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991.
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A case of a 78‐year‐old woman with a CD8‐positive peripheral T‐cell lymphoma with aberrant expression of CD20 associated with follicular lymphoma in situ (FLIS) is reported. The neoplasm presented initially as cutaneous macules, papules, plaques and nodules. A skin biopsy was performed and the diagnosis of peripheral T‐cell lymphoma (PTCl) with aberrant expression of CD20 was made. The staging procedures included an excisional inguinal lymph node biopsy that showed findings similar to those of the previous diagnosis. In addition, FLIS was identified. The clinicopathologic features of PTCLs with aberrant CD20 expression involving the skin as well as this uncommon association are reviewed.  相似文献   
993.
BACKGROUND AND PURPOSE: To analyze early results of a single institution experience using adjuvant intraoperative electron radiation therapy (IOERT) presacral boost in locally advanced rectal cancer following preoperative chemoradiation.Materials and methods: In a 63 month period (March 1995-June 2000), 100 consecutive T(3-4)N(x) rectal cancer patients were treated with preoperative chemoradiation (45-50 Gy plus oral Tegafur or 5-Fluorouracil continuous intravenous infusion), radical surgery and IOERT presacral boost (mean dose, 12.5 Gy; range, 10-15 Gy). Adjuvant chemotherapy (5-FU-leucovorin: 4-6 cycles) was given to 52 patients. The median age was 63 years, and 39 patients were >or=70 years old (65 males). Clinical staging was performed with computed tomography (94%) and/or endorectal ultrasound (71%) categorizing 90 cT(3), 10 cT(4), 20 cN(x), and 36 cN(+). Abdomino-perineal resection was performed in 41 cases. RESULTS: The IOERT cancellation rate was 6%. With a median follow-up of 23 months in IOERT treated patients, three developed pelvic recurrence: one anastomotic and one in the posterior vaginal wall (simultaneously with distant metastatic disease); and one presacral (in-field IOERT) as the only site of initial failure. Distant metastasis has been observed in 14 patients (exceptionally in pT(0-1) downstaged patients: 1/20; 5%). Overall treatment tolerances, including neoadjuvant and surgical segments, were acceptable. The actuarial 4-year estimations of local control, disease-free and overall survival are 94, 75 and 65%, respectively. CONCLUSIONS: IOERT electron boost to the presacral region is feasible to integrate systematically in the intensive combined treatment of locally advanced rectal cancer, including neoadjuvant chemoradiation segment. Topography of pelvic recurrences identified 2/3 relapses located in non-IOERT boosted anatomic intrapelvic sites: posterior vaginal wall and anastomotic suture. Presacral recurrence in locally advanced rectal cancer seems to be of low incidence, in a non-subspecialized academic surgical practice coordinated with a multidisciplinary oncology evaluation context, if an IOERT boost is included as a component of treatment together with preoperative chemoradiation.  相似文献   
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Diagnosis and treatment of renal cell carcinoma with venous tumor thrombosis remains a challenge today, requiring multidisciplinary teams, mainly in tumor thrombus levels III-IV. Our objective is to present the various diagnostic techniques used and its controversies. A review of the most relevant related articles between January 2000 and August 2020 has been carried out in PubMed, EMBASE and Scielo. Continuous technological development has allowed progress in its detection, in the approximation of the histological subtype, and in the determination of tumor thrombus level. Regardless of the imaging technique used for its diagnosis (CT, MRI, TEE, ultrasound with contrast), the time elapsed until treatment is vitally important to reduce the risk of complications, some of them fatal, such as pulmonary thromboembolism.  相似文献   
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To examine potential mechanisms by which hematopoiesis may be regulated by endothelial cells within the bone marrow (BM) microenvironment, we have devised a technique for the in vitro study of the interaction of human BM microvascular endothelial cells (BMEC) with hematopoietic cells. Microvessels isolated by collagenase digestion of spicules obtained from filtered BM aspirate were plated on gelatin-coated plastic dishes, and colonies of endothelial cells grown from microvessel explants were further purified by Ulex europaeus lectin affinity separation. BMEC monolayers isolated by this technique grew in typical cobblestone fashion, stained positively with antibody to factor VIII/von Willebrand factor, and incorporated acetylated LDL. Immunohistochemical studies showed that BM microvessels and BMEC monolayers express CD34, PECAM, and thrombospondin. Incubation of resting BMEC with BM mononuclear hematopoietic cells resulted in the selective adhesion of relatively large numbers of CD34+ progenitor cells and megakaryocytes. The binding of purified BM-derived CD34+ progenitor cells to BMEC was dependent on divalent cations and was partially blocked by antibodies to CD34. IL-1 beta treatment of BMEC monolayers resulted in an increase of CD34+ progenitor cell adhesion by mechanisms independent of CD34 or divalent cations. BMEC exhibit specific affinity for CD34+ progenitor cells and megakaryocytes, suggesting that the BM microvasculature may play a role in regulating the trafficking, proliferation, and differentiation of lineage specific hematopoietic elements, and possibly of pluripotent stem cells within the CD34+ population.  相似文献   
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