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941.
The association of pleuropulmonary blastoma and cystic nephroma is an uncommon entity, with only 4 cases of such an association in the same patient described in English literature. We report a 5th histologically documented case in a 32-month-old boy. The boy underwent a pulmonary biopsy that showed a pleuropulmonary blastoma and a nephrectomy that showed a cystic nephroma. The pleuropulmonary mass showed an important regression with postbiopsy chemotherapy, allowing subsequent tumorectomy. To date very little is known about this rare entity, and a genetic link between these 2 tumors is hypothesized.  相似文献   
942.
Referrals to genetics services are becoming increasingly common for patients who are diagnosed with early-onset colorectal cancer (CRC) or patients who have a family history of CRC. Microsatellite instability (MSI) testing and immunohistochemical analysis (IHC) of the patient’s tumor tissue, which assess indirectly the cellular status of DNA mismatch repair, have proven important tools for geneticists and genetic counselors to determine whether or not these individuals may be at risk for an inherited cancer syndrome, Lynch syndrome (a subset of hereditary nonpolyposis colorectal cancer). The application of tumor MSI/ IHC also extends to the group of providers involved in the diagnosis and management of CRC, demonstrating the growing clinical applicability of MSI/IHC testing. This review discusses the clinical utility of MSI/IHC analysis, including its benefits and limitations, and addresses some of the current debates surrounding testing.  相似文献   
943.
The vast majority of new cases of colorectal cancer, the second most common cause of death in men and women in the United States, are attributable to environmental rather than genetic causes. Recent research has clarified inconsistencies in the literature and has explored new pathways through which risk factors may act. This review discusses newly published, selected interesting and important findings in colorectal cancer etiology; these include postmenopausal hormone use, nonsteroidal anti-inflammatory drug use, obesity, physical activity, diet, and other confirmed epidemiologic associations. This research provides insight into mechanisms and offers opportunities for prevention.  相似文献   
944.
PURPOSE: To investigate variations of circulating serum levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and interleukin-10 (IL-10) during three-dimensional conformal radiation therapy (3D-CRT) in patients with non-small-cell lung cancer and correlate these variations with the occurrence of radiation pneumonitis. PATIENTS AND METHODS: Ninety-six patients receiving 3D-CRT for stage I to III disease were evaluated prospectively. Circulating cytokine levels were determined before, every 2 weeks during, and at the end of treatment. Radiation pneumonitis was evaluated prospectively between 6 and 8 weeks after 3D-CRT. The predictive value of clinical, dosimetric, and biologic (cytokine levels) factors was evaluated both in univariate and multivariate analyses. RESULTS: Forty patients (44%) experienced score 1 or more radiation pneumonitis. No association was found between baseline cytokine levels and the risk of radiation pneumonitis. In the whole population, mean levels of TNFalpha, IL-6, and IL-10 remained stable during radiotherapy. IL-6 levels were significantly higher (P = .047) during 3D-CRT in patients with radiation pneumonitis. In the multivariate analysis, covariations of IL-6 and IL-10 levels during the first 2 weeks of 3D-CRT were evidenced as independently predictive of radiation pneumonitis in this series (P = .011). CONCLUSION: Early variations of circulating IL-6 and IL-10 levels during 3D-CRT are significantly associated with the risk of radiation pneumonitis. Variations of circulating IL-6 and IL-10 levels during 3D-CRT may serve as independent predictive factors for this complication.  相似文献   
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