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1.
2.
《Cancer cell》2020,37(1):123-134.e5
3.
Maggie L. Westfal David C. Chang Cassandra M. Kelleher 《Journal of pediatric surgery》2019,54(1):140-144
Purpose
The purpose of this study was to evaluate trends in demographics and outcomes of pediatric breast cancer in a United States population-based cohort.Methods
The Surveillance, Epidemiology, and End Results (SEER) database was utilized to identify all pediatric patients with malignant breast tumors between 1973 and 2014. Analysis was performed using Stata Statistical Software version 13.1. Associations between categorical variables were made using X2 test. Log-rank test was used for univariate survival analysis. Kaplan–Meier analysis investigated five-year survival rates across several variables. Adjusted analysis was performed using a Cox Proportional-Hazards regression.Results
134 patients with breast malignancies were identified. Carcinoma was the most prevalent histology (48.5%), followed by fibroepithelial tumors (FETs) (35.1%), and sarcoma (14.2%). FETs were twice as common in black compared to nonblack patients (56.3% vs. 29.0%, p?<?0.01). Analyzing histology by stage revealed that 100% of FETs were early stage disease (p?<?0.0001). 46.7% of the tumors tested were ER/PR negative, more than twice as many compared to the published adult estimate of 20.0%. Unadjusted survival analysis revealed worse survival for patients with adenocarcinoma/sarcomas, advanced stage, and high grade disease, without a survival difference between races.Conclusion
Breast cancer remains a rare malignancy among pediatric patients. Although black patients were found to have more noncarcinomatous tumors with less advanced disease, this did not confer a survival advantage.Type of study
Retrospective cohort study.Level of evidence
Level III. 相似文献4.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
5.
Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear. 相似文献
6.
Herbert Radner Yosuf El-Shabrawi Robert H. Eibl Oliver Brüstle Lukas Kenner Paul Kleihues Otmar D. Wiestler 《Acta neuropathologica》1993,86(5):456-465
Introduction into fetal rat brain cells of a replication-defective retroviral vector harboring v-Ha-ras and v-gag-myc rapidly causes the induction of highly malignant undifferentiated neuroectodermal tumors following transplantation into the brains of syngeneic hosts [Wiestler, et al. (1992) Cancer Res. 52: 3760–3767]. In the present study, we have investigated the modulating effect of the developmental stage of neural target cells and of the dose of the retroviral vector used in the grafting experiments. Exposure of fetal cells from embryonic day (E)12 or E14 produced a 100% incidence of malignant neuroectodermal tumors which led to the death of recipient animals after a median latency period of 32 days. A 100-fold reduction of the virus dose from 2.062×106 to 2.062×104 focus-forming units/ml resulted in a lower tumor incidence of 25%. Of six neural grafts exposed to v-Ha-ras and v-myc at E16, only one showed evidence of tumorigenesis (low-grade astrocytoma and hemangioma). All other transplants were morphologically normal for observation periods of 26 weeks, indicating a marked loss of transforming activity of ras and myc in more advanced stages of brain development. In retrovirus-exposed donor cells which caused the development of neural tumors in recipient rats, malignant transformation was also evident during culture in vitro, usually after 9–12 days. Oncogene complementation was also studied in the newborn rat brain. After microinjection of the retroviral vector into the brain at postnatal day (P)0, P1 and P3, 5 out of 20 animals (25%) developed a total of seven brain tumors. Histopathologically, three of these neoplasms were malignant neuroectodermal tumors which, in contrast to those induced in fetal brain transplants showed evidence of focal glial and/or neuronal differentiation. In addition, we observed one oligodendroglioma, two hemangiomas and a malignant hemangioendothelioma. These data indicate that neural precursor cells and endothelia of the rat brain represent the major target cells for the complementary action of ras and myc and that the use of target cells from later developmental stages (E16 and postnatal) leads to the induction of both primitive and more differentiated neoplasms.These studies were supported by the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich (Erwin Schrödinger fellowship, JO501-MED), by the Swiss National Science Foundation and by the Cancer League of the Kanton of Zürich 相似文献
7.
Summary Intracavitary application of ultrasound was first performed for diagnostic purposes in 1967; since that time, it has been
more and more widely used. As far as the gastrointestinal tract is concerned, endoscopically controlled ultrasonic probes
provide visualization of the various layers of the intestinal wall. It is therefore possible to describe lesions of the esophagus,
stomach, and the rectum with regard to their nature and depth of infiltration. Furthermore, periesophageal and perigastric
organs can be visualized. It has become evident that endosonography is particularly important for pretherapeutic staging of
tumors of the esophagus, stomach, and rectum. Here prospective comparative studies confirm the superiority of this new diagnostic
procedure when compared to the methods available to date. 相似文献
8.
We report an 80-year-old Japanese male with four primary malignant tumors: malignant melanoma, prostatic cancer, malignant lymphoma, and renal cell carcinoma, which occurred in that respective order. The combination of malignant melanoma and malignant lymphoma is rare. The patient was treated with BCG after an operation for malignant melanoma. He was also treated with cobalt 60 irradiation after an operation for prostatic cancer. We also discuss other reports of multiple malignant tumors and suggest some possible causes of this patient's primary malignant tumors. 相似文献
9.
The reconstruction of a part of the body that has lost or inhibited function has been the most important aspect of reconstructive surgery in the past. Because of the existence of better techniques and the patient's wish for social reintegration, the plastic surgeon today is forced to consider the aesthetic results of his work more than in the past. Sometimes microsurgical procedures in reconstructive surgery are the only chance for the patient to be healed or palliated. Experience with more than 350 free tissue transfers gave us the opportunity to estimate the value of a donor flap with respect to the requirements of the receiving site. To satisfy the high aesthetic demands in these cases, it was necessary for the right place and shape the flap to fit as closely as possible, even if further corrections were necessary to achieve a satisfactory result. The transfer of latissimus dorsi and radial forearm flaps to the face and lower leg is discussed in cases of tumorus diseases and severe injuries of young and old patients.Presented to the IXth Congress of the International Society of Aesthetic Plastic Surgery, New York, October 13, 1987 相似文献
10.
目的:探讨靶重建放大扫描技术对肺孤立性结节病变的诊断价值。方法:对63例患者先行常规CT平扫,选定结节处为兴趣区,行薄层靶重建放大扫描,层厚、层距为2mm,FOV为160。结果:42例恶性病变中有37例表现为深分叶,占88.1%;21例良性病变中有15例表现为浅分叶,占71.4%。恶性结节中15例内部出现条状低密度支气管征;7例出现血管集中征;8例出现空泡征;病变内部出现液化坏死13例,其中恶性病变ll例。22例出现钙化,包括12例良性病变和10例恶性病变。2例错构瘤内均见小面积脂肪性低密度影。结论:靶重建放大扫描比普通CT扫描可提供更多的信息,对良恶性病变的鉴别诊断有一定价值。恶性病变大多数为深分叶,良性病变大多数为浅分叶或无分叶。 相似文献