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BACKGROUND: Radiation-induced soft tissue sarcomas (RI-STS) are rare, and it is believed that they are associated with a poor prognosis.The authors of this report compared the clinical and functional outcomes of adults who had extremity RI-STS with the outcomes of adults with sporadic STS. METHODS: Forty-four patients who were diagnosed with RI-STS from 1989 to 2009 were identified from 4 prospectively collected databases. Patient demographics, surgical and adjuvant treatment parameters, and oncologic and functional outcomes were evaluated. RESULTS: The median latent period from irradiation of the primary condition to RI-STS diagnosis was 16 years. The median radiotherapy dose used for the index condition was 45 gray. The median age at RI-STS diagnosis was 56 years. The most common primary diagnoses were breast cancer (36.4%) and lymphoma (34.1%). The most common RI-STS histologies were malignant fibrous histiocytoma (36.4%) and angiosarcoma (18.2%). Forty-two patients underwent surgery, 13 patients received adjuvant radiotherapy, and 8 patients received adjuvant chemotherapy. Systemic metastases occurred in 50% of treated patients (n = 21), and 26% (n = 11) developed local recurrence, the risk of which was lower among patients who received reirradiation (P = .043). The 5-year disease-free interval (DFI) and overall survival (OS) rates for patients with RI-STS who presented without metastasis were 36% and 44%, respectively. Patients who had International Union Against Cancer TNM stage III RI-STS had a significantly worse DFI compared with patients who had stage III sporadic STS (multivariate analysis, P = .051). Eighteen patients with RI-STS underwent functional assessment after surgery, and their results were comparable to those of patients with sporadic STS. CONCLUSIONS: Despite aggressive surgical treatment, patients who have RI-STS remain at greater risk of both local and systemic recurrence compared with patients who have sporadic STS, but they can anticipate similar functional outcomes. Reirradiation can be relatively safe and effective if used properly. Cancer 2011. © 2011 American Cancer Society.

Pathological fractures of the humerus are associated with pain, morbidity, loss of function and a diminished quality of life. We report our experience of stabilising these fractures using polymethylmethacrylate and non-locking plates. We undertook a retrospective review over 20 years of patients treated at a tertiary musculoskeletal oncology centre. Those who had undergone surgery for an impending or completed pathological humeral fracture with a diagnosis of metastatic disease or myeloma were identified from our database. There were 63 patients (43 men, 20 women) in the series with a mean age of 63 years (39 to 87). All had undergone intralesional curettage of the tumour followed by fixation with intramedullary polymethylmethacrylate and plating. Complications occurred in 14 patients (22.2%) and seven (11.1%) required re-operation. At the latest follow-up, 47 patients (74.6%) were deceased and 16 (25.4%) were living with a mean follow-up of 75 months (1 to 184). A total of 54 (86%) patients had no or mild pain and 50 (80%) required no or minimal assistance with activities of daily living. Of the 16 living patients none had pain and all could perform activities of daily living without assistance. Intralesional resection of the tumour, filling of the cavity with cement, and plate stabilisation of the pathological fracture gives immediate rigidity and allows an early return of function without the need for bony union. The patient’s local disease burden is reduced, which may alleviate tumour-related pain and slow the progression of the disease. The cemented-plate technique provides a reliable option for the treatment of pathological fractures of the humerus.

In medical research, commonly, one is interested in the time to the occurrence of a particular event, such as the revision of an implant, and the analysis of these data is referred to as survival analysis. However, for some patients, the event is not observed and their observations are censored. These censored observations are particular to survival data and require specific methods for estimation. The Kaplan and Meier method is a popular method to estimate the probability of being free of the event over time and it is now widely applied in orthopaedics such as to report implant survival. However, one of the assumptions underlying the Kaplan-Meier estimator implies that patients whose observations are censored have the same risk of occurrence of the event than patients remaining in the study. However, because the revision of an implant cannot occur after a patient dies, and that dead patients have their observations censored in the Kaplan-Meier method, another setting must be considered. In the sequel we will demonstrate the inadequacy of the Kaplan-Meier method to estimate implant survival and detail the cumulative incidence estimator.

The cumulative summation (CUSUM) test is increasingly being used in medicine to monitor a wide variety of processes such as cardiac surgery or disease outbreaks. The CUSUM sequentially tests the null hypothesis that the process is in control, i.e. its mean is equal to a given target. Thus, it detects when the process changes to an out of control state. Conversely, monitoring the learning curve requires detecting the time when the process reaches an in control state. In this work we develop an alternative to the CUSUM, the learning curve CUSUM (LC-CUSUM), that serves to detect when a process deviates from an out of control state to an in control state. The test is based on a two one-sided tests procedure where the null hypothesis is that the process is out of control. This can be written as H(0): |mu-mu(0)|> or =delta tested against H(1): |mu-mu(0)|< delta. The null hypothesis is thus the union of two one-sided hypotheses and is rejected when both are rejected. A CUSUM test statistic is then constructed for each hypothesis in a traditional way. The properties of the test are investigated through numerical simulations, and are illustrated on the learning curve of an endoscopist performing endoscopic retrograde cholangiopancreatographies for biliary tract disorders.

Background The learning curve cumulative sum (LC-CUSUM) test is an innovative tool that allows quantitative monitoring of individual medical performance during the learning process by determining when a predefined acceptable level of performance is reached. This study used the LC-CUSUM test to monitor the learning process and failure rate of anesthesia residents training for specific subspecialty anesthesia procedures. Methods The study included 490 tracheal punctures (TP) for jet ventilation, 340 thoracic epidural analgesia (TEA) procedures, and 246 fiberoptic nasal intubations (FONI) performed by 18 residents during their single 6-month rotation. Results Overall, 27 (14–52), 19 (5–41), and 14 (6–33) TP, TEA, and FONI procedures were performed, respectively, by each resident. In total, 2 of 18 residents achieved an acceptable failure rate for TEA according to the literature and 4 of 18 achieved an acceptable failure rate for FONI, while none of the residents attained an acceptable rate for TP. Conclusions A single 6-month rotation in a reference teaching center may not be sufficient to train residents to perform specific or sub-specialty procedures as required. A regional learning network may be useful. More patient-based data are necessary to conduct a risk adjustment analysis for such specific procedures.

The aims of this study were to determine if the learning curve cumulative summation test (LC-CUSUM) can differentiate proficiency in placing intravenous catheters by novice learners, and identify the cause of failure when it occurred. In a prospective, observational study design 6 undergraduate students with no previous experience of placing intravenous catheters received standardized training by a board certified veterinary anesthesiologist in intravenous catheter placement technique. Immediately following training, each student attempted 60 intravenous catheterizations in a dog mannequin thoracic limb model. Results were scored as a success or failure based upon completion of four specific criteria, and where catheter placement failure occurred, the cause was recorded according to pre-defined criteria. Initial acceptable and unacceptable failure rates were set by the study team and the LC-CUSUM was used to generate a learning curve for each student. Using 10% and 25% acceptable and unacceptable failure rates, 3 out of 6 students attained proficiency, requiring between 26 to 48 attempts. Applying 25% and 50% acceptable and unacceptable failure rates, 5 of 6 students obtained proficiency, requiring between 18 and 55 attempts. Wide inter-individual variability was observed and the majority of failed catheterisation attempts were limited to two of the four pre-defined criteria. These data indicate that the LC-CUSUM can be used to generate individual learning curves, inter-individual variability in catheter placement ability is wide, and that specific steps in catheter placement are responsible for the majority of failures. These findings may have profound implications for how we teach and assess technical skills.

The aims of this study were to determine if the learning curve cumulative summation test (LC-CUSUM) can differentiate proficiency in placing intravenous catheters by novice learners, and identify the cause of failure when it occurred. In a prospective, observational study design 6 undergraduate students with no previous experience of placing intravenous catheters received standardized training by a board certified veterinary anesthesiologist in intravenous catheter placement technique. Immediately following training, each student attempted 60 intravenous catheterizations in a dog mannequin thoracic limb model. Results were scored as a success or failure based upon completion of four specific criteria, and where catheter placement failure occurred, the cause was recorded according to pre-defined criteria. Initial acceptable and unacceptable failure rates were set by the study team and the LC-CUSUM was used to generate a learning curve for each student. Using 10% and 25% acceptable and unacceptable failure rates, 3 out of 6 students attained proficiency, requiring between 26 to 48 attempts. Applying 25% and 50% acceptable and unacceptable failure rates, 5 of 6 students obtained proficiency, requiring between 18 and 55 attempts. Wide inter-individual variability was observed and the majority of failed catheterisation attempts were limited to two of the four pre-defined criteria. These data indicate that the LC-CUSUM can be used to generate individual learning curves, inter-individual variability in catheter placement ability is wide, and that specific steps in catheter placement are responsible for the majority of failures. These findings may have profound implications for how we teach and assess technical skills.

The standard of care for isolated extremity osteosarcoma in adolescents and young adults has changed very little in the last twenty years1. Chemotherapeutic regimens including doxorubicin, cisplatin, and high-dose methotrexate have predominated, and the timing of treatments has also changed very little. Most patients receive some portion of their chemotherapy prior to surgical local control (termed neoadjuvant chemotherapy) and then additional adjuvant chemotherapy following surgical resection. As so much of this care standard has been subjected to repeated evaluation in randomized controlled clinical trials1, it may be assumed that the timing of treatments is similarly evidence-based. It is not. The timing of treatments is instead rational, based on the following four considerations that led to its development and incorporation into common practice. First, early in the days of limb salvage surgery, neoadjuvant chemotherapy was undertaken to delay definitive surgery to permit the fabrication of the custom endoprosthetic implants then used for limb salvage reconstructions. Second, neoadjuvant chemotherapy permitted measurement of the treatment effect on the primary tumor2 in the form of preoperative chemotherapy-induced tumor necrosis, thereby providing a surrogate measure of chemotherapeutic response and eradication of clinically undetectable microscopic metastatic disease. Third, treating physicians thought that initiating systemic treatments quickly put priorities in proper philosophical order, with an upfront attack on the deadly presumed systemic disease, rather than an initial focus on the primary tumor and local control. Fourth, surgeons preferred performing close-margin resections around tumors that had been largely treated already. Often-touted potentially advantageous treatment effects of neoadjuvant chemotherapy included tumor size reduction, clearing of peritumoral edema on magnetic resonance imaging (MRI) scans, development of a rind or pseudocapsule, and increased palpable firmness of the tumor. The first rationale has largely disappeared now that modular implants and large regional and national allograft tissue repositories are available. The second rationale remains, but provides only prognostic information rather than treatment guidance, as changing protocols following a poor histological response (limited tumor necrosis) to preoperative chemotherapy does not improve prognosis3. In a Pediatric Oncology Group study beginning in the late 1980s, investigators attempted to provide evidence for the third rationale, but the study was closed after years of insufficient patient accrual4. The reason suspected for the poor enrollment was that many surgeons already believed too firmly in the fourth rationale to enroll their patients for possible randomization to the immediate-surgery arm when limb salvage was planned. Although they failed to reach significance, the published results trended toward improved survival in the immediate-surgery group4. This study’s underpowered results did not slow the acceptance of neoadjuvant chemotherapy as the standard of care for patients with osteosarcoma. Thus, even the lack of data for the third rationale is the result of the yet unstudied fourth rationale, that neoadjuvant chemotherapy makes local control surgery easier or safer. While a number of modalities have been tested with regard to their value in noninvasively measuring the treatment effect of neoadjuvant chemotherapy on the primary tumor prior to local control surgery, no modality has been sufficiently successful at predicting the treatment effect to be widely adopted by sarcoma treatment centers5-14. While evaluation of changes between pre-chemotherapy and post-chemotherapy MRIs has not proven to accurately predict histologically confirmed treatment effects, these MRIs are still almost universally used by surgeons to plan local control resections15. Furthermore, MRI is the most accurate noninvasive means of staging the local bone and soft-tissue extent of sarcomas, including compartmental spread, neurovascular involvement, and intra-articular spread16-22. We investigated the effect of neoadjuvant chemotherapy on MRI-based surgical planning for osteosarcoma. Even a tumor that has responded well to preoperative chemotherapy in terms of histological necrosis may have progressed with regard to surgically critical anatomy. This study was undertaken to evaluate the surgically important anatomic effects of neoadjuvant chemotherapy. Because the practice standard of neoadjuvant chemotherapy was deeply entrenched and we had no reason to believe that it was erroneous, we thought that it was both impractical and unethical to randomize patients to immediate surgery or neoadjuvant chemotherapy followed by surgery. Instead we chose to evaluate the practice in a pilot study using available data from existent MRIs. In order to measure surgically important anatomic changes on these MRIs, we developed a surgical planning questionnaire focused on the distal part of the femur, assessed its reliability across different surgeons, and tested it against a separate validation in the form of radiologists assessing the same MRIs with their own anatomic details questionnaire. With this tool, we could then safely ask our question: does neoadjuvant chemotherapy change the surgical resections planned by surgeons for distal femoral osteosarcomas?

Quality control is receiving increasing attention from surgeons as a key to meeting the needs of patients and the requirements of health care authorities. The objective of the study was to evaluate a continuous monitoring program for surgical performance in anterior cruciate ligament reconstruction. We measured the differential anterior knee laxity immediately after anterior cruciate ligament reconstruction by two experienced surgeons. Surgical technique including the choice of ancillary devices and implant material was at the surgeon’s discretion. The target was an immediate postoperative differential knee laxity at 20° of knee flexion of −1.5 mm. The cumulative summation test (CUSUM) was used to detect inadequate performance. Seventy-nine consecutive patients were included in the study. Median postoperative differential knee laxity at 20° flexion was −2 mm (interquartile range −4 to 0 mm; SD = 2.3). The CUSUM test at 20° knee flexion emitted an alarm at the 12th procedure, indicating that performance was inadequate with a tendency for laxity to be above the target of −1.5 mm. Two alarms were emitted after the 28th procedure, indicating that laxity tended to be below the target. Monitoring of immediate postoperative differential anterior knee laxity in anterior cruciate ligament reconstruction is feasible and can provide useful information on actual surgeon performance. Clinical relevance: continuous monitoring of the quality of anterior cruciate ligament reconstruction may help surgeons to detect deviations from optimal performance when new surgical techniques and innovative fixation devices are introduced.

Our objective was to determine the reproducibility and validity of urine retention volumes measured by 3D ultrasonography (3D-US) 2 h postpartum. This was a longitudinal prospective study of 100 women who delivered vaginally. Each woman underwent five successive urine retention measurements with the Bladder Scan 2 h after vaginal delivery, followed by transurethral catheterization to determine the real volume. The reproducibility of only the last four scan values was analyzed with an intraclass correlation coefficient, and that of determinations 4 and 5 with a Bland-Altman plot. The validity of the device was similarly evaluated using the mean four-scan and real values. Pearson's correlation coefficient was calculated and a least-trimmed squares robust linear-regression model was used. All tests were two-sided with a 5% alpha risk. Results showed that 3D-US measurements were highly reproducible, with an intraclass correlation coefficient of 0.974 (95% CI:0.964-0.981). 3D-US also accurately estimated the real urine volume (intraclass correlation coefficient 0.924; 95% CI:0.888-0.949), but tended to underestimate by about 6.8%. The between-technique Pearson correlation coefficient was 0.94 (P0.0001) and the regression analysis gave an R2 of 0.914. Urine retention volumes exceeded 500 ml in 55 women, and 11 in 7. We concluded that 3D-US was reliably able to measure postpartum urine retention volume.