Regorafenib in patients with relapsed advanced or metastatic chordoma: results of a non-comparative, randomised, double-blind, placebo-controlled, multicentre phase II study

BACKGROUND

REGOBONE multicohort study explored the efficacy and safety of regorafenib for patients with advanced bone sarcomas; this report details the cohort of patients with relapsed advanced or metastatic chordoma.

METHODS

Patients with relapsed chordoma progressing despite 0-2 prior lines of systemic therapy, were randomised (2 : 1) to receive regorafenib (160 mg/day, 21/28 days) or placebo. Patients on placebo could cross over to receive regorafenib after centrally-confirmed progression. The primary endpoint was the progression-free rate at 6 months (PFR-6) (by RECIST 1.1). With one-sided α of 0.05, and 80% power, at least 10/24 progression-free patients at 6 months (PFR-6) were needed for success.

RESULTS

From March 2016 to February 2020, 27 patients were enrolled. A total of 23 patients were assessable for efficacy: 7 on placebo, 16 on regorafenib, 16 were men, median age was 66 (32-85) years. At 6 months, in the regorafenib arm, 1 patient was not assessable, 6/14 were non-progressive (PFR-6: 42.9%; one-sided 95% CI = 20.6) 3/14 discontinued regorafenib due to toxicity; and in the placebo arm, 2/5 patients were non-progressive (PFR-6: 40.0%; one-sided 95% CI = 7.6), 2 were non-assessable. Median progression-free survival was 8.2 months (95% CI 4.5-12.9 months) on regorafenib and 10.1 months (95% CI 0.8 months-non evaluable [NE]) on placebo. Median overall survival rates were 28.3 months (95% CI 14.8 months-NE) on regorafenib but not reached in placebo arm. Four placebo patients crossed over to receive regorafenib after centrally-confirmed progression. The most common grade ≥3 regorafenib-related adverse events were hand-foot skin reaction (22%), hypertension (22%), pain (22%), and diarrhoea (17%), with no toxic death.

CONCLUSION

This study failed to show any signal of benefit for regorafenib in patients with advanced/metastatic recurrent chordoma.

Reduced and stable feature sets selection with random forest for neurons segmentation in histological images of macaque brain

In preclinical research, histology images are produced using powerful optical microscopes to digitize entire sections at cell scale. Quantification of stained tissue relies on machine learning driven segmentation. However, such methods require multiple additional information, or features, which are increasing the quantity of data to process. As a result, the quantity of features to deal with represents a drawback to process large series or massive histological images rapidly in a robust manner. Existing feature selection methods can reduce the amount of required information but the selected subsets lack reproducibility. We propose a novel methodology operating on high performance computing (HPC) infrastructures and aiming at finding small and stable sets of features for fast and robust segmentation of high-resolution histological images. This selection has two steps: (1) selection at features families scale (an intermediate pool of features, between spaces and individual features) and (2) feature selection performed on pre-selected features families. We show that the selected sets of features are stables for two different neuron staining. In order to test different configurations, one of these dataset is a mono-subject dataset and the other is a multi-subjects dataset to test different configurations. Furthermore, the feature selection results in a significant reduction of computation time and memory cost. This methodology will allow exhaustive histological studies at a high-resolution scale on HPC infrastructures for both preclinical and clinical research.

Protuberant fibro-osseous lesion of the temporal bone: report of four cases and review of the literature

'Bullough lesions', also referred to as protuberant fibro-osseous lesions (PFOL), are rare temporal bone lesions initially described in 1999. Since only 12 cases have been reported, several key issues, such as their origin and recommended management strategies, remain unresolved. This article reports the largest cohort included in the literature to date, comprising four patients with PFOL. PFOL appears to be characterized by female and right-side predominance. These lesions were consistently located regarding the mastoid, generally diagnosed in early adulthood, without functional symptoms, and were always fibro-osseous. Invasive/malignant features were not found on imaging or histology. The main differential diagnosis was malignant low-grade parosteal osteosarcoma. Clinical examination and computed tomography images provided strong elements supporting the diagnosis of PFOL. Biopsy allowed molecular biology investigations (MDM2 and CDK4 amplification), in order to rule out low-grade parosteal osteosarcoma.

[Therapeutic education in primary cardiovascular prevention]

BACKGROUND

As primary prevention against cardiovascular diseases, Patient Therapeutic Education helps to develop a protective lifestyle within a socioeconomic context where risk factors abound.

PATIENTS AND METHODS

Patient Therapeutic Education offers those eager to protect their cardiovascular health a program of six workshops. Upon enrolment, a Program aide conducts an educational diagnosis with the patient, specific to each workshop theme, so that he might understand the clinical, socio-professional, cognitive and psycho-affective dimensions. An evaluation of each workshop is requested from participants in the form of open and closed questions.

RESULTS

The study comprised 2225people, majority women (79%), relatively old (age 63.9for women, 66.3for men), most often retired (65%). An analysis of the educational diagnosis notes a great frequency of classic risk factors; a good knowledge of the factors favoring them contrasting with the weak means implemented in everyday life to reduce their impact; the great majority of participants (68%) believe they have a well balanced diet; patients are greatly involved in their own health, with a slight external locus involving the general practitioner, the immediate entourage and society. The notes of the evaluation are usually maximum.

CONCLUSION

Patient Therapeutic Education arouses strong interest in the public, allows a personalized approach that optimizes learning, increases knowledge and facilitates the use of new protective practices.

Prediction of local and metastatic recurrence in solitary fibrous tumor: construction of a risk calculator in a multicenter cohort from the French Sarcoma Group (FSG) database

Background

Solitary fibrous tumors (SFT) are rare unusual ubiquitous soft tissue tumors that are presumed to be of fibroblastic differentiation. At present, the challenge is to establish accurate prognostic factors.

Patients and methods

A total of 214 consecutive patients with SFT diagnosed in 24 participating cancer centers were entered into the European database (www.conticabase.org) to perform univariate and multivariate analysis for overall survival (OS), local recurrence incidence (LRI) and metastatic recurrence incidence (MRI) by taking competing risks into account. A prognostic model was constructed for LRI and MRI. Internal and external validations of the prognostic models were carried out. An individual risk calculator was carried out to quantify the risk of both local and metastatic recurrence.

Results

We restricted our analysis to 162 patients with local disease. Twenty patients (12.3%) were deceased at the time of analysis and the median OS was not reached. The LRI rates at 10 and 20 years were 19.2% and 38.6%, respectively. The MRI rates at 10 and 20 years were 31.4% and 49.8%, respectively. Multivariate analysis retained age and mitotic count tended to significance for predicting OS. The factors influencing LRI were viscera localization, radiotherapy and age. Mitotic count, tumor localization other than limb and age had independent values for MRI. Three prognostic groups for OS were defined based on the number of unfavorable prognostic factors and calculations were carried out to predict the risk of local and metastatic recurrence for individual patients.

Conclusion

LRI and MRI rates increased between 10 and 20 years so relapses were delayed, suggesting that long-term monitoring is useful. This study also shows that different prognostic SFT sub-groups could benefit from different therapeutic strategies and that use of a survival calculator could become standard practice in SFTs to individualize treatment based on the clinical situation.

Primary subacute epiphyseal osteomyelitis caused by Mycobacterium species in young children: a modern diagnostic approach

Primary epiphyseal subacute osteomyelitis (PESAO) caused by Mycobacterium species in young children is poorly recognized. We aimed to define the spectrum of this uncommon condition and to propose a novel diagnostic approach. We performed a systematic review of the literature on the PubMed website by selecting all reports of isolated infantile PESAO caused by Mycobacterium species since 1975. We identified 350 citations, of which 174 were assessed for eligibility based on title and abstract. The full text of 81 eligible citations was screened, and relevant data of 15 children under 4 years of age with mycobacterial PESAO were extracted. These data were pooled with those from our Institution. Data from 16 children were reviewed. The median age was 16 ± 7 months and the male:female ratio 1.7. The knee was the most common infection site (94%). The diagnosis of mycobacterial disease was delayed in all cases (range, 2 weeks to 6 months), and initially presumed by histology in 15 children (94%). Microbiologically proven diagnosis was confirmed by bone cultures in 8 of the 15 children (53%), and by specific PCR in 2 of the 3 culture-negative bone specimens (67%). Three children experienced long-term orthopedic complications despite surgical drainage and prolonged antimycobacterial regimens. All recently reported cases came from high-burden tuberculosis areas. Mycobacterium species contribute to the burden of infantile PESAO in endemic tuberculosis areas and may cause growth disturbances. We argue in favor of the early recognition of mycobacterial disease by specific molecular assays in children with infantile PESAO living in high-burden areas.

"Giant cell reparative tumor: An exceptional differential diagnosis for a lytic lesion of the temporal bone"

BACKGROUND AND IMPORTANCE

Giant cell reparative granuloma is a very rare benign osteolytic lesion. It typically arises in the mandible and rarely involves the skull.

CLINICAL PRESENTATION

A 25-year-old male was admitted in August 2002 for a painless left preauricular mass of several months duration. CT scan revealed an osteolytic extradural lesion located in the temporal bone, with extension to infratemporal fossa. We performed a surgical partial resection of the tumour via a frontotemporal approach. At 36 months after surgery, the lesion continued growth and subsequently we decided to perform a preauricular infratemporal approach. After a ten year-follow-up, the patient remained asymptomatic and a small tumour remnant was visible and stable.

CONCLUSION

Giant cell reparative granulomas that originate from the temporal bone are exceptional. There are no typical radiological features of this disease. Diagnosis is confirmed by analysis of the surgical specimen. Tumor growth requires surgical resection.

Linking the lytic and lysogenic bacteriophage cycles to environmental conditions, host physiology and their variability in coastal lagoons

Changes in environmental conditions and prokaryote physiology can strongly affect the dynamics of both the lysogenic and lytic bacteriophage replication cycles in aquatic systems. However, it remains unclear whether it is the nature, amplitude or frequency of these changes that alter the phage replication cycles. We performed an annual survey of three Mediterranean lagoons with contrasting levels of chlorophyll a concentration and salinity to explore how these cues and their variability influence either replication cycle. The lytic cycle was always detected and showed seasonal patterns, whereas the lysogenic cycle was often undetected and highly variable. The lytic cycle was influenced by environmental and prokaryotic physiological cues, increasing with concentrations of dissolved organic carbon, chlorophyll a, and the proportion of respiring cells, and decreasing with the proportion of damaged cells. In contrast, lysogeny was not explained by the magnitude of any environmental or physiological parameter, but increased with the amplitude of change in prokaryote physiology. Our study suggests that both cycles are regulated by distinct factors: the lytic cycle is dependent on environmental parameters and host physiology, while lysogeny is dependent on the variability of prokaryote physiology. This could lead to the contrasting patterns observed between both cycles in aquatic systems.

Value of diffusion-weighted images in differentiating mid-course responders to chemotherapy for osteosarcoma compared to the histological response: preliminary results

BACKGROUND

Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy.

OBJECTIVE

To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment.

MATERIALS AND METHODS

This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 - ADC1 and ADC3 - ADC1), and their variation (ADC2 - ADC1/ADC1 and ADC3 - ADC1/ADC1) were calculated for each of these three time points.

RESULTS

Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 - ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups.

CONCLUSION

DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy.

Phytoplankton distribution and productivity in a highly turbid, tropical coastal system (Bach Dang Estuary, Vietnam)

Phytoplankton diversity, primary and bacterial production, nutrients and metallic contaminants were measured during the wet season (July) and dry season (March) in the Bach Dang Estuary, a sub-estuary of the Red River system, Northern Vietnam. Using canonical correspondence analysis we show that phytoplankton community structure is potentially influenced by both organometallic species (Hg and Sn) and inorganic metal (Hg) concentrations. During March, dissolved methylmercury and inorganic mercury were important factors for determining phytoplankton community composition at most of the stations. In contrast, during July, low salinity phytoplankton community composition was associated with particulate methylmercury concentrations, whereas phytoplankton community composition in the higher salinity stations was more related to dissolved inorganic mercury and dissolved mono and tributyltin concentrations. These results highlight the importance of taking into account factors other than light and nutrients, such as eco-toxic heavy metals, in understanding phytoplankton diversity and activity in estuarine ecosystems.

[Morphological classification of glioblastomas]

BACKGROUND AND PURPOSE

In the 2007 WHO classification, glioblastomas are classified among the group of astrocytic tumors. They are highly malignant (grade IV). This group of tumors is morphologically heterogeneous. The WHO distinguishes between clinico-pathological entities, variants of entities and histological pattern. Variants are defined as being reliably indentified histologically and having some relevance for clinical outcome but as still being part of a previously defined overarching entity. Patterns of differentiation are identifiable by histological appearances but without clinical or pathological significance.

METHODS

The description of the histological and immunohistochemical features is based on the 2007 WHO classification.

RESULTS

In addition to the classic form of glioblastoma, two variants exist: the giant cell GBM and the gliosarcoma. The first but not the second would have a better outcome than the classic glioblastoma. The WHO classification also distinguishes several patterns of differentiation: small cells glioblastoma; glioblastoma with lipidized cells; glioblastoma with oligodendroglioma component; glioblastoma with heterologous differentiation. These patterns have to be recognized because they represent sometimes a diagnostic challenge. GFAP, Olig2 and Mib1/Ki67 are the most relevant immunohistochemical markers. Diagnostic value of neuronal markers is still controversial. EGFR or p53 expression can be detected and their prognosis value is discussed in this chapter. A systematic analysis of some markers in routine, for example IDH1 or internexin-a, could help to define more homogeneous groups of patients.