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101.
Local recurrence at a gastrojejunal anastomosis is common in patients after gastrectomy for gastric carcinoma, but recurrence at a jejunojejunal anastomosis without recurrence at a gastrojejunal anastomosis is extremely rare. We report a case of suture-line recurrence at a jejunojejunal anastomosis without recurrence at the gastrojejunal anastomosis or in the remnant stomach in a patient 23 months after receiving a Billroth II gastrectomy for gastric cancer. We attributed the implantation of cancer cells at the jejunojejunal anastomosis to contamination of the stapler with cancer cells exfoliated in the gastric mucus during the construction of the gastrojejunal anastomosis. We therefore consider that different surgical instruments, such as automatic anastomotic devices and automatic suturing devices, must be used in each phase of the surgical procedure for gastric cancer.  相似文献   
102.

Introduction

Expression of the DLL4 (a notch pathway ligand) by tumor-associated endothelium is a postulated marker of vascular maturity and functionality. As vascular functionality is an important parameter defining chemotherapy and oxygen intra-tumoral distribution, we investigated the role of DLL4 expression in tumour vasculature in the efficacy of radio-chemotherapy for HNSCC patients.

Materials and methods

Sixty-five biopsy specimens from HNSCC patients with inoperable disease were immunohistochemically examined using anti-CD31 (pan-endothelial cell marker) and anti-DLL4 antibodies and the vascular density (VD) was recorded. Patients were treated with platinum based hypofractionated accelerated conformal radiotherapy. The median follow-up period was 24 months (4–80 months).

Results

Using the 33rd and 66th percentiles cases were grouped in three categories of low, medium and high CD31+ or DLL4+ VD. The percentage of vessels expressing DLL4 (DLL4-ratio) ranged from 17 to 100 % (mean 71 %), showing substantial variation among cases. In accordance with previous published studies, a biphasic pattern of association of CD31+ VD with poor outcome was noted. Cases with a medium VD had a significantly better local relapse free survival (LRFS) compared to cases of high VD (p = 0.0005, HR 0.15) and of low VD (p = 0.02, HR 0.28). High DLL4/CD31 ratio defined improved LRFS in both these subgroups of poor prognosis.

Conclusions

The expression of DLL4 is associated with reduced radio-resistance, presumably by reducing hypoxia and improving chemotherapy accessibility. Using the combination of CD31 and DLL4 staining, a classification is suggested so that HNSCCs are categorized in sub-groups to be targeted by different anti-angiogenic and hypoxia targeting agents.  相似文献   
103.
104.
Breast carcinomas have been reported to contain a subpopulation of CD44+/CD24− tumor cells with stem cell–like properties. This study investigates the significance of these two molecules in connection with tumor aggression and prognosis. The phenotypic profile of 139 breast carcinomas was investigated in paraffin sections using markers previously associated with stem cell–like properties (CD44, CD24), the “triple-state” (ER, PR, c-erb-B2), and angiogenesis (CD31). Tumors with >10% of CD44 and CD24 cancer cells were considered positive. The prevalence of CD44+ and CD24+ breast carcinomas in the series was 51.8% and 41.7%, respectively. Patients with the CD44(+)/CD24(−) phenotype had a 10-year lower median age at presentation and harbored tumors with a triple-negative state. They experienced an unfavorable prognosis. Lack of CD44 expression was associated with lymph node involvement, regardless of CD24 status, whereas the lack of both CD44 and CD24 was connected with high histologic grade and unfavorable prognosis which, notably, was the worse among all phenotypes. In multivariate analysis, the CD44(−)/CD24(−) phenotype, the nodal involvement, the vascular density and the ER-/PR-/c-erbB-2-profile were independent prognostic variables. It is concluded that assessment of the CD44/CD24 status may reveal distinct subgroups of breast cancer patients with different clinical behavior. The unsatisfactory response of the triple-negative tumors to current chemotherapy and their intimate link with the CD44(+)/CD24(−) phenotype, makes CD44 targeting an attractive therapeutic alternative for breast cancer patients. The strong association between the CD44(−)/CD24(−) phenotype and prognosis requires further investigation.  相似文献   
105.
A 51-year-old female patient presented with iron deficiency anemia. Upper and lower gastrointestinal endoscopy were unremarkable. Computed tomography enteroclysis showed an ovoid 3×4-cm jejunal tumor with intraluminal protrusion and exophytic growth pattern, without lymphadenopathy or metastatic disease. Laparoscopic resection of the tumor was successfully carried out. Histologically, a mesenchymal tumor composed of spindle cells with an interlacing bundle pattern and high-mitotic activity greater than 10 mitoses/50 high-power fields were observed. The immunohistochemistry showed that the tumor was KIT (CD117)-, vimentin-, smooth muscle actin-, and S-100-positive, whereas it was CD34-negative. These findings were consistent with the features of a gastrointestinal stromal tumor. The patient had an uneventful postoperative course, and after 10 months of follow-up, she is well without any evidence of tumor recurrence.  相似文献   
106.
Autophagy is an intracellular pathway for the degradation of long-lived proteins and damaged organelles. It is, in essence, a recycling process allowing cells to survive oxygen and nutrient depletion. The expression of two autophagy-related proteins, beclin 1 and light chain 3A (LC3A) was investigated in 79 nodular cutaneous melanomas. The results were correlated with histopathological factors, vascular density, and hypoxia-related proteins [hypoxia-inducible factors (HIF1α and HIF2α) and lactate dehydrogenase 5]. The reactivity of both autophagy-related proteins was uniformly cytoplasmically diffused. High beclin 1 and LC3A reactivity was related to tumor hypoxia, as this was inferred from the intense expression of HIF1α and lactate dehydrogenase 5, whereas low beclin 1 and LC3A expression was linked with an increased vascular density. In addition, beclin 1 was related to disease-specific survival which, however, exposed a biphasic pattern. A strong beclin 1 expression extending over a tumor area of more than 50% (high) was associated with an increased rate of early deaths, whereas a similarly strong, but less-extensive cytoplasmic reactivity (<10% tumor area; low) defined a sharp fall in the survival 5 years after surgery. Furthermore, the low beclin 1 expression was associated with high Breslow's depth, high Clark's level, and ulceration. Low LC3A expression was also related to ulceration, but not to other histopathological features nor prognosis. In multivariate analysis, beclin 1 was an independent prognostic variable. It is concluded that extensive autophagic activity is generated by tumor hypoxia and anaerobic glycolysis, whereas angiogenesis maintains low autophagic activity. Atg6/beclin 1 was proved to be capable of deciphering the prognosis in cutaneous malignant melanoma, but the matter requires further investigation.  相似文献   
107.
108.
OBJECTIVE: To investigate the correlation between the early follicular phase serum inhibin B levels and other indicators of ovarian reserve. STUDY DESIGN: Seventy-four women aged 24-40 years (mean 32) with different infertility etiologies were investigated in the early follicular phase of a spontaneous mentrual cycle. The volume of the ovaries was measured and the total number of follicles <5 mm in size counted by ultrasound. Serum levels of FSH, estradiol (E2) and inhibin B were measured on the same day. In stepwise regression analysis inhibin B levels were correlated with age, body-mass-index, the ultrasound measurements, cause of infertility, parity, FSH and E2. RESULTS: FSH, BMI and the number of follicles proved to be statistically significant independent predictive factors for the inhibin B levels, FSH and BMI correlating negatively and the number of follicles positively with inhibin B serum concentrations. CONCLUSION: The number of small follicles reflect the inhibin B production of the ovaries. BMI being as strong predictive factor of inhibin B levels as FSH could in part explain the impaired likelihood of conceiving in obese patients.  相似文献   
109.
A rare case of sirenomelia at 38 weeks of gestation is reported. Fusion of the lower extremities and incomplete development of the bony pelvis was associated with agenesis of the urinary and genital systems, anorectal atresia and a single large umbilical artery. There was complete situs inversus of the single lower limb. This was composed of two partially fused femurs, a common tibia without fibula, and a rudimentary foot having three metatarsal bones and their corresponding toes. The present case was also interesting for its association with hypoplasia of the lungs. The pathogenesis of sirenomelia is discussed.  相似文献   
110.
PURPOSE: Although the role of radiotherapy (RT) after mastectomy in reducing the local relapse rate is well established, its impact on overall survival is strongly questioned. Up to 70% of patients will not benefit from additional RT, and a "wait and see" policy is often adopted. Establishment of short, still safe, and effective RT regimens would render adjunctive radiotherapy more appealing. We evaluated the toxicity and efficacy of a Hypofractionated and intensively Accelerated RT regimen supported with amifostine Cytoprotection (HypoARC) in a cohort of 72 high-risk breast cancer patients treated with modified mastectomy or conservative surgery and FEC (5-fluorouracil/epirubicin/cyclophosphamide) chemotherapy. PATIENTS AND METHODS: A high dose of amifostine, 1,000 mg, was given as a 5-min i.v. infusion before each of the 12 consecutive fractions of RT (4 x 3.5 Gy/fraction and 8 x 4 Gy/fraction, 1 fraction/day, 5 fractions/week). The breast or chest wall, as well as supraclavicular and axillary area, was included in the RT fields. The follow-up of patients ranged from 18 to 42 months (median, 28 months). Alkaline phosphatase (AF) expression was assessed immunohistochemically in normal and cancerous breast tissues. RESULTS: Ninety-two percent of patients successfully completed the regimen, the only side effects being mild nausea and asthenia. In 7% of patients, amifostine was interrupted because of a rash/fever reaction. A dramatic reduction in acute skin toxicity was noted (p < 0.0001). Acute pneumonitis, as well as late toxicity in breast, chest wall, axillary, and lung tissue, was lower with the HypoARC regimen, although not significantly, than with the standard fractionation regimen used to treat two matched control cohorts. Both HypoARC and standard RT significantly reduce the local relapse rate (p < 0.0001), although the local relapse-free and overall survival times were marginally better for the HypoARC group of patients (p > 0.09). AF showed a mixed nuclear/cytoplasmic pattern of expression in the epithelial, endothelial, and stromal component of the normal breast and benign lesions, whereas an impressive loss of AF expression was noted in in situ and invasive breast cancer and tumoral stroma. CONCLUSIONS: The HypoARC regimen is convenient for both patients and radiotherapy departments. The regimen is well tolerated and shows a significantly better profile in terms of early toxicity; a reduced rate of late sequel may be expected. The local relapse rate is as low as that expected from conventional RT. The absence of AF expression in cancer cells and tumoral stroma is probably a major reason for the selective protection of normal breast tissue by amifostine.  相似文献   
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