Validation of skeletal muscle mass assessment at the level of the third cervical vertebra in patients with head and neck cancer

BACKGROUND

Low skeletal muscle mass (SMM) is associated with adverse outcomes. SMM is often assessed at the third lumbar vertebra (L3) on abdominal imaging. Abdominal imaging is not routinely performed in patients with head and neck cancer (HNC). We aim to validate SMM measurement at the level of the third cervical vertebra (C3) on head and neck imaging.

MATERIAL AND METHODS

Patients with pre-treatment whole-body computed tomography (CT) between 2010 and 2018 were included. Cross-sectional muscle area (CSMA) was manually delineated at the level of C3 and L3. Correlation coefficients and intraclass correlation coefficients (ICCs) were calculated. Cohen's kappa was used to assess the reliability of identifying a patient with low SMM.

RESULTS

Two hundred patients were included. Correlation between CSMA at the level of C3 and L3 was good (r = 0.75, p < 0.01). Using a multivariate formula to estimate CSMA at L3, including gender, age, and weight, correlation improved (r = 0.82, p < 0.01). The agreement between estimated and actual CSMA at L3 was good (ICC 0.78, p < 0.01). There was moderate agreement in the identification of patients with low SMM based on the estimated lumbar skeletal muscle mass index (LSMI) and actual LSMI (Cohen's κ: 0.57, 95%CI 0.45-0.69).

CONCLUSIONS

CSMA at C3 correlates well with CSMA at L3. There is moderate agreement in the identification of patients with low SMM based on the estimated lumbar SMI (based on measurement at C3) and actual LSMI.

Skeletal muscle mass is an imaging biomarker for decreased survival in patients with oropharyngeal squamous cell carcinoma

OBJECTIVES

Low skeletal muscle mass (SMM) and sarcopenic obesity (co-presence of low SMM and obesity) are emerging prognosticators in oncology, but the prevalence and prognostic value in oropharyngeal squamous cell carcinoma (OPSCC) is not yet known.

MATERIALS AND METHODS

Patients with OPSCC, curative treatment intention and pre-treatment diagnostic imaging of the head and neck area were included. Patients with unknown HPV-status, palliative treatment intention or unavailable imaging were excluded, Relevant demographic and clinical characteristics were collected between 2009 and 2016. Patients were stratified into a low-, intermediate-, and high-risk group according to HPV-status, amount of pack-years, tumor and nodal stage. SMM was radiologically measured and cutoff values were determined by optimal stratification. The prognostic value of low SMM and sarcopenic obesity for overall survival (OS) and disease-free survival (DFS) was determined by Cox regression analysis and Kaplan Meier survival curves.

RESULTS

In 216 patients, low SMM and sarcopenic obesity were present in 140 (64.8%) and 13 (6.0%) patients, respectively. On multivariate analysis, stratification into a high-risk group (HPV-negative status with ≥10-pack-years or T4-stage) was a prognostic factor for OS and DFS (HR 2.93, p < 0.01) (HR 4.66, p < 0.01). Of specific interest, sarcopenic obesity was a strong negative prognostic factor for OS and DFS (HR 4.42, p < 0.01 and (HR 3.90, p < 0.05), independent from other well-known prognostic factors such as HPV-status.

CONCLUSION

Low skeletal muscle mass is highly prevalent in OPSCC patients. Sarcopenic obesity is a novel pretreatment prognosticator for OS and DFS in OPSCC and should therefore be considered in clinical decision making.

Interobserver agreement of skeletal muscle mass measurement on head and neck CT imaging at the level of the third cervical vertebra

OBJECTIVES

Skeletal muscle mass (SMM) is most often assessed in cancer patients on abdominal computed tomography (CT) imaging at the level of the third lumbar vertebra (L3). Abdominal CT imaging is not routinely performed in head and neck cancer (HNC) patients. Recently, a novel method to assess SMM on a single transversal CT slice at the level of the third cervical vertebra (C3) was published. The objective of this study was to assess the robustness of this novel C3 measurement method in terms of interobserver agreement.

PATIENTS AND METHODS

Patients diagnosed with locally advanced head and neck squamous cell carcinoma (LA-HNSCC) at our center between 2007 and 2011 were evaluated. Fifty-four patients with were randomly selected for analysis. Six observers independently measured the cross-sectional muscle area (CSMA) at the level of C3 using a predefined, written protocol as instruction. Interobserver agreement was assessed using intraclass correlation coefficients (ICCs), a Bland-Altman plot and Fleiss' kappa (κ).

RESULTS

The agreement in vertebra selection between all observers was excellent (Fleiss' κ: 0.96). There was a substantial agreement between all observers in single slice selection (Fleiss' κ: 0.61). For all CSMA measurements, ICCs were excellent (0.763-0.969; all p < 0.001). The Bland-Altman plot showed good agreement between measurements, with narrow limits of agreement.

CONCLUSION

Interobserver agreement for SMM measurement at the level of C3 was excellent. Assessment of SMM at the level of C3 is easy and robust and can performed on routinely available imaging in HNC patients.

Systematic review of the diagnostic value of laryngeal stroboscopy in excluding early glottic carcinoma

OBJECTIVE

Laryngeal stroboscopy is an important diagnostic tool in the work-up of patients with phoniatric complaints. The aim of this article was to evaluate the diagnostic value of laryngeal stroboscopy in excluding glottic carcinoma in patients with suspected glottic carcinoma.

DATA SOURCES

PubMed, Embase and the Cochrane Library.

REVIEW METHODS

A systematic literature search was performed in PubMed, Embase and the Cochrane Library. Studies reporting original study data were included. Studies were selected based on predefined inclusion and exclusion criteria and were consequently systematically assessed for their relevance and risk of bias. Studies with low relevance, high risk of bias or both were excluded from analysis. The prevalences, sensitivities, specificities and post-test probabilities of laryngeal stroboscopy for detecting glottic carcinoma were extracted or calculated with data supplied in the articles.

RESULTS

Seven studies, with high relevance and moderate risk of bias, were selected for data extraction. The baseline risk of glottic carcinoma was 25-49% in the included studies. Sensitivity ranged between 80% and 100% and specificity between 25% and 100%. Post-test probabilities of malignancy in case of an abnormal stroboscopy ranged between 35% and 100%. Post-test probabilities of malignancy in case of a normal stroboscopy ranged between 0% and 29%.

CONCLUSION

A normal laryngeal stroboscopic result predicts the absence of invasive carcinoma. Laryngeal stroboscopy can therefore be suggested as a useful supplemental examination in the standard diagnostic work-up for all patients with suspected glottic carcinoma.

Effect of oral contraceptives on lamotrigine levels depends on comedication

OBJECTIVES

To evaluate prospectively the influence of cyclic oral contraceptive (OC) use on lamotrigine (LTG) serum levels when used in combination therapy.

METHODS

Women with epilepsy using LTG in combination with valproate (VPA; n=7), carbamazepine (CBZ; n=3) or oxcarbazepine (OXC; n=1) were evaluated during two periods of 28 days cyclic OC use, monitoring antiepileptic drug (AED) levels every other day with the dried blood spot sampling method. Results were compared with women on LTG monotherapy and OCs (n=12). Pharmacokinetic analysis was performed using NONMEM software.

RESULTS

Mean study population value of LTG clearance estimated by the final model was 3.17 l/h. Introduction of covariates for comedication (VPA, CBZ, OXC and OC) significantly reduced the between-subject variability. A significant influence of OC comedication on LTG clearance was seen in both LTG monotherapy (clearance with OC 4.02±0.38 l/h, OC-free week 3.03±0.39 l/h) and in LTG-CBZ combination (clearance with OC 4.95±0.15 l/h, OC-free week 4.15±0.26 l/h). No influence of OC was found in LTG-VPA combination (clearance with OC 0.99±0.16 l/h, OC-free week 0.90±0.15 l/h).

CONCLUSIONS

Adding OCs to LTG monotherapy or the combination LTG-CBZ significantly increased the LTG clearance and thus reduced LTG serum levels. In the combination LTG-CBZ, OCs had a non-significant effect on CBZ clearance. No significant influence of cyclic OC use on LTG or VPA clearance was found when these AEDs were used in combination.

Magnetic tracking in the operation room using the da Vinci(®) telemanipulator is feasible

In recent years, robotic assistance for surgical procedures has grown on a worldwide scale, particularly for use in more complex operations. Such operations usually require meticulous handling of tissue, involve a narrow working space and limit the surgeon’s sense of orientation in the human body. Improvement in both tissue handling and working within a narrow working space might be achieved through the use of robotic assistance. Soft tissue navigation might improve orientation by visualizing important target and risk structures intraoperatively, thereby possibly improving patient outcome. Prerequisites for navigation are its integration into the surgical workflow and accurate localization of both the instruments and patient. Magnetic tracking allows for good integration but is susceptible to distortion through metal or electro-magnetic interference, which may be caused by the operation table or a robotic system. We have investigated whether magnetic tracking can be used in combination with the da Vinci^® (DV) telemanipulator in terms of stability and precision. We used a common magnetic tracking system (Aurora^®, NDI Inc.) with the DV in a typical operation setup. Magnetic field distortion was evaluated using a measuring facility, with the following reference system: without any metal (R), operation table alone (T), DV in standby (D) and DV in motion (Dm). The maximum error of the entire tracking volume for R, T, D and Dm was 9.9, 32.8, 37.9 and 37.2 mm, respectively. Limiting the tracking volume to 190 mm (from cranial to caudal) resulted in a maximum error of 4.0, 8.3, 8.5 and 8.9 mm, respectively. When used in the operation room, magnetic tracking shows high errors, mainly due to the operation table. The target area should be limited to increase accuracy, which is possible for most surgical applications. The use of the da Vinci^® telemanipulator only slightly aggravates the distortion and can thus be used in combination with magnetic tracking systems.

[Health status and causes of mortality in feral cats in a delimited area of the inner city of Berlin]

Results of the veterinary examination of feral cats living in a delimited area of Berlin city are presented. Between 1996 and 1999 thirty nine cats were investigated, among them eleven individuals twice. All animals were positive for one or several pathologies, but only seven cats were in bad condition. Most common were periodontal and gingival diseases, followed by conjunctivitis. Five cats were positive for FIV, seven for FeLV, one tomcat for both. Twenty six cats vanished during the study period of 42 months, only one third of cats survived and remained in the study area throughout. Four cats were given to pet lovers, nine cats disappeared without trace, seven animals died in traffic accidents and six cats died of illnesses. Cats less than three years of age vanished more often than expected from their representation in the population. Dirty or large feeding places for cats constitute a source of infections. Feeding sites should be accessible to only few individuals and left-overs that may attract stray cats, rats or birds should not remain at feeding places.

Differences between antigenic determinants of pig and cat zona pellucida proteins

Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.

Differences between antigenic determinants of pig and cat zona pellucida proteins

Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.