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991.
992.
Objectives:To determine the relative effects of Herbst appliance therapy in hypo- and hyperdivergent patients.Materials and Methods:The treated group included 45 growing Class II, division 1, patients treated with stainless steel crown Herbst appliances, followed by fixed edgewise appliances. The untreated control group consisted of 45 Class II, division 1, subjects, matched to the treated sample based on Angle classification, age, sex, and pretreatment mandibular plane angle (MPA). Subjects were categorized as hypo- or hyperdivergent based on their MPAs. Pre- and posttreatment cephalograms were traced and superimposed on cranial base and mandibular structures.Results:The primary effect of the Herbst in terms of maxillomandibular correction was in the maxilla. It significantly restricted maxillary growth, producing a “headgear effect.” Mandibular treatment changes depended on divergence. Hyperdivergent patients experienced a deleterious backward true mandibular rotation with Herbst treatment. Hypodivergent patients, as well as untreated hypo- and hyperdivergent controls, underwent forward true mandibular rotation. However, hypodivergent chins did not advance any more than expected for untreated hypodivergent Class II patients.Conclusions:Hypo- and hyperdivergent patients benefit from the Herbst''s headgear effect. While the mandibular growth of hypodivergent patients overcomes the negative rotational effects, hyperdivergent patients undergo a deleterious backward mandibular rotation and increases in facial height.  相似文献   
993.
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Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? High‐grade prostate cancers are associated with poor disease‐specific outcomes. A proportion of these tumours produce little PSA. This study demonstrates that among Gleason 8–10 prostate cancers, some of the worst survival outcomes are associated with the lowest PSA levels.

OBJECTIVE

  • ? To assess outcomes of patients with Gleason score 8–10 prostate cancer (CaP) with a low (≤2.5 ng/mL) vs higher preoperative serum PSA levels.

PATIENTS AND METHODS

  • ? From 1983 to 2003, 5544 patients underwent open radical prostatectomy, of whom 354 had a Gleason 8–10 tumour in the prostatectomy specimen.
  • ? Patients were stratified according to preoperative PSA level into four strata: ≤2.5 ng/mL (n= 31), 2.6–4 ng/mL (n= 31), 4.1–10 ng/mL (n= 174), and >10 ng/mL (n= 118).
  • ? We compared biochemical progression‐free survival (PFS), metastasis‐free survival (MFS), and cancer‐specific survival (CSS) as a function of preoperative PSA level.

RESULTS

  • ? Patients with PSA level ≤2.5 ng/mL were more likely to have seminal vesicle invasion (P= 0.003).
  • ? On Kaplan–Meier survival analysis, patients with a PSA level ≤2.5 ng/mL had proportionately worse outcomes than their counterparts with higher PSA levels.
  • ? The 7‐year PFS in the PSA ≤2.5 ng/mL stratum was lower than those of the PSA 2.6–4 ng/mL and 4–10 ng/mL strata (36% vs 50 and 42%, respectively); however, the lowest 7‐year PFS was found in those with a PSA level >10 ng/mL (32%, P= 0.02).
  • ? Gleason score 8–10 tumours with a PSA level ≤2.5 ng/mL also tended to have the lowest 7‐year MFS (75, 93, 89 and 92% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.2) and CSS (81, 100, 94 and 90% for PSA level ≤2.5, 2.6–4, 4.1–10 and >10 ng/mL, respectively, P= 0.3), although these differences were not statistically significant.
  • ? In the subset with palpable disease, Gleason grade 8–10 disease with PSA level ≤2.5 ng/mL also was associated with a worse prognosis.

CONCLUSIONS

  • ? In patients with Gleason grade 8–10 disease, a proportion of these tumours are so poorly differentiated that they produce relatively little PSA.
  • ? Patients with high‐grade, low‐PSA tumours had less favourable outcomes than many of those with higher PSA levels.
  相似文献   
999.
Study Type – Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Only 30–35% of patients with positive surgical margins after radical prostatectomy develop recurrent disease. Adjuvant radiotherapy reduces the rate of biochemical relapse or metastasis and improves overall survival after radical prostatectomy. Various pathological factors, such as location and extent of positive margins, have been proposed as possible prognostic factors in men with margin‐positive prostate cancer, however, the recent International Society of Urological Pathology consensus meeting in Boston noted that there is limited data on the significance of Gleason grade of the carcinoma at a positive margin. The present study shows that the presence of high grade prostate cancer, i.e. Gleason pattern 4 or 5, at a positive surgical margin is an independent predictor of biochemical recurrence after radical prostatectomy. Moreover, patients with lower grade carcinoma at the margin have a similar prognosis to men with negative margins. Hence, assessment of Gleason grade at the site of positive margin may aid optimal selection of patients for adjuvant radiotherapy.

OBJECTIVE

  • ? To establish predictors of biochemical recurrence by analysing the pathological characteristics of positive surgical margins (PSMs), including Gleason grade of the carcinoma at the involved margin.

PATIENTS AND METHODS

  • ? Clinicopathological and outcome data on 940 patients who underwent radical prostatectomy (RP) between 1997 and 2003 were collected.
  • ? Of these, 285 (30.3%) patients with PSMs were identified for pathological review, including assessment of location of margin, linear extent, number of PSMs, plane of margin and Gleason grade (3 vs 4 or 5) at the margin.

RESULTS

  • ? At a median follow‐up of 82 months, the biochemical recurrence rate of the PSM cohort was 29%.
  • ? On univariate analysis, the presence of Gleason grade 4 or 5 at the margin (34.4% of cases) was significantly associated with biochemical recurrence (hazard ratio [HR] 2.80, 95% confidence interval [CI]= 1.82–4.32, P < 0.001) compared with the presence of Gleason grade 3.
  • ? Linear extent of margin involvement was also associated with recurrence (P= 0.009).
  • ? Single vs multiple margin involvement, location, and plane of the involved margin were not significant predictors of recurrence.
  • ? On multivariate analysis, Gleason grade 4 or 5 at the margin remained an independent predictor of recurrence (HR 2.14, 95% CI = 1.29–4.03, P= 0.003).

CONCLUSION

  • ? The Gleason grade at the site of a PSM identifies patients at increased risk of biochemical recurrence and should aid stratification of patients for adjuvant radiation therapy.
  相似文献   
1000.
Study Type – Prognosis (cohort) Level of Evidence 2a What's known on the subject? and What does the study add? Men fail active surveillance for a variety of reasons; however, no single reliable biomarker has been found to date which will identify these men from the outset. We know that there are about 35 prostate cancer risk alleles which have been discovered to influence risk of prostate cancer, from large‐scale genome‐wide association studies. Some of these have been associated with aggressive prostate cancer. Nobody has examined the potential for these risk alleles to predict men who might fail active surveillance. This study adds to the growing evidence that single nucleotide polymorphisms may be able to identify men who have aggressive prostate cancers, and that this could be part of a risk algorithm used in active surveillance protocols.

OBJECTIVE

  • ? To assess whether the carrier status of 35 risk alleles for prostate cancer (CaP) is associated with having unfavourable pathological features in the radical prostatectomy specimen in men with clinically low risk CaP who fulfil commonly accepted criteria as candidates for active surveillance.

PATIENTS AND METHODS

  • ? We studied men of European ancestry with CaP who fulfilled the commonly accepted clinical criteria for active surveillance (T1c, prostate‐specific antigen <10 ng/mL, biopsy Gleason ≤6, three or fewer positive cores, ≤50% tumour involvement/core) but instead underwent early radical prostatectomy.
  • ? We genotyped these men for 35 CaP risk alleles. We defined ‘unfavourable’ pathological characteristics to be Gleason ≥7 and/or ≥ pT2b in their radical prostatectomy specimen.

RESULTS

  • ? In all, 263 men (median age 60 [46–72] years) fulfilled our selection criteria for active surveillance, and 58 of 263 (22.1%) were found to have ‘unfavourable’ pathological characteristics.
  • ? The frequencies of three CaP risk alleles (rs1447295 [8q24], P= 0.004; rs1571801 [9q33.2], P= 0.03; rs11228565 [11q13], P= 0.02) were significantly higher in men with ‘unfavourable’ pathological characteristics.
  • ? Two other risk alleles were proportionately more frequent (rs10934853 [3q21], P= 0.06; rs1859962 [17q24], P= 0.07) but did not achieve nominal statistical significance.
  • ? Carriers of any one of the significantly over‐represented risk alleles had twice the likelihood of unfavourable tumour features (P= 0.03), and carriers of any two had a sevenfold increased likelihood (P= 0.001).
  • ? Receiver–operator curve analysis demonstrated an area under the curve of 0.66, suggesting that the number of single nucleotide polymorphisms carried provided discrimination between men with ‘favourable’ and ‘unfavourable’ tumour features in their prostatectomy specimen.

CONCLUSION

  • ? In potential candidates for active surveillance, certain CaP risk alleles are more prevalent in patients with ‘unfavourable’ pathological characteristics in their radical prostatectomy specimen.
  相似文献   
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