Fetal risk in diagnostic radiology.

It is not uncommon to encounter situations in which radiologic examinations are necessary for accurate diagnosis and effective treatment of an expectant mother. The potential deleterious health consequences to the developing embryo and fetus from in utero irradiation include fetal death, congenital malformations, growth retardation, and carcinogenic and mutagenic effects. The likelihood of each effect is greatly dependent on the radiation dose and the gestational age of the conceptus at the time of exposure. In general, the average fetal doses from diagnostic imaging are <50 mGy (5 rad) and have not been associated with any significant adverse fetal effects. However, each case should be evaluated on an individual basis, and the risks should be explained to the patient before the examination. In addition, every effort should be made to reduce the fetal dose to as low as reasonably achievable. The biological effects of in utero radiation exposure, estimated fetal doses from various radiologic examinations, and general guidelines regarding diagnostic imaging during pregnancy will be discussed in this article.

Breast cancer close to the nipple: does this increase the risk of nodal metastasis at diagnosis?

BACKGROUND: Previous studies of patients with invasive breast cancer examined, with mixed results, tumour location as a predictor of axillary lymph node metastasis. This study assessed whether tumour location in relation to the nipple impacts the presence of axillary lymph node metastasis at the time of diagnosis. METHODS: A retrospective review was undertaken of the medical records and available imaging of 285 patients diagnosed with invasive breast cancer between January 2001 to June 2007 at Boston University Medical Center. The incidence of axillary lymph node metastasis was correlated with tumour location in relation to the posterior nipple line to control for variation in breast size. Bivariate analysis identified significant variables that were applied to a multiple logistic regression model. RESULTS: Axillary lymph node metastasis was not significantly associated with tumour proximity to the nipple. In the multivariate logistic regression analysis, known prognostic factors for axillary metastasis, such as surgical size, lymphovascular invasion, and age of diagnosis, were significant, whereas breast density, palpability, and histologic grade were no longer significant. CONCLUSIONS: Our study found that there was no evidence that correlates intramammary tumour proximity to the nipple with the presence of axillary lymph node metastasis at diagnosis. However, known prognostic factors, such as lymphovascular invasion, surgical size, and younger age at diagnosis, are strong independent predictors for axillary lymph node involvement.