Is the performance of MRI in preoperative staging of breast cancer independent of clinical and histological factors? A subgroup analysis.

OBJECTIVE: To determine whether preoperative breast MRI is more useful in patients according to their breast density, age, menopausal status, and biopsy findings of carcinoma in situ. MATERIAL AND METHODS: We retrospectively studied 264 patients treated for breast cancer who had undergone mammography, ultrasonography, and MRI. We compared the size of the tumor on the three techniques and the sensitivity of the techniques for detecting additional lesions both in the overall group and in subgroups of patients classified according to their breast density, age, menopausal status, and histological findings of intraductal carcinoma. The definitive histological diagnosis was used as the gold standard. RESULTS: MRI was the technique that was most concordant with the histological findings for the size of the lesion, and it was also the technique that detected the most additional lesions. With MRI, we observed no differences in lesion size between the overall group and the subgroups in which MRI provided added value. Likewise, we observed no differences in the number of additional lesions detected in the overall group except for multicentric lesions, which was larger in older patients (P=.02). In the subgroup of patients in which MRI provided added value, the sensitivity for bilateral lesions was higher in patients with fatty breasts (P=.04). Multifocal lesions were detected significantly better in premenopausal patients (P=.03). CONCLUSIONS: MRI is better than mammography and better than ultrasonography for establishing the size of the tumor and for detecting additional lesions. Our results did not identify any subgroups in which the technique was more useful.

[A review of the scientific evidence concerning the clinical application of digital mammography]. / Revisión de la evidencia científica sobre la aplicación clínica de la mamografía digital.

OBJECTIVE: To review the scientific evidence with respect to the use of digital mammography and compare it with analogical mammography in the clinical context. MATERIAL AND METHOD: We searched Medline and EMbase for studies published between 1989 and 2005 that compared the results of digital and analogical mammography in the same group of patients or in two different groups of patients to evaluate their respective diagnostic accuracy (sensitivity, specificity, area under the ROC curve), recall rate, biopsy rate, and exposure to radiation. We reviewed and compared the different methodologies of the studies published. RESULTS: Eight articles and eight presentations at congresses were found. No statistically significant differences were observed between digital and analogical mammography for the detection of breast cancer. Until the publication of the Oslo II (2004) and Digital Mammographic Imaging Screening Trial (2005) studies, the series presented were small and used a variety of methodologies. This made it impossible to appreciate small differences in diagnostic accuracy between the two techniques and to group the, sometimes, contradictory results. Furthermore, these first series did not include follow-up. CONCLUSION: There are no statistically significant differences between the two techniques for diagnostic accuracy, except in women with dense or heterogeneously dense breasts, in those under 50 years of age, and in peri- or pre-menopausal women, in which cases digital mammography is significantly better. These data should be confirmed in longer term studies to enable the effects on the breast cancer mortality rate to be specifically evaluated. Cost-effectiveness studies are important when considering changing techniques.

Helical CT of the stomach: differentiation between benign and malignant pathologies, together with the staging of gastric carcinoma.

OBJECTIVES: To evaluate the capacity of Helical Hydro-CT to differentiate between benign and malignant gastric pathologies, and also to measure its usefulness in the staging of gastric carcinoma. PATIENTS AND DESIGN: We perform a cross-sectional study to evaluate the diagnostic efficacy of CT, including patients prospectively. We study 92 patients with a clinical suspicion of gastric pathology using helical CT with a contrast agent (HCTC), water being the oral contrast agent, and i.v. iodine contrast. According to the findings of previous works, we considered stomachs to be normal when the thickness of their wall was less than or equal to 6 mm, with a multilayered appearance that stands out homogeneously with the i.v. contrast. A malignant tumour was diagnosed if the thickness of the wall was greater, together with strong marking by the contrast agent and loss of the normal multilayered pattern. Parietal thickening was classified as gastritis if there was no excessive marking and no loss of the layered pattern. Masses with smooth borders, intraluminal growth and a rounded morphology were diagnosed as sub-mucosal tumours. The results of our 92 studies were compared in all cases with the findings of endoscopic studies, while in the 52 patients treated with surgery they were compared against surgical findings. RESULTS: In 12 of the 92 patients studied using HCTC no gastric pathology was observed by CT or endoscopy. Of the 80 pathological cases CT was used to diagnose 29 as benign pathology, 19 of which were confirmed as such by histology, and 51 cases as malignant pathology, of which 49 were confirmed by histology. We obtained a sensitivity of 81.7% in the diagnosis of malignant pathology and a specificity of 90%, with a PPV of 96% and a NPV of 62%. Regarding TNM staging (in comparison with the 1997 TNM classification), the diagnostic reliability obtained amounted to 56% for T and N, and 87% for M. CONCLUSIONS: Helical hydro CT makes it possible to diagnose advanced gastric carcinoma. Its usefulness basically lies in the evaluation of metastatic neoplastic disease. It has also been shown to be useful in the diagnosis of benign pathologies. It is not a good screening method for the diagnosis of gastric carcinoma.