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Differentiated papillary thyroid carcinoma (D-PTC) is the most common malignancy arising in the thyroid gland. There are gender differences in the incidence of PTC being mainly observed in females. Low-risk groups consisted of men younger than 40-year-old and women younger than 50-year-old, whereas the high-risk group are older patients. We believe that age is not enough to explain the clinical course of this neoplasm and hypothesize that aggressive behavior of D-PTC may be correlated with hormonal status. Studies that support this idea showed that the follicular neoplastic cells had higher estrogen receptor-alpha in premenopausal (28.1+/-4.5) than in postmenopausal women (14.2+/-2.9). According to author's prior observations, there are evidences correlating recurrence of D-PTC with postmenopause in women. Postmenopause status is characterized by estrogen decrease and FSH increases both associated with EGFR activation. Previous observations identified EGFR over-expression in D-PTC of postmenopause when compared with premenopausal ladies. Conclusions: Postmenopause is an adverse factor for tumor evolution in women with D-PTC and is associated with EGFR expression. It's introduction in thyroid tumor stratification could be a fine tuning in predicting papillary thyroid carcinoma behavior.  相似文献   
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The development and morphology of the rat mammary gland are dependent upon several hormones including estrogens, androgens, progesterone, growth hormone and prolactin. In toxicology studies, treatment with xenobiotics may alter these hormones resulting in changes in the morphology of reproductive tissues such as the mammary gland. In the rat, male and female mammary glands exhibit striking morphologic differences that can be altered secondary to hormonal perturbations. Recognizing these morphologic changes can help the pathologist predict potential xenobiotic-induced perturbations in the systemic hormonal milieu. This review examines the development of the rat mammary gland and the influence of sex hormones on the morphology of the adult male and female rat mammary gland. Specific case examples from the literature and data from our laboratory highlight the dynamic nature of the rat mammary gland in response to hormonal changes.  相似文献   
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BACKGROUND: Some patients with cryoglobulinemic syndrome (CS) develop frank non-Hodgkin lymphoma (NHL), but the incidence and timing of this event are still poorly defined. METHODS: A retrospective multicenter study was performed of hepatitis C virus-positive patients with CS observed in 11 Italian centers belonging to the Italian Group for the Study of Cryoglobulinemia. RESULTS: The inclusion criteria were satisfied by 1,255 patients. During a cumulative follow-up of 8,928 patient-years, 59 cases of NHL were diagnosed, for an estimated rate of 660.8 new cases per 100,000 patient-years with 224.1 new cases of aggressive NHL subtypes per 100,000 patient-years. More than 90% of the patients developing NHLs had type II cryoglobulins. The NHLs were classified as nonaggressive in 31 cases (53%), aggressive in 20 (34%), and mucosa-associated lymphoid tissue lymphomas in 6 (10%); 2 cases were unclassifiable. The median time from the diagnosis of CS to the clinical onset of NHL was 6.26 years (range, 0.81-24 years). The clinical course and response to chemotherapy in the patients with CS who had NHL were similar to those usually described in patients with NHL without CS; the course of the CS only marginally benefited from chemotherapy. CONCLUSIONS: The overall risk of NHL in patients with CS is about 35 times higher than in the general population (12 times higher if nonaggressive lymphomas are excluded). The presence of CS did not significantly affect the treatment of newly diagnosed lymphomas.  相似文献   
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