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61.
Colorectal adenocarcinoma with micropapillary pattern and its association with lymph node metastasis. 总被引:1,自引:0,他引:1
Micropapillary carcinoma has been reported as an aggressive variant of carcinoma in several organs, where it is associated with frequent lymphovascular invasion and poor clinical outcome. This study explored the clinicopathological features of colorectal adenocarcinoma with a micropapillary carcinoma component and compared them with those of conventional colorectal adenocarcinoma. One hundred seventy-eight consecutive cases of surgically resected colorectal carcinomas were studied for tumor size, type, depth of invasion, nodal and distant metastases, tumor stage, and percentage and extent of micropapillary component. Among 178 cases of colorectal carcinoma, 34 (19.1%) cases had a micropapillary component, which ranged from 5 to 60% of the entire tumor. Lymph node metastasis was identified in 25 of 34 (73.5%) carcinomas with micropapillary component, whereas they were detected in 61 of 144 (42.4%) cases without micropapillary component (P=0.001). Lymphovascular invasion was identified more frequently in carcinoma with micropapillary component (41.2%) than carcinoma without micropapillary component (20.1%; P<0.05). Distant metastases occurred in 4 of 34 cases (11.7%) with micropapillary component and in 10 of 144 cases (6.9%) without micropapillary component (P=0.311). Multivariate regression analysis demonstrated that the presence of micropapillary component, as well as tumor stage and lymphovascular invasion are independent predictors of regional nodal metastasis. 相似文献
62.
63.
Lee KW Yun T Song EK Na II Shin H Bang SM Lee JH Lee ST Kim JH Yoon SS Lee JS Park S Kim BK Kim NK 《Journal of Korean medical science》2005,20(4):598-562
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely. 相似文献
64.
We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature. 相似文献
65.
Alterations in the INK4a/ARF locus and their effects on the growth of human osteosarcoma cell lines 总被引:4,自引:0,他引:4
Park YB Park MJ Kimura K Shimizu K Lee SH Yokota J 《Cancer Genetics and Cytogenetics》2002,133(2):105-111
Two different proteins, p16(INK4a) and p14(ARF), encoded by the INK4a/ARF locus play important roles in the RB and p53 pathways, respectively. This study was performed to determine genetic and epigenetic alterations in the INK4a/ARF locus and their effects on the growth of osteosarcoma. Among six cell lines examined, both p16(INK4a) and p14(ARF) exons were homozygously deleted in two cell lines, MG63 and HOS, and both p16(INK4a) and p14(ARF) promoters were methylated in one cell line, U2OS. Wild-type mRNA and proteins for p16(INK4a) and p14(ARF) were expressed in three other cell lines, SaOS2, HuO9, and G292. Transfection studies were performed using two cell lines, U2OS and MG63. Both the RB and p53 genes were wild types in U2OS, whereas p53 but not RB was mutated in MG63. Both p16(INK4a) and p14(ARF) suppressed the growth of U2OS, whereas p16(INK4a) but not p14(ARF) suppressed the growth of MG63. p53 only did not suppress the growth of MG63 either; however, coexpression of p14(ARF) with p53 increased the fraction of the G0/G1 phase in MG63 cells. The data presented here demonstrate the importance of genetic and epigenetic alterations in the INK4a/ARF locus for the growth of osteosarcoma and thus will be useful to further understand the biologic behavior of osteosarcoma in association with the defects in the p53 and RB pathways. 相似文献
66.
DNA repair gene XRCC1 Arg399Gln polymorphism is associated with increased risk of uterine leiomyoma 总被引:2,自引:0,他引:2
Jeon YT Kim JW Park NH Song YS Kang SB Lee HP 《Human reproduction (Oxford, England)》2005,20(6):1586-1589
BACKGROUND: DNA repair gene XRCC1 Arg399Gln polymorphism has been associated with the risk of several human tumours. In the present study we investigated whether the XRCC1 polymorphism is related to the risk of uterine leiomyoma, the most common neoplasm of the female genital tract. METHODS: Three hundred and twenty-seven patients with uterine leiomyoma and 197 normal controls were enrolled, and XRCC1 genotyping was determined by PCR and restriction fragment length polymorphism. RESULTS: The proportions of individuals homozygous for 399Arg allele, heterozygous and homozygous for the 399Gln allele were 85.8%, 13.7% and 0.5% among the control group, and 46.2%, 53.2% and 0.6% in those with leiomyoma (P < 0.001), respectively. Logistic regression analysis (after adjusting for age, parity, menarche age and body mass index) showed a significant increased risk of uterine leiomyoma in women with the Arg/Gln genotype versus the Arg/Arg genotype (odds ratio 6.79; 95% confidence interval 4.20-10.99; P < 0.001). CONCLUSIONS: In Korean women, the 399Gln polymorphism of XRCC1 is associated with an increased risk of uterine leiomyoma. 相似文献
67.
A number of investigators have performed in vitro measurements of cancellous bone to determine how various ultrasonic parameters depend on bone density and trabecular orientation. To facilitate handling and storage of bone specimens, the marrow is often removed prior to ultrasonic measurements. However, the assumption that marrow does not affect ultrasonic measurements at high frequencies (>1 MHz) has not been tested. The goal of this study is to determine the effect of marrow on the ultrasonic properties of bovine cancellous bone at frequencies greater than 1 MHz. Twelve specimens of cancellous bone were obtained from the proximal end of four bovine tibia. Ultrasonic measurements consisting of normalized broadband ultrasonic attenuation (nBUA), speed of sound (SOS) and apparent integrated backscatter (AIB) were measured in each specimen using 2.25 MHz (centre frequency) broadband ultrasonic pulses. These measurements were performed before and after marrow removal either along the superoinferior (SI) or mediolateral (ML) direction. SOS and nBUA showed no significant difference (p > 0.05) for either direction of propagation after marrow removal. AIB showed no significant difference in the SI direction. For the ML direction, a small but statistically significant difference (p = 0.044) was observed after marrow removal. 相似文献
68.
Hyperreactio luteinalis is characterized by moderate to marked cystic enlargement of the ovaries related to multiple theca lutein cysts and is associated with very high sex steroid concentrations. It is a rare condition especially in the first trimester. The case described below is believed to be the only case of hyperreactio luteinalis reported following frozen embryo transfer. This case provides an opportunity to gain further insight into the mechanism responsible for this unusual condition. The 30 year old woman demonstrated a slightly elevated LH/FSH ratio (5 and 3 mIU/ml respectively) and normal baseline androgen concentrations. Two years following oocyte retrieval she had a second frozen embryo transfer. The ovaries were normal size when the embryos were transferred and androgens were still normal. The ovaries did not begin to enlarge until 51 days from transfer. A dichorionic intrauterine pregnancy with monozygotic twins in the left gestational sac was seen. Eventually, 86 days from transfer, the ovaries enlarged to 145x103x116 mm right; and 83x95x117 mm left. Serum oestradiol was 30 078 pg/ml, beta-human chorionic gonadotrophin (HCG) 239 920 mIU/ml, serum progesterone >160 ng/ml, total testosterone 2254 ng/dl, free testosterone 42.3 pg/ml and androstenedione 7328 ng/dl. Throughout the first trimester, serum FSH was <1 mIU/ml. Thus, neither FSH nor a corpus luteum is necessary to initiate this syndrome. 相似文献
69.
70.
An unusual localization of localized colitis cystica profunda in a 31-year-old man is described. The patient presented as anal bleeding and a protruding mass at the descending colon; the mass was polypoid and was made up of papillary epithelial hyperplasia with downward herniation of glands into the submucosa. Only one similar case involving a descending colon has been reported in the world literature. 相似文献