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21.
Interactions between pregnancy and breast cancer are complex and paradoxical. Epidemiological data show that nulliparity and late full-term pregnancy increase breast cancer risk. By contrast, early full-term pregnancy and multiparity are thought to be the most effective means of decreasing lifetime breast cancer risk. Paradoxically, young women diagnosed with breast cancer during pregnancy have a higher risk of dying from their disease. Moreover, there is a transient increase in risk of breast cancer in the first three to four years after pregnancy. After breast cancer treatment, there is no evidence that pregnancy increases the risk of breast cancer recurrence. Thus, it is not contraindicated in women previously treated for breast cancer and free of recurrence. Various physio-pathological mechanisms are involved in the protective effect of pregnancy, like cellular differentiation of mammary cells, mammary gland involution, circulating anti-mucin antibody and excretion in the milk of breast carcinogens. In the past, unfavorable effects of pregnancy were mainly attributed to precancerous cell proliferation induced by pregnancy-associated hormonal changes. However, recent studies suggest that the remodeling of cellular microenvironment and extracellular matrix during pregnancy and involution may contribute to enhanced invasive and metastatic potential of breast carcinomas.  相似文献   
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Primary intracranial germ cell tumors are rare, often affecting children and young patients. Germinomas are the most common type of germ cell tumors. We present the case of a 10-year-old child, who was admitted with decreased visual acuity, asthenia, polyuro-polydipsic syndrome, and gait disorder. His biological assessment showed an hypocortisolemia and diabetes insipidus. Imaging found a bifocal process in the suprasellar and pineal region, suggestive of a bifocal germinoma. Imaging data and the positivity of human chorionic gonadotrophin in the cerebrospinal fluid were in favor of the diagnosis of bifocal germinal tumor confirmed by biopsy. Currently the patient is hospitalized in pediatric oncology department.The diagnosis of germ cell tumors is based on imaging, tumor marker assays, and biopsy. They are treated by radiation therapy alone or in combination with reduction chemotherapy, and surgery for tumor residues. The location of the tumor usually makes surgery difficult.  相似文献   
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Pheochromocytomas arising from outside the adrenal glands are called paragangliomas and constitute a rare disease and can occur in the pelvic retroperitoneum. Symptoms of excess catecholamine production, as well as elevated urine vanillylmandelic acid levels and serum and urine norepinephrine levels, are highly diagnostic for paraganglioma. Imaging can be helpful for the diagnostic of these pelvic tumors, differentiating them from other pelvic masses. We hereby present a case of pelvic malignant paraganglioma.  相似文献   
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We report a case of a patient who presented for ACTH‐dependent Cushing after a confirmed hypercortisolism and an inadequate normal ACTH. A transsphenoidal surgery of a pituitary picoadenoma has been done. After surgery, the patient showed the persistence of hypercortisolism. CT scan revealed adrenal adenomas removed surgically and improved the patient.  相似文献   
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The rapidly evolving technology of bone mineral density (BMD) testing has revolutionized the clinical care of osteoporosis; however, at present, there are no guidelines for BMD reporting. A survey was mailed to a random sample of bone densitometry centers in the United States registered in the National Osteoporosis Foundation database in order to evaluate the practice of BMD reporting in the United States. Of the 1200 questionnaires mailed, 22.5% were completed and returned. Spine and hip BMD were routinely measured at 71% of the centers and were expressed as T-scores by 90% of centers. The World Health Organization working group definition of osteoporosis was included in the report by 64% of the survey responders and was used as the sole criterion to make treatment recommendations by 34%. Fracture risk was reported by 70% of the centers and only the minority (<15%) applied appropriate age and gender restrictions. There were geographic and specialty variations in the practices of bone density reporting. Despite the established value of clinical densitometry in the care of patients at risk for osteoporosis, our survey revealed that clinical information, including fracture risk, was missing from many reports. A re-examination of the practice of clinical densitometry reporting is warranted.  相似文献   
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