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71.
The patient was a 70‐year‐old woman with lymphoplasmacytic lymphoma which showed a predominantly diffuse involvement of the bone marrow and kidney. Because atypical lymphocytes appeared in the cerebrospinal fluid, the intrathecal administration of methotrexate (MTX) and cytosine arabinoside (Ara‐C) was repeated several times. The patient developed flaccid paraplegia 8 months after the beginning of intrathecal administration, and died 4 months later. Autopsy demonstrated extensive transverse necrosis involving the lower thoracic cord and marked vacuolar degeneration of the white matter of the cervical, upper thoracic and lumbo‐sacral cord. Focal vacuolar degeneration of the white matter was also noted in the left parietal lobe. Although vacuolar degeneration of the white matter is a common feature in MTX myelopathy, extensive transverse necrosis is rare. In the present case, an overlapping of two mechanisms, that is, injury of vascular endothelial cells and the direct toxic effect of MTX and Ara‐C on the white matter, probably played a crucial role in the pathogenesis of severe myelopathy. Because severe myelopathy occurs infrequently, considering the large number of patients receiving the intrathecal administration of MTX, it is possible that a constitutional predisposition or abnormal sensitivity to MTX was involved in the pathogenesis in the present patient.  相似文献   
72.
Gliomatosis cerebri is a rare diffuse glioma that is neither mass‐forming nor necrotic, and does not disrupt existing structures. Gliomatosis occurring in the cerebellum is known as gliomatosis cerebelli, and only three such cases examined by biopsy have been reported. Here we describe the first autopsy findings of a patient who was diagnosed as having gliomatosis in the cerebellum. Neuropathological examination identified the tumor cells as being positive for glial fibrillary acidic protein, vimentin and nestin, with atypical nuclei that were cashew‐nut‐ or dishcloth‐gourd‐shaped. These tumor cells were dense in the right cerebellum, but also spread broadly throughout the brain including the left cerebrum and optic nerve. Mitotic figures were frequently seen in the cerebellum, brain stem and cerebrum. Scherer's secondary structures were evident not only in the cerebellum but also the cerebrum. No necrosis, microvascular proliferation or destruction of anatomical structures was detected in the whole brain. Differences in the origin of the tumors of the gliomatoses cerbri and cerebelli suggests these tumors are different types of brain tumors. Thus the findings support that the gliomatosis cerebelli is a novel type of brain tumor classification. Furthermore, by the similarities of the histological features among the tumors, it appears appropriate to establish a novel category of “gliomatosis encephali” which includes both gliomatosis cerebri and gliomatosis cerebelli.  相似文献   
73.

Background

The importance of Notch signaling in colorectal cancer (CRC) tumorigenesis has been recently recognized. However, the significance of Notch3 expression and its association with Notch1 expression in CRC is unclear. In the present study, we investigated Notch1 and Notch3 expression in Stage II and III CRC to assess their association with clinicopathological characteristics.

Methods

The protein expression of Notch1 and Notch3 was examined using immunohistochemistry in 305 CRC specimens. Nuclear expression of Notch1 and Notch3 and their associations with clinicopathological characteristics and distant relapse-free survival (dRFS) were evaluated.

Results

Nuclear Notch1 was overexpressed in 37 % of specimen, and nuclear Notch3 in 38 %. Nuclear Notch3 expression correlated with tumor differentiation status (P = 0.0099). Nuclear expression of Notch1 and Notch3 was associated with tumor recurrence (P = 0.0311 and P = 0.0053, respectively). In multivariate analysis, nuclear Notch3 expression [hazard ratio (HR) = 1.71; 95 % confidence interval (CI), 1.06–2.78; P = 0.0271), lymph node metastasis, and venous involvement were independently correlated with dRFS. In subgroup analysis, nuclear Notch3 expression was strongly associated with dRFS in Stage II CRC (HR = 3.47; 95 % CI 1.44–9.22; P = 0.0055). Both nuclear Notch1 and Notch3 were positive in 67 specimens (22 %) and both were negative in 144 specimens (47 %). Coexpression of nuclear Notch1 and Notch3 had an additive effect toward poorer dRFS compared with a negative subtype (HR = 2.48; 95 % CI, 1.41–4.40; P = 0.0019).

Conclusions

Nuclear Notch3 expression might be a novel predictive marker for recurrence in Stage II and III CRC.  相似文献   
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75.
Atypical hemolytic uremic syndrome (aHUS) is rare and comprises the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Recently, abnormalities in the mechanisms underlying complement regulation have been focused upon as causes of aHUS. The prognosis for patients who present with aHUS is very poor, with the first aHUS attack being associated with a mortality rate of ~25 %, and with ~50 % of cases resulting in end-stage renal disease requiring dialysis. If treatment is delayed, there is a high risk of this syndrome progressing to renal failure. Therefore, we have developed diagnostic criteria for aHUS to enable its early diagnosis and to facilitate the timely initiation of appropriate treatment. We hope these diagnostic criteria will be disseminated to as many clinicians as possible and that they will be used widely.  相似文献   
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79.
We report a rare case of disseminated carcinomatosis of the bone marrow from rectal cancer with disseminated intravascular coagulation (DIC). A 65-year-old man was admitted with melena and low back pain at rest. X-ray examination showed rectal cancer with multiple bone metastases. Laboratory examination showed severe anemia and DIC. Histologic examination showed disseminated carcinomatosis of the bone marrow. The DIC was considered to be caused by disseminated carcinomatosis of the bone marrow from rectal cancer, and we immediately started treatment with anti-DIC therapy and anticancer chemotherapy with the modified FOLFOX6 regimen (mFOLFOX6). After some response to therapy, the patient''s general condition deteriorated, and he died 128 days after admission. This is the first English report showing disseminated carcinomatosis of the bone marrow from colorectal cancer treated with mFOLFOX6.Key words: Bone marrow neoplasms, Rectal neoplasms, Disseminated intravascular coagulationBone metastases diffusely invading the bone marrow with disseminated intravascular coagulation (DIC) and microangiopathic hemolytic anemia (MHA) tend to accompany solid tumors; this condition is called disseminated carcinomatosis of the bone marrow,1 and it is associated with an extremely poor prognosis. Among solid tumors, DIC is most commonly associated with breast cancer, prostate cancer, and lung cancer2,3; carcinomatosis arising from colorectal cancer is rare.Herein we report on a patient with disseminated carcinomatosis of the bone marrow with rectal cancer who developed acute DIC and was treated with a modified FOLFOX6 regimen (mFOLFOX6). We also review 11 similar previously reported cases.410  相似文献   
80.
The aim of the present study was to explore the unfavorable subset of patients with Stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). Recurrence-free survival rates were examined in 52 patients with stage T1N2-3M0 and stage T3N0M0 gastric cancer between January 2000 and March 2010. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. The recurrence-free survival (RFS) rates of the patients with stages T1N2, T1N3, and T3N0 cancer were 80.0, 76.4, and 100% at 5 years, respectively. The only significant prognostic factor for the survival rates of the patients with stage pT1N2-3 cancer measured by univariate and multivariate analyses was pathological tumor diameter. The 5-year RFS rates of the patients with stage pT1N2-3 cancer were 60.0%, when the tumor diameters measured <30 mm, and 88.9% when the tumor diameters measured >30 mm (P = 0.0248). These data may suggest that pathological tumor diameter is associated with poor survival in patients with small T1N2-3 tumors. Because our study was a retrospective single-center study with a small sample size, a prospective multicenter study is necessary to confirm whether small tumors are risk factor for the RFS in T1N2-3 disease.Key words: Gastric cancer, Stage II, Adjuvant chemotherapyEvery year, more than 934,000 people develop gastric cancer worldwide. After lung cancer, gastric cancer is the second most frequent cancer-related cause of death.1 Complete resection is essential to cure gastric cancer. Patients with stage II or stage III gastric cancer often develop tumor recurrence, even after complete curative resections.In 2007, the Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer (ACTS-GC) phase III trial demonstrated that S-1 is effective as adjuvant chemotherapy in Japanese patients who have undergone curative D2 gastrectomy for advanced gastric cancer.2 In general, patients eligible for ACTS-GC were those diagnosed with pathological stages II and III. However, patients classified with pathological (p) stages T1N2M0, T1N3M0, and T3N0M0—which are classified as part of stage II—were excluded from the ACTS-GC trial. Because in the prior phase III studies comparing surgery alone and adjuvant chemotherapy, patients with stages T1N+ and T2-3/N0 cancer had excellent prognoses with 5-year overall survival (OS) rates of more than 80% from surgery alone,3,4 these patients were excluded from receiving adjuvant chemotherapy. Japanese Gastric Cancer Association (JGCA) guidelines clearly state that the standard treatment for these patients is surgery alone.5Therefore, patients with stage II gastric cancer have been divided into two groups: one for whom the standard treatment is surgery alone, and the other for whom the standard treatment is surgery and adjuvant chemotherapy with S-1. Before the advent of ACTS-GC, survival rates were poorer in the latter group than in the former. However, treatment with adjuvant chemotherapy with S-1 has reversed this trend. Now, patients in the latter group receiving S-1 adjuvant chemotherapy have 5-year OS rates of 84.2%.6 Therefore, it may be old rationale that dictates that patients in the former group should be excluded from receiving adjuvant chemotherapy, because the 5-year OS rates are now more than 80% by S-1 adjuvant chemotherapy in the latter group. Five-year OS rates of 80% would not be obtained by surgery alone. Among those patients with stage II gastric cancer assigned to the surgery alone group, some may have a poor prognosis and be good candidates for adjuvant chemotherapy. The aim of the present study was to explore the unfavorable subset of patients among those with stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0).  相似文献   
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