[Investigation of the screening interval for population with negative colonoscopy examinations].

Objective: To investigate the colonscopy screening interval among patients with negative colonscopy. Methods: We selected 14 606 participants who completed the baseline and 3-year or 5-year colonoscopy examinations in the American Prostate, Lung, Colorectal, and Ovarian (PLCO) dataset as the target population. Sociodemographic characteristics (i.e., sex, age, marital status, race, and smoking), lifestyle, family history of cancer, and family history of colorectal cancer were collected. Cochran-Armitage trend analysis was used to examine whether the rate of positive cases (colorectal cancer, advanced adenoma, adenoma, and hyperplastic polyp) was increased with the length of screening interval. We compared the differences in number of detected cases, positive rates, and proportions of 3-year and 5-year screening interval strategies using internal standardization method. Results: The age of the population was （61.9±5.2） years and over half of them were males (54.4%) and 46.2% had family cancer history. The mean screening interval between the first and second endoscopies was （1 639.1±320.9） days. A total of 1 716 cases had positive endoscopic findings. With the screening interval extended, rate of the screened positive cases was also increased (P for trend<0.001). After standardized by the internal standardized population (14 606), 17.99 and 11.57 colorectal cancer cases and 177.37 and 240.35 advanced adenoma cases were detected by 3-year and 5-year screening interval strategies, respectively. Conclusion: Based on the initial screening negative population of colonoscopy in the United States, the 3-year screening interval strategy could detect a relatively large number of colorectal cancer cases, but its health and economic evaluation needs to be further explored.

Evaluation of a second-generation monoenergetic reconstruction algorithm for lesion contrast and venous invasion in pancreatic ductal adenocarcinomas.

OBJECTIVE: At lower energy levels, virtual monochromatic imaging by dual-energy computed tomography improves lesion attenuation but produces greater image noise with the conventional monoenergetic reconstruction algorithm (Mono). Recently, a second-generation algorithm (Mono+) was introduced to overcome this limitation. We compared the quality of images obtained with these algorithms and investigated the optimal energy selection for pancreatic ductal adenocarcinomas (PDACs). PATIENTS AND METHODS: Image data from 54 PDAC cases were generated at 40, 50, 60, 70, and 80 keV using Mono and Mono+. Image quality was objectively assessed by comparing the signal-to-noise ratios (SNRs), noise, and the contrast-to-noise ratios (CNRs) at different keV levels and between these algorithms at the same keV level. Lesion conspicuity and venous invasion were subjectively assessed. RESULTS: For Mono, the mean pancreas and tumour SNRs peaked at 70 keV (p<0.001). The noise increased as the energy level decreased (p<0.001). CNRtumour remained unchanged. For Mono+, the mean pancreas SNR peaked at 40 keV (p<0.001). The mean tumour SNR and noise remained unchanged. The tumour CNRs were highest at 40 keV (4.9 times the CNR of Mono 40 keV, p<0.001). Subjectively, lesion conspicuity was best at Mono+ 40 keV (p<0.001) and it showed higher diagnostic performance levels on venous invasion assessment against Mono. CONCLUSIONS: Mono+ produced better image quality, and 40 keV is recommended for the diagnosis of PDAC.

[Expression and significance of serum insulin-like growth factor-1 in patients with obstructive sleep apnea hypopnea syndrome].

Objective:To investigate the expression and significance of serum insulinlike growth factor-1(IGF-1) in adult patients with obstructive sleep apnea hypopnea syndrome(OSAHS).Method:One hundred and seven patients of OSAHS diagnosed with PSG were included in the observation group，which were divided into heavy, medium and light group according to AHI.Fifty case of healthy people without OSAHS were included in control group.Serum IGF-1 were measured by ELISA. Thirty patients of heavy OSAHS received surgery and CPAP treatment for three months,and were retested the levels of IGF-1 and PSG six months later.Result:①With the increase of OSAHS severity, the levels of serum IGF-1 were gradually decreased (F=37.732,P<0.01). There was no significant difference between mild group and healthy people (P>0.05), while there was significant differences between the remaining groups (P<0.01). ②Serum IGF-1 level has no correlation with BMI and age in OSAHS patients(P>0.05), and negatively correlated with LSaO2,and positively correlated with AHI (P<0.01). ③Serum IGF-1 levelï¼»(46.56±3.74)µg/Lï¼½ increased slightly compared with those before treatmentï¼»(42.79±4.87）µg/Lï¼½ in 30 severe patients after treatment with 3 months CPAP and regimen (P<0.01). Serum IGF-1 levelï¼»(56.61±5.46)µg/Lï¼½ increased significantly after treatment for six months; AHI level (18.72±7.36) was significantly lower than that before treatment (48.77±10.51), and LSaO2ï¼»(87.42±8.61)%ï¼½ increased significantly than that before treatmentï¼»(68.33±10.24)%ï¼½.Conclusion:OSAHS patients with decreased serum IGF-1 level may be associated with concurrent insulin resistance. Surgery combined with more than half a year of CPAP treatment can significantly reduce AHI, improve the level of LSaO2 and serum IGF-1. Serum IGF-1 levels could be used as a monitor of efficacy evaluation.

Acute myocardial infarction in young Asian women: a comparative study on Chinese, Malay and Indian ethnic groups.

INTRODUCTION: There is a paucity of data on acute myocardial infarction (AMI) in young Asian women and of comparative data among various ethnic groups with respect to risk factor profile and clinical outcomes. We present a comprehensive overview of the clinical characteristics of young Asian women with AMI and a comparative analysis among Chinese, Malay and Indian women in a multi-ethnic Asian country. METHODS: We studied 45 Asian female patients aged 50 years and below who were admitted to our hospital with a diagnosis of ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI). RESULTS: Overall, diabetes mellitus, hypertension and hyperlipidaemia were prevalent in the study population. Hyperlipidaemia was more prevalent among Indian patients, while diabetes mellitus was more common among Malay patients. Only a minority of the study patients were current smokers. Among the 20 patients admitted with STEMI, 17 (85 percent) received urgent reperfusion therapy. The mean symptom-to-balloon time and door-to-balloon time for the Malay patients were longer compared to those for other ethnic groups. Among the 25 patients admitted with NSTEMI, 12 (48 percent) underwent coronary revascularisation therapy. The average duration of hospital stay was 4 +/- 4.1 days, with no significant difference observed among the various ethnic groups. CONCLUSION: Many young Asian women with AMI have identifiable risk factors that are different from those found in the Western population. There seems to be an ethnic effect on the prevalence of these risk factors and door-to-balloon time.

Clinical observation of 73 nasopharyngeal carcinoma patients treated by helical tomotherapy: the China experience.

The preliminary short-term clinical outcome of 73 nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy at our cancer institute has been evaluated. Between September 2007 and September 2009, 73 newly diagnosed NPC patients were treated with helical tomotherapy. The distributions of clinical stages according to the UICC 2002 Staging System were: 6, 27, 24, and 16 for Stage I, IIa-b, III, and IVa-b, respectively. The prescription dose was 70-74 Gy/33F to planning gross tumor volume containing the primary tumor and positive lymph nodes, with 60-62.7 Gy/33F to high risk planning target volume, while delivering 52-56 Gy/33F to low risk planning target volume. Twenty-four patients were treated with radiation therapy as single modality, 25 with concurrent cisplatin-based chemotherapy with or without anti-EGFR monoclonal antibody therapy, and 24 with concurrent anti-EGFR monoclonal antibody therapy. Setup errors were analyzed. Side-effects were evaluated with the established RTOG/EORTC criteria. Average beam-on-time was 468.8 sec/F (396.7-696.1 sec). The setup errors in the lateral, longitudinal and vertical directions were 0.00 ± 1.79 mm, -0.55± 2.17 mm and 0.38 ± 1.43 mm, corresponding to 3.80 mm, 4.20 mm, and 2.46 mm as the CTV-PTV margin in these directions. The grade 0, 1, 2 and 3 acute skin toxicity was 2.7%, 76.7%, 13.8% and 6.8%; the grade 0, 1, 2 and 3 acute mucositis was 1.4%, 32.9%, 60.2% and 5.5%; and the grade 0, 1, 2 and 3 acute xerostomia was 4.0%, 45.3%, 50.7% and 0, respectively. Only 5 patients suffered from grade 3 or 4 leucopenia. Xerostomia resolved with passing of time and no grade 2 or more xerostomia was noted one year after radiation therapy. Concurrent chemotherapy significantly increased incidence of severe acute toxicities. One month after radiation therapy the remission rates of primary tumor and positive lymph nodes were 91.8% and 98.1%, respectively. The median follow-up was 14.8 months. The one-year relapse-free survival, distant metastasis-free survival and overall survival was 95.6%, 97.2% and 94.8%, respectively. In conclusion, the incidence of severe acute toxicities and late xerostomia was relatively infrequent for NPC patients treated with helical tomotherapy. The long-term clinical outcome for these patients is under investigation.

Clinical dosimetric study of three radiotherapy techniques for postoperative breast cancer: Helical Tomotherapy, IMRT, and 3D-CRT.

This paper is to investigate the dosimetric characteristics of Helical Tomotherapy (HT), step-and-shoot intensity-modulated radiation therapy (SaS-IMRT) and three-dimensional conformal radiation therapy (3D-CRT) for the postoperative breast cancer as well as their dosimetric comparison of the normal tissues. CT images of 10 postoperative patients with early stage breast cancer were transferred into HT, SaS-IMRT and 3D-CRT planning systems respectively after the target region and normal tissues were outlined by the same physician to assure the contour consistency. Each prescribed dose for three different modalities of plans was given to a total of 50 Gy in 25 fractions. Doses and irradiated volumes in heart, lungs, as well as conformity index (CI) and homogeneity index (HI) were evaluated for detailed comparison. All three plans showed appropriate coverage for the prescribed target dose in the dosimetric comparison. The CI in HT and SaS-IMRT as well as 3D-CRT was 0.68 ± 0.12, 0.58 ± 0.08 and 0.40 ± 0.08, respectively. The HI were 1.10 ± 0.03, 1.14 ± 0.02 and 1.17 ± 0.04, which appeared intergroup significant differences (p < 0.05). V5, V10, as well as V20 of the heart were smallest in 3D-CRT than HT and SaS-IMRT. V5 of the ipsilateral lung was the smallest in 3D-CRT than HT and SaS-IMRT (p < 0.05); However, V20 and V30 were smaller in HT and SaS-IMRT than 3D-CRT (p < 0.05). V5 of the contralateral lung was the smallest in 3D-CRT than other groups, with V10~V30 were basically similar in numeric values with not obvious discrepancy. Comparing with SaS-IMRT and 3D-CRT, HT technique in treating breast cancer had the best conformity and homogeneity index as well as steepest dose gradient due to its highly modulated beamlets with rotational technique. The heart volume irradiated was the smallest in conventional 3D-CRT, with SaS-IMRT was the largest among the three techniques, as expected. The volume of the contralateral lung irradiated was the smallest in 3D-CRT than other groups. V5 of the ipsilateral lung was the smallest in 3D-CRT than other two groups. V10~V30 in HT and SaS-IMRT were similar and better than 3D-CRT dosimetrically. We conclude that HT technique had advantages over SaS-IMRT and 3D-CRT based on the dosimetric comparison in this study, especially in the high dose region of ipsilateral lung, target homogeneity and dose uniformity.