Osteosarcoma of the pelvis

Aims

Osteosarcoma of the pelvis is a particularly difficult tumour to treat as it often presents late, may be of considerable size and/or associated with metastases when it presents, and is frequently chondroid in origin and resistant to chemotherapy. The aim of this study was to review our experience of managing this group of patients and to identify features predictive of a poor outcome.

Patients and Methods

Between 1983 and 2014, 121 patients, (74 females and 47 males) were treated at a single hospital: 74 (61.2%) patients had a primary osteosarcoma and 47 (38.8%) had an osteosarcoma which was secondary either to Paget’s disease (22; 18.2%) or to previous pelvic irradiation (25; 20.7%). The mean age of those with a primary osteosarcoma was 29.3 years (nine to 76) and their mean follow-up 2.9 years (0 to 29). The mean age of those with a secondary sarcoma was 61.9 years (15 to 85) and their mean follow-up was one year (0 to 14). A total of 22 patients with a primary sarcoma (52.4%) and 20 of those with a secondary sarcoma (47.6%) had metastases at the time of presentation.

Results

The disease-specific survival at five years for all patients was 27.2%. For those without metastases at the time of diagnosis, the five-year survival was 32.7%. Factors associated with a poor outcome were metastases at diagnosis and secondary tumours. In primary osteosarcoma, sacral location, surgical margin and a diameter > 10 cm were associated with a poor outcome.

Conclusion

In this, the largest single series of patients with an osteosarcoma of the pelvis treated in a single hospital, those with secondary tumours and those with metastases at presentation had a particularly poor outcome. For those with a primary sarcoma, sacral location, an intralesional margin and a diameter of > 10 cm were poor prognostic indicators. Cite this article: Bone Joint J 2016;98-B:555–63.

Subglacial Lake Whillans microbial biogeochemistry: a synthesis of current knowledge

Liquid water occurs below glaciers and ice sheets globally, enabling the existence of an array of aquatic microbial ecosystems. In Antarctica, large subglacial lakes are present beneath hundreds to thousands of metres of ice, and scientific interest in exploring these environments has escalated over the past decade. After years of planning, the first team of scientists and engineers cleanly accessed and retrieved pristine samples from a West Antarctic subglacial lake ecosystem in January 2013. This paper reviews the findings to date on Subglacial Lake Whillans and presents new supporting data on the carbon and energy metabolism of resident microbes. The analysis of water and sediments from the lake revealed a diverse microbial community composed of bacteria and archaea that are close relatives of species known to use reduced N, S or Fe and CH4 as energy sources. The water chemistry of Subglacial Lake Whillans was dominated by weathering products from silicate minerals with a minor influence from seawater. Contributions to water chemistry from microbial sulfide oxidation and carbonation reactions were supported by genomic data. Collectively, these results provide unequivocal evidence that subglacial environments in this region of West Antarctica host active microbial ecosystems that participate in subglacial biogeochemical cycling.

The prognostic and therapeutic factors which influence the oncological outcome of parosteal osteosarcoma

The aim of this study was to evaluate the prognostic and therapeutic factors which influence the oncological outcome of parosteal osteosarcoma.

A total of 80 patients with a primary parosteal osteosarcoma were included in this retrospective study. There were 51 females and 29 males with a mean age of 29.9 years (11 to 78).

The mean follow-up was 11.2 years (1 to 40). Overall survival was 91.8% at five years and 87.8% at ten years. Local recurrence occurred in 14 (17.5%) patients and was associated with intralesional surgery and a large volume of tumour. On histological examination, 80% of the local recurrences were dedifferentiated high-grade tumours. A total of 12 (14.8%) patients developed pulmonary metastases, of whom half had either a dedifferentiated tumour or a local recurrence. Female gender and young age were good prognostic factors. Local recurrence was a poor prognostic factor for survival. Medullary involvement or the use of chemotherapy had no impact on survival.

The main goal in treating a parosteal osteosarcoma must be to achieve a wide surgical margin, as inadequate margins are associated with local recurrence. Local recurrence has a significant negative effect on survival, as 80% of the local recurrences are high-grade dedifferentiated tumours, and half of these patients develop metastases.

The role of chemotherapy in the treatment of parosteal osteosarcoma is not as obvious as it is in the treatment of conventional osteosarcoma. The mainstay of treatment is wide local excision.

Cite this article: Bone Joint J 2015;97-B:1698–1703.

Does total humeral endoprosthetic replacement provide reliable reconstruction with preservation of a useful extremity?

BACKGROUND

Controversy exists regarding the ideal method of reconstruction after proximal humeral resection and several reconstructive techniques have been reported. The reconstructive options are very limited when resection of the entire humerus is required. One option is endoprosthetic reconstruction, but there have been few published studies on the outcome of total humeral endoprosthetic reconstruction.

QUESTIONS/PURPOSES

The purposes of this study were (1) to assess the longevity of total humerus prostheses in those patients who survived their disease; (2) to review the complications associated with this prosthesis; and (3) to assess the Musculoskeletal Tumor Society functional score in survivors.

METHODS

Thirty-four patients (10 males, 24 females) with a mean age of 26 years (range, 7-86 years) were included in this study. Histological diagnosis was osteosarcoma in 15 patients, chondrosarcoma in seven, Ewing's sarcoma in seven, metastatic carcinoma in three, liposarcoma in one, and giant cell tumor of bone in one remaining patient. Twenty-nine patients had their total humeral endoprosthetic replacement for primary reconstruction, whereas the remaining five patients received their implants for failures with other reconstructive techniques. At a minimum followup of 3 months (mean, 8.2 years; range, 3 months to 29 years), 16 patients were alive with no evidence of disease, whereas 13 of the remaining 18 died with metastatic disease. Local recurrence was seen in five patients and all eventually died of disease progression.

RESULTS

According to the Kaplan-Meier survival analysis, the cumulative 10-year implant survival rate was 90%. Periprosthetic infection was seen in four patients, postoperative radial nerve palsy in one, and proximal migration of the prosthesis in three, whereas three patients needed a change of the articular elbow bushings at a mean of 16 years after the implant insertion. The mean Musculoskeletal Tumor Society functional score of the 28 patients who survived their disease for more than 12 months after the index procedure and could therefore be functionally assessed was 83% (range, 60%-93%).

CONCLUSIONS

From this small, preliminary report, we suggest that total humeral endoprosthetic replacement may be a reasonable option of reconstruction after tumor resection. We have shown that this prosthesis preserves the function of the hand. The local recurrence rate observed suggests that careful selection of patients is crucial. Infection was our most common surgical complication, but we showed that in those who survived their tumor, this prosthesis offers a method to preserve a functional upper extremity in some patients. Further study with more patients is necessary to confirm the value of this reconstruction method.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Ivacaftor as salvage therapy in a patient with cystic fibrosis genotype F508del/R117H/IVS8-5T

Ivacaftor is a novel CFTR potentiator that increases CFTR activity and improves clinical outcomes in cystic fibrosis (CF) patients with at least one copy of CFTR-G551D. Clinical trials have shown an improvement in lung function, weight and CF pulmonary exacerbation in adults with CFTR-G551D leading to the approval of ivacaftor as a novel CF therapy [1]. In vitro studies of ivacaftor have also shown significant improvements in CFTR chloride channel opening time in other non-G551D CFTR mutations suggesting that ivacaftor may be of benefit to patients with mutations other than gating mutations [2]. R117H-CFTR is a relatively common CFTR mutation that demonstrates an in-vitro response to ivacaftor [2,3]. A clinical trial has suggested that there may be a role for ivacaftor in older patients with R117H-CFTR although this trial did not include patients with very severe CF lung disease [4]. In 2014, ivacaftor was approved in the United States as a treatment for CF subjects aged greater than 6 years old with a copy of R117H-CFTR. We present a case demonstrating a substantial therapeutic effect of ivacaftor in a CF patient with genotype F508del/R117H and advanced lung disease.

The diagnosis of benign prostatic obstruction: Development of a clinical nomogram

AIMS

To develop a nomogram predicting benign prostatic obstruction (BPO).

METHODS

We included in this study 600 men with lower urinary tract symptoms (LUTS) and benign prostatic enlargement (BPE) who underwent standardized pressure flow studies (PFS) between 1996 and 2000. Complete clinical and urodynamic data were available for all patients. Variables assessed in univariate and multivariate logistic regression models consisted of IPSS, PSA, prostate size, maximal urinary flow rate (Qmax) at free flow, residual urine (RU), and bladder wall thickness (BWT). These were used to predict significant BPO (defined as a Schäfer grade ≥ 3 in PFS).

RESULTS

A preliminary multivariate model, including IPSS, Qmax at free flow and RU, suggested that only Qmax at free flow was a statistically significant predictor of BPO (P = 0.00) with a predictive accuracy (PA) of 82%. Further development of the multivariate model showed how the inclusion of BWT did not increase PA. Only transitional zone volume (TZV) proved to be an additional statistically significant predictor for BPO (P = 0.00). The combination of Qmax at free flow and TZV demonstrated a PA of 83.2% and were included in the final nomogram format.

CONCLUSIONS

We developed a clinical nomogram, which is both accurate and well calibrated, which can be helpful in the management of patients with LUTS and BPE. External validation is warranted to confirm our findings.

Characterisation and comparison of the uptake of ionizable and polar pesticides, pharmaceuticals and personal care products by POCIS and Chemcatchers

Growing concern about the environmental impact of ionizable and polar organic chemicals such as pesticides, pharmaceuticals and personal care products has lead to the inclusion of some in legislative and regulatory frameworks. It is expected that future monitoring requirements for these chemicals in aquatic environments will increase, along with the need for low cost monitoring and risk assessment strategies. In this study the uptake of 13 neutral and 6 ionizable pesticides, pharmaceuticals and personal care products by modified POCIS (with Strata™-X sorbent) and Chemcatchers™ (SDB-RPS or SDB-XC) was investigated under controlled conditions at pH = 6.5 for 26 days. The modified POCIS and Chemcatcher™ (SDB-RPS) samplers exhibited similar performance with the uptake of the majority of the 19 chemicals of interest categorised as linear over the 26 day deployment. Only a few ionized herbicides (picloram and dicamba) and triclosan showed negligible accumulation. Chemcatcher™ with SDB-XC sorbent performed relatively poorly with only carbamazepine having a linear accumulation profile, and 8 compounds showing no measurable accumulation. Differences in the uptake behavior of chemicals were not easily explained by their physico-chemical properties, strengthening the requirement for detailed calibration data. PES membranes accumulated significant amount of some compounds (i.e. triclosan and diuron), even after extended deployment (i.e. 26 days). At present there is no way to predict which compounds will demonstrate this behavior. Increasing membrane pore size from 0.2 to 0.45 μm for Chemcatcher™ (SBD-RPS) caused an average increase in Rs of 24%.

The utility of the ISAC allergen array in the investigation of idiopathic anaphylaxis

A diagnosis of idiopathic anaphylaxis following a detailed clinical assessment remains very challenging for patients and clinicians. Risk reduction strategies such as allergen avoidance are not possible. This study investigated whether the (ISAC) allergen array with 103 allergens would add diagnostic value in patients with idiopathic anaphylaxis. We extended the specific immunoglobulin (Ig)E testing in 110 patients with a diagnosis of idiopathic anaphylaxis from five UK specialist centres using ISAC arrays. These were divided into three groups: score I identified no new allergen sensitization beyond those known by previous assessment, score II identified new sensitizations which were not thought likely to explain the anaphylaxis and score III identified new sensitizations felt to have a high likelihood of being responsible for the anaphylaxis. A proportion (50%) of score III patients underwent clinical reassessment to substantiate the link to anaphylaxis in this group. The results show that 20% of the arrays were classified as score III with a high likelihood of identifying the cause of the anaphylaxis. A wide range of major allergens were identified, the most frequent being omega-5-gliadin and shrimp, together accounting for 45% of the previously unrecognized sensitizations. The ISAC array contributed to the diagnosis in 20% of patients with idiopathic anaphylaxis. It may offer additional information where a careful allergy history and follow-on testing have not revealed the cause of the anaphylaxis.

Is limb salvage surgery safe for bone sarcomas identified after a previous surgical procedure?

Bone sarcomas are rare cancers and orthopaedic surgeons come across them infrequently, sometimes unexpectedly during surgical procedures. We investigated the outcomes of patients who underwent a surgical procedure where sarcomas were found unexpectedly and were subsequently referred to our unit for treatment. We identified 95 patients (44 intra-lesional excisions, 35 fracture fixations, 16 joint replacements) with mean age of 48 years (11 to 83); 60% were males (n = 57). Local recurrence arose in 40% who underwent limb salvage surgery versus 12% who had an amputation. Despite achieving local control, overall survival was worse for patients treated with amputation rather than limb salvage (54% vs 75% five-year survival). Factors that negatively influenced survival were invasive primary surgery (fracture fixation, joint replacement), a delay of greater than two months until referral to our oncology service, and high-grade tumours. Survival in these circumstances depends mostly on factors that are determined prior to definitive treatment by a tertiary orthopaedic oncology unit. Limb salvage in this group of patients is associated with a higher rate of inadequate marginal surgery and, consequently, higher local recurrence rates than amputation, but should still be attempted whenever possible, as local control is not the primary determinant of survival.

Cite this article: Bone Joint J 2014;96-B:665–72.

The relationship between pretreatment anaemia and survival in patients with adult soft tissue sarcoma

INTRODUCTION

Anaemia is present in more than 30 % of patients with various cancers at the time of initial presentation. Anaemia or a lower level of haemoglobin (Hb) is an indicator of poorer prognosis in many cancers. Several studies have also demonstrated that high levels of proinflammatory cytokines contribute to the development of anaemia. However, no studies have assessed the correlation between anaemia and survival in patients with soft tissue sarcoma. The aim of this study was to elucidate the relationship between anaemia and clinical outcome and to determine whether pretreatment anaemia predicted disease-specific survival in patients with adult soft tissue sarcoma.

METHODS

A total of 376 patients between 2003 and 2010 were retrospectively reviewed. Patients who presented with metastases or/and local recurrence at diagnosis were excluded from this study.

RESULTS

Hb levels varied from 8.0 to 17.3 g/dl in all patients. Pretreatment anaemia was seen in 114 patients. Hb levels were significantly correlated to C-reactive protein levels (Spearman ρ = -0.54, p < 0.0001). The tumour histological grade, age and tumour size were also significantly correlated to Hb levels. Patients with anaemia had a worse disease-specific survival (52.6 % at 5 years) than those without anaemia (79.7 % at 5 years) (p < 0.0001). Patients with anaemia also had a worse event-free rate (44 % at 5 years) than those without anaemia (66.3 % at 5 years) (p < 0.0001). Multivariate analysis showed that anaemia remained an independent predictor of survival (p = 0.002) and events (p = 0.0003).

CONCLUSION

Pretreatment anaemia may be indicative of an aggressive characteristic in patients with soft tissue sarcoma. We recommend the routine measurement of Hb level to identify patients who are at greater risk of death or an event.

A liquid chromatography tandem mass spectrometry assay for plasma renin activity using online solid-phase extraction

Background

The plasma renin activity (PRA) assay measures the ability of renin to generate angiotensin I (AngI) from angiotensinogen. It is used to monitor mineralocorticoid therapy and to screen hypertensive individuals for primary aldosteronism (PA).

Methods

Samples were incubated in the presence of protease inhibitors for 6.5 and 24 h. The reaction was stopped by the addition of 2% ammonium hydroxide. AngI was then quantified by liquid chromatography tandem mass spectrometry using online solid-phase extraction (XLC-MS/MS).

Results

This method requires a sample volume of 50 μL and has an inter-assay precision <14% across the working range. A 6.5-h incubation gave a lower limit of quantification (LLOQ) of 0.3 nmol/L/h and this can be reduced to 0.08 nmol/L/h using a 24-h incubation. Comparison to a radioimmunoassay revealed excellent correlation ( r2 = 0.98), but a 37% negative bias. We also found that renin is stable in whole blood for up to 24 h at room temperature. In contrast, storage at 4°C should be avoided as prorenin cryoactivation can affect the PRA result in some patient groups.

Conclusions

We have developed and fully validated a semi-automated XLC-MS/MS method for the measurement of PRA. In addition, a reference range specific to this assay has been defined. We have also demonstrated that renin is stable for up to 24 h at room temperature. This will enable this assay to be extended to samples taken in primary care, potentially increasing the number of hypertensive patients who can be screened for PA.