthotopic CD44(+)CD24(-/low)-derived tumors. In summary, Ad5/3-Delta24 and Ad5.pk7-Delta24 can kill CD44(+)CD24(-/low), and also committed breast cancer cells, making them promising agents for treatment of breast cancer.

Ultrasonography of the axilla in the follow-up of breast cancer patients who have a negative sentinel node biopsy and who avoid axillary clearance.

The clinical value of ultrasonography of the axilla in detection of breast cancer recurrence is not known among patients who have a negative sentinel node biopsy and avoid axillary clearance. We studied a cohort of 205 such patients using ultrasonography one and three years after breast surgery. A recurrent tumour was found in the axilla in only two (0.5%) of the total of 383 ultrasound examinations performed during the study, and only one (0.3%) of the 369 examinations performed at the scheduled study visits revealed cancer. None of the ultrasound examinations was false positive, and no study participant was subjected to unnecessary surgery due to ultrasound monitoring. We conclude that the rate of breast cancer recurrence in the ipsilateral axilla is low following sparing of the axillary contents, and that monitoring of such patients with repeated ultrasound examinations is unlikely to be cost-effective.

Ten-year follow-up of a randomized controlled trial of adjuvant clodronate treatment in node-positive breast cancer patients.

Ten-year follow-up results are presented of an adjuvant clodronate trial in patients with primary breast cancer. Between 1990 and 1993, 299 women with primary node positive breast cancer were randomized to oral clodronate 1600 mg daily (149) or controls (150) for 3 years. All patients received adjuvant chemo- or endocrine therapy. Within 10 years bone metastases were detected at the same frequency in the clodronate and control groups: 44 (32%) vs. 42 (29%), respectively, (p=0.35). The frequency of non-skeletal recurrences (visceral and local) was significantly higher in the clodronate group 69 (50%) as compared with the controls 51 (36%) (p=0.005). Ten-year disease-free survival (DFS) remained significantly lower in the clodronate group (45% vs. 58%, p=0.01, respectively). This was especially seen in oestrogen receptor negative patients (25% vs. 58%, p=0.004, respectively). No significant overall survival difference was found between the groups. As previously reported 3-year adjuvant clodronate treatment did not prevent the development of bone metastases in node-positive breast cancer patients. A negative effect of clodronate on DFS by increasing the development of visceral metastases was still seen at 10 years, but this did not significantly compromise overall survival.