Is there any advantage in placing an additional calcar screw in locked nailing of proximal humeral fractures?

BACKGROUND

The objective of this study was to evaluate the biomechanical effect of an additional unlocked calcar screw compared to a standard setting with three proximal humeral head screws alone for fixation of an unstable 2-part fracture of the surgical neck.

HYPOTHESIS

The additional calcar screw improves stiffness and failure load.

METHODS

Fourteen fresh frozen humeri were randomized into two equal sized groups. An unstable 2-part fracture of the surgical neck was simulated and all specimens were fixed with the MultiLoc(®)-nail. Group I represented a basic screw setup, with three locked head screws and two unlocked shaft screws. Group II was identical with a supplemental unlocked calcar screw (CS). Stiffness tests were performed in torsional loading, as well as in axial and in 20° abduction/20° adduction modes. Subsequently cyclic loading and load-to-failure tests were performed. Resulting stiffness, displacement under cyclic load and ultimate load were compared between groups using the t-test for independent variables (α=0.05).

RESULTS

No significant differences were observed between the groups in any of the biomechanical parameters. Backing out of the CS was observed in three cases.

DISCUSSION

The use of an additional unlocked calcar screw does not provide mechanical benefit in locked nailing of an unstable 2-part fracture of the surgical neck.

Survival after neoadjuvant chemotherapy with or without bevacizumab or everolimus for HER2-negative primary breast cancer (GBG 44-GeparQuinto)†

BACKGROUND

The GeparQuinto study showed that adding bevacizumab to 24 weeks of anthracycline-taxane-based neoadjuvant chemotherapy increases pathological complete response (pCR) rates overall and specifically in patients with triple-negative breast cancer (TNBC). No difference in pCR rate was observed for adding everolimus to paclitaxel in nonearly responding patients. Here, we present disease-free (DFS) and overall survival (OS) analyses.

PATIENTS AND METHODS

Patients (n = 1948) with HER2-negative tumors of a median tumor size of 4 cm were randomly assigned to neoadjuvant treatment with epirubicin/cyclophosphamide followed by docetaxel (EC-T) with or without eight infusions of bevacizumab every 3 weeks before surgery. Patients without clinical response to EC ± Bevacizumab were randomized to 12 weekly cycles paclitaxel with or without everolimus 5 mg/day. To detect a hazard ratio (HR) of 0.75 (α = 0.05, β = 0.8) 379 events had to be observed in the bevacizumab arms.

RESULTS

With a median follow-up of 3.8 years, 3-year DFS was 80.8% and 3-year OS was 89.7%. Outcome was not different for patients receiving bevacizumab (HR 1.03; P = 0.784 for DFS and HR 0.974; P = 0.842 for OS) compared with patients receiving chemotherapy alone. Patients with TNBC similarly showed no improvement in DFS (HR = 0.99; P = 0.941) and OS (HR = 1.02; P = 0.891) when treated with bevacizumab. No other predefined subgroup (HR+/HER2-; locally advanced (cT4 or cN3) or not; cT1-3 or cT4; pCR or not) showed a significant benefit. No difference in DFS (HR 0.997; P = 0.987) and OS (HR 1.11; P = 0.658) was observed for nonearly responding patients receiving paclitaxel with or without everolimus overall as well as in subgroups.

CONCLUSIONS

Long-term results, in opposite to the results of pCR, do not support the neoadjuvant use of bevacizumab in addition to an anthracycline-taxane-based chemotherapy or everolimus in addition to paclitaxel for nonearly responding patients.

CLINICAL TRIAL NUMBER

NCT 00567554, www.clinicaltrials.gov.

Mechanisms of antihyperglycaemic action of efaroxan in mice: time for reappraisal of α2A-adrenergic antagonism in the treatment of type 2 diabetes?

AIMS/HYPOTHESIS

Inspired by recent speculation about the potential utility of α(2A)-antagonism in the treatment of type 2 diabetes, the study examined the contribution of α(2)-antagonism vs other mechanisms to the antihyperglycaemic activity of the imidazoline (±)-efaroxan.

METHODS

Effects of the racemate and its pure enantiomers on isolated pancreatic islets and beta cells in vitro, as well as on hyperglycaemia in vivo, were investigated in a comparative manner in mice.

RESULTS

In isolated perifused islets, the two enantiomers of efaroxan were equally potent in counteracting inhibition of insulin release by the ATP-dependent K(+) (K(ATP)) channel-opener diazoxide but (+)-efaroxan, the presumptive carrier of α(2)-antagonistic activity, was by far superior in counteracting inhibition of insulin release by the α(2)-agonist UK14,304. In vivo, (+)-efaroxan improved oral glucose tolerance at 100-fold lower doses than (-)-efaroxan and, in parallel with observations made in vitro, was more effective in counteracting UK14,304-induced than diazoxide-induced hyperglycaemia. The antihyperglycaemic activity of much higher doses of (-)-efaroxan was associated with an opposing pattern (i.e. with stronger counteraction of diazoxide-induced than UK14,304-induced hyperglycaemia), which implicates a different mechanism of action.

CONCLUSIONS/INTERPRETATION

The antihyperglycaemic potency of (±)-efaroxan in mice is almost entirely due to α(2)-antagonism, but high doses can also lower blood glucose via another mechanism. Our findings call for reappraisal of the possible clinical utility of α(2A)-antagonistic compounds in recently identified subpopulations of patients in which a congenitally higher level of α(2A)-adrenergic activation contributes to the development and pathophysiology of type 2 diabetes.

[Traumatic optic nerve neuropathy. Longterm results following microsurgical optic nerve decompression]

BACKGROUND

Traumatic optic nerve neuropathy (TON) is defined as injury to the optic nerve with subsequent vision loss due to head or craniocerebral trauma. The treatment of this disease is the subject of controversial discussions. The purpose of the present study was to investigate pre- and immediate postoperative visual acuity in patients with unilateral TON and to compare the results with the time interval between trauma and surgical intervention.

PATIENTS AND METHODS

A total of 20 patients with unilateral TON and considerable vision loss were examined. All were treated with high dose corticoids and underwent microsurgical optic nerve decompression. Visual acuity was determined pre- and postoperatively. In long-term follow-up visual acuity was determined 3 months postoperatively.

RESULTS

Postoperatively, nine patients (45%) achieved an improvement in visual acuity of more than 0.4, and another three patients (15%) an improvement of ≥0.2. At 3 months postoperatively another four patients achieved a further improvement of their visual acuity of >0.2. A decrease in visual acuity was not observed in any case, nor were major surgical complications.

CONCLUSIONS

Factors which predict good prognosis for vision recovery include a short time interval between trauma and intervention, edema, and/or hematoma of the optic nerve sheath. Factors which predict a worse prognosis are a fracture line directly through the nerve canal, a time period between trauma and intervention of more than 24 h, and initial complete amaurosis.

Intraoperative radiotherapy (IORT) with low-energy x-rays for breast cancer

607

Background: IORT for breast cancer using either electrons or low-energy x-rays is of increasing interest over the last few years. In our institution, IORT is delivered by a mobile x-ray source (Intrabeam™) producing isotropic 50 kV x-ray fields. Because this treatment method includes single high doses to the normal breast tissue, careful and long-term evaluation of early and late toxicity is mandatory. To date there are still fewdata on long-term follow-up of patients treated with low-energy x-rays. Methods: Between 2/02 and 12/06 204 breast cancer patients received IORT either as a tumour-bed boost (133) followed by 46 Gy external beam radiotherapy (EBRT) or as partial breast irradiation (PBI) only (71). Median age was 66.4 years (35–95), median tumour size was 9 mm (1–45). Spherical applicators (median 4. 0 cm) were inserted into the tumour-cavity and a single dose of 20 Gy was given. Follow-up (f/u) included physical examination and ultrasound 1 week, 2 months, then every 6 months after therapy and mammography at yearly intervals. Radiobiological modelling of the expected spatial distribution of late reactions was done for typical cases using the linear-quadratic model with special consideration of relative biological effectiveness, spatial dose distribution and dose rate. Results: Median f/u was 28 months (1–56). Minor postoperative side effects included erythema (5%), delayed wound healing (4%), mastitis (1%) and hematoseroma (4%). A fibrotic induration of the tumour bed was observed in 9, 18, 24, 23, 26% and 24% of the patients at 2, 6 12, 24, 36 and 48 month f/u. These fibrosis rates were distributed equally in both groups. Reoperation was required in 2 patients after 10 (fibrosis) and 12 months (fat necrosis). Conclusions: Although two thirds of the patients were treated with a combination of IORT and EBRT, acute reactions in all patients were mild. A fibrotic induration confined to the tumourbed was observed in up to 25% of all patients after 2 years. The low level of clinically observed late reactions so far is in agreement with predictions from radiobiological modelling.

No significant financial relationships to disclose.

Classification of patients with a clinically isolated syndrome based on signs and symptoms is supported by magnetic resonance imaging results

BACKGROUND

Recently, a clinical classification system was described to determine whether symptoms and signs of patients presenting with a first episode suggestive of multiple sclerosis (MS) indicate the presence of monofocal or multifocal disease.

OBJECTIVES

To evaluate the value of this new classification system by comparing the results with those of simultaneously obtained magnetic resonance imaging (MRI) scans.

METHODS

The 487 patients, randomised in the BENEFIT study, were centrally assessed using the new system and classified as monofocal or multifocal, based on clinical information by two neurologists masked for the MRI results. MRI analyses were performed by expert readers masked for the clinical classification.

RESULTS

Patients classified as multifocal had more T2 hyperintense (median: 21 versus 15.5) and more T1 hypo-intense lesions (median: 2 versus 1) than those classified as monofocal. Patients classified at the local site as having evidence of a single clinical lesion, but reclassified centrally as having a clinical multifocal central nervous system presentation, had more T2 lesions than monofocal patients. In addition, patients with a multifocal presentation more often fulfilled the MRI criteria for dissemination in space, as incorporated in the International Panel (IP) diagnostic criteria for MS.

CONCLUSION

These data provide justification for the recently proposed clinical classification system to be used in patients who present with a first episode suggestive of MS, in that ;multifocal', based on symptoms and signs, is associated with more lesions on MRI.

Early mammographic and sonographic findings after intraoperative radiotherapy (IORT) as a boost in patients with breast cancer

The aim of this study was to evaluate mammographic and sonographic changes at the surgical site within the first 2 years after IORT as a boost followed by whole-breast radiotherapy (WBRT), compared with a control group treated with WBRT alone. All patients had breast-conserving surgery for early-stage breast cancer. Group A: n = 27, IORT (20 Gy) followed by WBRT (46 Gy). Group B (control group): n = 27, WBRT alone (56-66 Gy). Mammography: fat necrosis in 14 group A versus four group B patients (P < 0.001); parenchymal scarring classified as unorganized at the last follow-up in 16 vs seven cases, respectively (P = 0.03). Ultrasound: overall number of patients with circumscribed findings 27 vs 18 (P < 0.001); particular hematomas/seromas in 26 vs 13 patients (P < 0.001). Synopsis of mammography and ultrasound: overall postoperative changes were significantly higher classified in group A (P = 0.01), but not judged to have a significantly higher impact on interpretation. Additional diagnostic procedures, due to unclear findings at the surgical site, were performed on four patients of both groups. Within the first 2 years after IORT as a boost, therapy-induced changes at the original tumor site are significantly more pronounced compared with a control group. There is no evidence that the interpretation of findings is complicated after IORT.