Time is myelin: early cortical myelin repair prevents atrophy and clinical progression in multiple sclerosis

Cortical myelin loss and repair in multiple sclerosis (MS) have been explored in neuropathological studies, but the impact of these processes on neurodegeneration and the irreversible clinical progression of the disease remains unknown. Here, we evaluated in vivo cortical demyelination and remyelination in a large cohort of people with all clinical phenotypes of MS followed up for 5 years using magnetization transfer imaging (MTI), a technique that has been shown to be sensitive to myelin content changes in the cortex. We investigated 140 people with MS (37 clinically isolated syndrome, 71 relapsing-MS, 32 progressive-MS), who were clinically assessed at baseline and after 5 years and, along with 84 healthy controls, underwent a 3 T-MRI protocol including MTI at baseline and after 1 year. Changes in cortical volume over the radiological follow-up were computed with a Jacobian integration method. Magnetization transfer ratio was employed to calculate for each patient an index of cortical demyelination at baseline and of dynamic cortical demyelination and remyelination over the follow-up period. The three indices of cortical myelin content change were heterogeneous across patients but did not significantly differ across clinical phenotypes or treatment groups. Cortical remyelination, which tended to fail in the regions closer to CSF (-11%, P < 0.001), was extensive in half of the cohort and occurred independently of age, disease duration and clinical phenotype. Higher indices of cortical dynamic demyelination (β = 0.23, P = 0.024) and lower indices of cortical remyelination (β = -0.18, P = 0.03) were significantly associated with greater cortical atrophy after 1 year, independently of age and MS phenotype. While the extent of cortical demyelination predicted a higher probability of clinical progression after 5 years in the entire cohort [odds ratio (OR) = 1.2; P = 0.043], the impact of cortical remyelination in reducing the risk of accumulating clinical disability after 5 years was significant only in the subgroup of patients with shorter disease duration and limited extent of demyelination in cortical regions (OR = 0.86, P = 0.015, area under the curve = 0.93). In this subgroup, a 30% increase in cortical remyelination nearly halved the risk of clinical progression at 5 years, independently of clinical relapses. Overall, our results highlight the critical role of cortical myelin dynamics in the cascade of events leading to neurodegeneration and to the subsequent accumulation of irreversible disability in MS. Our findings suggest that early-stage myelin repair compensating for cortical myelin loss has the potential to prevent neuro-axonal loss and its long-term irreversible clinical consequences in people with MS.

Positron emission tomography with [18 F]-DPA-714 unveils a smoldering component in most multiple sclerosis lesions which drives disease progression

OBJECTIVE

To determine the prognostic value of persisting neuroinflammation in multiple sclerosis (MS) lesions, we developed a 18kDa-translocator-protein-PET based classification of each lesion according to innate immune cell content and localization, and assessed the respective predictive value of lesion phenotype and diffuse inflammation on atrophy and disability progression over 2 years.

METHODS

Thirty-six people with MS (PwMS, disease duration 9±6y; 12 relapsing-remitting, 13 secondary -progressive, 11 primary-progressive) and 19 healthy controls (HC) underwent a dynamic [¹⁸ F]-DPA-714-PET. At baseline and after 2 years, patients also underwent MRI and neurological examination. Based on a threshold of significant inflammation defined by a comparison of [¹⁸ F]-DPA-714 binding between PwMS and HC, white matter lesions were classified as homogeneously-active (active center), rim-active (inactive center and active periphery) or non-active. Longitudinal cortical atrophy was measured using Jacobian integration.

RESULTS

PwMS had higher innate inflammation in normal appearing white matter (NAWM) and cortex than HC (respective standardized effect size: 1.15, 0.89, p: 0.003 and <0.001). Out of 1335 non-gadolinium-enhancing lesions, 53% were classified homogeneously-active (median:17/PwMS), 6% rim-active (1/PwMS) and 41% non-active (14/PwMS). The number of homogenously-active lesions was the strongest to predict longitudinal changes, associating with cortical atrophy (β =0.49, p=0.023) and Expanded Disability Status Scale changes (β=0.35, p=0.023) over 2 years. NAWM and cortical binding were not associated to volumetric and clinical changes.

INTERPRETATION

[¹⁸ F]-DPA-714-PET revealed that an unexpectedly high proportion of MS lesions have a smoldering component, which predicts atrophy and clinical progression. This suggests that following the acute phase, most lesions develop a chronic inflammatory component, promoting neurodegeneration and clinical progression. This article is protected by copyright. All rights reserved.

Periventricular remyelination failure in multiple sclerosis: a substrate for neurodegeneration

In multiple sclerosis, spontaneous remyelination is generally incomplete and heterogeneous across patients. A high heterogeneity in remyelination may also exist across lesions within the same individual, suggesting the presence of local factors interfering with myelin regeneration. In this study we explored in vivo the regional distribution of myelin repair and investigated its relationship with neurodegeneration. We first took advantage of the myelin binding property of the amyloid radiotracer 11C-PiB to conduct a longitudinal 11C-PiB PET study in an original cohort of 19 participants with a relapsing-remitting form of multiple sclerosis, followed-up over a period of 1-4 months. We then replicated our results on an independent cohort of 40 people with multiple sclerosis followed-up over 1 year with magnetization transfer imaging, an MRI metrics sensitive to myelin content. For each imaging method, voxel-wise maps of myelin content changes were generated according to modality-specific thresholds. We demonstrated a selective failure of remyelination in periventricular white matter lesions of people with multiple sclerosis in both cohorts. In both the original and the replication cohort, we estimated that the probability of demyelinated voxels to remyelinate over the follow-up increased significantly as a function of the distance from ventricular CSF. Enlarged choroid plexus, a recently discovered biomarker linked to neuroinflammation, was found to be associated with the periventricular failure of remyelination in the two cohorts (r = -0.79, P = 0.0018; r = -0.40, P = 0.045, respectively), suggesting a role of the brain-CSF barrier in affecting myelin repair in surrounding tissues. In both cohorts, the failure of remyelination in periventricular white matter lesions was associated with lower thalamic volume (r = 0.86, P < 0.0001; r = 0.33; P = 0.069, respectively), an imaging marker of neurodegeneration. Interestingly, we also showed an association between the periventricular failure of remyelination and regional cortical atrophy that was mediated by the number of cortex-derived tracts passing through periventricular white matter lesions, especially in patients at the relapsing-remitting stage. Our findings demonstrate that lesion proximity to ventricles is associated with a failure of myelin repair and support the hypothesis that a selective periventricular remyelination failure in combination with the large number of tracts connecting periventricular lesions with cortical areas is a key mechanism contributing to cortical damage in multiple sclerosis.

Imaging Characteristics of Choroid Plexuses in Presymptomatic Multiple Sclerosis: A Retrospective Study

Background and Objectives

Recent imaging studies have suggested a possible involvement of the choroid plexus (CP) in multiple sclerosis (MS). Here, we investigated whether CP changes are already detectable at the earliest stage of MS, preceding symptom onset.

Methods

This study is a retrospective analysis of 27 patients with presymptomatic MS, 97 patients with clinically definite MS (CDMS), and 53 healthy controls (HCs) who underwent a cross-sectional 3T-MRI acquisition; of which, 22 MS, 19 HCs, and 1 presymptomatic MS (evaluated 8 months before conversion to CDMS) also underwent translocator protein (TSPO) ¹⁸F-DPA-714 PET and were included in the analysis. CPs were manually segmented on 3D T1-weighted images for volumetric analysis. CP ¹⁸F-DPA-714 uptake, reflecting inflammation, was calculated as the average standardized uptake value (SUV). Multivariable regressions adjusted for age, sex, and ventricular and brain volume were fitted to test CP volume differences between presymptomatic patients and MS or HCs. For the presymptomatic case who also had ¹⁸F-DPA-714 PET, CP SUV differences with MS and HCs were assessed through Crawford-Howell tests. To provide further insight into the interpretation of ¹⁸F-DPA-714-PET uptake at the CP level, a postmortem analysis of CPs in MS vs HCs was performed to characterize the cellular localization of TSPO expression.

Results

Compared with HCs, patients with presymptomatic MS had 32% larger CPs (β = 0.38, p = 0.001), which were not dissimilar to MS CPs (p = 0.69). Moreover, in the baseline scan of the presymptomatic case who later on developed MS, TSPO PET showed 33% greater CP inflammation vs HCs (p = 0.04), although no differences in ¹⁸F-DPA-714 uptake were found in parenchymal regions vs controls. CP postmortem analysis identified a population of CD163⁺ mononuclear phagocytes expressing TSPO in MS, possibly contributing to the increased ¹⁸F-DPA-714 uptake.

Discussion

We identified an imaging signature in CPs at the presymptomatic MS stage using MRI; in addition, we found an increased CP inflammation with PET in a single presymptomatic patient. These findings suggest a role of CP imaging as an early biomarker and argue for the involvement of the blood-CSF barrier dysfunction in disease development.

Trial Registration Information

APHP-20210727144630, EudraCT-Number: 2008-004174-40; ClinicalTrials.gov: NCT02305264, NCT01651520, and NCT02319382.

Clinically relevant profiles of myelin content changes in patients with multiple sclerosis: A multimodal and multicompartment imaging study

OBJECTIVE

To investigate the clinical relevance of individual profiles of cortical and white matter lesion myelin content changes combining magnetisation transfer imaging (MTI) and 11C-PiB-positron emission tomography (PET) in patients with multiple sclerosis (MS).

METHODS

MTI and [¹¹C]PiB-PET acquired in 19 patients with MS followed up over 2-4 months and in seven healthy controls (HCs), were employed to generate individual maps of cortical and white matter (WM) lesion myelin content changes, respectively. These maps were used to calculate individual indices of demyelination and remyelination, and to investigate their association with clinical scores.

RESULTS

Cortical remyelination ranged between 1% and 5% of the total cortical volume (17%-45% of the cortical volume demyelinated at baseline). WM lesion remyelination ranged between 8% and 22% of the lesional volume. An extensive cortical remyelination was associated with a shorter disease duration (rho = -0.63, p = 0.01) and, in combination with WM lesion remyelination, explained 68%-70% of the variance of clinical scores (p < 0.01).

CONCLUSION

Our multimodal and multicompartment approach allows us to explore single-patient cortical and WM lesion demyelination and remyelination, and to generate clinically relevant indices of myelin repair. These indices may be used as outcome measures in clinical trials, thus increasing the chance to identify successful promyelinating treatments in patients with MS.

Social Profiloplasty:A Practical Assessment and Injection Guide

The trend of aesthetic medical procedures continues growing every year since decades all over the globe, especially considering minimal invasive treatments since the results are immediate and the downtime minimal. Hence, treatments with hyaluronic acid fillers have become extremely popular and routinely used in common practice. However, numerous areas of treatment were identified and described in the last years clinical training and consciousness of possibly complication remain still under represented. In the following article, we present four key treatment areas for optimal overall facial rejuvenation of what the authors define the social profile. Of each area an assessment, anatomical considerations, danger zones and the preferred personal technique of the authors are described.

Pneumomediastinum, pneumothorax and subcutaneous emphysema after tracheostomy closure. When less is more

Pneumomediastinum is a threatening complication that might occur after tight surgical closure of tracheostomy is performed. Physiopathology of this condition is based on several factors, including direct trauma to the tracheal wall caused by surgical maneuvers or insufficient closure of soft tissue layers which do not seal air leakage. In this paper we explore this phenomenon by reporting the case of one patient undergoing surgical closure of tracheostomy after two weeks, who later developed subcutaneous emphysema followed by pneumomediastinum. Physiopatology is analyzed and management strategies for this condition are suggested based on our experience.

Nonsurgical Redefinition of the Chin and Jawline of Younger Adults With a Hyaluronic Acid Filler: Results Evaluated With a Grid System Approach

BACKGROUND

Aesthetic treatment of the lower face is increasingly in demand, particularly owing to age-related changes in appearance. VYC-25L is a novel hyaluronic acid filler with high G' and high cohesivity, specifically designed for sculpting and contouring of the chin and jaw.

OBJECTIVES

The aim of this study was to assess the use of a grid traced onto the chin and jaw for guiding treatment with VYC-25L.

METHODS

This was a retrospective, single-center analysis of data from adult patients undergoing treatment of the lower third of the face with VYC-25L. A grid system of horizontal and vertical lines was used to systematize the process of treatment planning and performance.

RESULTS

Thirty subjects were enrolled (53.3% female; mean [standard deviation] age, 34.4 [2.8] years). The mean quantity of VYC-25L used was 4.0 [0.8] mL. Based on the 5-point Global Aesthetic Improvement Scale, 29 patients (96.7%) rated their appearance at 20 days posttreatment as "much improved" or "very much improved." The only complications recorded were early transient soft-tissue edema (n = 14; 46.7%) and bruising (n = 6; 20.0%). There were no cases of infection, paresthesia, asymmetry, hematoma, necrosis, or skin discoloration.

CONCLUSIONS

Treatment of the chin and jawline with VYC-25L, with injection locations determined by a standardized grid-based approach, appears to be effective and safe with high rates of patient satisfaction. Injection of this filler offers a potentially high-impact approach for patients across a variety of biological and economic circumstances.

LEVEL OF EVIDENCE: 4

Hyperdiluted calcium hydroxylapatite for the treatment of skin laxity of the neck

Despite being a common concern, there are very few minimally invasive treatments targeting neck skin laxity (NSL) reported in the literature. To assess the efficacy of hyperdiluted calcium hydroxyapatite (hy-CaHA) for the treatment of NSL, according to the NSL scale, and to estimate safety. Twenty patients showing NSL were treated with hy-CaHA 1:2. To evaluate the efficacy of hy-CaHA treatment for NSL, pictures of treated subjects were collected before and 3 months after treatment and graded according to the NSL scale, and T-student's test was applied to estimate differences. Hy-CaHA for the neck was effective according to the previously unreported NSL scale (p < 0.001) and safe. There were no major adverse events reported. This study supports the efficacy (according to the NSL scale) and safety of hy-CaHA (1:2) for NSL. Our results also highlight the utility of the newly developed NSL scale, being a useful tool to evaluate the level of NSL before treatment and to measure the outcome.

Temporomandibular Joint Arthrocentesis and Microfragmented Adipose Tissue Injection for the Treatment of Internal Derangement and Osteoarthritis: A Randomized Clinical Trial

PURPOSE

Internal derangement and osteoarthritis are the most common degenerative temporomandibular joint diseases and initial treatment for such conditions relies on arthrocentesis. Microfragmentation of adipose tissue has been proven in orthopedic literature to represent a more effective method to preserve stem cells, but no application has ever been reported in the temporomandibular joint. The purpose of this randomized clinical trial is to compare standard treatment conducted by injecting hyaluronic acid after the procedure to the new treatment relying upon microfragmented adipose tissue injection using the Lipogems technology.

MATERIALS AND METHODS

A randomized clinical trial was designed enrolling 20 patients in the control group receiving the standard treatment and 20 patients in the experimental group receiving microfragmented adipose tissue obtained through the Lipogems technology after arthrocentesis. Two main outcomes were defined, pain (visual analogic scale) and function (maximum interincisal opening). Both were measured in the immediate preoperative time, and 10 days, 1 month, and 6 months after the procedure.

RESULTS

In both groups, pain reduction and mouth opening significantly improved compared with the preoperative situation (P = .001). At 6-month follow-up, there was an almost statistically significant reduction of pain compared with preoperative visual analogic scale (P = .0546) and a statistically significant improvement of mouth opening (P = .0327). Overall, statistical analyses showed that the experimental group had a statistically significant superiority in the success rate of the procedure compared with the control group (P = .018).

CONCLUSIONS

Preliminary results of this clinical trial show that the injection of microfragmented adipose tissue can significantly improve outcomes of pain and function compared with the standard treatment and encourage to pursue research on this topic. Further studies with a longer follow-up time are needed to evaluate the clinical stability of the achieved improvement in pain and function.

Early red nucleus atrophy in relapse-onset multiple sclerosis

No study has investigated red nucleus (RN) atrophy in multiple sclerosis (MS) despite cerebellum and its connections are elective sites of MS‐related pathology. In this study, we explore RN atrophy in early MS phases and its association with cerebellar damage (focal lesions and atrophy) and physical disability. Thirty‐seven relapse‐onset MS (RMS) patients having mean age of 35.6 ± 8.5 (18–56) years and mean disease duration of 1.1 ± 1.5 (0–5) years, and 36 age‐ and sex‐matched healthy controls (HC) were studied. Cerebellar and RN lesions and volumes were analyzed on 3 T‐MRI images. RMS did not differ from HC in cerebellar lobe volumes but significantly differed in both right (107.84 ± 13.95 mm³ vs. 99.37 ± 11.53 mm³, p = .019) and left (109.71 ± 14.94 mm³ vs. 100.47 ± 15.78 mm³, p = .020) RN volumes. Cerebellar white matter lesion volume (WMLV) inversely correlated with both right and left RN volumes (r = −.333, p = .004 and r = −.298, p = .010, respectively), while no correlation was detected between RN volumes and mean cortical thickness, cerebellar gray matter lesion volume, and supratentorial WMLV (right RN: r = −.147, p = .216; left RN: r = −.153, p = .196). Right, but not left, RN volume inversely correlated with midbrain WMLV (r = −.310, p = .008), while no correlation was observed between whole brainstem WMLV and either RN volumes (right RN: r = −.164, p = .164; left RN: r = −.64, p = .588). Finally, left RN volume correlated with vermis VIIb (r = .297, p = .011) and right interposed nucleus (r = .249, p = .034) volumes. We observed RN atrophy in early RMS, likely resulting from anterograde axonal degeneration starting in cerebellar and midbrain WML. RN atrophy seems a promising marker of neurodegeneration and/or cerebellar damage in RMS.

All-in-one surgical guide: A new method for cranial vault resection and reconstruction

INTRODUCTION

Great precision is required for craniofacial surgery, and computer-aided design (CAD) methods may be used to plan surgery before it is performed. In this study, three-dimensional (3D)-printed cutting guides are used to match computer models with surgical procedures. We describe a novel method of computer-aided surgery for autologous cranioplasty that includes a new strategy for generating and using cutting guides. These guides may be used not only for osteotomies, but also for many other steps in the surgical procedure.

MATERIALS AND METHODS

Preoperatively, anatomical data were imported into a CAD package and used for virtual surgical planning (VSP). Cutting guides were designed after considering how to integrate all the surgical steps. Models of the microplates and micro-screws were also made. Surgical guides were exported and printed, and preoperative simulations using a replica of the patient's skull established the sequence of steps. The accuracy of the procedure was evaluated postoperatively using computed tomography (CT) scans.

RESULTS

In every patient examined, the all-in-one surgical-guide system was able to automate the many steps in the procedure and dramatically decreased the duration of surgery. The experimental guide enhanced every phase of surgery, including excising the lesion, and harvesting, positioning, and fixing the graft. In each step, precision was enhanced and the outcome corresponded with the VSP.

CONCLUSIONS

The few previous reports on cutting guides used in cranioplasty generally describe the use of separate guides for dismantling and reconstruction. The ability to perform more surgical sequences using a single tool can improve surgical accuracy. Clearly there is no single perfect surgical guide; however, effective surgical-design strategies should be used to build the best approach to each procedure.

Enlarged Virchow Robin spaces associate with cognitive decline in multiple sclerosis

The clinical significance of Virchow Robin spaces (VRS) in inflammatory brain disorders, especially in multiple sclerosis (MS), is still undefined. We analysed enlarged VRS (eVRS) by means of phase sensitive inversion recovery (PSIR) MRI sequence and investigated their association with inflammation or brain atrophy, and to clinical or physical disability. Forty-three MS patients (21 clinically isolated syndrome suggestive of MS [CIS], 15 RRMS, 7 progressive [PMS]) and 10 healthy controls (HC) were studied. 3DT1, 3DFLAIR and 2DPSIR images were obtained with a 3T MRI scanner. eVRS number and volume were calculated by manual segmentation (ITK-SNAP). Freesurfer was used to assess brain parenchymal fraction (BPF). All patients underwent clinical (EDSS) and cognitive (Rao’s BRB and DKEFS) evaluation.

eVRS number and volume resulted significantly higher on 2D-PSIR compared to both 3D-T1 (p<0.001) and 3D-FLAIR (p<0.001) and were significantly increased in CIS compared to HC (p<0.05), in PMS and RRMS compared to CIS (p<0.001) and in male versus female patients (p<0.05). eVRS volume increased significantly with disease duration (r = 0.6) but did not correlate with EDSS. eVRS significantly correlated with SPARTd (r = -0.47) and DKEFSfs (r = -0.46), especially when RRMS and PMS were merged in a single group (r = 0.89, p = 0.002 and r = 0.66, p = 0.009 respectively), while no correlation was found with BPF (r = 0.3), gadolinium-enhancing lesions (r = 0.2) and WMT2 lesion volume (r = 0.2). 2DPSIR allowed the detection of an impressive higher number of eVRS compared to 3DT1 and 3DFLAIR. eVRS associate with SPARTd and DKEFSfs failure in relapse-onset MS, suggesting they may contribute to cognitive decline in MS.

MRI-detectable cortical lesions in the cerebellum and their clinical relevance in multiple sclerosis

BACKGROUND

The demonstration of cortical lesions (CL) in the cerebellum by magnetic resonance imaging (MRI) is hampered by technical and anatomical constraints.

OBJECTIVE

To investigate the occurrence of cerebellar CL and their correlation with cerebellar-related disability by combining Double Inversion Recovery (DIR) and Phase Sensitive Inversion Recovery (PSIR) MRI images in multiple sclerosis (MS) patients.

MATERIAL AND METHODS

40 MS patients (10 CIS/eRRMS, 24 RRMS, 6 SPMS), having a wide range of disability and disease duration, were enrolled. DIR and PSIR images were obtained with a 3T-MRI.

RESULTS

Cerebellar white matter lesions (WML) and/or CL were observed in 33/40 patients (82.5%) among which 14/40 had only CL. CL were demonstrated in 26/40 patients by DIR and in 31/40 by PSIR, and their number increased from CIS/eRRMS to SPMS. PSIR disclosed a significantly higher number of CL compared to DIR (RRMS: p=0.0008; SPMS: p=0.002). CL number correlates with the cerebellar Expanded Disability Status Score (EDSS) score (r=0.72, p<0.0001). No correlation was observed between supra-tentorial and cerebellar CL.

CONCLUSIONS

CL are detected by PSIR in the cerebellum of the majority of MS patients, are more than WML, increase with disease progression and strongly correlate with the cerebellar EDSS. Thus, the observation of CL in the cerebellum of MS at clinical onset might be useful for prognostic and therapeutic aims.

The Parallel Analysis of Phase Sensitive Inversion Recovery (PSIR) and Double Inversion Recovery (DIR) Images Significantly Improves the Detection of Cortical Lesions in Multiple Sclerosis (MS) since Clinical Onset

BACKGROUND

Double inversion recovery (DIR) detects only a minority (<20%) of cortical lesions (CL) in multiple sclerosis (MS). Phase-sensitive inversion recovery (PSIR) was suggested to be substantially superior to DIR in the detection of cortical lesions (CL). These two sequences might be complementary.

OBJECTIVES

To analyze CL frequency and type in MS patients having different disease duration and disability, including patients at clinical onset, and to discern more correctly the artifacts, by combining DIR and PSIR images.

PATIENTS AND METHODS

40 patients were enrolled in the study: 10 clinically isolated syndrome/early relapsing remitting MS (CIS/eRRMS), 24 relapsing remitting MS (RRMS), 6 secondary progressive MS (SPMS). DIR and PSIR images were jointly used to classify lesions as purely intracortical (IC), leukocortical (LC) and juxtacortical (JC).

RESULTS

PSIR disclosed CL in 100% of the patients and was capable of identifying more than four times lesions (455.5%, p<0.00001), especially IC (mean numbers: 36.5 in CIS/eRRMS, 45.0 in RRMS and 52.3 in SPMS) and LC (mean numbers: 10.9 in CIS/eRRMS, 20.1 in RRMS and 25.3 in SPMS), compared to DIR (p<0.00001). CL number was significantly higher in SPMS compared to RRMS (p<0.0001). Artifacts were more accurately identified by comparing the two sequences.

CONCLUSIONS

Our study confirms the higher ability of PSIR in disclosing and classifying CL. The presence of CL in all CIS patients further points out the relevance of cortical pathology in MS. Whether the parallel analysis of DIR and PSIR images may be useful for diagnostic purposes, especially when a diagnosis of MS is suspected but not confirmed by routine MRI, needs to be evaluated in larger patient series. The analysis of the cortex by DIR and PSIR may also allow a better stratification of the patients for prognostic and counseling purposes, as well as for their inclusion in clinical studies.

Incidence of pleural mesothelioma in Liguria Region, Italy (1996–2002)

In this study, incidence of pleural malignant mesothelioma (PMM) in the Liguria Region (Italy) (approximately 1.6 million inhabitants), in the presence of asbestos exposure was investigated. New PMM cases recorded by the Mesothelioma Registry of Liguria, from 1996 to 2002 and interviews reported on a standardised questionnaire were analysed according to demographical and etiological characteristics. Nine hundred and forty five PMM cases were recorded (757 males and 188 females); the age standardised (European population) incidence rates per 100,000 were 8.51 and 1.43, respectively. The rates among the four provinces ranged between 1.18 and 13.7 for males and 0.68 and 1.44 for females. The questionnaire was evaluated for 786 PMM cases (or next-of-kin). Higher incidence rates were reported in the provinces with larger industrial and harbour areas, including shipyards (construction and repair), dockyards, building activities, chemical and heavy industrial activities. Asbestos exposure was unlikely or unknown for 57.5% females and 15% males. A major role of environmental asbestos exposure in the etiology of PMM is hypothesised for females and for a minor proportion of males.

[Occupational exposure to asbestos and recognition of pleural mesothelioma as occupational disease in the province of Genoa]

The present study compares the data of pleural mesothelioma (PM) patients resident in the province of Genoa (Italy) who, in the period 1994-1996, applied to the Italian National Insurance Institute for Work Accident (INAIL), for workers' compensation for asbestos-related diseases due to occupational exposure, with the dataset of PM patients collected by the Mesothelioma Registry of Liguria (REM) in the same period and in the same area. As PM is a malignant tumor of a prevalently occupational origin, it is recognized and acknowledged as such by INAIL when clinical and etiological characteristics are matched. Objectives of this study were to describe observed PM cases, to evaluate completeness of collected data and differences between those who requested compensation and those who did not. The REM describes the incidence of PM among Ligurian residents, proposing patients with a specific questionnaire to assess occupational, environmental and indoor asbestos exposures. The REM collected 199 new cases of PM among the residents of both the city of Genoa (1994-96) and the province of Genoa (1995-96). In the same period, INAIL received 48 (24%) applications for compensation. Among these, 43 subjects were included in a subgroup of 98 patients registered in the REM as cases with definite diagnosis and ascertained asbestos exposure; 32 were awarded compensation, while 11 are under evaluation. The data collected by REM do not show proven asbestos exposure and/or PM diagnosis for five other subjects (two compensated and three under judgment). This study reveals that: a) only a 24% of the patients with a diagnosis of PM and asbestos exposure apply for compensation; b) an exchange of information among institutions involved in primary prevention, in the evaluation of occupational exposures to carcinogens and in insurance compensation is useful.

[Mesothelioma registry of the Liguria region. Incidence and occupational etiology in a high risk area]

This paper presents the epidemiological analyses based on the first 5 years of activity of the Mesothelioma Registry of Liguria (REM). REM is a population-based cancer registry specialized in the study of both the incidence and etiology of primary pleural and peritoneal mesothelioma in Liguria (Italy). The REM completes normal clinical information with occupational and environmental anamnestic data in order to identify working and living areas at risk for asbestos-related pathologies. The REM started its activity in 1994 describing the incidence of pleural mesothelioma (PM) exclusively in the population resident in the city of Genoa (660,000 inhabitants); since 1996 the REM has studied the entire Liguria Region (1,640,000 inhabitants), where nearly 120 new cases of PM are diagnosed annually (20% are women). In the city of Genoa, between 1986-1987 and 1997-1998, PM crude incidence rate rose from 13.8 to 26.7 per 100,000 males over 40 years old. From 1994 to 1998 the REM registered 495 new patients with histologically (62%) and cytologically (9%) confirmed diagnosis of PM. 54% of them were immunocytohistochemically evaluated. Occupational information has been gathered for 248 subjects, i.e., 61% of cases with sure or probable diagnosis of PM. For 126 patients, occupational asbestos exposure (direct, indirect or only presence in the workplace) was identified on average 40 years before diagnosis. In particular, asbestos exposure was documented in shipyards, docks and cargo handling settings, building trades, iron and steel industries. Interestingly, during the same period (1955-1960), a large fraction of subjects without proved or declared direct asbestos exposure claimed to have worked in the same occupational settings. This suggests a possible unconscious indirect exposure to asbestos fibers in the workplace.